WO2001014856A1

WO2001014856A1 - Apparatus and method for capturing and displaying color

Info

Publication number: WO2001014856A1
Application number: PCT/US2000/022355
Authority: WO
Inventors: William G. Reed
Original assignee: Digital Now, Inc.
Priority date: 1999-08-20
Filing date: 2000-08-15
Publication date: 2001-03-01
Also published as: AU6774000A

Abstract

An apparatus and method for capturing visible and non-visible electromagnetic radiation (light) from a source surface (130) and displaying the same radiation, or a proportional quantity of a different radiation, on a second surface (162). The apparatus (100) comprises a lightproof enclosure (102) having an aperture at one end, a light source (106) disposed within the lightproof enclosure (102) opposite the aperture, means (120) for controlling the output intensity of the light source (106), and means (140) for detecting the amount of radiation reflected back from the source surface (130).

Description

APPARATUS AND METHOD FOR CAPTURING AND DISPLAYING COLOR

FIELD OF THE INVENTION The present invention relates generally to the field of color and light reproduction, and more particularly to devices and methods for measuring, capturing and reproducing color and light.

RELATED ART

In certain situations it is desirable to transport or move a sample of a particular color to another location for the purpose of showing the color to another person, or comparing it to or distinguishing it from another color. Such situations arise, for example, during the course of home improvement, remodeling, decorating or construction projects that involve purchasing paint, window treatments or wall-coverings that must match items already in a room. Such situations could also arise when purchasing clothing or decorating accessories.

Occasionally, it is possible to physically move the object containing the color, or an exemplary piece of it, to the location where it needs to be displayed. This will only work, however, if the object of interest is relatively small or can be disassembled into smaller component parts that can be easily carried. But in many situations, it is physically impossible, dangerous, or otherwise impractical to transport the object of interest, or an exemplary piece of it, to the location where the color needs to be examined.

A current way of dealing with this problem is to produce small transportable cards containing samples of colors contained on the object of interest. These cards are normally called swatches. People are accustomed, for example, to leaving paint stores and kitchen and bath remodeling stores with a handful of paint, cabinet and counter-top swatches to show to a spouse or to compare to objects already located in the room being remodeled. That solution works fine when the time, space and resources are available to manufacture and distribute the swatches. But in many situations, the person who needs to transport and display the color does not have the time, materials, expertise or equipment to manufacture or purchase swatches.

Another popular way of dealing with the problem of transporting color is to photograph the object. Typically this is done with a Polaroid® or 35mm camera. But this method also has some significant drawbacks. Sometimes the object is so small that can be very difficult or impossible to get close enough to the object to fill the camera's field of view and still keep the object in focus. Even if a properly focused photograph can be taken, the color of the object in the photograph will appear considerably different depending on any number of important factors, such as the time of day if the object is outside, the ambient light in the room if the object is inside, or the bounce of the camera's flash off the surface of the object. The color of the object as it appears in the photograph may be washed out, too dark or entirely obscured by the flash. Thus, taking a photograph may not produce color of sufficient accuracy for comparison.

In addition to variable and unpredictable lighting conditions, the appearance of color in a photograph can be severely distorted due to the age of the photograph — color photographs tend to fade over time — , as well as the quality and sophistication of the particular camera, developing process and printing equipment used to make the photograph. Photographs of the same object taken at different points in time, using different cameras and/or different developing processes and printing equipment will usually yield extremely inconsistent results. There are a number of color-measuring devices — densitometers, spectrophotometers and colorimeters, for example — that are sometimes used to determine whether two colors are the same. Not only are these devices very expensive — they typically cost $1000 and up — they do not work well for transporting or moving color to another location because they do not capture or reproduce color — at least not without additional equipment. These devices only measure color. Thus, if a spectrophotometer reading taken from a surface A at a location X equals the spectrophotometer reading taken from a surface B at a location Y, then you know that surface A and surface B are the same color (assuming, of course, that the spectrophotometer is well-calibrated and in good working order). But if the goal is to display at location Y the color of surfaces situated at location X, and there are no surfaces at location Y that are identical or at least comparable in color to the surfaces at location X, then none of these color-measuring devices would be of any use.

Accordingly, there is a need recognized in a number of different industries, such as the home improvement, construction and remodeling businesses, for example, for an easy and inexpensive way to capture one or more colors at one location, and then reproduce and display the same or substantially the same colors at another location, possibly at a much later point in time.

In certain situations, it is also desirable to capture non-visible light radiation, such as infrared or ultraviolet radiation, at one location and reproduce it at another location. Such a situation could arise, for example, in scientific experiments involving the ultraviolet detection capabilities of insects. In these experiments, the ultraviolet light level is captured in the field is reproduced in a laboratory. In other types of experiments involving fiber optics, it is useful to capture the infrared light level of the output of a fiber optic cable and reproduce it at a location where an analytical measuring device is located.

At times it is desirable to convert non- visible electromagnetic radiation to a proportional quantity of visible light in a predictable and accurate manner. For example, if a device is known, suspected or even capable of emitting dangerous electromagnetic radiation at a wavelength not visible to the human eye (such as x-rays, ultraviolet or gamma rays, for instance), it would be extremely useful to capture and measure such radiation and then display a proportional quantity of visible radiation (say, red light, for example) as a warning. The resulting visible light would not only indicate the presence of non- visible radiation, but could also give an accurate reproduction of the strength of the radiation.

Accordingly, there is also a need recognized by inventors in several industries, including but not limited to medicine, telecommunications and scientific research, for a simple and inexpensive way to capture non- visible electromagnetic radiation and produce a proportional quantity of visible radiation.

SUMMARY OF THE INVENTION

The present invention is directed to an apparatus and method for capturing visible and non-visible electromagnetic radiation emanating from a source (or surface) at one location and reproducing or displaying the same or substantially the same radiation at another location or on another surface. In one aspect of the present invention, a color capture and display device is provided. The device comprises a lightproof enclosure having an aperture at one end and a light source, disposed within the lightproof enclosure and opposite the aperture. The light source is configured to direct at least three colors of light visible to the human eye through the aperture and onto a surface. The device also includes means, coupled to the light source, for controlling the output intensity of the colors of light, and means for detecting the amount of light reflected back from the surface. In a preferred embodiment, the means for detecting the amount of light reflected back from the surface comprises a photodiode configured to transform light entering the enclosure into electrical signals, and means for converting the electrical signals into digital data.

In the preferred embodiment, the light source is configured to direct at least three colors of light because of the tri-stimulus nature of human vision, which requires that three sets of cells in the eye (called cones) be stimulated in order to produce an accurate representation of any single color. However, one of skill in the art would appreciate that capturing and redisplaying light of a single wavelength would only require a light source capable of producing that wavelength and a photodiode capable of detecting only that wavelength. For example, if the source surface only reflected light of pure red, a light source only capable of producing pure red and a photodiode only capable of detecting pure red, would be sufficient for purposes of capturing and displaying that light. Thus, a person of skill in the art would recognize that such an embodiment is considered within the scope of the present invention.

The preferred embodiment of the present invention also comprises a microprocessor for controlling the output intensity of the light. The preferred embodiment may further comprise a translucent removable cover for the aperture, the surface of which can be used to display color.

In another aspect of the present invention, a method or process for capturing and displaying color is provided. The method comprises the steps of: measuring a source surface reflectance for each of three or more colors of visible light; illuminating a target surface with the same three or more colors of light; and adjusting the output intensity of those three or more colors of light until the target surface reflectance for the three or more colors is equal to or substantially equal to the source surface reflectance for those three colors, thereby making the target surface appear to be the same color as the source surface.

In another embodiment of the present invention, the adjusting step comprises adjusting the output intensity of the color of the at least three colors of light until the relative difference between the target surface reflectance for each of the at least three colors is equal to or substantially equal to the relative difference between the source surface reflectance for each of the at least three colors, whereby the target surface appears to be the same color as the source surface.

In a further aspect of the present invention, the output intensity of the three or more colors of light is adjusted in one or more of the following ways: (a) modulating the pulse width while holding power and frequency constant; (b) modulating the frequency while holding pulse width and power constant; or (c) modulating the power while holding pulse width and frequency constant.

In a further aspect of the present invention, the source surface reflectance is stored in a storage medium, possibly for later use or processing. In yet another aspect, the source surface is illuminated with the three or more colors of light prior to measuring its reflectance. In still another aspect, the illumination of the source surface and second surface is accomplished by sequentially exposing the surfaces with each of the three or more colors of light. In a further aspect of the present invention, the output intensity adjustments are successively reduced by half to arrive at an output intensity that causes the reflectance values to equate or substantially equate to the reflectance values of the source surface. And in a still further aspect of the present invention, the output intensity adjustments are successively reduced by half to arrive at an output intensity that causes the ratio of the reflectance values of the target surface to equate to the ratio of reflectance values of the source surface. In yet another aspect of the present invention, a method for synchronizing wavelengths of light reflected from a source surface with wavelengths of light reflected from a target surface, is presented. The method comprises the steps of: measuring a source surface reflectance for each of at least three wavelengths of light; illuminating a target surface with the at least three wavelengths of light; and adjusting the output intensity of the at least three wavelengths until the target surface reflectance for each wavelength is substantially equal to the source surface reflectance for each wavelength. In another aspect of the invention, the reflectance ratios of the wavelengths of light is used to achieve the same result.

In yet another embodiment of the present invention, a method for capturing non-visible electromagnetic radiation and displaying a proportional quantity of visible electromagnetic radiation is presented. The method comprises the steps of: measuring a source surface reflectance for non-visible electromagnet radiation, illuminating a target surface with visible electromagnetic radiation; and adjusting the output intensity of the visible electromagnetic radiation until the target surface reflectance for the visible electromagnetic radiation is substantially equal to the source surface reflectance for the non-visible electromagnetic radiation. Features and Advantages of the Present Invention

It is a feature of the present invention that visible and non- visible light emanating from one location or from one source, such as a surface, can be captured and displayed at a different location or on a different surface.

It is a further feature of the present invention that the visible and non- visible light of an object can be captured and transported without damaging the object.

It is yet another feature of the present invention that visible and non- visible light can be captured and stored for a long period of time without breaking down, degrading or fading.

It is an advantage of the present invention that it is small, portable and relatively inexpensive compared to other devices or methods for transporting and displaying visible and non-visible light at remote locations.

It is another advantage of the present invention that it does not require a calibrated display device, such as a computer monitor, to reproduce visible and non- visible light.

It is a further advantage of the present invention that the same light sources are used to measure and display light, thereby eliminating drift and calibration problems.

Additional features and advantages of the present invention are set forth in part in the description that follows, and in part are apparent from the description, or may be learned by practice of the invention. The features and advantages of the invention may also be realized and attained by means of the instrumentalities and combinations particularly set out in the appended claims.

BRIEF DESCRIPTION OF THE FIGURES

The accompanying drawings, which are incorporated in and constitute part of the specification, illustrate preferred embodiments of the invention, and, together with the description, serve to explain the principles of the present invention. In the drawings, like reference numbers indicate identical or functionally similar elements. Additionally, the left-most digit(s) of a reference number identifies the drawing in which the reference number first appears.

FIG. 1 depicts a block diagram of a device for capturing and displaying visible and non- visible light according to a preferred embodiment of the present invention. FIG. 2 shows a flow diagram for a method for capturing and displaying visible and non-visible light in accordance with the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Reference will now be made in detail to preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings. Notably, the present invention may be implemented using software, hardware or any combination thereof, as would be apparent to those of ordinary skill in the art, and the figures and examples below are not meant to limit the scope of the present invention or its embodiments or equivalents. Overview of the Present Invention

The present invention measures the reflectance (or reflectivity) of light from a source surface and reproduces that reflectance on a target surface. In a preferred embodiment, red, green and blue light-emitting diodes (LEDs) are used to sequentially illuminate a first (source) surface and a photodiode is used as a sensor to capture and digitize the red, green and blue light reflected back from that first surface. Then a second surface (the target surface) is illuminated with the same three LEDs and the same photodiode is used to capture and digitize the red, green and blue light reflected from the second surface. As the second (or target surface) is being illuminated, the LED pulse widths are adjusted until the reflectance of the second surface is equal to, or substantially equal to, the reflectance of the first surface, thereby "closing the loop" and making the light reflected from the second surface appear to be identical or substantially identical to the light reflected from the first surface. In other words, the surfaces appear to be the same color. In another embodiment, three or more other colors of light, such as cyan, magenta and yellow, are used to illuminate the first and second surfaces and the photodiode captures and digitizes the reflectance of those colors from the surfaces.

Drift and calibration problems are eliminated because both surfaces are illuminated and measured with the same light sources and the same sensor. Thus, the present invention has a tremendous advantage over current methods and devices for capturing and reproducing light that use different light sources and sensors and therefore experience calibration and drift problems. There is a wide range of commercial applications that could significantly benefit from the present invention. With the present invention, for example, it will be much easier to accomplish tasks such as matching paints to existing surfaces, checking production lots of manufactured items, choosing clothing and decorating accessories to match other items of clothes or decoration, etc. For most applications, it is highly desirable to capture and display light visible to the human eye. But there are some applications where it is essential or at least highly desirable to use light that falls outside the visible spectrum, such as infrared or ultraviolet light. One such application would be detecting and displaying the presence and relative strength of a data signal in fiber-optic telecommunications systems.

In a preferred embodiment, the reflectance values are stored in a storage medium, such as a non- volatile memory, for subsequent use or processing. In a further preferred embodiment, a microprocessor is coupled to the photodiodes, LED light sources and storage medium to control the output intensity adjustments or to automate certain production or manufacturing functions.

Detailed Operation of the Present Invention

With reference now to FIG. 1, a block diagram of one embodiment of a color capture and display device 100 in accordance with the present invention is shown. In this example, three colors of light are used to illuminate the first surface and the photodiode 140 measures the reflectance of each of those three colors. It would be apparent to one of skill in art, however, that embodiments that use a different number of colors of light are also considered to be within the scope of the present invention. Another alternative considered to be within the scope of the invention is to use three wavelengths of light not within the visible spectrum.

Color capture and display device 100 is comprised of a lightproof enclosure 102 having an aperture at one end, a light source 104, a microprocessor 120 and a photodiode 140. In the preferred embodiment, the aperture of lightproof enclosure

102 is designed to accommodate pressing color capture and display device 100 against surface 130 in order to capture and display the color reflected from surface 130. Light source 104 is disposed within lightproof enclosure 102 and configured to direct at least three colors of visible light through the aperture in lightproof enclosure 102 and onto surface 130. In the embodiment shown in FIG. 1, light source 104 is comprised of a red light source 106, a green light source 108 and a blue light source 110.

Alternately, light source 104 may be configured as a source of three or more other wavelengths of radiation (instead of red, green and blue light, such as infrared, ultraviolet, etc. Also disposed within lightproof enclosure 102 is a photodiode 140, which senses light reflected from surface 130 and generates electrical signals representing the amount of light detected. Photodiode 140 is coupled via link 141 to an analog-to-digital converter 142, which converts electrical signals received from photodiode 140 into digital data and passes the digital data to microprocessor 120 via link 132. Microprocessor 120 controls the output intensity of light source 104 (red light source 106, green light source 108 and blue light source 110) via link 116. Several methods of controlling the output intensity are available, including but not limited to: (a) modulating the pulse width while holding power and frequency constant; (b) modulating the frequency while holding pulse width and power constant; or (c) modulating the power while holding pulse width and frequency constant. In a preferred embodiment, the adjustments to the output intensities are made by "successive approximation," i.e., reducing the adjustments by increasingly smaller powers of 2, e.g. 64, 32, 16, 8, etc., until the proper reflectance values are recorded. A person of ordinary skill in the art would recognize that the proper intensity values could also be found by making linear changes in output intensity, although doing so might take longer.

In an alternative embodiment, output intensity values are adjusted until the relative differences between reflectance values for the three colors used to illuminate the target surface equate or substantially equate to the relative differences between the reflectance values for the three colors used to illuminate the source surface. Thus, it is not required, for example, that the red, green and blue reflectance values for the target surface equate or substantially equate to the red, green and blue reflectance values of the source surface. The color of the target surface will also appear to be the same as the color of the source surface when the relative differences between the red, green and blue reflectance values for the target surface equate or substantially equate to the relative differences between the red, green and blue reflectance values for the source surface.

Various commercially available microprocessors can be effectively adapted for use in the present invention, including one referred to by model number PIC16C54, manufactured and sold by Microchip Systems, Inc. In the embodiment shown in FIG. 1, microprocessor 120 is also coupled to a storage medium 150 via link 138. The results of reflectance measurements taken by photodiode 140 are stored in storage medium 150 and can be accessed at the appropriate time for subsequent use or processing by microprocessor 120 or other coupled devices (not shown). This allows color capture and display device 100 to display captured colors at a much later point in time. This storage medium 150 is preferably implemented with solid-state semi-conductor memory technology in order to minimize the size of the device, but other forms of memory, such as digital tape, may also be used.

In a preferred embodiment, color capture and display device 100 also comprises a translucent removable cover 160, which can be placed over the aperture in lightproof enclosure 102 for the purpose of serving as a target surface or display screen. When removable cover 160 is in place, and light sources 106, 108 and 110 are activated and adjusted so that their reflectances equal or substantially equal the reflectances of an earlier-sampled surface, the light emanating from light sources 106, 108 and 110 will fall on the inside surface 162 of removable cover 160. This will cause the inside surface of removable cover 160 to appear to the eye to be the same color as the earlier-sampled color. But because removable cover 160 is translucent, the color of its inside surface can be seen on the opposite outside surface 164 too. Thus, all the user has to do is look at the outside surface 164 to observe the earlier-sampled color. In an alternative embodiment, color capture and display device 100 includes an opening or shaft extending through the rear 105 of the color capture and display device 100 to the back end 107 of lightproof enclosure 102. This opening or shaft (not shown in FIG. 1 for brevity) would allow the user to look through the device from the backside and directly observe the inside surface 162 of removable cover 160. With reference now to FIG. 2, a flow diagram 200 for a method or process for capturing and displaying color in accordance with one embodiment of the present invention is shown. First, in a step 202, the reflectance of a source surface (depicted as surface 130 in FIG. 1) for each of three colors of light is measured (by photodiode 140). In a step 204, a target surface — i.e., removable cover 160, for example — is illuminated with the same three colors of light. As would be apparent to one skilled in the art, the target surface is not limited to being part of the device; a separate target surface could also be used. Next, in a step 206, the output intensities of the three colors of light are adjusted so that the reflectance of the target surface equal to, or substantially equal to, the reflectance of the source surface as measured in step 202. In the most preferred embodiment, the output intensity of the illumination of the second surface is adjusted by modulating the pulse widths while holding power and frequency constant. However, as noted above, other methods of adjusting the output intensity are contemplated and within the scope of the invention. The next step, step 208, is to determine whether the target surface reflectance is equal to or substantially equal to the source surface reflectance. How closely the reflectance of the source surface needs to coincide with the reflectance of the target surface, and thus, how much modulation is required, could be readily determined by one skilled in the art based on the application. In some situations, there would understandably be very little tolerance for error in displaying the captured color. Such would be the case, for example, if the goal were to display the exact color of additional paint needed to complete the painting of a continuous wall. This is because having even slightly different colors of paint on the same wall is normally a very noticeable defect. On the other hand, there are some applications where there is significantly more room for error in reproducing the sampled color. For instance, if the goal is to display the color of an adjacent wall while shopping for drapes, it is normally not a serious problem if the colors do not exactly match. As would be apparent to one skilled in the art, the variance between the reflectance of the source surface and the reflectance of the second surface that can be reasonably tolerated is also a function of the processing power of the microprocessor used. The use of a 12-bit analog-to-digital converter to digitize the reflectance to represent the color values, for example, will only distinguish colors that have reflectance values greater than 0.05 percent apart. Thus, two colors having reflectance values less than 0.05 percent apart appear to be the same color when such a 12-bit analog-to-digital converter is used. Distinguishing colors that have reflectance values less than 0.05 percent apart can be achieved, for example, by using a 16-bit analog-to-digital converter or other device with greater resolution.

Continuing with step 208 in flow diagram 200 of FIG. 2, if the answer to the question of whether equality or substantial equality has been reached is "NO," then processing returns to step 206, where additional adjustments to output intensity are made. If, on the other hand, the answer is "YES," then processing ends. The present invention has been disclosed and described herein in what is considered to be its most preferred embodiments. It should be noted that variations and equivalents may occur to those skilled in the art upon reading the present disclosure and that such variations and equivalents are intended to come within the scope of the invention and the appended claims.

Claims

CLAIMS What I claim is:

1. A color capture and display device comprising: a lightproof enclosure having an aperture at one end;

a light source, disposed within said light proof enclosure and opposite said aperture, said light source being configured to direct at least three colors of light visible to the human eye through said aperture and onto a surface ;

means, coupled to said light source, for controlling an output intensity of said at least three colors of light; and

means for detecting an amount of said at least three colors of light reflected from said surface into said lightproof enclosure through said aperture.

2. The device of claim 1 , wherein said means for detecting comprises:

a photodiode, disposed within said light proof enclosure, said photodiode being configured to transform light entering said light proof enclosure through said signals; and

means, coupled to said photodiode, for converting said electrical signals to digital data.

3. The device of claim 1 , wherein said means for controlling comprises a microprocessor.

4. The device of claim 1, further comprising a removable cover coupled to the aperture end of said lightproof enclosure and opposite said light source.

5. The device of claim 4, wherein a portion of said removable cover adjacent to said aperture and exposed to the inside of said lightproof enclosure forms said surface.

6. The device of claim 4, wherein said removable cover is translucent.

7. The device of claim 1, wherein said light source comprises:

a red light source; a green light source; and a blue light source.

8. The device of claim 1, further comprising means for successively reducing changes in said output intensity by half.

9. A device for synchronizing wavelengths of light comprising:

a lightproof enclosure having an aperture at one end;

a light source, disposed within said lightproof enclosure and opposite said aperture, said light source being configured to direct at least three wavelengths of light through said aperture and onto a surface ;

means, coupled to said light source, for controlling an output intensity of said at least three wavelengths of light; and means for detecting an amount of said at least three wavelengths of light reflected from said surface into said lightproof enclosure through said aperture.

10. The device of claim 9, wherein said means for detecting comprises:

a photodiode, disposed within said light proof enclosure, said photodiode being configured to transform light entering said light proof enclosure through said aperture into electrical signals; and

1 1. The device of claim 9, wherein said means for controlling comprises a microprocessor.

12. The device of claim 9, further comprising a removable cover coupled to the aperture end of said lightproof enclosure and opposite said light source.

13. The device of claim 12, wherein a portion of said removable cover adjacent to said aperture and exposed to the inside of said lightproof enclosure forms said surface.

14. The device of claim 12, wherein said removable cover is translucent.

15. The device of claim 9, wherein said light source comprises: a red light source; a green light source; and a blue light source.

16. The device of claim 9, further comprising means for successively reducing changes in said output intensity by half.

17. A color capture and display device comprising: a lightproof enclosure having an aperture at one end;

a light source, disposed within said light proof enclosure and opposite said aperture, said light source being configured to direct a color of light visible to the human eye through said aperture and onto a surface ;

means, coupled to said light source, for controlling an output intensity of said color of light; and

means for detecting an amount of said color of light reflected from said surface into said lightproof enclosure through said aperture.

18. A method for capturing and displaying color, comprising the steps of:

measuring a source surface reflectance for each of at least three colors of light, wherein each of said at least three colors of light is visible to the human eye;

illuminating a target surface with said at least three colors of light; and

adjusting an output intensity of said at least three colors of light until a target surface reflectance for each of said at least three colors of light is substantially equal to said source surface reflectance for each of said at least three colors of light;

whereby said target surface appears to be the same color as said source surface.

19. The method of claim 18, wherein said adjusting step comprises modulating the pulse width of said at least three colors of light while holding power and frequency constant.

20. The method of claim 18, wherein said adjusting step comprises modulating the frequency of said at least three colors of light while holding pulse width and power constant.

21. The method of claim 18, wherein said adjusting step comprises modulating the power of said at least three colors of light while holding pulse width and frequency constant.

22. The method of claim 18, further comprising the step of recording the source surface reflectance in a storage medium.

23. The method of claim 18, further comprising the step of illuminating said source surface with said at least three colors of light prior to said measuring step.

24. The method of claim 23, wherein said step of illuminating said source surface comprises sequentially exposing said source surface with each of said at least three colors of light.

25. The method of claim 23, wherein said step of illuminating said target surface comprises sequentially exposing said target surface with each of said at least three colors of light.

26. The method of claim 18, wherein said step of illuminating said target surface comprises sequentially exposing said target surface with each of said at least three colors of light.

27. The method of claim 18, wherein said adjusting step comprises successively reducing changes in output intensity by half.

28. A method for capturing and displaying color, comprising the steps of:

illuminating a target surface with said at least three colors of light; and

adjusting an output intensity of said at least three colors of light until a relative difference between a target surface reflectance for each of said at least three colors of light is substantially equal to a relative difference between said source surface reflectance for each of said at least three colors of light;

29. The method of claim 28, wherein said adjusting step comprises modulating the pulse width of said at least three colors of light while holding power and frequency constant.

30. The method of claim 28, wherein said adjusting step comprises modulating the frequency of said at least three colors of light while holding pulse width and power constant.

31. The method of claim 28, wherein said adjusting step comprises modulating the power of said at least three colors of light while holding pulse width and frequency constant.

32. The method of claim 28, further comprising the step of recording the source surface reflectance in a storage medium.

33. The method of claim 28, further comprising the said step of illuminating said source surface with said at least three colors of light prior to said measuring step.

34. The method of claim 33, wherein said step of illuminating said source surface comprises sequentially exposing said source surface with each of said at least three colors of light.

35. The method of claim 33, wherein said step of illuminating said target surface comprises sequentially exposing said target surface with each of said at least three colors of light.

36. The method of claim 28, wherein said step of illuminating said target surface comprises sequentially exposing said target surface with each of said at least three colors of light.

37. The method of claim 28, wherein said adjusting step comprises successively reducing changes in output intensity by half.

38. A method for synchronizing wavelengths of light reflected from a source surface with wavelengths of light reflected from a target surface, comprising the steps of:

measuring a source surface reflectance for each of at least three wavelengths of light;

illuminating said target surface with said at least three wavelengths of light; and

adjusting an output intensity of said at least three wavelengths of light until a target surface reflectance for each of said at least three wavelengths of light is substantially equal to said source surface reflectance for each of said at least three wavelengths of light.

39. The method of claim 38, wherein said at least three wavelengths of light are visible to the human eye.

40. The method of claim 38, wherein said adjusting step comprises modulating the pulse width of said at least three wavelengths of light while holding power and frequency constant.

41. The method of claim 38, wherein said adjusting step comprises modulating the frequency of said at least three wavelengths of light while holding pulse width and power constant.

42. The method of claim 38, wherein said adjusting step comprises modulating the power of said at least three wavelengths of light while holding pulse width and frequency constant.

43. The method of claim 38, further comprising the step of recording the source surface reflectance in a storage medium.

44. The method of claim 38, further comprising the step of illuminating said source surface with said at least three wavelengths of light prior to said measuring step.

45. The method of claim 44, wherein said step of illuminating said source surface comprises sequentially exposing said source surface with each of said at least three wavelengths of light.

46. The method of claim 44, wherein said step of illuminating said target surface comprises sequentially exposing said target surface with each of said at least three wavelengths of light.

47. The method of claim 44, wherein said step of illuminating said target surface comprises sequentially exposing said target surface with each of said at least three wavelengths of light.

48. The method of claim 38, wherein said adjusting step comprises successively reducing changes in output intensity by half.

9. A method for synchronizing wavelengths of light reflected from a source surface with wavelengths of light reflected from a target surface, comprising the steps of:

adjusting an output intensity of said at least three wavelengths of light until a relative difference between a target surface reflectance for each of said at least three wavelengths of light is substantially equal to a relative difference between a source surface reflectance for each of said at least three wavelengths of light.

50. The method of claim 49, wherein said at least three wavelengths of light are visible to the human eye.

51. The method of claim 49, wherein said adjusting step comprises modulating the pulse width of said at least three wavelengths of light while holding power and frequency constant.

52. The method of claim 49, wherein said adjusting step comprises modulating the frequency of said at least three wavelengths of light while holding pulse width and power constant.

53. The method of claim 49, wherein said adjusting step comprises modulating the power of said at least three wavelengths of light while holding pulse width and frequency constant.

54. The method of claim 49, further comprising the step of recording the source surface reflectance in a storage medium.

55. The method of claim 49, further comprising the said step of illuminating said source surface with said at least three wavelengths of light prior to said measuring step.

56. The method of claim 55, wherein said step of illuminating source surface comprises sequentially exposing said source surface with each of said at least three wavelengths of light.

57. The method of claim 55, wherein said step of illuminating said target surface comprises sequentially exposing said target surface with each of said at least three wavelengths of light.

58. The method of claim 49, wherein said step of illuminating said target surface comprises sequentially exposing said target surface with each of said at least three wavelengths of light.

59. The method of claim 49, wherein said adjusting step comprises successively reducing changes in output intensity by half.

60. A method of capturing and displaying non-visible electromagnetic radiation as visible electromagnetic radiation, comprising the steps of:

measuring a source surface reflectance for non-visible electromagnet radiation;

illuminating a target surface with visible electromagnetic radiation; and

adjusting an output intensity of said visible electromagnetic radiation until the target surface reflectance for the visible electromagnetic radiation is substantially equal to the source surface reflectance for said non-visible electromagnetic radiation.

61. The method of claim 60, wherein said adjusting step comprises modulating the pulse width of said visible electromagnetic radiation while holding power and frequency constant.

62. The method of claim 60, wherein said adjusting step comprises modulating the frequency of said electromagnetic radiation while holding pulse width and power constant.

63. The method of claim 60, wherein said adjusting step comprises modulating the power of said electromagnetic radiation while holding pulse width and frequency constant.

64. The method of claim 60, further comprising the step of recording the source surface reflectance in a storage medium.

65. The method of claim 60, wherein said adjusting step comprises successively reducing changes in output intensity by half.

66. A method for capturing and displaying a color of light, comprising the steps of:

measuring a source surface reflectance for said color of light;

illuminating a target surface with said color of light; and

adjusting an output intensity of said color of light until a target surface reflectance for said color of light is substantially equal to said source surface reflectance for said color of light;