WO2001016930A1

WO2001016930A1 - Method and device for controlling a colour display with not more than one control element per pixel

Info

Publication number: WO2001016930A1
Application number: PCT/DE2000/001232
Authority: WO
Inventors: Pascal Lefevre; Dirk Stockhusen; Stephan Windisch
Original assignee: Siemens Aktiengesellschaft
Priority date: 1999-09-01
Filing date: 2000-04-19
Publication date: 2001-03-08

Abstract

Disclosed is a method and a device for controlling a colour display (1) with not more than one control element per pixel. A pixel value (4) corresponding an image information and being related to a pixel respectively is stored in an image memory (3). Said value corresponds to an associated colour value (FW1 - FW4) of a colour set (FSD - FSN) consisting of several colour values (FW1 - FW4). A colour set memory (7) contains at least two colour sets (FSD - FSN). A colour set (FSD - FSN) is selected therefrom and is transmitted into the colour value register (5). The image is displayed on the basis of said colour set (FSD - FSN).

Description

description

METHOD AND DEVICE FOR CONTROLLING A COLOR DISPLAY WITH AT LEAST ONE CONTROL ELEMENT PER IMAGE POINT The invention relates to a method and a corresponding device for controlling a color display with at most one control element per image. Such control elements are generally electrically controlled elements in which an electrical property changes an optical property of the element, such as polarization, transmission or fluorescence.

The so-called liquid crystal displays (LCD ^x s) are widespread, in which a liquid crystal is located between two glass plates and a corresponding electrical field is built up at the respective pixel by appropriate contacts, which ensures that the liquid crystal is aligned at this point. The polarization can thus be changed for each pixel via the control element. This local change in polarization is converted into a

Transmission change implemented by appropriate polarization filters are attached to the glass plates. In the case of a black and white display, different gray levels are generated at the individual pixels in this way. Since the polarization of the liquid crystal also depends on the wavelength, certain additional foils are used in a black and white display in order to filter out this wavelength dependency again.

In more complex color displays, there are three different control elements for the primary colors red, green and blue for each pixel, with which the intensity is regulated separately for each of these primary colors. Any color can be created by mixing these three primary colors.

In addition, there are less expensive, simple color displays with only one control element per pixel CO CO)) P ¹ P ¹ cπ o Cn o cn o C

N z Φ ro OJ P- 03 l-i t, tr Φ m Pf P- CΛ yQ d P- P- 1 tr 3 Φ O P- Φ P- PJ o cn rt d:

> Q H p tu yQ Hi P- rt Φ P- P tr rt d P φ a Φ P- Φ o ^ cn Φ Φ P- • Hi cn tr 3 rt ω l-i a Φ Φ 3 φ Φ rt

O- P- 1 O 3 Φ yQ P- ι-i KP P- π PJ Tl öd Φ OJ H li <P CΛ Φ rt P- Q p. p 0 ⁾ P- P- rt C- P- φ n Φ φ PJ Φ yQ 3 π o P- σ tl Φ 3 tr JHH d ι- (

Φ er at O PJ ^ _* HZ tr tr Hi Φ p φ ∑; • Ö Φ PH Tl P ⁾ vQ s Φ P pd P cn tr Tl P ⁾ ι- (Φ φ P-

Tl rt- l-f p rt P- rt f "l-i N cn H P- ö

0> CΛ rt s P Φ P> n tr \ Ό rt Pf P P- f Ό rt d tr P_ z φ PJ CΛ er P a £ M Φ z P- φ P- OP α Ό z φ Φ Φ 3 P- d cn φ CΛ P- o P Φ φ o CΛ π p ts OH Ό E tr P PJ f tr rt φ yQ ≤ rt P ^J 1 φ li L Φ ^ r + Φ Tl P- 3 P- Φ PJ ö ι- < φ P op OJ Φ φ Φ Φ ^ P- rt P- p. O aa P, P- cn td P- P- CΛ PP tr tt Φ P- tl ζ tl <Ό CΛ CΛ Φ rt

CΛ CL s: yQ 3 P "Φ φ P- P ^J φ Tl T p. H

Φ Φ a cn P- α φ P ⁾ P- O PJ O

Tl P h rt tr * cn P Φ ι- (^ P ι- (P CΛ D rt H π TJ ω • 3 P T3

H ω Φ 0 ⁾ Ö φ P- φ <<d J Φ tr P- 1-1 iQ 1 P- P- tι td Φ P- ö φ PP li s: φ Φ 50 oa rt Φ P, φ P- P -> QP

Φ a ^ Q P ≤ tr Φ cn ^ Q CΛ ι- (φ P cn d Z

H Ό P- - §J Φ cn Ό Φ n φ Z P Φ rt d cn P H tr d <! H φ ιQ P-

Φ P rt a P- ≤ φ P- P P- ι-i cn CΛ

H Pf Φ Φ cn P- O ζ Φ rt φ CΛ rt ≤ Φ

Φ rt ι-f H rt a P tr P- α Φ ι- (Ό Φ P

^ Q Z cn Φ a Φ Φ Φ l-i h α ι- (

P- φ ^ Q Hi 3 tι P CΛ CΛ d P- rt tr n H Φ φ C- N • Φ o rt P p, Φ rt rt P 0 π cn α p> P tr d ^ Q Φ f P-

Φ Φ rt OJ O tl P- Hi J to cn ι-f P cn d LJ. <r_> (U: 3 Tl φ Φ α rt Ό Λ Ό Φ φ OP ⁾ PH P- P- d ti φ a 3 tr α li h- ¹ Φ P ⁾ Φ φ

Φ P P- P- Φ PJ CΛ Φ tr P- φ Λ HP ¹

P- a o P 3 P rt P s: o P CΛ cn rt cn

3 tr Φ tl Φ tr rt φ Z

Φ a rt ι- (ω rt a o l-i Φ cn tr J Φ

Φ • P- Φ P- rt P Ό PJ P- tr P- cn 3 co t ⁾ φ d Φ H d P yQ cn

T rt α tf P cn Φ Hi P ⁾ : φ φ

PJ 3 d Ό tr * tt) α "" l-i O H CΛ

P Hi d o P- Hi) tr Φ Ό <

P H3 Φ P ö PJ Z d φ P- φ P- d π f 1 a o CΛ P P P- φ t> φ tr rt 50 1 tr tr rt Φ n ι- (

Q P- N tr S Φ Φ d σ tr s: Φ K P P- Hi Φ Φ

Φ • P- _^ «Φ P-

HPP rt

J o tv> P ¹ P ¹ cπ o cπ o Cπ o Cπ

The selected color set is preferably transferred from the color set memory to the usual color value register of the display controller, so that a commercially available or only slightly modified controller can be used here, in which either the voltage values associated with the color values themselves or a corresponding jump address are used in coded form are stored in a voltage value table in the color value register. In principle, however, the controller can also directly access the corresponding area of the color set memory in which the desired color set is stored.

In a particularly preferred exemplary embodiment, the color set that was selected for the first time in a representation on the display is stored for a particular image. When the same image is displayed again, this color set is automatically selected again, so that this image is always displayed with the same color set until the user deliberately assigns a different color set to this image.

At the factory, there is advantageously at least one standard color set in the color set memory which is always used in the representation of the customary user interface. Of course, it is also possible for different standard color sets to be stored in the color set memory for different operating states.

In addition, several different color sets can be specified at the factory, from which the user can choose.

In particular, certain color sets can be present for certain types of images. For example, the device can have a switch or button for this purpose, which can be used to switch between a color set for photos, one for graphics, one for writing and one for the normal user interface. and can be jumped here. In particular, further subdivisions are also possible, such as within the "Photos" category according to a red-based color set for portraits, a green-based color set for landscape images and a blue-based color set for technical photos.

When the display of an image with a specific, individually selected color set is terminated, the standard color set of the respective one is preferably restored automatically

Operating state selected. This means that if you return from the display of a photo in the normal user interface, the color value register is automatically switched to the default values.

In a further advantageous exemplary embodiment, the device has means for generating an individual color set by selecting individual color values and for storing the color set in the color set memory. In particular, this can be a device with which individual color values stored in the color value register can be changed and the color set thus changed is then transferred to the color set memory. The change in the individual color values stored in the color value register can be carried out while an image is being displayed, so that the respective effect becomes visible online when a color value is changed.

In another exemplary embodiment, the device has an interface with which externally generated color sets can be transferred to the color set memory.

The color set memory can preferably be arranged in an exchangeable memory carrier, for example a chip card. This can be a storage medium that contains a certain number of predefined color sets, by selecting the storage medium other color sets of the device for display control are made available.

The device can be an independent control module, for example a modified one

Display controller, act that is used in any device as a separate component for controlling the display. In particular in the case of smaller devices with a color display, for example mobile telephones, other communication terminals or PDAs ^λ s, various components of the device can also be distributed in the device. Here, for cost and space reasons, it is advisable to implement at least some of the functional units of the device in software, for example in the CPU of the device. Interfaces and other components that the device already has for other purposes can also be used in order to minimize the costs of producing the device.

With mobile phones, it is particularly useful that the

Color set memory is a special area on the chip card of the mobile phone. In this way, it is possible in particular for different users of the same mobile telephone with different chip cards to use their own individual color sets, which are stored on their personal chip card.

The invention is explained in more detail below with reference to the accompanying drawing, wherein the features described there may also be essential to the invention individually or in other combinations with one another.

The figure shows a simple schematic block diagram of a mobile phone with the display control according to the invention. The display 1 of the mobile phone is controlled as usual by a driver 2. This driver 2 receives the image information from an LCD RAM 3, which for each pixel of the color display 1, a pixel value 4 coded digitally in two bits is stored.

Each pixel value 4 corresponds to a color value FW1-FW4 of a color value register 5, the data of which also from

Driver 2 are queried. Depending on the controller type, these color values FW1 - FW4 are either already digitized voltage values with which the corresponding color tones are generated, or are jump addresses in a voltage value table. Based on this data, the driver 2 provides a voltage for each pixel or for the respective control element of the pixel of the display 1, on the basis of which the liquid crystal at the respective position of the LCD ^x s is polarized accordingly. Each voltage value corresponds to a precisely defined polarization value and thus to a specific color within a color table. The driver 2, the LCD RAM 3 and the color value register 5 are components of a display controller 13.

The driver 2 and the LCD-RAM 3 are connected to a CPU 11 of the device via a bus system. The other components usually present in a mobile phone are also connected to this bus, which are shown in the figure for the sake of simplicity only as a common memory and peripheral block 12.

In addition, according to the invention, the mobile telephone has a color set memory 7, in which, in addition to a standard color set FSD, there is space for a plurality of further color sets FS1-FSN, each of which consists of four color values FW1-FW4 in the present exemplary embodiment. Some of these color sets FS1-FSN have already been inserted into the memory 7 at the factory, so that the user can freely choose from these color sets FSD-FSN. However, it is also possible for the user to create color sets himself and to store them in the free memory locations of the color set register 7. This Color set memory 7 is also connected to the bus system. In one exemplary embodiment, the color set memory 7 is located on the chip card of the mobile phone.

In an exemplary embodiment (not shown), the mobile telephone additionally has an interface via which different color sets FS1-FSN can be loaded into the color set memory 7 by an external device. This can also be an infrared interface or a serial or parallel output, which may already be present on the mobile phone.

To select a color set FSD - FSN from the color memory 7, the controller 13 of the mobile telephone, which in addition to the driver 2, the LCD RAM 3 and the color value register 5 also contains other conventional components, has a selection device 8, which is also via the bus from the CPU 11 is controlled. This selection device 8 determines which color set FSD - FSN is transferred to the color value register 5, so that the image information from the LCD RAM 3 is displayed on the basis of this color set FSD to FSN.

This selection device 8 can, of course, also be implemented in terms of software in the CPU 11. Since the color value register 5 is also connected to the bus, the color set FSD-FSN can be transferred from the color set memory 7 m to the color value register 5 instead of via lines 9, which are provided specifically for this purpose, and also via the bus.

Individual color values FW1-FW4 of the color value register 5 can also be changed by the CPU 11 via the bus while an image is being shown on the display 1, provided that the mobile phone is in a specific operating mode for this purpose. The color set FS1-FSN selected in this way can then be stored in a free memory location of the color set memory 7 either via the bus or via special lines 10 via the selection device 8. A memory area of the mobile phone also stores the specific picture for which a color set FSD - FSN has already been selected. As soon as this image is transferred back to the LCD-RAM 3 for display on the display 1, this is recognized by a corresponding control device, for example the CPU 11, and a corresponding control command is passed on to the selection device 8, so that the color set FSD associated with the image - FSN is transferred to the color value register 5. The image is then automatically displayed with the previously selected color set. Of course, the selection device 8 can also have a corresponding memory, in which case the automatic recognition of the color set associated with the image can take place in the selection device 8 itself.

In an exemplary embodiment not shown, the mobile telephone additionally has a button or switch with which a specific set of colors can be selected for certain image types via the selection device 8. For example, the button can be used to set whether the picture to be displayed is a portrait, a landscape picture, a technical picture or a graphic. Accordingly, a color set based on red, green or blue or a color set consisting of different colors is then selected.

The mobile telephone can also be set so that when a picture is returned with a specially selected color set FS1-FSN, back into the normal standard user interface, the associated standard color set FSD is also automatically loaded into the color value register 5.

The keys or switches mentioned for controlling the various options, for selecting or storing a color set FSD-FSN or individual color values FW1-FW4 are in the exemplary embodiment described Softkey buttons to which various functions can be assigned using standard menu navigation.

The number of color values in the color value register and in one color set is of course not limited to four. Depending on the selection of the register or the controller, fewer or more color values can be made available in a color set.

Claims

claims

1. Method for controlling a color display (1) with at most one control element per pixel, in which a pixel value (4) is stored for each pixel in an image memory (3) in accordance with the image information, which pixel value (FW1-FW4) is one corresponds to several color values (FWl - FW4) of existing color set (FSD - FSN), one color value (FWl - FW4) corresponding to a certain parameter for the control element, characterized in that from a color set memory (7) which has at least two color sets (FSD - FSN), a color set (FSD - FSN) is selected and the image information based on this color set (FSD - FSN) is shown in the display (1).

2. The method according to claim 1, characterized in that the selected color set (FSD - FSN) is transferred from the color set memory (7) into a color value register (5), and from a display driver (2) for each pixel from the

Image memory (3) and the color value register (5) determine the associated color value (FW1-FW4) and a control parameter corresponding to this color value level (6) is transferred to the respective control element of the pixel.

3. The method according to claim 1 or 2, characterized in that a color set (FSD - FSN) has several shades of the same color.

4. The method according to any one of claims 1 to 3, characterized in that for a particular image is saved, which color set (FSD - FSN) is selected for a display on the display (1), and this is automatically displayed when the same image is displayed again Color set (FSD - FSN) is selected.

5. The method according to any one of claims 1 to 4, characterized in that when displaying an image, individual color values (FW1 - FW4) stored in the color value register (5) are changed and the color set (FSD - FSN) generated in this way in the color set memory (7) is saved.

6. The method according to any one of the preceding claims, characterized in that a color set (FSD - FSN) via an interface from an external device to the

Color set memory (7) is transmitted and stored there.

7. The method according to any one of the preceding claims, characterized in that a certain color set (FSD - FSN) is selected for a certain image type.

8. The method according to any one of the preceding claims, characterized in that a standard color set (FSD) is stored in the color set memory (7) for a predetermined operating state.

9. The method according to any one of the preceding claims, characterized in that when the display of an image with a certain individually selected color set (FSD - FSN) is terminated automatically

Standard color set (FSD) of the respective operating state is selected.

10. Device for controlling a color display (1) with at most one control element per pixel, with one

Image memory (3) in which a pixel value (4) is stored for each pixel in accordance with image information, and with a memory in which an associated color value (FW1-FW4) is stored for each pixel value (4), characterized by a

Color set memory (7), which has at least two color sets (FSW - FW4) consisting of several color values (FSD - FSN) contains, and means for selecting a color set (FSD - FSN) from the color set memory (7), and means for displaying the image information in the display (1) on the basis of the selected color set (FSD - FSN).

11. The device according to claim 10, characterized by a color value register (5), means for transferring the selected color set (FSD - FSN) from the color set memory (7) m the color value register (5), and a display driver (2) which for each pixel the image memory (3) and the color value register (5) determine the associated color value (FW1 - FW4) and transmit a control parameter corresponding to this color value (FW1 - FW4) to the respective control element of the pixel.

12. The apparatus of claim 10 or 11, characterized in that a color set (FSD - FSN) has several hues of the same color.

13. Device according to one of claims 10 to 12, characterized by means for storing the color set (FSD - FSN) selected for a representation of a specific image on the display (1), and for automatically selecting the same color set (FSD - FSN) in one redisplay of the same image.

14. Device according to one of claims 10 to 13, characterized by means for generating a color set (FS1 - FSN) by selecting individual color values (FW1 - FW4).

15. The device according to one of claims 10 to 14, characterized in that the means for generating a color set (FS1 - FSN) have a device for changing individual color values (FW1 - FW4) stored in the color value register (5).

16. The apparatus of claim 14 or 15, characterized by means (10) for storing a generated color set (FS1 - FSN) in the color set memory (7).

17. Device according to one of claims 10 to 16, characterized by an interface for transmitting an externally generated color set (FSD - FSN) in the color set memory (7).

18. Device according to one of claims 10 to 17, characterized in that the color set memory (7) is arranged in an exchangeable storage medium of the device.

19. The apparatus according to claim 18, characterized in that the exchangeable storage medium is a chip card.

20. Device with a color display (1) and a device according to one of ^' claims 10 to 19.

21. The device according to claim 20, characterized in that the device is a communication terminal.