CN100481172C - Image display apparatus for writing display information with reduced electric consumption - Google Patents

Abstract

An image display apparatus for displaying gray-scale images by writing display information to an image display area of a panel. The display information includes values of a plurality of sub-fields that constitute one field. The image display apparatus converts an input image signal into a piece of display information so that a difference between sub-fields in correspondence with each other in adjacent high gray-scale levels becomes less. The image display apparatus displays a gray-scale image in accordance with the piece of display information.

Description

Has the image display unit that reduces electric consumption when being used for writing display information

The application is to be that August 23 calendar year 2001, application number are 01135742.8 and denomination of invention dividing an application for the application of the image display unit of electric consumption " have when being used for writing display information reduce " applying date.

Technical field

The present invention relates to a kind of display device, such as a kind of plasma display.Particularly the present invention relates to a kind of image display unit, can reduce power consumption when being used for writing display information.

Background technology

Typically, a kind of display device, such as a plasma display, be based in its display image that a kind of display mode of two values shows, display device comes the display gray scale image by a field in time domain being divided into a plurality of luminance weighted son fields of distributing thereon, and photoemissive ON/OFF of each son is controlled.For example, in order to show the image that has 256 gray levels, field is divided into 8 sons, and distribute 8 sons in chronological order luminance weightedly be " 1 ", " 2 ", " 4 ", " 8 ", " 16 ", " 32 ", " 64 " and " 128 ".Display device receives and to include corresponding to above-mentioned sub-field sequence, with a supplied with digital signal of (that is to say that lowest order is corresponding to minimum luminance weighted) of the reverse order of position order one group 8.

Figure 24 shown input gray grade that comprises received image signal and display gray scale and distribute to the son luminance weighted between relation.Figure 25 is a curve map based on data shown in Figure 24, shows the input gray grade of gray level ratio on transverse axis on the Z-axis.By providing voltage through address electrode to Cell display, the sub-field information that shows among the figure is written into Cell display as display message.

Address electrode has and is used for electric capacity that other electrode is driven.In addition, electric capacity also is positioned between the adjacent address electrode.When the voltage waveform of the voltage that is provided to address electrode alters a great deal, to consume a large amount of power for electric capacity being charged and discharging.In addition, consuming also increases with the increase that is presented at the pixel count on the display device in the amount of current on the address driver, perhaps increases with the increase that is used for the required driving voltage of addressing.

In order to solve top problem, Japanese Laid-Open Patent Application NO.10-187093 discloses the technical scheme that is equal to a kind of and shown in Figure 26.This technology is planned timing by the skew drive waveforms and is reduced current drain in address driver, expectation value according to the power quantity that in data driver, consumes, from the spatial frequency composition of input signal, remove high fdrequency component, perhaps according to the expectation value of power consumption, the low level of shows signal omitted show.

Japanese Laid-Open Patent Application NO.2000-66638 (P2000-66638A) discloses the technology of utilizing a kind of method to reduce the gray level of display image, wherein, forbid carrying less luminance weighted sub-field data and be written into or be changed according to the expectation value of in driver, losing quantity that from the data of the variation figure that shows, obtains.

Yet the timing method of conventional offset address drive waveforms has a shortcoming to be, needs to guarantee to be used for the time of offset address drive waveforms, and as a result of, needs to prolong the cycle of address drive waveforms.That is to say that it is proportional with the line number on display device being used for the address required time of driving on whole cycles of a field.Be used for required time that the address drives relative occupy very big ratio of field duration.As a result of, increase a little, then can be used for the photoemissive time can significantly reduce if be used for the required time that the address drives.This is very difficult for keeping brightness.

In addition, for other, the method that limits the quantity that shows position or display gray scale according to the expectation value of power consumption also has a shortcoming, the heat that budget accurately produces in driving arrangement, and this need add up to a large amount of image informations in time domain and spatial domain.This has just increased the scale of Circuits System, such as a memory devices.

Simultaneously, under the situation of routine techniques, the figure place that is used for display image only changes according to the expectation value of power consumption, depends on the image of demonstration in the above, and image degradation may appear in the minimizing of figure place and gray level.This method also has a problem to be, rely on image in the entire image the position and with the combination of another pattern, a definite pattern can be shown as a different pattern in entire image, perhaps should by the image that the time steadily moves may be interrupted move.These phenomenons make the beholder feel very unnatural.

Summary of the invention

Therefore, the purpose of this invention is to provide a kind of image display, when image display information was written into, its reality had reduced power consumption effectively.

Above-mentioned purpose is by realizing on the image display area display message being write a panel by an image display that is used for the display gray scale image, this display message comprises the value of a plurality of sons field that constitutes a field, this image display is characterised in that an input picture is converted to one section display message, so that the adjacent high grade grey level difference between consistent to each other a plurality of sons diminishes, and a gray level image is shown according to the section of display message.

Use above-mentioned structure, bring signal from input picture in the display message transfer, the high grade grey level with high brightness weighting can have a common son value.When this situation occurring, even the gray level in a definite scope of received image signal changes continually, the change frequency that is provided in the voltage waveform of address electrode also can reduce.This has just reduced the power consumption in address driver.Low luminance level in the received image signal can be reflected in the display message faithfully.Usually, by son field of opening smallest number and the low-light level part that the son field of smallest number is write the image of to regenerate in the panel.This makes a spot of power of drive dissipation.Therefore, even the low luminance level in the received image signal is reflected in the display message faithfully, the quantity of power that consumes in address driver can not alter a great deal.

On the contrary, usually, by opening and closing the regenerate hi-lite of an image of big quantum field.Therefore, for the amount that increases consumed power in the address driver, hi-lite has bigger possibility.As a result of, partly have more common writing information by allowing higher brightness, the effect that can expect to limit power consumption in the address driver can be better.

In above-mentioned structure, even have a common lower son value to such an extent as to input signal is converted high grade grey level, consequent difference is also less relatively.As a result of, if limit the quantity of gray level by this way, the beholder can not think image quality decrease.Therefore, image display can show from being low to moderate the image of high-grade brightness range, and can not make the beholder feel image quality decrease.

In the superincumbent image display, to such an extent as to can finish the increase of the conversion of received image signal along with a gray level in the received image signal, with the gray shade scale of a vicinity be the quantity increase of a common son value.

In the superincumbent image display, to such an extent as to can finish the increase of the conversion of received image signal along with a gray level in the received image signal, big step-length number increases, and wherein each step-length is an interval between the corresponding gray level in gray level in the received image signal and the display message.

In the superincumbent image display, the conversion that can finish received image signal is so that little luminance weighted the becoming that the place value of antithetical phrase field is distributed: " 0 " or " 1 ".

Structure above using, to such an extent as to received image signal is converted the increase along with a gray level in received image signal, having fixing little luminance weighted sub-number of fields increases.When a high-brghtness picture images was shown, this had limited the consumption of power in address driver.

As for a low-light level part of an image, because original minute differences is held between the gray level, the gray level of the minute differences of original image is reproduced.Usually, the low-light level of an image partly consumes a spot of electric current.Therefore, said structure provides a kind of high-quality image of the wide grey level range from the low-light level to the high brightness to show, reduces the power consumption in the address driver simultaneously.In addition, by constituting a kind of ON/OFF pattern of one group sub of a field, also can realize top purpose by an image display that is used for gray scale images each gray level by presentation video, this image display is characterised in that, a received image signal converted to one section display message so that along with the increase of a gray level in this received image signal, all be out or all be close and with an adjacent gray level be that the number of common continuous son increases.

Structure above using, for example, it can write fixing information so that all open or Close All has the son of the high brightness levels of low-light level weighting.When showing the high grade grey level part, or during the exhibit high brilliance part, this can be limited in the current consumption in the address driver.Also can change received image signal so that reduce sub-number of fields with such structure, in a definite scope of high grade grey level, a little number of fields of this between the adjacent gray levels is normally closed.This just can display image and do not reduce peak brightness, reduces the power consumption of address driver simultaneously on the whole.

By constituting a kind of ON/OFF pattern of one group sub of a field, also can realize top purpose by an image display that is used for gray scale images each gray level by presentation video, be characterised in that, (N-M) high bit of a N-position input digital image signal is first signal, the low M position of N-position input digital image signal is a secondary signal, wherein M and N are the integer of the 0 ≦ M ≦ N that satisfies condition, utilize secondary signal as an input with comprise that a plurality of delays carry out one and calculate and obtain a signal, the low M position of picked up signal all becomes " 0 " so that produce the 3rd signal, and obtains a signal on first signal and represent a display gray scale by the 3rd signal is added to.

By constituting a kind of ON/OFF pattern of one group sub of a field, also can realize top purpose by an image display that is used for gray scale images each gray level by presentation video, be characterised in that, (N-M) high bit of a N-position input digital image signal is a temporary transient display gray scale, wherein M and N are the integers of M ≦ N of satisfying condition, and carry out actual demonstration by a mistake of proofreading and correct between N-position input digital image signal and the temporary transient display gray scale, by a M-position line storage, utilize an error diffusion method to form an annulus.

In addition, a kind of image display of finishing top purpose comprises: according to a kind of ON/OFF pattern of the one group of son that constitutes a field, and the device that is used for the display gray scale image of each gray level by presentation video; And be used to make a N-position input digital image signal to carry out the error diffusion processing so that reduce quantity that shows the position and the device that shows resultant signal, wherein along with the increase of a gray level in the input digital image signal of N-position, the quantity of the demonstration position that is reduced increases by the unit of display pixel.

Structure above using can be calculated the quantity that effectively shows the position in each gray level of received image signal high speed response pixel, and different effective quantity of position that shows is assigned to a low-light level part and a hi-lite.As such result, hi-lite is shown the change that has limited the drive waveforms that is provided to address electrode simultaneously, and reduced power consumption in address driver, and, shown with original brightness for allowing address driver to consume the low-light level part of small amount of current.Should be noted that one group of son field of " than the low level " counterpart here, and less luminance weighted being assigned to than low level.

In addition, in the superincumbent structure, for hi-lite, even the quantity of significance bit is reduced, a mistake between the gray level of the gray level of received image signal and actual displayed also can be diffused into the periphery.This just can abundant really display gray scale.The difference of conventional error diffusion method is that effectively the quantity of demonstration position is fixed, image display of the present invention has increased from the demonstration mistake of the pixel accumulative total of neighboring pixel to a focusing, so that by coming video data from the determined figure place of the gray level of focused pixel, and meanwhile, according to the demonstration position of focused pixel, the new demonstration mistake that produces of pixel diffusion from the focused pixel to the periphery.This allows the quantity of effective bit width to change for each pixel, and in the scope of intensity level from low to high, realizes real fully display gray scale.

In the superincumbent image display, be added to by the signal that has an amplitude to and obtain display gray scale on the received image signal, this amplitude is corresponding to a gray level, can be clocklike cycle or irregular cycle.

In the superincumbent image display unit, the signal that is added with cycle of rule can be according to pixels, row or a signal being transformed of unit.

In the superincumbent image display, the signal that is added with non-regular periods can be according to pixels, row or a signal being transformed at random of unit

Structure above using, when showing an image, can limit the quantity of the gray level of actual use, can come display image by the quantity that is increased in visually mutually the same gray level, and utilize the error diffusion method, can prevent that the beholder from finding out a definite picture pattern simultaneously.

In the superincumbent image display, utilize the method for error diffusion or the method for dither, one shows the wrong periphery that can be diffused into a focused pixel.

Structure above using in order to improve picture quality, can enough a kind of known devices improve picture quality.

By in time domain, constituting a kind of ON/OFF pattern of one group sub of a field, also can realize top purpose by an image display that is used for gray scale images each gray level by presentation video, be characterised in that, in response to a received image signal, the zone that setting is made up of a plurality of neighbors, generate the section of a plurality of display message subsequently, they have the son that has model identical between the neighbor jointly, and according to a plurality of sections display gray scale images of display message.

Structure above using can determine that a such rule of gray level of scope generates display message according to be provided with one in received image signal, and when writing data, comes the limiting power consumption amount by allowing neighbor to have a common son value.Particularly importantly, for putting in order screen, be not to generate writing information, but foundation is provided with the rule of the gray level of a definite scope in received image signal according to a definite rule.So just can generate display message so that increase, limit the reduction of picture quality simultaneously because of reduced the effect that the Writing power that consumes brings in address driver.

In the superincumbent image display, can be used selectively corresponding to one section display message of the minimum change of an average gray level in the zone.

Structure above using, when writing data, processing obtains outside the effect of limiting power consumption amount by allowing neighbor to have a common son value, can prevent the mass change of an image being noted, since replaced write information, can be by the change of restriction average brightness value and the change of restriction brightness and tone.

In the superincumbent image display, a standard pixel can be set in this zone, and the gray level of getting rid of all pixels of this standard pixel in this zone at least is changed, to such an extent as to a plurality of display message sections have common son field, this a little field has identical pattern between neighbor.

Structure above using can be limited in the signal change between standard pixel and other pixel and can reduce the power that consumes, the original value of the pixel that maintains the standard simultaneously in address driver.This has prevented the marked change of image information and has limited decrease in image quality.

In the superincumbent image display, a standard pixel can be set in the zone, and when the difference between the gray level of standard pixel in gray level of a pixel in the zone and the zone is lower than a value, this value is determined according to a gray level of the standard pixel of representing in a received image signal, and the gray level of the gray level of pixel and standard pixel is adjusted to and is equal to each other in this time domain.

Structure above using, have with the pixel of the slightly different intensity level of the brightness of standard pixel by respectively with identical signal replacement, such as the signal of standard pixel.This replacement can not make spectators recognize image quality decrease.Because the signal of standard pixel and each signal of neighboring pixel mate fully, eliminated the variation between the signal of standard pixel and surrounding pixel.This has reduced the amount of writing power that consumes in address driver.

In the superincumbent image display, the son field that is included in jointly in a plurality of display message sections can be sub lower in all son fields.

Structure above using, neighbor have a common lower son value that has low-light level.When data were write, this had just limited the power that consumes in address driver, and had prevented the deterioration significantly of picture quality.

In the superincumbent image display, the zone can be made up of two adjacent lines.

Structure above using, the signal in the zone has a common value.Yet owing to demonstrate very strong each other correlativity in a pair of intrinsic row, this arrangement can not cause the deterioration significantly of image quality.Therefore, when data were write, this had limited the power that consumes in address driver.

In the superincumbent image display, the zone also or brokenly changes with the unit rule of pixel.

Structure above using, under the situation of the change of zone unit rule according to pixels (for example, a zone representing a tiling figure, figure such as a grid), can limit the frequency of signal change between the neighbor, simultaneously the gray level of each pixel of the mean flow rate of emphasis and whole graph area or tone rather than formation figure.When data were write, this had limited the power that consumes in address driver, has limited decrease in image quality simultaneously.Under the situation of the change of a zone non-rule of unit according to pixels, the details of for example representing a complicated image, such as " hair " or " texture ", and when high fdrequency component is removed from spatial frequency component, tend to make spectators to notice decrease in image quality, this structure can allow a plurality of son to have a common value, keeps the contrast between each pixel of original image simultaneously.When data were write, this had limited the power that consumes in address driver, and had prevented the deterioration significantly of picture quality.

By in time domain, constituting a kind of ON/OFF pattern of one group sub of a field, also can realize top purpose by an image display that is used for gray scale images each gray level by presentation video, be characterised in that, a zone of forming by a plurality of neighbors in response to a received image signal setting, signal level that subsequently should the zone is changed, and the luminance difference between the main gray level in the zone is changed and becomes to be not less than a determined value, and this determined value is to determine according to the luminance difference between the main gray level.

Structure above using can limit the signal change between pixel, and when data are write, has limited the power that consumes in address driver, has kept the contrast of image simultaneously.

In the superincumbent image display, the pattern (for example, chequer) of a rule of the unit formation according to pixels of the main gray level in the zone.

In the superincumbent image display, for every kind of demonstration look, the main gray level in the zone can be two-stage or gray level still less, and is every kind of pattern that shows a look rule of unit formation according to pixels.Especially, for example pattern can be a chequer or the pattern that tiling shows.

By in time domain, constituting a kind of ON/OFF pattern of one group sub of a field, also can realize top purpose by an image display that is used for gray scale images each gray level by presentation video, be characterised in that, a zone of forming by a plurality of neighbors in response to a received image signal setting, a standard pixel is arranged in this zone, change in the zone at least the gray level of all pixels of exclusion standard pixel subsequently so that the siding stopping number of fields, this sub-number of fields between the pixel of standard pixel and contiguous standard pixel is different, and be not less than a determined value so that the luminance difference between the main gray level in the zone changes over, this determined value is to determine according to the luminance difference between the main gray level.

Structure above using can limit the signal change between the pixel, and when data are write, has limited the power that consumes in address driver, has kept the contrast of image simultaneously.

Description of drawings

Below, in conjunction with the accompanying drawings, by exemplary description to a specific embodiment of the present invention, these and other purpose of the present invention, it is more apparent that advantage and characteristics will become.

In the accompanying drawings:

Fig. 1 is a block scheme, has shown that the present invention among the embodiment 1 uses the structure of a plasma display PD1 of a son display gray scale image;

Fig. 2 has shown the relation between input gray grade and the display gray scale;

Fig. 3 is the curve that Z-axis vs goes up input gray grade on display gray scale, the transverse axis;

Fig. 4 has shown the input gray grade of the embodiment of the invention 2 ionic medium display PD2 and the relation between the display gray scale;

Fig. 5 is a curve of going up input gray grade on display gray scale, the transverse axis based on the Z-axis vs of data shown in Fig. 4;

Fig. 6 has shown the input gray grade of the embodiment of the invention 3 ionic medium display PD2 and the relation between the display gray scale;

Fig. 7 is a curve of going up input gray grade on display gray scale, the transverse axis based on the Z-axis vs of data shown in Fig. 6;

Fig. 8 is a block scheme, has shown the structure of a plasma display PD4 in the embodiment of the invention 4;

Fig. 9 has shown by a true value that execution computing example in logical conversion unit is born results shown in Fig. 8;

Figure 10 is a block scheme, has shown that the present invention uses the structure of a plasma display PD5 among the embodiment 5 of son display gray scale image;

How Figure 11 display menu unit 34 carries out a selection;

Figure 12 is a form, and how display menu unit 34 carries out a selection;

Figure 13 is a block scheme, has shown that the present invention uses the structure of a plasma display PD6 among the embodiment 6 of son display gray scale image;

How Figure 14 display menu unit 41 carries out a selection;

Figure 15 is a form, and how display menu unit 41 carries out a selection;

Figure 16 is a block scheme, has shown that the present invention uses the structure of a plasma display PD7 among the embodiment 7 of son display gray scale image;

Figure 17 shows how level translation unit 48 is operated;

Figure 18 shows that level translation unit 48 is as the function of tabling look-up;

Figure 19 is the block scheme of a function, shows the structure that is used for determining table content shown in Figure 18;

Figure 20 shows the detail operations of level translation unit among the embodiment 7;

Figure 21 shows the detail operations of level translation unit among the embodiment 7;

Figure 22 shows the detail operations of level translation unit among the embodiment 7;

Figure 23 shows the detail operations of level translation unit among the embodiment 7;

Figure 24 is presented at the input gray grade of a conventional example ionic medium display PD2 and the relation between the display gray scale;

Figure 25 is a curve of going up input gray grade on display gray scale, the transverse axis based on the Z-axis vs of data shown in Figure 24; With

Figure 26 demonstration is used for being implemented in the conventional structure that address driver reduces the effect of power consumption.

Embodiment

Below in conjunction with embodiments of the present invention will be described by referring to the drawings.

Embodiment 1

Fig. 1 has shown the block scheme of a plasma display PD1 structure using a son display gray scale image.

As shown in Figure 1, plasma display PD1 comprises a received image signal converter unit 2, a sub-field information generation unit 3 and a plasma display panel apparatus 4.

Received image signal converter unit 2 comprises that a bit width is provided with unit 21 and one and door 22.

Sub-field information generation unit 3 becomes an image signal transformation that provides from received image signal converter unit 2 section of ON/OFF information (being sub-field information).Here, received image signal comprises that the pixel that is used for an image of handle formation is presented at the multiple gray level on the screen.Each ON/OFF message segment or sub-field information are represented one group of combination corresponding to the son field of one of gray level.Use each son field of a luminance weighted distribution in advance.Keep the light emission so that represent a corresponding gray level with one corresponding to this luminance weighted brightness by the summation of one group of son light quantity of launching.

The sub-field information that is generated by sub-field information generation unit 3 is written to a panel unit in the plasma display panel apparatus 4 through an address driver, and the light emission that is used for each pixel then is held.A Here it is so-called son time-division gradation display method.Plasma display PD1 utilizes the method display gray scale image.

Below together with the operation of the functional interpretation of each element being described in detail plasma display PD1.

In the present embodiment, represent each gray level by the sub-field information Duan Lai that forms by 6.Arrange six in order, from left to right, to lowest order, wherein maximum weighted is distributed to most significant digit and minimum weight is distributed to lowest order from most significant digit.Bit width is provided with unit 21 and is used for being included in the significance bit width of received image signal 1 each gray level with door 22 cooperative computation.For this purpose, bit width is provided with unit 21 a correction bit width for each gray level at first is set, and wherein in representing every group of position of a gray level, revises bit width and represents a series of position that is corrected in the present embodiment.It should be noted that here " significance bit width " expression is included in a series of position in the picture signal of reception, it can be used as display message.In addition, received image signal is to comprise the digital signal (for example 6) that many groups are determined figure place, and every group of representative constitutes the gray level of a pixel of a display image.

The basic skills of determining effective bit width is below described.For each low gray level, the bit width of (for example 6) is determined as the significance bit width on the whole scope of the position that receives.For other higher gray level, along with uprising of gray level, the significance bit width descends to the ratio of whole bit widths.In other words, along with the increase of gray level, the correction bit width that unit 21 settings are set by bit width is elongated.

Carry out a computing of determining with door 22 so that be fixed to " 0 " corresponding to what revise bit width than low level, this is to have a mind to arrange in the present embodiment.The darker part that lower gray level expressing display image is arranged here.As a result of, received image signal 1 median that is included in of the dark part of presentation image is used.The operation of each pixel is described below.

For example, suppose to receive a received image signal that has gray level " 50 ".Corresponding therewith, sub-field information generation unit 3 generates sub-field information " 110010 ", shows the ON/OFF combination of six son fields, wherein in this example of present embodiment, the opposite order of step-by-step preface is luminance weighted " 1 ", " 2 ", " 4 ", " 8 ", " 16 " and " 32 " are assigned on six.That is to say, as described earlier, arrange six positions in order, from left to right, from the most significant digit to the lowest order, wherein maximum weighted is assigned to most significant digit and minimum weight is assigned to lowest order.Here, suppose that bit width is provided with unit 21 and is arranged to lower 2 " 10 " revising bit widths, subsequently with door 22 outputs " 110000 " as display message, with higher 2 " 11 " as the significance bit width.As such result, two are fixed to " 0 " than low level.

With door 22 be that a logical operation is carried out in each position, and the result of output as determining the continuous signal (for example 6) that figure place is formed by one.All embodiment that this mode is applied to describe in the presents.It should be noted, have here a parts (not shown) be positioned in door 22 before, this component stores the relation between the ON/OFF combination of the picture signal that keeps by sub-field information generation unit 3 and son.These parts also are applied to embodiment 2-4.

Fig. 2 has shown the relation between the gray level that is included in the gray level in the received image signal and is used for display image.In other words, Fig. 2 has shown the relation between the input and output of received image signal converter unit 2 shown in Fig. 1.Fig. 3 is the curve that Z-axis vs goes up input gray grade on the display gray scale transverse axis.

For example, Fig. 2 represents that when one of input had picture signal of a gray level " 10 " (the sub-field information that is used for this input value is " 001010 "), output gray level also was " 10 " (the sub-field information that is used for this output valve is " 001010 ").In other words, because input gray grade " 10 " has a low-light level, bit width is provided with unit 21 and just is arranged to like this revising bit width, promptly allows and the picture signal identical sub-field information value of door 22 outputs with input.In other words, whole bit widths of reception are determined as the significance bit width.

On the other hand, when one of input had picture signal of a gray level " 50 " (the sub-field information that is used for this input value is " 110010 "), output gray level was " 48 " (the sub-field information that is used for this output valve is " 110000 ").In other words, because input gray grade " 50 " has a high brightness, bit width is provided with unit 21 and just is arranged to like this revising bit width, promptly allows to export the sub-field information value that is fixed to " 0 " than low level with door 22, has lacked significance bit " 1 " than received image signal.

Be appreciated that top example based on Fig. 2 and 3, bit width is provided with unit 21 and according to the mode at the dark part of image the correction bit width is set, and the bit width of received image signal 1 is used as the significance bit width; And utilize the handle of having a mind to be fixed to " 0 " than low level, along with the reduction of gray level, it is elongated to revise bit width.Use so a kind of operation, produce big " step-length " (step-length of making a leapleap forward shown in Fig. 3, Y1 represents by arrow) along with the reduction of input gray grade, form step-length by the interval between the input and output gray level.This can be by confirming with reference to figure 2.In a box that has dotted line to center on,, have little luminance weighted son field and be fixed to " 0 " in that output is found in the sub-field information corresponding to higher gray level.

As mentioned above, sub-field information generation unit 3 is transformed into the output signal from received image signal converter unit 2 the sub-field information of an expression ON/OFF pattern.This child field display message is with after address driver is sent to plasma display panel.

As mentioned above, along with uprising of gray level, the ratio that the significance bit width accounts for whole bit widths reduces.Use this arrangement, the drive waveforms that goes up address electrode at a succession of adjacent input pixel value (gray level) can not change at least.As such result, one whole on drive waveforms change very for a short time, this has just reduced the power consumption of address driver.

Should be noted that reduction, produce big demonstration " step-length " along with gray level, or a kind of discontinuous gray level.Yet, for saying on the whole, show that step-length is to relative ratios's step-down of display gray scale.In addition, can use a gray scale method of adjustment simultaneously, such as the error diffusion method.As a result of, can provide a kind of high quality graphic to show.

It should be noted, although the gray scale of input and output picture signal is by being formed to the value of " 63 " from " 0 " in the present embodiment, and luminance weighted value is " 1 ", " 2 ", " 4 ", " 8 ", " 16 ", " 32 ", but the present invention can use any other proper range value to realize.

Embodiment 2

To describe a kind of plasma display PD2 of second embodiment of the invention, emphasis is described the difference with embodiment 1.

Fig. 4 shown under the situation of plasma display PD2, is included in the gray level in the received image signal and is used for relation between the gray level of display image.In other words, Fig. 4 has shown the relation between the input and output of the received image signal converter unit 2 shown in Fig. 1.Fig. 5 has shown that Z-axis vs goes up display gray scale. input gray grade curve on the transverse axis.

In this embodiment, along with the reduction of gray level, wittingly be fixed to " 1 " than low level.

For example, when one of input had picture signal of a gray level " 10 " (the sub-field information that is used for this input value is " 001010 "), output gray level also was " 10 " (the sub-field information that is used for this output valve is " 001010 ").In other words, because input gray grade " 10 " has a low-light level, bit width is provided with unit 21 and just is arranged to like this revising bit width, promptly allows and the picture signal identical sub-field information value of door 22 outputs with input.In other words, whole bit widths of reception are determined as the significance bit width.

On the other hand, when one of input had picture signal of a gray level " 50 " (the sub-field information that is used for this input value is " 110010 "), output gray level was " 55 " (the sub-field information that is used for this output valve is " 110111 ").In other words, because input gray grade " 50 " has a high brightness, bit width is provided with unit 21 and just is arranged to like this revising bit width, promptly allows to be fixed to than low level with door 22 outputs the sub-field information value of " 1 ".

In the superincumbent situation, for example, bit width is provided with unit 21 and 3 " 101 " is set as revising bit width.Receive correction bit width " 101 " subsequently with door 22, utilize these actuating logic computings, and output " 110111 " expression gray levels " 55 " are as display message.Like this, as a result of, be fixed to " 1 " than low level.

As mentioned above, in response to the input gray grade that has high brightness, the variation between the adjacent display brightness level (output gray level) is small, and lower son field is fixed.Use such arrangement, the drive waveforms that goes up address electrode at a succession of adjacent input pixel value (gray level) can not change.This has just reduced the power consumption of address driver.

Compare with embodiment 1, maximum display gray scale wherein is lower than maximum input display gray scale, and this arrangement in the present embodiment has effectively kept peak brightness.

Embodiment 3

To describe a kind of plasma display PD3 of third embodiment of the invention, emphasis is described the difference with embodiment 1 and 2.

Fig. 6 shown under the situation of plasma display PD3, is included in the gray level in the received image signal and is used for relation between the gray level of display image.In other words, Fig. 6 has shown the relation between the input and output of the received image signal converter unit 2 shown in Fig. 1.Fig. 7 has shown that Z-axis vs goes up display gray scale. input gray grade curve on the transverse axis.

In this embodiment, along with the reduction of gray level, wittingly be fixed to " 0 " than low level.But near one group of input gray grade of maximum gray scale, when they are to export this input gray grade during as display gray scale.

For example, when one of input had picture signal of a gray level " 10 " (the sub-field information that is used for this input value is " 001010 "), output gray level also was " 10 " (the sub-field information that is used for this output valve is " 001010 ").On the other hand, when one of input had picture signal of a gray level " 50 " (the sub-field information that is used for this input value is " 110010 "), output gray level was " 48 " (the sub-field information that is used for this output valve is " 110000 ").In addition, when one of input had picture signal of a gray level " 60 " (the sub-field information that is used for this input value is " 111100 "), output gray level also was " 60 " (the sub-field information that is used for this output valve is " 111100 ").In other words, owing to the close maximum gray scale of input gray grade " 60 ", bit width is provided with unit 21 and just is arranged to like this revising bit width, i.e. the identical sub-field information value of those values of received image signal is exported and be used for to permission and door 22.

Use such arrangement, in response to the centre and the high input gray grade that has middle and high brightness, the variation between the adjacent display brightness level (output gray level) is very little, and lower son field is fixed.This can make the drive waveforms of the address electrode on a succession of adjacent input pixel value (gray level) not change.This has just reduced the power consumption of address driver.

In addition, for one group of close maximum gray scale (in the box that centers on by dotted line among Fig. 6) input gray grade, have little luminance weighted son field and be set to " opening ".This arrangement has effectively kept peak brightness.

Embodiment 4

Fig. 8 has shown the structure of a plasma display PD4 in the embodiment of the invention 4.Fig. 9 has shown by a true value that execution computing example in logical conversion unit is born results shown in Fig. 8.In conjunction with describing the present invention with reference to figure 8 and 9.

As shown in Figure 8, plasma display PD4 comprises a random pattern generation unit 5, an adder unit 6, be used for carrying out addition to received image signal 1 with from an output of random pattern generation unit 5, a bit width is provided with unit 7, be used for being provided with a bit width corresponding to being included in 1 one gray levels of received image signal, with door 8 and 9, be used to be used to carry out a kind of logical operation from the output that adder unit 6 and bit width are provided with unit 7, a logical conversion unit 10, be used for a logical conversion is carried out in the output that unit 7 is set from bit width, one and door 11, be used for the logical and between completion logic converter unit 10 and the adder unit 134, by coefficient and delay (coefficient elements 133 of forming an error diffusion ring, a line storage 132, a delay/coefficient elements 133, adder unit 134 and similar unit) an error diffusion processing unit 13 being formed, an adder unit 14, be used for carrying out addition with the output of door 8 and 11, a sub-field information generation unit 3, be used for an image signal transformation that comprises a gray level is become the ON/OFF pattern of a seed field, with a plasma display panel apparatus 4, be used for a gray level image being shown according to sub-field mode.

Now, together with the explanation of each component function, will the operation of the plasma display PD4 of present embodiment be described.According to the gray level of received image signal 1, random pattern generation unit 5 generates a random pattern RPa.For example, random pattern RPa is following.When the gray level of received image signal 1 during less than " 16 ", a place value " 0 " is added to the lowest order of gray level; And when the gray level of received image signal 1 was not less than " 16 ", a place value " 1 " was added to the lowest order of gray level.Adder unit 6 is added to a place value according to random pattern RPa the lowest order of gray level.This arrangement has prevented a definite display pattern, can be after this operation, becoming attractive one fixedly after the figure, in the error diffusion of carrying out, generate display pattern that this is determined.

Bit width is provided with unit 7 and generates a control signal figure morpheme BCP for each pixel from received image signal 1, and this BCP is corresponding to a bit width M who is used for actual displayed.For example, following prerequisite sets in advance.(A) when the gray level of received image signal 1 less than N1, during M=0.(B) be not less than N1 and less than N2, during M=1 when the gray level of received image signal 1.(C) be not less than N2 and less than N3, during M=2 when the gray level of received image signal 1.(D) gray level when received image signal 1 is not less than N3, during M=3.In above-mentioned prerequisite, N1, N2 and N3 are the integers of N1＜N2＜N3＜N of satisfying condition.Then, bit width is provided with unit 7 and generates control signal figure morpheme " 000 ", and " 001 ", " 011 " and " 111 " corresponds respectively to M=1, M=2, M=3, and M=4.

Finish a logical operation between adder unit 6 and the control signal then, this logical operation is the oppositely output that bit width is provided with unit 7.As such result, when the output of adder unit 6 is that " 00110010 " is when representing gray level " 50 ", a value in four values (" 00110000 "-" 00110010 "), a result of one of lower 0-3 position that as many as intercepting is exported from adder unit 6.In addition, finish adder unit 6 and bit width a logical operation between the unit 7 is set.As a result, be provided to being actually of adder unit 134 and equal the lower 3 of adder unit 6 output.

The signal that is provided to adder unit 134 is equivalent to poor between display gray scale and the input gray grade.The output of adder unit 134 is sent to so-called error diffusion ring, the error diffusion ring be by with door 9, coefficient elements 131, line storage 132, and a system forming of delay/coefficient elements 133.Thereby, by " carry " signal from error diffusion ring output result being added in the output with door 8, the value than low level that this output equals to have been intercepted has been intercepted than low level and real, and an image that has recovered original gray level as much as possible is revealed.

Though, in the present embodiment, determine to show the quantity of significance bit with the unit of pixel according to each pixel value in the received image signal.But as a result of, the method for a kind of typical conventional error diffusion own can not be applied to present embodiment.In the present embodiment, determining effectively to show in the process of position, not to come the diffusion of execution error correctly by increasing a 1-position carry signal, but by one is added on the signal from the value that the result of a logical operation of each pixel obtains according to the quantity of intercepting position, this signal is calculated by error diffusion that a plurality of positions of output are formed.

Fig. 9 has shown by true value that example bore results of logical conversion unit 10 computings.As shown in Figure 9, in response to bit width the input of the control signal pattern position BCP of 7 one outputs in unit is set, a control signal that is output is sent to and door 11.For example, in response to an input " 000 ", repeatedly carry out add " 1 " up to this value by 7 of carries to the.At this moment, lower 6 is " 000000 ".Use the output signal that this principle produces other.

Here it should be noted that above-mentioned error diffusion ring can be realized by a kind of simple logical operation circuit or adding circuit.Can make the high-speed computation of error diffusion ring, preferably the error diffusion ring be made a kind of circuit, this circuit can easily be finished with a LSI.

Now, description error diffusion when effective bit width changes for each pixel is handled and how to be finished.

As discussed previously, with the output of door 8 " temporary transient video datas ", it intercepted than low level.When signals handling ring 13 outputs from error diffusion are " 0 ", be used to show with the output of door 8.Yet normal, " showing wrong " from peripheral pixel diffusion this moment has been accumulated at the error diffusion ring.Therefore before showing, need to proofread and correct " temporary transient video data ", this based on the result of the summation of the demonstration mistake of accumulative total and with the output of door 9, this output is to show the intercepting mistake this moment one of a focused pixel.Here, suppose that a large amount of mistakes and the focused pixel of having accumulated peripheral pixel have an intermediate grey scales, the value that peripheral pixel has can be than wrong high " 1 " of focused pixel intercepting or more.Under the circumstances, the correction of " temporary transient video data " is not gone up and is finished by " intercepting mistake+1 " is added to " video data temporarily " simply, but by using a value of a result of calculation, what wherein add up mistake is changed to " 0 " than low level, true value as shown in Figure 9.Use this arrangement, the quantity of the position of can remaining valid and allow adder unit 14 that the mistakes from peripheral pixel diffusion are added to by effectively for the gray level of representative and produce video data.Therefore, can effectively the demonstration position relevant with the gray level of received image signal 1 be provided with simultaneously with the suitable control display gray scale of the unit of pixel by the error diffusion method.

More particularly, in the above example, with the output of door 8 be that " 00110000 " and significance bit quantity are 6, and the output of logical conversion unit 10 also is 6.Here, for example hypothesis is " 00110100 " with the output of door 11, and then the output with door 14 is " 01000100 ".This expresses and is fixed to the effect of " 0 " than low level described in the above embodiments 1, and error diffusion is handled and is performed simultaneously.

As mentioned above, one of feature of present embodiment is to be used for be fixed to " 0 " and calculating door 11 (because the output signal of logical conversion unit 10 is " 0 " than low level) than low level.In addition, another feature of present embodiment is in the centre that is limited in showing than signal change frequent on the low level and the higher gray level, although because adder unit 14 output display gray scale, and that adjacent centre wherein or higher gray level have is common than low level.This has just reduced the consumption of electric current in the address driver of plasma display panel device.In addition, even the bit width of intercepting changes for each pixel, in response to the pixel around wrong can correctly being diffused into of variation demonstration of bit width.This just can provide a kind of high-quality image to show the gray level of a wide region from low-light level to high brightness, reduces the power consumption in the address driver simultaneously.

The output that should note adder unit 14 can comprise a kind of overflowing, and this can be handled by limiter 15.

As mentioned above, present embodiment provides a kind of high-quality image to show the gray level of a wide region from low-light level to high brightness, reduce the power consumption in the address driver simultaneously, and by error diffusion method correction gamma characteristic, these can be by being provided with effective demonstration position and a processing of carrying out in response to the demonstration mistake of calculating with the gray level of pixel unit input being realized.

Although the quantity of significance bit is to change dynamically with pixel unit, the parts that present embodiment constitutes the error diffusion ring can be logical operation circuit system or the adding circuit systems with simple structure.This makes present embodiment be easy to realize in a LSI and can high-speed computation.

Embodiment 5

Figure 10 is a block scheme, has shown that the present invention uses the structure of the signal processing of a plasma display PD5 among the embodiment 5 of son display gray scale image.

As shown in figure 10, plasma display PD5 comprises a line storage 30, absolute difference computing unit 31, an absolute value that is used to calculate a difference between two input values and calculates this difference, comparing unit 32, arithmetic logic unit 33, selected cell 34, sub-field information generation unit 3, be used to generate sub-field information and be a plasma display panel apparatus 4 of a panel, on panel, connected various driving circuits with circuit.

In Figure 10, input digital image signal of element number 1 expression, the information of element number 35 expression even/odds shows that line number is an even number or an odd number, element number 36 an expressions even/odd information shows that number of fields is an even number or an odd number.

The operation of the image display with top structure is described below.Also each functions of components will be described.

At first, for every pair of neighbor, a difference between the gray level of pixel on the vertical adjacent lines of received image signal 1 in the absolute difference computing unit 21 calculating line storages 30, and the absolute value that calculates this difference.Comparing unit 32 is compared the predetermined threshold value (TH) of absolute value and each pixel.Determine predetermined threshold value (TH) based on the experience relevant with the effect that reduces write current, this will be described later.Use other the threshold value that may occur arbitrarily from now on.

Comparative result (signal 37) is imported into arithmetic logic unit 33.In addition, arithmetic logic unit 33 receives a row even/odd information and an even/odd information at comparative result.Selected cell 34 is current row selection signal " a " or is previous row selection signal " b ".Selection mode depends on the relation shown in Figure 11 and 12.

In order more specifically to make an explanation, the example of an even field situation will be described in conjunction with reference Figure 11 and 12.When be expert at 0 and row 1 on difference between the gray level of pixel when very big, when they are used to row 0 and row 1 respectively, be expert at 0 and row 1 on signal be output; And when difference hour, the signal on the output row 0 is used for row 0 and row 1.This rule also is applicable to the situation of an odd field.From the selection signal of selected cell 34 output as a display gray scale (signal 38).

Desirable is that between even number and odd field, the combination of every pair of row that input value is compared is different, as shown in figure 11.That is to say, under the situation of an even field, relatively be to be expert at 0 and 1,2 and 3,4 and 5 ... between carry out; Under the situation of an odd field, relatively be expert at 1 and 2,3 and 4,5 and 6 ... between carry out, the gray level that this arrangement has been eliminated fully by pixel on every row changes the visual effect that is produced.

As mentioned above, between the difference between two signals is lower than as a pair of adjacent lines during the threshold T H of comparative result, every pair of oval represented by among Figure 11, then two signal values are adjusted to and are equal to each other.This just makes two groups of son fields on two row have identical value.Therefore, limit the variation in the drive waveforms of address electrode, and reduced the current drain in address driver.Here it should be noted that the above-mentioned arrangement that allows two signals on the adjacent lines have identical value can not bring obvious variation in display image for naked eyes, thereby can not cause image quality decrease.In addition, two signals on the adjacent lines can not change in the edge of image part.This means decrease in image quality, unclear or can't see the variation of marginal position such as edge fog.

In the present embodiment, even number or odd number provisional capital have complete original signal.As a result of, even threshold T H is arranged to a high value so that increase the effect that reduces current drain, original image information also always is held by even number or odd-numbered line.This has just stoped the deterioration significantly of picture quality.

Embodiment 6

Figure 13 is a block scheme, has shown that the present invention uses the structure of the signal processing of a plasma display PD6 among the embodiment 6 of son display gray scale image.

The difference of structure shown in Figure 13 and structure shown in Figure 10 is to have an average detection unit 39 and a line storage 40, and replaces selected cell 34 with selected cell 41.

Now, will the difference of embodiment 6 with embodiment 5 be described emphatically.

Directly received image signal 1 is input to average detection unit 39 by two-way through line storage 30.The output of average detection unit 39 is imported into selected cell 41 through line storage 40.Selected cell 41 receives the output of three unit: line storage 30, and average detection unit 39 and line storage 40, and according to the execution of the relation shown in Figure 14 and 15 selection, and export selected results.

In order more specifically to make an explanation, will be in conjunction with example refer to figs. 14 and 15 an even field situation of description.When be expert at 0 and row 1 on difference between the gray level of pixel when very big, when they are used to row 0 and row 1 respectively, be expert at 0 and row 1 on signal be output; And, has the signal (" c " in " input of selection " row) of two signal value mean values for row 0 and row 1 one of output when difference hour.This rule also is applicable to the situation of an odd field.

As mentioned above, when the difference between two signals on the adjacent lines is very little, replace each value of two signals with their mean value; And when difference was very big, signal was output.This can be restricted to the variation in the drive waveforms of address electrode and reduce power consumption in the address driver, has limited decrease in image quality simultaneously.

Here the arrangement that should be noted that the mean value replacement signal value of two signals of top usefulness can not bring tangible image quality decrease, even threshold T H1 is arranged to a high value.This is because the calculating of mean value always keeps half of the former information that begins.

It should be noted at this, in embodiment 5 and 6, can between every group of three or more neighbor, carry out for the comparison between the gray level of every pair of neighbor execution on the vertical adjacent lines.In the case, a standard pixel is set in comprising each zone of a definite sets of adjacent pixels, to such an extent as to and the gray level that comprises all pixels of this standard pixel in the change zone at least increases the quantity of the display message section with common son, this a little field has identical pattern between neighbor.(a) represent a difference between two signal values of gray level of two pixels and a threshold value of (b) under the situation of two values comparisons, carrying out, at (a) and the comparison (b) with identical a situation that is chosen to standard pixel in two pixels.

In another kind of variation pattern, a standard pixel is set in comprising each zone of a definite sets of adjacent pixels, and when gray level of a pixel in the zone and the difference between the standard pixel during less than a determined value, the gray level of the gray level of pixel and standard pixel is adjusted to mutually the same in the zone.

Embodiment 7

Usually, in showing a kind of pattern of checkering, the brightness of pixel vertical and flatly change.The display message that alters a great deal is written in the address electrode.That is to say that the drive waveforms of address electrode alters a great deal, and when the driver write data of address, increased power consumption.The image display of present embodiment is based on the original gray level of wanting in the controlling party grid pattern zone, so that reduce the change of the drive waveforms of address electrode, and limits current drain when the driver write data of address.Next describe the structure and the operation of image display in detail.

Figure 16 is a block scheme, has shown that the present invention uses the structure of the signal processing of a plasma display PD7 among the embodiment 7 of son display gray scale image.

As shown in figure 16, plasma display PD7 comprises a signal processing unit, is used to generate the display message that offers plasma display panel apparatus, chequer detecting unit 41, level H detecting unit 42, level L detecting unit 43, difference detecting unit 44, comparing unit 45, average detection unit 46, level H/L judging unit 47, level translation unit 48, an arithmetic logic unit 49 and a selected cell 50.

For example, the chequer that chequer detecting unit 41 detects as the part of received image signal 1, wherein its value variation of unit rule according to pixels.Level H detecting unit 42 detects a signal with high brightness " level H " in the signal that constitutes chequer.Level L detecting unit 43 detects a signal with low-light level " level L " in the signal that constitutes chequer.The difference that difference detecting unit 44 detects between level H and the level L.Threshold T H2 of comparing unit 45 usefulness compares higher so that whom judges with this difference.It should be noted that based on the pixel value that constitutes chequer, each among level H and the level L can be a plurality of different values.But in the present embodiment, for simplicity, suppose that among level H and the level L each is a single value.This can not change the operation or the effect of present embodiment.

A mean value between average detection unit 46 compute level H and the level L.Level translation unit 48 produces a pair of in addition " level H " and " level L " according to this to level H and level L.

Arithmetic logic unit 49 determines to select chequer detecting unit 41, an output of comparing unit 45 and 47 outputs of level H/L judging unit, and selected cell 50 is delivered in an output of selecting.

Figure 17 shows the operation of level translation unit 48.As shown in figure 17, based on the difference between the intensity level that constitutes chequer, a value of selected cell 50 is determined to be imported in level translation unit 48, and whether it is a chequer, and the gray level of pixel is high or low.

Here, the operation of level translation unit 48 will be described in detail.As shown in figure 18, level translation unit 48 plays the effect of table look-up (LUT1 and LUT2), and this table is used to calculate respectively according to level H and level L " the level H ' " and " level L ' " of new signal.The output of this table " level H ' " and " level L ' " are determined so that " the level H " and " level L " of they and input signal has how public place value, make mean value between " level H " and " level L " near the mean value between " level H ' " and " level L ' " as much as possible, and make difference between " level H " and " level L " as much as possible near the difference between " level H ' " and " level L ' ".

Figure 19 shows the example of the structure of determining table content.To operation that use structure shown in Figure 19 be described.When two intensity levels of input when " level H " and " level L " (in this embodiment, represent level by sub-field information), the position replaces unit 481 and public affairs of 482 usefulness are worth the low level that " Pi " replaces " level H " and " level L " respectively, and output " LHi " and " LLi ".The mean value that average detection unit 483 calculates between " level H " and " level L ".The mean value that average detection unit 484 calculates between " LHi " and " LLi ".Difference " Ei " between difference detecting unit 485 calculating mean value detecting unit 483 and 484 the output.The value " Pi " that is used to replace the input signal low level is divided into 8 kinds: " 000 ", and " 100 " ..., " 111 ".A combined value of " LHi " and " LLi " is determined to be the output of tabling look-up shown in Figure 180 when minimum when an analog value " Ei " becomes.According to lower three, use the above-mentioned value " level H ' " that produces from " level H " and " level L " of tabling look-up to have identical pattern with " level L ' ".Therefore, a chequer of forming by " level H ' " and " level L ' ", compare with a pattern of forming by " level H " and " level L ", when the driver write data of address, limited the variation in the drive waveforms of address electrode and reduced current drain.In addition, because the mean value between " level H " and " level L " approaches the mean value between " level H ' " and " level L ' ", fully kept the mean flow rate and the tone of chequer.

Now, in conjunction with the operation that will describe present embodiment with reference to Figure 17.As a result of the content of reference Figure 17, when judging that a received image signal is not a chequer, received image signal is output the (" d ") in " input of selection " row.This is that the consumed current amount is little when the driver write data of address because in this case.When an input picture be the height of a chequer and chequer and the difference between the low luminance level hour, the height of chequer and low luminance level are all by mean value (" a " in " input of the selection " row) replacement with them.When input picture is a difference between a chequer and height and low luminance level when big, the height of chequer and low luminance level are all by with the signal with identical low level (" b " and " c " in " input of selection " row respectively) replacement.In fact, finish b by level H/L judging unit 47 " and " c " between selection.For example, compare by mean value and each pixel value to chequer, level H/L judging unit 47 is easy to carry out such operation.

Figure 20 has shown the relation between sub control model and the input gray grade, and this moment, gray-scale displayed level image had 12 son fields, luminance weighted " 1 ", " 2 ", " 4 ", " 8 ", " 16 ", " 24 ", " 32 ", " 32 ", " 32 ", " 32 ", " 32 " and " 32 " distribute to them.

Figure 21-23 has shown the operation example corresponding to Figure 17.Each figure of Figure 21-23 has shown a processing procedure that " the level H " and " level L " that constitute an input chequer is transformed into " the level H ' " and " level L ' " that be output.

Now, will provide an operation example with reference to Figure 20 and 21.

As shown in figure 20, " when forming with a son value of " 0 ", level translation unit 48 should value as down conversion by gray level " 63 " when an input chequer.The sub-field information that is used for gray level " 63 " is expressed as " 1110011 " (by the order from lowest order), corresponding to brightness value " 1+2+4+0+0+24+32=63 ".In other words, it comprises with gray level " 0 " and is expressed as different 5 of the corresponding positions of " 0000000 ".When if these signals are output, address driver will consume a large amount of power so that write data.For avoiding this situation, to be used respectively for two signals be that a public value substitutes to lower three of these signals.Especially, for lower three can choose wantonly in " 000 "-" 111 " of 8 values, and are the most selected near " 001 " of mean value " 31.5 " between gray level " 63 " and " 0 ".Gray level " 63 " and " 0 " are used gray level " 63 " and " 4 " corresponding to the pattern of selecting " 001 " to replace subsequently.As shown in figure 20, gray level " 60 " is expressed as " 0010011 " (by from order of lowest order) and gray level " 4 " is expressed as " 0010000 ".These bit patterns only have two different positions (son field) on corresponding bit position.Use this arrangement, for writing data, address driver consumes a spot of power.

Hope obtains to reduce the same effect of current drain than low level by simple intercepting.Bright the gray level that constitutes chequer will be " 60 " and " 0 ", and the mean value between them will be " 30 " but in the case.With respect to the mean value in the example above the present embodiment " 32 ", this mean value and original mean value " 31.5 " have very big difference.

In conjunction with reference to Figure 20 and 22, will provide another operation example.

As shown in figure 20, " when forming with a son value of " 15 ", level translation unit 48 should value as down conversion by gray level " 48 " when an input chequer.The sub-field information that is used for gray level " 48 " is expressed as " 000111 " (by the order from lowest order), corresponding to brightness value " 0+0+0+8+16+24=48 ".In other words, it comprises with gray level " 15 " and is expressed as different 5 of the corresponding positions of " 111100 ".Corresponding to 8 couple of one of gray level " 48 "-" 55 " and any of gray level " 8 "-" 15 ", optional " 000 "-" 111 " in 8 lower-3-place values, as shown in figure 22, the most selected near " 001 " that has mean value " 32 " of mean value " 31.5 " between gray level " 48 " and " 15 ".Gray level " 48 " and " 15 " are used gray level " 52 " and " 12 " corresponding to the pattern of selecting " 001 " to replace subsequently.As shown in figure 20, gray level " 52 " is expressed as " 001111 " (by from order of lowest order) and gray level " 12 " is expressed as " 001100 ".These bit patterns only have two different positions (son field) on corresponding bit position.Use this arrangement, for writing data, address driver consumes a spot of power.

In conjunction with reference to Figure 22 and 23, will provide an operation example again.

As shown in figure 20, " when forming with a son value of " 2 ", level translation unit 48 should value as down conversion by gray level " 32 " when an input chequer.The sub-field information that is used for gray level " 32 " is expressed as " 000101 " (by the order from lowest order), corresponding to brightness value " 0+0+0+8+0+24=32 ".In other words, it comprises with gray level " 2 " and is expressed as different 3 of the corresponding positions of " 010000 ".Corresponding to 8 couple of one of gray level " 32 "-" 39 " and any of gray level " 0 "-" 7 ", optional " 000 "-" 111 " in 8 lower-3-place values, as shown in figure 23, with gray level " 33 " and " 1 " between identical " 001 " that has mean value " 17 " of mean value selected.Gray level " 32 " and " 2 " are used gray level " 33 " and " 1 " corresponding to the pattern of selecting " 001 " to replace subsequently.As shown in figure 20, gray level " 33 " is expressed as " 100101 " (by from order of lowest order) and gray level " 1 " is expressed as " 100000 ".These bit patterns only have two different positions (son field) on corresponding bit position.Use this arrangement, for writing data, address driver consumes a spot of power.

As mentioned above, in the present embodiment, from input picture, detect a chequer, and in order to the public bit pattern that pixel unit constitutes this chequer replace quantification at least than low level.When the driver write data of address, this arrangement has limited the variation in the drive waveforms of address electrode and has reduced power consumption.Replace the gray level of input so that the mean value between height and the low luminance level can not alter a great deal with the gray level that is determined.This arrangement has limited the variation in display brightness and tone.When a chequer that has little difference was detected, this difference was the difference that constitutes between the gray level of chequer, replaces each gray level with the mean value of gray level.This will further improve the effect that reduces power consumption.When a chequer that has big difference was detected, this difference was the difference that constitutes between the gray level of chequer, and the high bit of gray level is retained.Use this arrangement, can keep a definite level difference between the gray level that constitutes chequer, and keep the fundamental characteristics of chequer, promptly chequer is made up of two main gray levels: one has high brightness, and another has low-light level.Thereby use this arrangement, when the driver write data of address, limited the variation in the drive waveforms of address electrode and reduced power consumption, and picture quality does not have too big variation.

Present embodiment the situation of a graticule as an example.Yet the present invention goes for any " complex image pattern district ", such as a kind of tiling display mode, and a large amount of consumed powers of address driver when carrying out write data.In the case, as present embodiment, can obtain identical effect.

Although in conjunction with the accompanying drawings with the mode of example to the comprehensive description that the present invention carries out, should be understood that for ability and those of ordinary skill, can carry out various changes and modification.Therefore, under the situation that does not break away from category of the present invention, think that these changes and modification are included among the present invention.

Claims (8)

1. image display, a kind of ON/OFF pattern of one group of son by constituting a field, each gray level of presentation video is come gray scale images, and this image display comprises:

An input picture converting unit is used for received image signal is converted to image information;

A sub-field information generation unit is used for producing display message according to the image information from the output of input picture converting unit for each son field; And

An address driver is used for sub-field information generation unit is write image display area for each son display message that produces, wherein,

When the difference of the gray level of pixel on the vertical adjacent lines of received image signal during less than the predetermined threshold in the zone of forming by a plurality of adjacent image points, described input picture converting unit is changed described received image signal, thereby makes that to be used for the display message formed corresponding to the value by a plurality of sons of the son of a plurality of adjacent image points mutually the same.

2. image display as claimed in claim 1, wherein

Use one section display message selectively corresponding to the minimum change of an average gray level in the zone, when the difference of the gray level of pixel on the vertical adjacent lines of received image signal during less than the predetermined threshold in the zone of forming by a plurality of adjacent image points, described input picture converting unit is changed described received image signal, thereby makes that to be used for the display message formed corresponding to the value by a plurality of sons of the son of a plurality of adjacent image points mutually the same.

3. image display as claimed in claim 1, wherein,

A standard pixel is set in this zone, to such an extent as to and comprise at least in the change zone that all pixel gray levels of this standard pixel increase the quantity of the display message section with common son field.

4. image display as claimed in claim 1, wherein,

A standard pixel is set in the zone, and when the difference between the gray level of standard pixel in gray level of a pixel in the zone and the zone is lower than gray level of standard pixel that a foundation represents and during definite value, the gray level of the gray level of pixel and standard pixel is adjusted to and is equal to each other in the zone in a received image signal.

5. image display as claimed in claim 2, wherein,

Sub that is included in jointly in a plurality of display message sections is the lower son field of weight in all son fields.

6. as the image display of one of claim 1-5, wherein,

Described zone is made up of two adjacent lines.

7. as the image display of one of claim 1-5, wherein,

Described display gray scale obtains in received image signal by adding a random value, and described random value is based on that the gray-scale value of described received image signal produces.

8. image display, a kind of ON/OFF pattern of one group of son by constituting a field, each gray level of presentation video is come gray scale images, and this image display comprises:

An input picture converting unit is used for received image signal is converted to image information;

A sub-field information generation unit is used for producing display message according to the image information from the output of input picture converting unit for each son field; And

An address driver is used for sub-field information generation unit is write image display area for each son display message that produces, wherein,

When described received image signal is represented a graticule or a square pattern, and the high brightness of described pattern and low-light level are differential when very big, described input picture converting unit is provided with a district that is made up of a plurality of adjacent image points according to described received image signal, and replaces described received image signal with its low level of a high position that its high position is respectively described received image signal corresponding to the mutually the same respectively signal of described a plurality of adjacent image points.

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