Color sample and light type estimation method

Abstract

To reduce labor when preparing a colored pattern in advance for estimating the kind of a light source.SOLUTION: The color sample 10 has sample color regions 12B1, 12B2, 12B3, 12B4, 12B5, 12BH, 12RGB, 12V1, and 12V2 corresponding to the observation result of the color of the illumination target 1 illuminated with illumination light L close to any one of a plurality of types of illumination light (CIE LED illumination conditions). However, in the irradiation target 1, the absorbance of blue, green, and yellow light is higher than the absorbance of red and purple light, and the reflectance of red and purple light is higher than the reflectance of blue, green, and yellow light. Further, the illumination light has types BH and RGB in which the relative brightness takes the maximum value in red, types V1 and V2 in which the relative brightness takes the maximum value in purple, and types B1, B2, B3, B4, and B5 in which the relative brightness takes the maximum value in blue.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to estimating the type of light source. [Background technology]

[0002] Conventionally, the following methods have been known: (1) a pair of colored sheets are prepared that appear to be the same color when illuminated with a predetermined type of light source (e.g., a D65 light source, a high color rendering daylight fluorescent lamp, etc.) but appear to be different colors when illuminated with other light sources; (2) the colored sheets are illuminated with the light source whose type is to be estimated; and (3) by observing the color of the colored sheets, it is possible to estimate whether the light source whose type is to be estimated is the predetermined light source (see, for example,

[0007] of Patent Document 1 and Figures 3 and 5 of Patent Document 12).

[0003] It is also known to grasp color changes when a printed matter is observed under a non-standard light source (see, for example, Patent Document 3), and to adjust the chromaticity of output light using two of the red, green, and blue light sources and a white light source (see, for example, Patent Document 4).

[0004] Furthermore, the measurement of the total spectral emissivity coefficient of an object is also known (see, for example, the abstract of Patent Document 5). [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 7-248259 [Patent Document 2] Japanese Patent Application Laid-Open No. 2007-159051 [Patent Document 3] Japanese Patent Application Laid-Open No. 2008-224236 [Patent Document 4] Japanese Patent Publication No. 2022-175497 [Patent Document 5] Japanese Patent Application Laid-Open No. 2015-52616 Summary of the Invention [Problem to be solved by the invention]

[0006] However, according to the above-mentioned conventional light source estimation method, a pair of colored sheets must be prepared for each type of light source, which is labor-intensive.

[0007] Therefore, an object of the present invention is to reduce the effort required to prepare colored patterns in advance in order to estimate the type of light source. [Means for solving the problem]

[0008] The color sample of the present invention is a color sample having a sample color area that corresponds to the observed color of an irradiated object irradiated with illumination light that is close to any one of a plurality of types of illumination light, wherein the irradiated object has a higher absorptance of blue light than that of red and purple light, and a higher reflectance of red and purple light than that of blue light, and the illumination light is configured to include a type whose relative luminance has a maximum value in red, a type whose relative luminance has a maximum value in purple, and a type whose relative luminance has a maximum value in blue.

[0009] The color sample constructed as described above has a sample color region. The sample color corresponds to the observed color of an irradiated object irradiated with illumination light similar to one of a plurality of types of illumination light. The irradiated object has a higher absorptance for blue light than for red and purple light, and a higher reflectance for red and purple light than for blue light. The illumination light includes a type whose relative luminance has a maximum value in red, a type whose relative luminance has a maximum value in purple, and a type whose relative luminance has a maximum value in blue.

[0010] In addition, the color sample of the present invention may be such that the irradiated body has a higher absorptance for blue, green, and yellow light than for red and purple light, and a higher reflectance for red and purple light than for blue, green, and yellow light.

[0011] In addition, in the color sample of the present invention, the illumination light may be B1, B2, B3, B4, B5, BH, V1, V2 and RGB under CIE LED illumination conditions, and the types whose relative luminance has a maximum value in red may be BH and RGB, the types whose relative luminance has a maximum value in purple may be V1 and V2, and the types whose relative luminance has a maximum value in blue may be B1, B2, B3, B4 and B5.

[0012] In addition, in the color sample of the present invention, the irradiated body may have a filter and a white member in contact with the filter, the white member reflects the irradiated light that has passed through the filter, and the filter may have a higher transmittance for red and purple light than the transmittance for blue light, and a higher absorbance for blue light than the absorbance for red and purple light.

[0013] In the color sample according to the present invention, the white member may be ceramic.

[0014] In the color sample according to the present invention, the white member may be paper.

[0015] In the color sample according to the present invention, the white member may be a plurality of sheets of paper stacked together.

[0016] In the color sample according to the present invention, the filter may be an optical filter for wavelength calibration.

[0017] The color sample according to the present invention may have areas of the sample color for all of the plurality of types.

[0018] The light type estimation method of the present invention includes an illumination step of illuminating an irradiated object with a light source that emits illumination light similar to any one of a plurality of types of illumination light, and a type estimation step of estimating the type of illumination light that is closest to the illumination light based on the observation results of the color of the irradiated object, wherein the irradiated object has a higher absorptance of blue light than that of red and purple light, and a higher reflectance of red and purple light than that of blue light, and the illumination light is configured to include a type whose relative luminance has a maximum value in red, a type whose relative luminance has a maximum value in purple, and a type whose relative luminance has a maximum value in blue.

[0019] According to the light type estimation method configured as described above, the illumination step includes illuminating an irradiated object with a light source that emits illumination light similar to one of a plurality of types of illumination light. The type estimation step includes estimating the type of illumination light that is closest to the illumination light based on the color observation results of the irradiated object. Note that the irradiated object has a higher absorptance for blue light than for red and purple light, and a higher reflectance for red and purple light than for blue light. The irradiated object includes a type of illumination light whose relative luminance has a maximum value in red, a type whose relative luminance has a maximum value in purple, and a type whose relative luminance has a maximum value in blue.

[0020] In addition, in the light type estimation method of the present invention, the type estimation step may be configured to estimate the type of illumination light based on the sample color area of ​​the present invention that is closest to the observed color of the illuminated object. [Brief explanation of the drawings]

[0021] [Figure 1] 1A and 1B are a front view and a plan view, respectively, of an irradiation object 1 according to an embodiment of the present invention. [Figure 2] 1 is a diagram for explaining light reflected and light absorbed by an irradiation object 1 according to an embodiment of the present invention. [Figure 3] 1 is a plan view of a color sample 10 according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0022] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0023] FIG. 1 is a front view (FIG. 1(a)) and a plan view (FIG. 1(b)) of an irradiated object 1 according to an embodiment of the present invention. FIG. 2 is a diagram for explaining light reflected and light absorbed by the irradiated object 1 according to an embodiment of the present invention. FIG. 3 is a plan view of a color sample 10 according to an embodiment of the present invention.

[0024] A light source 2 (see FIG. 1(a)) emits irradiation light L. The irradiation light L illuminates an object 1 to be irradiated.

[0025] 3, color sample 10 has sample color areas 12B1, 12B2, 12B3, 12B4, 12B5, 12BH, 12V1, 12V2, and 12RGB. For example, color sample 10 is a single sheet on which the above sample color areas are printed.

[0026] The above sample colors are colors that correspond to the results of visually observing the color of the irradiated object 1 irradiated with the irradiation light L. What the sample colors are will be described later in "<About sample colors>".

[0027] The illumination light L is similar to one of a plurality of types of illumination light, including a type whose relative luminance has a maximum value in red, a type whose relative luminance has a maximum value in purple, and a type whose relative luminance has a maximum value in blue.

[0028] For example, the illumination light is B1, B2, B3, B4, B5, BH, V1, V2, and RGB, which are CIE LED illumination conditions. The following table shows each of the CIE LED illumination conditions (type of illumination light) and the wavelength bands (of light) where their relative luminance is at its maximum.

[0029] [Table 1] Referring to the table above, when the illumination light is CIE LED lighting conditions, the types whose relative luminance has a maximum value in red are BH and RGB, the types whose relative luminance has a maximum value in purple are V1 and V2, and the types whose relative luminance has a maximum value in blue are B1, B2, B3, B4, and B5.

[0030] In the color sample 10, sample color areas 12B1, 12B2, 12B3, 12B4, 12B5, 12BH, 12V1, 12V2 and 12RGB exist for all of the multiple types of illumination light (B1, B2, B3, B4, B5, BH, V1, V2 and RGB).

[0031] Furthermore, the irradiated object 1 has a higher absorptance for blue (and green and yellow) light than for red and violet light. Furthermore, the irradiated object 1 has a higher reflectance for red and violet light than for blue (and green and yellow) light.

[0032] Referring to FIG. 1, an object to be illuminated 1 has a filter 1a and a white member 1b in contact with the filter 1a.

[0033] The filter 1a has a higher transmittance for red and violet light than for blue (and green and yellow) light. The filter 1a also has a higher absorption rate for blue (and green and yellow) light than for red and violet light. An example of such a filter 1a is a wavelength calibration optical filter (for example, a HOYA V10 filter).

[0034] The transmittance of the filter 1a is, for example, (1) The blue wavelength (430-490 nm, e.g., 442 nm, 477 nm) has a minimum value. (2) A minimum value in the green (490-550 nm, e.g., 529 nm) (3) Yellow (550-590 nm, e.g., 577-587 nm) has a minimum value. (4) The maximum value is in the red (640-770 nm, e.g., 653 nm, 708 nm), (5) It has a maximum in purple (380-430 nm, e.g., 412 nm).

[0035] Of the light incident on filter 1a, most of the light that does not pass through filter 1a is absorbed by filter 1a without being scattered or reflected. Thus, as an example, filter 1a described above absorbs most of the blue, green, and yellow light.

[0036] The white member 1b is, for example, ceramic or paper (it may be multiple sheets of paper). Preferably, the white member 1b has a transmittance of approximately 0% for light incident on the white member 1b (however, no fluorescent whitening agent is used).

[0037] 2, the white member 1b reflects the irradiated light L that has passed through the filter 1a. In FIG. 2, R, V, B, G, and Y represent the red light component, violet light component, blue light component, green light component, and yellow light component of the irradiated light L, respectively.

[0038] The white member 1b reflects the irradiated light L (mainly the red light component R and the violet light component V) that has passed through the filter 1a.

[0039] <About the sample colors> As described above, the sample color is a color that matches the results of visually observing the color of the irradiated object 1 irradiated with the irradiation light L. Therefore, the results of visually observing the color of the irradiated object 1 irradiated with the irradiation light L will be described with reference to FIG.

[0040] However, for convenience of illustration, FIG. 2 shows that the blue light component B, the green light component G, and the yellow light component Y of the irradiated light L are all absorbed by the filter 1a, and the red light component R and the violet light component V of the irradiated light L are all transmitted through the filter 1a.

[0041] In reality, a small portion of the blue light component B, green light component G, and yellow light component Y of the irradiated light L is transmitted through the filter 1a, and a small portion of the red light component R and violet light component V of the irradiated light L is absorbed by the filter 1a.

[0042] (1) If the sample color is reddish When RGB is incident on filter 1a as illumination light L, most of the blue light component B and green light component G of illumination light L are absorbed by filter 1a. On the other hand, most of the red light component R passes through filter 1a, is almost entirely reflected by white member 1b, and most of it passes through filter 1a again to be captured by the observer's naked eye. However, since filter 1a cannot absorb all components of RGB other than the red light component R, the observed color is not completely red, but rather a reddish color (sample color region 12RGB).

[0043] Furthermore, when BH is incident on filter 1a as illumination light L, most of the blue light component B of illumination light L is absorbed by filter 1a. On the other hand, most of the red light component R passes through filter 1a, is almost entirely reflected by white member 1b, and most of it passes through filter 1a again to be captured by the observer's naked eye. However, since filter 1a cannot absorb all components of BH other than the red light component R, the observed color is not completely red, but rather a reddish color (sample color region 12BH).

[0044] Note that RGB and BH are not exactly the same colors, so the color of the sample color area 12RGB is different from the color of the sample color area 12BH (the former appears redder).

[0045] (2) If the sample color is purplish When V1 is incident on filter 1a as illumination light L, most of the illumination light L except for the violet light component V is absorbed by filter 1a. On the other hand, most of the violet light component V passes through filter 1a, is almost entirely reflected by white member 1b, and most of it passes through filter 1a again to be captured by the observer's naked eye. However, since filter 1a cannot absorb all components of V1 except for the violet light component V, the observed color is not completely purple, but rather a purplish color (sample color region 12V1).

[0046] Furthermore, when V2 is incident on filter 1a as illumination light L, most of the illumination light L except for the violet light component V is absorbed by filter 1a. On the other hand, most of the violet light component V passes through filter 1a, is almost entirely reflected by white member 1b, and most of it passes through filter 1a again to be captured by the observer's naked eye. However, since filter 1a cannot absorb all components of V2 except for the violet light component V, the observed color is not completely purple, but rather a purplish color (sample color region 12V2).

[0047] Note that V1 and V2 are not exactly the same color, so the color of the sample color area 12V1 is different from the color of the sample color area 12V2 (the former appears more purple).

[0048] (3) When the sample color is low-saturation red to green When B1 is incident on filter 1a as illumination light L, most of the blue light component B of illumination light L is absorbed by filter 1a. However, B1 also contains color components other than the blue light component B, so some of these color components pass through filter 1a, are almost entirely reflected by white member 1b, and some still pass through filter 1a to be captured by the observer's naked eye. Since there are not many color components other than the blue light component B in B1 to begin with, the observed color is low in saturation (sample color region 12B1).

[0049] The same applies when any of B2, B3, B4, and B5 is incident on the filter 1a as the irradiated light L.

[0050] Furthermore, since B1, B2, B3, B4, and B5 are not completely the same color, the color of the sample color areas 12B1 to 12B5 is a low-saturation red to green color.

[0051] Next, a light type estimation method using the illuminated object 1 according to the embodiment of the present invention will be described.

[0052] First, the object 1 is illuminated by the light source 2 that emits illumination light L that is close to any one of a plurality of types of illumination light.

[0053] Furthermore, the color of the object 1 to be illuminated is visually observed, and the type of illumination light that is closest to the illumination light L is estimated based on the observation results.

[0054] For example, if the observed color is reddish, it can be estimated that the type of illumination light closest to the illumination light L is RGB or BH. If it appears redder, it can be estimated that the type of illumination light is RGB. Otherwise, it can be estimated that the type of illumination light is BH.

[0055] For example, if the observed color is purplish, it can be estimated that the type of illumination light closest to the illuminating light L is V1 or V2. If it appears more purplish, it can be estimated that the type of illumination light is V1. Otherwise, it can be estimated that the type of illumination light is V2.

[0056] For example, if the observed color is low in saturation, it can be estimated that the type of illumination light closest to the irradiated light L is one of B1 to B5. Depending on whether it is closer to red, red, or green, the type of illumination light can be narrowed down to one of B1 to B5.

[0057] The above-described light type estimation method does not use the color sample 10. However, by comparing the (color of) the observation result with the (color of) each sample color area of ​​the color sample 10, the type of illumination light can be estimated based on the latter that is closest to the former.

[0058] For example, if the (color of) the observation result is closest to (the color of) sample color region 12BH among (the colors of) each sample color region of color sample 10, it can be estimated that the type of illumination light is BH.

[0059] According to the embodiment of the present invention, the effort required to prepare a colored pattern in advance in order to estimate the type of light source 2 can be reduced.

[0060] That is, according to the embodiment of the present invention, once the irradiation object 1 (filter 1a and white member 1b) is prepared, there is no need to prepare a colored pattern in advance.

[0061] Furthermore, according to an embodiment of the present invention, even when preparing an irradiated object 1 and a color sample 10, it is sufficient to prepare one area (such as 12B1) of the color sample 10 for each type of illumination light, thereby reducing the effort required by about half compared to preparing a set of two colored sheets for each type of light source. [Explanation of symbols]

[0062] 1 Irradiated object 1a Filter 1b White material 2 light source 10 color swatches 12B1, 12B2, 12B3, 12B4, 12B5 Sample color area 12BH, 12RGB sample color area 12V1, 12V2 Sample color area L irradiation light LED lighting conditions for B1, B2, B3, B4, B5 CIE LED lighting conditions for BH, RGB CIE LED lighting conditions for V1 and V2 CIE R: Red light component of irradiated light L V: violet light component of irradiated light L B: Blue light component of irradiated light L G: Green light component of irradiated light L Y Yellow light component of irradiated light L

Claims

1. A color sample having a sample color area corresponding to the observation result of the color of an irradiated object irradiated with irradiation light similar to any one of a plurality of types of illumination light, The irradiated object is The absorption rate of blue light is higher than that of red and violet light, The reflectance of red and violet light is higher than that of blue light, The illumination light is The type in which the relative luminance is maximum in red, The type whose relative luminance reaches its maximum value in purple, A type in which the relative luminance has a maximum value in blue. Color sample.

2. 2. The color sample according to claim 1, The irradiated body is The absorption of blue, green, and yellow light is higher than that of red and violet light, A color swatch that reflects more red and purple light than blue, green, and yellow light.

3. 2. The color sample according to claim 1, The illumination light is B1, B2, B3, B4, B5, BH, V1, V2, and RGB under the CIE LED illumination conditions; The types in which the relative luminance has a maximum value in red are BH and RGB. The types whose relative luminance has a maximum value in purple are V1 and V2. The color samples in which the relative luminance has a maximum value in blue are B1, B2, B3, B4, and B5.

4. 2. The color sample according to claim 1, The irradiated body is A filter, a white member in contact with the filter; and the white member reflects the irradiation light that has passed through the filter; The filter is The transmittance of red and violet light is higher than that of blue light, The absorption rate of blue light is higher than that of red and violet light. Color sample.

5. 5. The color sample according to claim 4, A color sample in which the white member is ceramic.

6. 5. The color sample according to claim 4, A color sample in which the white member is paper.

7. 7. The color sample according to claim 6, A color sample in which the white member is a plurality of sheets of paper stacked together.

8. 5. The color sample according to claim 4, A color sample in which the filter is an optical filter for wavelength calibration.

9. 2. The color sample according to claim 1, The sample color area exists for all of the plurality of types. Color sample.

10. an illumination step of illuminating an object to be illuminated with a light source that emits illumination light similar to any one of the plurality of types of illumination light; a type estimation step of estimating the type of the illumination light that is closest to the irradiation light based on the observation result of the color of the irradiated object; Equipped with The irradiated object is The absorption rate of blue light is higher than that of red and violet light, The reflectance of red and violet light is higher than that of blue light, The illumination light is The type in which the relative luminance is maximum in red, The type whose relative luminance reaches its maximum value in purple, A type in which the relative luminance has a maximum value in blue. Light type estimation method.

11. The light type estimation method according to claim 10, The type estimation step The type of the illumination light is estimated based on the sample color area according to any one of claims 1 to 9, which is closest to the observed color of the illuminated object. Light type estimation method.

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