JP5918993B2 - High chroma color light generation apparatus and color reproduction evaluation method - Google Patents

Description

  The present invention relates to a technique for generating a standard color (color light) required when evaluating or calibrating a color reproduced by a camera, a display, a printer, or the like, and in particular, a color reproduction range. The present invention relates to a high-saturation color light generation apparatus and a color reproduction evaluation method that generate high-saturation color light suitable for color reproduction evaluation of a wide-range camera or the like.

  In recent years, cameras, displays, printers, and the like with a wide color gamut have been developed, and the demand for wide color gamut is increasing. Even in Super High Definition (UHDTV), which is a next-generation television system that exceeds the resolution of HDTV (High Definition Television) represented by HiVision (registered trademark), Rec. Compared to a conventional color gamut called 709, a wide color gamut color system has been proposed in which the saturation of the three primary colors of RGB is set higher.

  In a color reproduction device such as a camera, it is important to perform color reproduction evaluation to determine whether the reproduced color matches the original color, and to calibrate the reproduced color. For color reproduction evaluation and color calibration in cameras that support the conventional color gamut (Rec. 709), a reflective color chart called ColorChecker Classic that has 24 color charts (color patches) (previously “Macbeth”) In the present specification, “Macbeth chart” is generally used as a de facto standard.

  On the other hand, in order to properly perform color reproduction evaluation and color calibration in a camera having a wider color reproduction range than the conventional one, a high saturation color (hereinafter referred to as a standard) in a high saturation color gamut that exceeds the conventional color gamut. This is called “high saturation standard color” as appropriate, but such a high saturation standard color has not been established, and various proposals and attempts have been made.

  For example, in Patent Document 1 below, a transmissive color chart including a transmissive color filter having high saturation as a transmissive color chart is created, and the transmitted color (translucent color filter) of the transmissive color filter is prepared. It has been proposed to use the color of light that passes through a light-transmitting color filter when the light is illuminated as a high saturation standard color. In addition, a reflective color chart with a reflective color chart having higher saturation than the conventional Macbeth chart is created, and the surface color of the reflective color chart (the reflective color chart when the reflective color chart is illuminated) Attempts have also been made to use the color of the light reflected from the light as a high saturation standard color.

JP 2003-172659 A

  In order to generate a high-saturation color (color light) by the conventional method as described above, it is necessary to color the color chart using a color material having a higher saturation than conventional color materials. However, organic pigments known as high-saturation coloring materials generally have low durability, and when such coloring materials are used as coloring materials for color charts, it is difficult to exhibit temporally stable color performance. It becomes.

  The present invention has been made in view of such circumstances, and provides a high saturation color light generation apparatus and a color reproduction evaluation method that can stably generate high saturation color light that can be used as a high saturation standard color. Objective.

In order to solve the above problems, a high-saturation color light generation apparatus according to the present invention includes:
Spectral characteristic setting means for setting a spectral characteristic obtained by squaring the spectral characteristic of the color of the color chart corresponding to a predetermined color gamut as a high-saturation spectral characteristic;
Based on the set the high saturation of the spectral characteristics, by adjusting the intensity of each wavelength component of the source light synthesizing respective wavelength components after adjustment, it has a spectral distribution that correlates with the high saturation of the spectral characteristics, the predetermined Color light generating means for generating high-saturation color light corresponding to a specific color gamut having higher saturation than the color gamut ,
Diffusing and emitting means for diffusing and emitting the generated high saturation color light.

In the high saturation color light generation device according to the present invention, the spectral distribution correlated with the high saturation spectral characteristic may be a spectral distribution obtained by multiplying the spectral distribution of the light source light and the high saturation spectral characteristic.
Further, the color light generation means includes a spectral element that splits the light source light from a white light source into each wavelength component, a wavelength component intensity adjustment element that adjusts the relative intensity of each wavelength component dispersed by the spectral element, And a light guide element that synthesizes the wavelength components from the wavelength component intensity adjusting element.

The color reproduction evaluation method according to the present invention is
A spectral characteristic setting step for setting a spectral characteristic obtained by squaring the spectral characteristic of the color of the color chart corresponding to a predetermined color gamut as a high saturation spectral characteristic;
Based on the set the high saturation of the spectral characteristics, by adjusting the intensity of each wavelength component of the source light synthesizing respective wavelength components after adjustment, it has a spectral distribution that correlates with the high saturation of the spectral characteristics, the predetermined A color light generation step for generating high saturation color light corresponding to a specific color gamut having a higher saturation than the color gamut of the color gamut ;
A diffusion emission step of diffusing and emitting the generated high-saturation color light; and
A color light photographing step of photographing the emitted high saturation color light with a camera to be examined;
A color reproduction evaluation step for evaluating color reproducibility by the test camera by comparing the color data reproduced by the test camera with the color light reproduction of the high saturation color with reference color data of the color light of the high saturation. Are performed in this order for the colors of the color charts.

  The “predetermined color gamut” refers to Rec. A conventional general color gamut such as 709 can be used, but the present invention is not limited to this, and an arbitrary color gamut can be used.

  The “color chart corresponding to the predetermined color gamut” is preferably a standard color chart such as a Macbeth chart color chart used for color reproduction evaluation in a conventional general color gamut. However, the present invention is not limited to this, and any color chart can be used.

  Further, the “spectral characteristic of the color of the color chart” means that, when the color chart is a reflective color chart, the spectral reflectance of the color of the reflective color chart or when the reflective color chart is illuminated. If the color chart is a transmissive color chart, the spectral transmittance of the color of the transmissive color chart, or the transmissive color When the vote is illuminated, the spectral distribution of the color light transmitted through the transmissive color chart can be obtained.

  In addition, the above-mentioned “spectral distribution correlating with the high-saturation spectral characteristic” means a spectral distribution equal to the high-saturation spectral characteristic (the ratio of each wavelength component in the high-saturation spectral characteristic and the ratio of each wavelength component in the correlated spectral distribution) Is a concept including equal spectral distributions).

  According to the high saturation color light generation device and the color reproduction evaluation method according to the present invention, the following effects can be achieved by providing the above-described features.

  That is, the highly saturated color light generated by the present invention has a spectral distribution that correlates with the highly saturated spectral characteristic obtained by squaring the spectral characteristic of the color of the color chart corresponding to the predetermined color gamut. The color light has a high saturation while having the same hue as the vote color. In addition, the color light of high saturation is not generated via a color chart, but is generated by adjusting the intensity of each wavelength component of the light source light and synthesizing the adjusted wavelength components. It is not necessary to color the color chart using a highly saturated color material with low durability.

  Therefore, according to the present invention, it is possible to generate high-saturation color light that can exhibit stable color specification performance, and this high-saturation color light is standard in a high-saturation color gamut that exceeds the conventional color gamut. It can be used as a high saturation standard color.

  In addition, according to the color reproduction evaluation method according to the present invention, a camera with a wide color reproduction range capable of reproducing colors with higher saturation than before by using high saturation color light capable of exhibiting stable color specification performance. Thus, it is possible to appropriately perform color reproduction evaluation such as.

  In particular, if the color chart of each color in a standard color chart such as the Macbeth chart is sequentially used as the color chart that is the basis for setting the high-saturation spectral characteristics, high saturation exceeding the conventional color gamut can be achieved. Also in the color reproduction evaluation in the color gamut, it is possible to obtain the same reliability as the color reproduction evaluation in the conventional color gamut.

It is a figure which shows schematic structure of the high chroma color light generation apparatus which concerns on one Embodiment of this invention. It is a figure which shows schematic structure of the optical system of the color light generation apparatus shown in FIG. It is a block diagram which shows schematic structure of the analysis control apparatus shown in FIG. It is a figure which shows an example of spectral characteristic data. It is a figure which shows an example of the color chart which has the color chart used as the foundation at the time of setting highly desaturated spectral distribution. It is a graph which shows an example of a high saturation spectral characteristic. It is a graph which shows another example of a saturation chromatographic characteristic. It is a graph which shows distribution of the chromaticity point of each color chart of the color chart shown in FIG. It is a graph which shows distribution of the chromaticity point of each highly saturated color light produced | generated by the high chroma color light generation apparatus. It is a graph which shows chromaticity distribution of the pointer color which is a database of the actual surface color. It is a graph which shows an example of the color difference of the color (reproduction color) reproduced with the to-be-tested camera, and its original color (reference color). It is a graph which shows an example of distribution of the chromaticity point of the color (reproduction color) reproduced with the to-be-tested camera, and its original color (reference color) on an xy chromaticity diagram.

  Hereinafter, embodiments of a high saturation color light generation apparatus and a color reproduction evaluation method according to the present invention will be described in detail with reference to the drawings.

<High chroma color light generator>
A high saturation color light generation device 10 shown in FIG. 1 is configured as a color reproduction evaluation system for evaluating a color (reproduction color) reproduced by a camera 70 to be tested. The color light generation device 20, the integrating sphere 30, and An analysis control device 40 is provided.

  The color light generation device 20 corresponds to color light generation means in the present embodiment, and as shown in FIG. 2, a light source 21, a lens 22, a spectroscopic element 23, a wavelength component intensity adjustment element 24, a lens 25, and a light guide. An optical system including the element 26 and the like is provided.

  As the light source 21, a white light source (for example, a D65 light source that outputs light having a correlated color temperature of 6500 K) that includes all wavelength components in the visible light region (for example, 380 to 780 nm) is used. The spectroscopic element 23 includes a reflection type diffraction grating (a transmission type diffraction grating or a prism may be used), and splits light (light source light) incident from the light source 21 through the lens 22 into each wavelength component. Is configured to do.

  The wavelength component intensity adjusting element 24 is configured by a mirror array element (for example, a DMD element manufactured by Texas Instruments) in which a large number of minute movable mirrors are two-dimensionally arranged. Each mirror array of the mirror array element corresponds to each wavelength band when the visible light range is divided into a plurality of wavelength bands having a predetermined wavelength width (for example, 5 nm), and each movable mirror in each mirror array is turned on. The direction of the reflecting surface can be switched between the direction (the direction in which the reflected light enters the lens 25) and the off direction (the direction in which the reflected light does not enter the lens 25). Therefore, for each movable mirror in one mirror row, the intensity of the wavelength component corresponding to the mirror row to be incident on the lens 25 is adjusted by adjusting the ratio of the mirrors facing the on direction and those facing the off direction. The ratio (relative intensity) of each wavelength component can be adjusted by performing this operation on each mirror array.

  The light guide element 26 is composed of an optical fiber, and combines the wavelength components incident from the wavelength component intensity adjusting element 24 via the lens 25 to generate colored light, and guides the colored light to the integrating sphere 30. It has become.

  In addition, as such a color light generation apparatus 20, what is put into practical use as a wavelength programmable light source (model number: OSVISX) manufactured by OneLight, for example, can be used.

  The integrating sphere 30 (see FIG. 1) corresponds to the diffused emission means in the present embodiment. The integrating sphere 30 has a diffuse reflection surface whose inner surface is coated with a white paint such as barium sulfate or titanium oxide, and diffuses and reflects the color light input from the light guide element 26 to thereby distribute the luminance distribution of the color light. And the color light having a uniform luminance distribution is emitted from the output opening 31.

  The analysis control device 40 corresponds to spectral characteristic setting means in the present embodiment, and is an arithmetic processing device such as a computer (notebook personal computer is illustrated in FIG. 1, but is not limited thereto). Not). The analysis control device 40 is configured to set a high saturation spectral characteristic for defining a spectral distribution of high saturation color light generated by the color light generation device 20 and to evaluate color reproducibility by the camera 70 to be tested. As shown in FIG. 3, a spectral characteristic data storage unit 41, a saturation spectral characteristic calculation unit 42, and a color reproduction evaluation unit 43 are provided. The spectral characteristic data storage unit 41, the high saturation spectral characteristic calculation unit 42, and the color reproduction evaluation unit 43 are CPU, ROM, RAM, hardware such as an electronic circuit, and software such as a control program stored in the ROM. It is a functional representation of what is composed of.

  The spectral characteristic data storage unit 41 stores spectral characteristic data (hereinafter, referred to as “basic spectral characteristic data” as appropriate) for setting the above-described high saturation spectral characteristics. In the present embodiment, the spectral reflectance data of the colors of the color charts (color patches) P1 to P24 of the reflective color chart 50 shown in FIG. Data is stored for each color chart P1 to P24 as shown in FIG. 4 (only a part is shown in FIG. 4).

  The color chart 50 shown in FIG. 5 has a standard specification corresponding to the conventional color gamut (Rec. 709), and includes 24-color reflective color charts P1 to P24. The colors of the color charts P1 to P24 are set so as to substantially match the colors of the color charts in the conventional Macbeth chart, and the arrangement order of the colors is the same as that of the Macbeth chart (the color charts P1 to P18 are provided). Coloring and color charts P19 to P24 are achromatic).

Based on the spectral reflectance data of the colors of the color charts P1 to P24 stored in the spectral characteristic data storage section 41, the high-saturation spectral characteristic calculation section 42 corresponds to the color charts P1 to P24 (chromatic color charts P1 to P1). For each color (which may be P18), a saturation spectral characteristic obtained by squaring the spectral reflectance is calculated (when the spectral reflectance is R (λ), {R (λ)} ² is calculated. ). The calculated data of each of the high-saturation spectral characteristics is configured to be stored in the spectral characteristic data storage unit 41. Specific examples of the calculated saturation spectral characteristics are shown in FIGS. In addition, the numerical value of the vertical axis | shaft in the graph shown in FIG.6 and FIG.7 has shown the reflectance.

FIG. 6 shows the spectral reflectance of the color (green) of the color chart P14 of the color chart 50 (see FIG. 5) (curve C ₁ indicated by a one-dot chain line in the figure) and the color chart P14 calculated based on this. A saturation spectral characteristic obtained by squaring the spectral reflectance of the color (curve C ₂ indicated by a broken line and curve C ₃ indicated by a solid line in the figure) is shown. The curve C ₂ shows the shape when the spectral reflectance of the color of the color chart P 14 (the numerical value on the vertical axis of the curve C ₁ ) is simply squared, and the curve C ₃ is the peak of the curve C ₂ . height to match the height of the peak in the curve C _1, is obtained by a constant multiple of the curve C ₂ in the vertical axis direction. The curves C ₂ and C ₃ appear to have different shapes as graphs, but are equal to each other as graphs showing the ratio (relative intensity) of each wavelength component. Comparing curve C ₁ and curve C _3, towards the curve C ₃ than the curve C ₁ is, has become steeper slope in the vicinity of the peak wavelength, from this, the color spectral reflectance of the color chart P14 It can be seen that the saturation spectral characteristic obtained by squaring 2 is higher in saturation than the spectral reflectance of the color of the color chart P14.

FIG. 7 shows the spectral reflectance of the color (blue flower) of the color chart P5 of the color chart 50 (see FIG. 5) (curve C ₁₁ shown by a one-dot chain line in the figure), and the color chart P5 calculated based on this. color high saturation of spectral characteristics of the spectral reflectance obtained by the square of (the curve C ₁₃ indicated by the curve C ₁₂ and solid shown with broken lines in the _drawing) is shown. A curve _{C 12,} the color spectral reflectance of the color chart P5 (the numerical value of the ordinate of the curve _{C 11)} and merely shows a squared shape if, curve _{C 13} is maximum in the curve _{C 12} the height of the peak (peak on the longer wavelength side), to match the height of the largest peak in the curve C ₁₁ (peak of the same long wavelength side), is obtained by a constant multiple of the curve C ₁₂ in the vertical axis direction . Although the curves C ₁₂ and C ₁₃ appear to be different in shape as graphs, they are equal to each other as graphs showing the ratio (relative intensity) of each wavelength component. Comparing the curves C ₁₁ and the curve C _13, towards the curve C ₁₃ than the curve C ₁₁ is the slope in the vicinity of the two peak wavelengths and becomes both steep, Therefore, the color chart P5 color It can be seen that the high saturation spectral characteristic obtained by squaring the spectral reflectance has a characteristic that the saturation is higher than the spectral reflectance color of the color chart P5.

  The color reproduction evaluation unit 43 (see FIG. 3) evaluates the color reproducibility of the test camera 70 by comparing the reproduction color data of the color light imaged by the test camera 70 with the reference color data. It is configured.

  The analysis control device 40 calculates each of the high saturation spectral characteristics based on the colors of the color charts P1 to P24 calculated by the high saturation spectral characteristic calculation unit 42, and the spectral distribution of the color light generated by the color light generation device 20. Set sequentially to define.

The color light generation device 20 correlates with the highly saturated spectral characteristic by adjusting the ratio (relative intensity) of each wavelength component of the light source light in the wavelength component intensity adjusting element 24 based on each set highly saturated spectral characteristic. For example, a spectral characteristic obtained by multiplying the spectral distribution of the light source light and the highly saturated spectral characteristic (the spectral distribution of the light source light is P (λ), and the highly saturated spectral characteristic is {R (λ)} ² . High-saturation color light having a spectral characteristic of P (λ) × {R (λ)} ² is generated for each of the set high-saturation spectral characteristics. The generated high-saturation color lights are diffused in the integrating sphere 30 and the luminance distribution is made uniform, and then emitted from the output opening 31.

<High chroma color chromaticity point>
The chromaticity points (chromaticity coordinates) of the color charts P1 to P24 of each color of the color chart 50 described above are shown in FIG. 8 on the xy chromaticity diagram of the XYZ color system defined by the International Commission on Illumination (CIE). Distributed. On the other hand, the chromaticity points of the high-saturation color light generated by the high-saturation color light generation device 10 of this embodiment are distributed as shown in FIG. 9 on the xy chromaticity diagram. The chromaticity points shown in FIGS. 8 and 9 are obtained by calculation under the spectral distribution of the D65 light source based on the color data described in Reference Document 1 below.
Reference 1: Noboru Ota Basics of Color Reproduction Engineering Corona Company 1997

  As shown in FIG. 8, the chromaticity points of the color charts of the respective colors in the color chart 50 are distributed in the color gamut (smaller triangular area in the figure) in the conventional HDTV. On the other hand, as shown in FIG. 9, the chromaticity points of the high-saturation color light generated by the high-saturation color light generation apparatus 10 are in a region where some of the chromaticity points exceed the HDTV color gamut. It can be seen that it is widely distributed within the wide color gamut (larger triangular area in the figure) proposed by the next generation UHDTV as a whole. For this reason, each high saturation color light generated by the high saturation color light generation device 10 is used for color reproduction evaluation in a television camera or the like as a color light representing a color corresponding to a wide color gamut proposed in the next generation UHDTV. Is possible.

  FIG. 10 shows the chromaticity distribution of a pointer color that is an existing surface color database. Referring to the chromaticity distribution of the pointer color, the chromaticity point of each high saturation color light generated by the high saturation color light generation device 10 is a distribution of existing colors rather than the chromaticity point of the color chart of each color of the color chart 50. It is understood that it represents.

  The high saturation color light generation apparatus 10 of the present embodiment generates color light having the same spectral characteristics as the colors of the color charts P1 to P24 of the color chart 50 (hereinafter, referred to as “standard saturation color light” as appropriate). Is also possible. In this case, instead of the above-described high saturation spectral characteristics, the spectral reflectances of the colors of the color charts P1 to P24 are used as the spectral characteristics for defining the spectral distribution of the color light generated by the color light generation device 20. You only have to set it.

  In addition, when generating color light with standard saturation and color light with high saturation, it is preferable to adjust the brightness of the generated color light so that the brightness (intensity) of both color lights is substantially equal to each other. For example, in order to make the brightness of the standard chroma color light corresponding to the color of the color chart P14 and the brightness of the high chroma color light, the intensity of the wavelength component that becomes the peak wavelength in the spectral characteristics of the color of the color chart P14 becomes standard chroma. And adjusting so that the color light of high degree and the color light of high saturation are substantially equal to each other. Similarly, in order to equalize the brightness of the standard chroma color light and the high chroma color light corresponding to the color chart P5, the intensity of the wavelength component having the maximum peak wavelength in the spectral characteristics of the color chart P5 color is set. The standard saturation color light and the high saturation color light are adjusted so as to be substantially equal to each other. It is possible to similarly adjust the colors of other color charts.

<Color reproduction evaluation method>
Hereinafter, a color reproduction evaluation method using the above-described high saturation color light generation apparatus 10 will be described.

<Setting the device>
As shown in FIG. 1, the integrating sphere 30 of the high-saturation color light generation device 10 is arranged in front of the test camera 70 so that the test camera 70 can capture the color light emitted from the output opening 31 of the integrating sphere 30. To do. At that time, the angle of view and the viewing distance at the time of shooting are adjusted so that the shading of the lens of the camera 70 to be examined does not affect the analysis.

  In this embodiment, the color reproduction evaluation of the test camera 70 is performed by analyzing image data captured by the test camera 70 in the analysis control device 40. Instructions to the analysis control device 40 are given via an input device (not shown) such as a keyboard and a mouse, and images taken by the camera 70 to be tested, results of color reproduction evaluation, etc. are displayed on the analysis control device 40. It is displayed on the screen.

<Procedure for color reproduction evaluation>
(1) In the analysis control device 40, spectral characteristics obtained by squaring the spectral characteristics of the color of a predetermined color chart (for example, the color chart P1) among the color charts P1 to P18 of the color chart 50 are expressed as high-saturation spectroscopy. Set as a characteristic (spectral characteristic setting step).

  (2) Based on the saturation saturation spectral characteristics set by the analysis control device 40, the color light generation device 20 adjusts the intensity of each wavelength component of the light source light and synthesizes the adjusted wavelength components, thereby Color light with high saturation having spectral characteristics obtained by multiplying the spectral distribution and the saturation spectral characteristics is generated (color light generation step).

  (3) The highly saturated color light generated by the color light generation device 20 is diffused in the integrating sphere 30 and emitted from the output opening 31 (diffusion emission step).

  (4) The high-saturation color light emitted from the output opening 31 of the integrating sphere 30 is photographed by the test camera 70 (color light photographing step).

  (5) The analysis control device 40 compares the reproduced color data of the high saturation color light imaged by the camera 70 with reference color data of the high saturation color light (for example, the chromaticity point shown in FIG. 9) ( For example, the color reproducibility by the camera 70 is evaluated by obtaining the color difference between the two (color reproduction evaluation step).

  (6) Steps (1) to (5) above are sequentially repeated for the colors of the color charts P1 to P18 of the color chart 50.

  The high-saturation color light generation device 10 generates standard chromatic color light having the same spectral characteristics as the colors of the color charts P1 to P24 of the color chart 50, and uses the standard chromatic color light, the above (1) to (1) to (1)- You may make it evaluate the color reproducibility by the to-be-tested camera 70 by the procedure similar to the step of (6). In this case, the color reproduction evaluation regarding the colors of the achromatic color charts P19 to P24 is performed using the standard chroma color light, and the high chroma color light generates only the color lights corresponding to the chromatic color charts P1 to P18. Thus, it may be used for color reproduction evaluation of chromatic colors in a high-saturation color gamut.

FIG. 11 shows the colors of color light of high saturation (hereinafter referred to as “reproduced colors” as appropriate) reproduced by the test camera 70 when the color lights of high saturation are photographed by the test camera 70 and their original colors. An example of the color difference from the following (hereinafter referred to as “reference color” where appropriate) is shown. The horizontal axis of the graph shown in FIG. 11 represents the numbers (1 to 24) of the color charts P1 to P24 of the color chart 50, and the vertical axis represents the value of CIE94 color difference (ΔE ^* ₉₄ ).

  Further, in FIG. 12, on the xy chromaticity diagram of the XYZ color system, the chromaticity point of the reproduction color (indicated as “reproduction chromaticity point” in the figure) and the chromaticity point of the reference color (see “in the figure” 2 is a graph plotting chromaticity points. The numbers (1-19, 24) shown in the graph of FIG. 12 correspond to the numbers of the color charts P1 to P24 of the color chart 50.

<Proof of color reproduction>
When calibrating the color reproduced by the camera 70, for example, the coefficient of a 3 × 3 matrix that determines the color reproduction characteristics of the camera 70 is set to minimize the color difference between the reproduced color and the reference color. Optimize to be. Usually, in this optimization process, the above-described color reproduction evaluation is performed many times, and the color reproduction evaluation value when optimized is used as the color reproduction performance of the camera 70 to be tested. As a method for optimization, for example, the Nelder-Mead simplex method (see References 2 and 3 below) can be used.

Reference 2: Nelder, JA and R. Mead, "A Simplex Method for Function Minimization," Computer Journal, Vol. 7, p. 308-313, 1965.
Reference 3: Dennis, JE Jr. and DJ Woods, "New Computing Environments: Microcomputers in Large-Scale Computing," edited by A. Wouk, SIAM, 1987, pp. 116-122.

<Change of mode>
As mentioned above, although embodiment of this invention was described, this invention is not limited to the above-mentioned embodiment, It is possible to change an aspect variously.

  For example, the high saturation color light generation apparatus 10 uses the spectral reflectance of the color chart color of the color chart 50 as the spectral characteristics of the color chart color. It is also possible to use the spectral distribution of each color light reflected from each color chart when it is illuminated with the light as the spectral characteristics of the color of the color chart. In addition, when each color chart is a transmissive color chart, the spectral transmittance of the color of each color chart and the spectral distribution of the color light transmitted through each color chart when each color chart is illuminated with standard light It can also be used as a spectral characteristic of the vote color.

Also, when the ideal spectral distribution that the generated high-saturation color light should have, for example, the spectral distribution of the light of the D65 light source is P _D65 (λ), and the spectral reflectance of the color of the color chart is {R (λ)} ² , P _D65 (λ) × {R (λ)} ² is set in advance, and the color light generating device 20 is configured so that the spectral distribution of the color light with high saturation actually generated matches the ideal spectral distribution. In the wavelength component intensity adjusting element 24, the ratio (relative intensity) of each wavelength component of the light source light may be adjusted. In this case, the spectral distribution measurement means for measuring the spectral distribution of the high-saturation color light that is actually generated, or the actual spectral distribution is compared with the ideal spectral distribution by comparing the measured actual spectral distribution with the ideal spectral distribution. It is preferable to provide a feedback mechanism such as a comparison / adjustment unit that adjusts to approach the distribution.

  Further, in the high saturation color light generation device 10 described above, the integrating sphere 30 is used as a diffusion emitting means for diffusing and emitting the color light generated by the color light generation device 20, but a fly eye, a rod lens, a diffusion plate, etc. Other optical elements may be used as the diffuse emission means.

  Further, the high saturation color light generation apparatus 10 is configured to generate and output high saturation color light one by one. For this reason, there is an advantage that there is no need to consider the effect of glare (leakage of light from adjacent color charts), which is a concern when each color chart of the color chart 50 is photographed at one time. It takes time to shoot. Therefore, it is possible to arrange a plurality of high-saturation color light generation devices 10 so that high-saturation color light generation devices 10 generate different colors of high-saturation color light, and can shoot them all at once.

  In the present invention, the spectral characteristic obtained by squaring the spectral characteristic of the color of the color chart corresponding to the predetermined color gamut is set as the high saturation spectral characteristic, but the spectral characteristic of the color of the color chart is “2”. The spectral characteristic obtained by raising the power to other numerical values (eg, any constant a satisfying 1 <a ≦ 3 or 1.7 ≦ a ≦ 2.3) may be set as the high saturation spectral characteristic. Is possible.

DESCRIPTION OF SYMBOLS 10 High chroma color light generation apparatus 20 Color light generation apparatus 21 Light source 22, 25 Lens 23 Spectrometer 24 Wavelength component intensity adjustment element 26 Light guide element 30 Integrating sphere 40 Analysis control apparatus 50 Color chart 70 Test camera P1-P24 Color chart

Claims (4)

Spectral characteristic setting means for setting a spectral characteristic obtained by squaring the spectral characteristic of the color of the color chart corresponding to a predetermined color gamut as a high-saturation spectral characteristic;
Based on the set the high saturation of the spectral characteristics, by adjusting the intensity of each wavelength component of the source light synthesizing respective wavelength components after adjustment, it has a spectral distribution that correlates with the high saturation of the spectral characteristics, the predetermined Color light generating means for generating high-saturation color light corresponding to a specific color gamut having higher saturation than the color gamut ,
Diffusing and emitting means for diffusing and emitting the generated high saturation color light; and
A high-saturation color light generation device comprising:   The high saturation color light generation device according to claim 1, wherein the spectral distribution correlated with the high saturation spectral characteristic is a spectral distribution obtained by multiplying the spectral distribution of the light source light and the high saturation spectral characteristic. . The colored light generating means is
A spectroscopic element that splits the light source light from the white light source into each wavelength component;
A wavelength component intensity adjusting element that adjusts the relative intensity of each wavelength component dispersed by the spectroscopic element;
The high saturation color light generation device according to claim 1, further comprising: a light guide element that synthesizes the wavelength components from the wavelength component intensity adjustment element. A spectral characteristic setting step for setting a spectral characteristic obtained by squaring the spectral characteristic of the color of the color chart corresponding to a predetermined color gamut as a high saturation spectral characteristic;
Based on the set the high saturation of the spectral characteristics, by adjusting the intensity of each wavelength component of the source light synthesizing respective wavelength components after adjustment, it has a spectral distribution that correlates with the high saturation of the spectral characteristics, the predetermined A color light generation step for generating high saturation color light corresponding to a specific color gamut having a higher saturation than the color gamut of the color gamut ;
A diffusion emission step of diffusing and emitting the generated high-saturation color light; and
A color light photographing step of photographing the emitted high saturation color light with a camera to be examined;
A color reproduction evaluation step for evaluating color reproducibility by the test camera by comparing the color data reproduced by the test camera with the color light reproduction of the high saturation color with reference color data of the color light of the high saturation.
The color reproduction evaluation method is characterized in that the color reproduction is performed in this order for the colors of the color charts.