JP6658517B2 - Optical characteristic measuring device and optical characteristic measuring method - Google Patents

Description

  The present invention relates to an optical characteristic measuring device and an optical characteristic measuring method for measuring predetermined optical characteristics such as luminance, color and gloss, and more particularly to an optical characteristic measuring device and an optical characteristic measuring method capable of changing a measurement angle.

  In recent years, for example, in various industrial fields such as painting, molding, printing, textile, and agriculture, management of predetermined optical characteristics such as luminance, color, and gloss of a product has been emphasized. As devices for measuring the predetermined optical characteristics, for example, optical characteristic measuring devices such as a luminance meter, a spectral colorimeter, a colorimeter (color difference meter), and a gloss meter are known, and one of them is, for example, a patent. There is a two-dimensional colorimeter disclosed in Document 1.

  The two-dimensional colorimeter disclosed in Patent Document 1 includes a beam splitter that splits light from a sample into a first optical path and a second optical path, and a position through which the light guided to the first optical path passes. And first, second, and third optical filters whose spectral transmittances approximate color matching functions of a predetermined three-dimensional color system, and passing through the first, second, and third optical filters. Two-dimensional light receiving detecting means for receiving the measured light at a plurality of measuring points on the sample surface, and spectral detecting means for detecting a spectral distribution of light guided to the second optical path from a specific point among the measuring points And a tristimulus value calculating means for calculating the tristimulus values of the three-dimensional color system based on the detected spectral distribution; and the calculated tristimulus values and the two-dimensional light reception detection means at the specific point. Using the relationship with the detection results, And a calculating means for calculating the tristimulus values from the detection results of the two-dimensional light receiving detection means. In such a two-dimensional colorimeter, the calculating means uses the relation between the tristimulus value and the detection result of the two-dimensional light reception detecting means at the specific point to calculate the two-dimensional colorimeter for the measurement points other than the specific point. Since the tristimulus value is calculated from the detection result of the two-dimensional light reception detection means, the detection result of the two-dimensional light reception detection means having relatively low accuracy can be corrected with the tristimulus value having relatively high accuracy. The above measurement points can be accurately measured with a simple configuration.

  By the way, as in the two-dimensional colorimeter disclosed in Patent Literature 1, when two first and second spectrometers having different precisions for measuring optical characteristics are provided, for example, the measurement purpose and There is a demand to change the ratio between the measurement angle of the first spectrometer and the measurement angle of the second spectrometer according to the use of the apparatus.

  For example, in the measurement of the brightness distribution of the liquid crystal display, the center of the screen of the liquid crystal display is spot-measured (spot measurement) at a measurement angle of 1 ° by the first spectrometer, and the entire screen of the liquid crystal display is measured by the second spectrometer. Is two-dimensionally measured at a measurement angle of 10 °. On the other hand, in the measurement of the brightness distribution of a display character on an instrument panel (instrument panel, dashboard) of a car, the center of the display character is spot-measured by a first spectroscopic measurement unit at a measurement angle of 1 ° (spot measurement). ), And the entire instrument panel is two-dimensionally measured by the second spectrometer at a measurement angle of 20 °. In order to realize the measurement of the luminance distribution of the liquid crystal display and the measurement of the luminance distribution of the display character on the instrument panel by using one optical characteristic measuring device, the measurement angle of the first spectrometer and the measurement angle of the second spectrometer are measured. It is necessary to change the ratio with the measurement angle. However, conventionally, for example, as in the two-dimensional colorimeter disclosed in Patent Document 1, the ratio is fixed, and the two measurements cannot be realized by one optical property measuring device as it is.

JP-A-6-201472

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an optical characteristic measuring device and an optical characteristic measuring method capable of changing a measurement angle.

  An optical characteristic measuring apparatus and an optical characteristic measuring method according to the present invention spectrally measure light to be measured by first and second spectrometers with different precisions from each other, and based on the first and second measurement results. A predetermined optical characteristic of the measured light is obtained, and at least one of the first and second measurement angles in the first and second spectrometers can be changed by a measurement angle variable optical system. . Therefore, such an optical characteristic measuring apparatus and optical characteristic measuring method can change the measurement angle.

  The above and other objects, features and advantages of the present invention will become apparent from the following detailed description and the accompanying drawings.

It is a figure showing composition of an optical characteristic measuring device in an embodiment. FIG. 3 is a diagram illustrating, as a typical example, the polarization dependence of an incident angle of an aluminum mirror. FIG. 3 is a diagram illustrating a configuration of a second spectrometer in the optical characteristic measuring device. FIG. 9 is a diagram for explaining the spectral responsivity of an optical filter in the second spectrometer. FIG. 3 is a diagram for explaining an operation of a measurement angle variable optical system in the optical characteristic measuring device. FIG. 4 is a diagram for explaining luminance distribution measurement by the optical characteristic measuring device. It is a figure showing composition of a modification in the optical property measuring device. FIG. 5 is a diagram for explaining a relationship between a first area measured at a first measurement angle of a first spectrometer and a two-dimensional sensor of a second spectrometer.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In each of the drawings, components denoted by the same reference numerals indicate the same components, and the description thereof will be omitted as appropriate. In this specification, a generic name is denoted by a reference numeral with a suffix omitted, and an individual configuration is denoted by a reference numeral with a suffix.

  FIG. 1 is a diagram illustrating a configuration of an optical characteristic measuring device according to an embodiment. FIG. 2 is a diagram showing, as a representative example, the polarization dependence of an aluminum mirror on the incident angle. The horizontal axis in FIG. 2 is the incident angle, and the vertical axis is the reflectance. Rp is a reflection characteristic of P-polarized light, Rs is a reflection characteristic of S-polarized light, and R is an average reflection characteristic of Rp and Rs. FIG. 3 is a diagram illustrating a configuration of a second spectroscopic measurement unit in the optical property measurement device. FIG. 3A shows a second spectrometer of the first embodiment, FIG. 3B shows a second spectrometer of the second embodiment, and FIG. 3C shows a second spectrometer of the third embodiment. FIG. 4 is a diagram for explaining the spectral responsivity of the optical filter in the second spectrometer. FIG. 4A shows a case of the CIE color matching function, and FIGS. 4B and 4C show other cases. Each horizontal axis in FIGS. 4A to 4C is a wavelength expressed in nm, and each vertical axis in FIGS. 4A to 4C indicates responsivity. The responsivity indicates how much output there is for a certain input.

  The optical characteristic measuring device D in the present embodiment is, for example, a device that measures predetermined optical characteristics such as luminance, color, and gloss, such as a luminance meter, a spectrocolorimeter, a colorimeter (color difference meter), and a gloss meter. is there. As an example, in the present embodiment, a case will be described below in which the optical property measurement device D is a colorimeter that measures the color of light to be measured as predetermined optical characteristics. As described above, the predetermined optical characteristic may be, for example, a luminance meter for measuring luminance, or may be, for example, a gloss meter for measuring gloss.

  An optical characteristic measuring device D as a colorimeter of this example includes, for example, as shown in FIG. 1, a first spectrometer 1, a second spectrometer 2, a measurement angle variable optical system 3, a control process This embodiment includes a unit 4 and a branching mirror 5, and in the present embodiment, further includes a light receiving optical system 6, an aperture stop 7, an input / output unit 8, and a storage unit 9.

  The light receiving optical system 6 receives the measurement target light emitted from the measurement area SP, and forms an image (first image) IM1 of the measurement target at a predetermined position P1 via the aperture stop 7 and the branching mirror 5. And an optical system such as an objective lens for converging the received light to be measured. The light receiving optical system 6 includes one or a plurality of optical elements such as an optical lens. In the example shown in FIG. 1, the light receiving optical system 6 has a positive refractive power (optical power, the reciprocal of the focal length) as a whole, and is a cemented lens of a biconvex positive lens and a meniscus lens convex on the image side. It is provided with. The light to be measured may be a light source to be measured arranged in the measurement area SP and light emitted from the light source (light of the light source itself). The light emitted from the light source may be reflected light reflected by the object.

  The aperture stop 7 is a member that defines the size of a light beam that passes through the aperture stop 7 (a light beam size, for example, a light beam diameter). The aperture stop 7 is, for example, a plate-shaped member having a through hole and formed of a material having a light-shielding property with respect to a wavelength range of light to be measured. The size of the through hole is set according to the size of the light beam passing through the aperture stop 7. The aperture stop 7 is arranged at a predetermined position close to the branch mirror side.

  The splitting mirror 5 is disposed in the light beam of the light to be measured, and bends the optical path of a part of the light beam of the light to be measured to guide the light to the first spectroscopic measurement unit 1, and Is a reflecting mirror that guides the remaining luminous flux of the luminous flux to the second spectroscopic measurement unit 2. In the example shown in FIG. 1, the branching mirror 5 is a reflecting mirror having a size smaller than the light beam size of the measured light at the position (arrangement position) where the branching mirror 5 is arranged. Such a branching mirror 5 can be arranged in the light beam of the measured light, and reflects a part of the light beam of the measured light beam in a cross-sectional area (area on a plane with the optical axis as a normal). The light can be guided to the first spectroscopic measurement unit 1 and the luminous flux of the remaining portion of the cross-sectional area can be guided to the second spectroscopic measurement unit 2 as it is. In the example shown in FIG. 1, the luminous flux of a part of the cross-sectional area is a luminous flux that diffuses from the measurement area SP at an angle α2, and the luminous flux of the remaining part of the cross-sectional area diffuses at an angle α1 from the measurement area SP. It is a light beam obtained by removing the light beam at the angle α2 from the incoming light beam (α1> α2).

  Note that the branch mirror 5 may be, for example, a reflecting mirror (a donut-shaped mirror) having a through hole. Such a split mirror 5 is arranged such that the through-hole is located within the light beam of the measured light, so that the light beam that has passed through the through-hole among the light beams of the measured light is subjected to the second spectral analysis. The light can be guided to the measurement unit 2, and the remaining light beam of the light beam to be measured can be reflected by a mirror portion other than the through-hole in the branch mirror 5 and bent to be guided to the first spectral measurement unit 1. .

  Further, for example, the branch mirror 5 may be a so-called half mirror (semi-transparent mirror).

  Here, since the half mirror generally has a relatively large polarization dependency, it is preferable that the branch mirror 5 is a reflector having the above-mentioned relatively small size or a reflector having a through hole. In particular, from the viewpoint of low polarization dependence, the branch mirror 5 is preferably a metal reflection mirror having a reflection film formed of a metal material such as aluminum or silver (including their alloys). For example, a half mirror having a reflection film formed of chromium (Cr) has a polarization dependence of about 1.5 times, whereas a reflection mirror having a reflection film formed of aluminum (Al) has a polarization dependence of about 1.5 times. It is 1.05 times. The polarization dependence is a ratio between the reflectance of P-polarized light and the reflectance of S-polarized light.

  When the branch mirror 5 is a reflective mirror having the above-described relatively small size or a reflective mirror having a through hole, the branch mirror 5 has an angle of less than 45 degrees with respect to a reference plane whose normal is the optical axis AX. Preferably, they are arranged at an angle. Usually, the polarization dependence of a mirror depends on the angle of incidence, and the smaller the angle of incidence, the smaller the polarization dependence. In particular, when the angle is 45 degrees or more, the polarization dependence increases. FIG. 2 shows, as a typical example, the polarization dependence of the incident angle in the case of an aluminum mirror. Therefore, by arranging the split mirror 5 at an angle of less than 45 degrees with respect to the reference plane, the incident angle of the light to be measured with respect to the split mirror 5 becomes less than 45 degrees. Therefore, such an optical characteristic measuring device D can further reduce the polarization dependence.

  The measurement angle variable optical system 3 receives the light to be measured, which has formed the first image IM1 by the light receiving optical system 6 at the predetermined position P1, and the measurement target image (second image) IM2 at the predetermined position P2. Is a relay optical system that reconverges and makes the second measurement angle of the second spectrometer 2 variable in the present embodiment. Such a measurement angle variable optical system 3 includes, for example, a plurality of lens groups, and moves one or more of the plurality of lens groups along the optical axis AX direction to thereby provide a focal length (relay magnification). Is a variable magnification optical system (relay variable magnification optical system). Such a measurement angle variable optical system 3 can change the angle of view by changing the focal length, and can change the second measurement angle.

  In one example, the measurement angle variable optical system 3 includes, in order from the object side to the image side, a first negative lens group 31 having a negative refractive power as a whole and a second positive lens group having a positive refractive power as a whole. 32. The first lens group 31 includes one or a plurality of optical lenses, and mainly functions as a variator (magnification system). The second lens group 32 includes one or a plurality of optical lenses, and mainly functions as a compensator (correction system). In the present embodiment, the first and second lens groups 31 and 32 move along the optical axis at the time of zooming, whereby the measurement angle variable optical system 3 changes the focal length.

  As described above, in the present embodiment, the measurement angle variable optical system 3 is relatively easily realized by the relay variable power optical system that varies the focal length.

  The first and second spectrometers 1 and 2 are devices that are connected to the control processor 4 and spectrally measure the light to be measured under the control of the control processor 4. The partial light beam (light beam at an angle α2) of the total light beam of the measured light, which is reflected by the splitting mirror 5 and whose optical path is bent, is guided to the first spectroscopic measurement unit 1, and is transmitted to the first spectroscopic measurement unit. 1 spectroscopically measures the light flux of the part with the first accuracy, and outputs the measurement result (first measurement result) to the control processing unit 4. The remaining light flux (light flux obtained by removing the light flux at the angle α2 from the light flux at the angle α1) of the total light flux of the light to be measured, which is reflected by the splitting mirror 5 and whose optical path has not been bent, is a second spectral measurement unit. 2, the second spectroscopic measurement unit 1 spectroscopically measures the remaining light flux with the second accuracy, and outputs the measurement result (second measurement result) to the control processing unit 4. The first and second spectrometers 1 and 2 have different accuracies. In the present embodiment, the first accuracy of the first spectrometer 1 is higher than the second accuracy of the second spectrometer 2. That is, the first spectrometer 1 has higher accuracy than the second spectrometer 2.

  More specifically, the first spectrometer 1 is a device that performs spot measurement (spot measurement, one-point measurement) that measures the light to be measured as one point and outputs one first measurement result. The light to be measured emitted from a relatively narrow measurement area SP (for example, the first measurement angle is in a range of about 0.1 ° to about 3 °) is measured. That is, the first spectroscopic measurement unit 1 performs measurement by treating the measured light as one regardless of the radiation position of the measured light. Such a first spectroscopic measurement unit 1 is a spectrophotometer that spectroscopically measures light to be measured at predetermined wavelength intervals using a spectroscopic optical element such as a diffraction grating. The first spectral measuring unit 1 of the spectral type includes, for example, a lens system 12, a reflective diffraction grating 13, a line sensor 14, and a housing for accommodating the lens system 12, the reflective diffraction grating 13, and the line sensor 14. 10 is provided. The housing 10 is a box formed of a material having a light-shielding property with respect to a wavelength range in which the line sensor 14 can receive light. On one side surface, the measured light reflected by the branch mirror 5 and having an optical path bent is formed. An entrance opening 11 having, for example, a slit shape for guiding the part of the light into the housing 10 is formed. The first spectroscopic measurement unit 1 is configured to provide a position P3 (a position corresponding to the position P1) where the entrance aperture 11 forms an image (first image) IM1 of the measurement target by the light receiving optical system 6 and converges the measured light. ). The light to be measured entering from the entrance aperture 11 enters the lens system 12, is collimated (collimated) by the lens system 12, enters the reflection type diffraction grating 13, and is diffracted by the reflection type diffraction grating 13. Is reflected. The reflected light again enters the lens system 12, and is formed as a wavelength dispersion image of the optical image on the light receiving surface of the line sensor 14 by the lens system 12. The line sensor 14 includes a plurality of photoelectric conversion elements arranged along one direction. The photoelectric conversion element is, for example, a silicon photodiode (SPD) or the like. The line sensor 14 generates an electric signal representing an intensity level for each wavelength by photoelectrically converting the wavelength dispersion image of the light image formed on the light receiving surface by each of the plurality of photoelectric conversion elements. Then, the line sensor 14 outputs the electric signal (first measurement result) to the control processing unit 4.

  The second spectroscopic measurement unit 2 is a device that performs two-dimensional measurement in which the measured light is measured two-dimensionally as a surface and outputs a second measurement result of a two-dimensional distribution, and has a relatively wide measurement area SP (for example, The light to be measured emitted from the second measurement angle in the range of about 10 ° to about 30 °) is measured. That is, the second spectrometer 2 measures the measured light at each radiation position of the measured light to measure the distribution of the optical characteristics. Such a second spectroscopic measurement unit 2 is a tristimulus value photometer that measures the light to be measured within a predetermined wavelength range by using, for example, an optical filter or the like. Such a tristimulus value type second spectroscopic measurement unit 2 is, for example, the rotation type second spectroscopic measurement unit 2a in the first mode shown in FIGS. 1 and 3A. The second spectrometer 2a of the first embodiment includes a filter selector 21 and a two-dimensional sensor (area sensor) 22. The filter selecting unit 21 is a device that selects one optical filter 211 used for filtering the light to be measured from among the plurality of optical filters 211. The filter selection unit 21 includes a plurality of optical filters 211, a filter holding member 212 that holds the plurality of optical filters 211, and a motor 213 that generates a driving force for moving the filter holding members 212. In the example shown in FIGS. 1 and 3A, the plurality of optical filters 211 include three first to third optical filters 211-R, 211-G, and 211-B having different spectral responsivities. Each of the first to third optical filters 211-R, 211-G, 211-B has, for example, a spectral responsivity close to a CIE (International Commission on Illumination) color matching function, as shown in FIG. 4A. That is, the first optical filter 211-R has a spectral response approximating the CIE color matching function z (λ), and the second optical filter 211-G has a spectral response approximating the CIE color matching function y (λ). The third optical filter 211-B has a spectral responsivity close to the CIE color matching function x (λ). Alternatively, each of the first to third optical filters 211-R, 211-G, and 211-B may have, for example, the spectral responsivity shown in FIGS. 4B and 4C. The filter holding member 212 is, for example, a disk having four first to fourth through openings formed at equal intervals in the circumferential direction. These first to fourth through openings are formed in sizes corresponding to the first to third optical filters 211-R, 211-G, 211-B. The first to third optical filters 211-R, 211-G, 211-B are fitted and fixed by, for example, an adhesive. In the present embodiment, the optical filter is not fitted in the fourth through opening. Alternatively, an ND filter may be fitted and fixed in the fourth through opening. The rotation shaft 214 is inserted through the center of the filter holding member 212, and teeth are formed on the peripheral surface thereof to form a gear. The output shaft of the motor 213 is provided with a gear. The gear of the motor 213 meshes with the gear of the filter holding member 212, and the driving force of the motor 213 is transmitted to the filter holding member 212. Thus, the filter holding member 212 is driven to rotate about the rotation shaft 214. Then, the filter holding member 212 is aligned with the optical axis of the second spectrometer 2 each time the optical axes of the first to third optical filters 211-R, 211-G, 211-B are sequentially rotated. , Between the variable measurement angle optical system 3 and the two-dimensional sensor. The two-dimensional sensor 22 includes a plurality of photoelectric conversion elements (one example of a pixel) arranged in a two-dimensional array in two linearly independent directions (for example, two directions orthogonal to each other). The photoelectric conversion element is, for example, a silicon photodiode (SPD) or the like. The two-dimensional sensor 22 is arranged such that its light receiving surface is located at the position P2 where the measurement angle variable optical system 3 forms an image (second image) IM2 of the measurement target and re-converges the measured light. Is done. In such a second spectroscopic measurement unit 2, the remaining portion of the measured light that has proceeded without bending the optical path by the splitting mirror 5 is removed from the first to third optical filters 211-R, 211-G, and 211. The image (second image) IM2 of the measurement target is formed on the light receiving surface of the two-dimensional sensor 22 by the measurement angle variable optical system 3 via any one of -B and reconverge. The two-dimensional sensor 22 photoelectrically converts the second image IM2 formed on the light receiving surface with each of the plurality of photoelectric conversion elements, thereby generating an electric signal indicating an intensity level of each photoelectric conversion element (pixel). Generate Then, the two-dimensional sensor 22 outputs the electric signal (second measurement result) to the control processing unit 4. Here, any one of the first to third optical filters 211-R, 211-G, 211-B is sequentially selected so as to be located on the optical axis of the second spectroscopic measurement unit 2. Thus, the second measurement result corresponding to the optical filter 211 is output from the two-dimensional sensor 22 to the control processing unit 4. That is, in the above example, since the first optical filter 211-R of the CIE color matching function z (λ) is located on the optical axis of the second spectroscopic measurement unit 2, the second measurement result regarding the Z stimulus value is 2 The second optical filter 211-G of the CIE color matching function y (λ) is output from the dimensional sensor 22 to the control processing unit 4 and located on the optical axis of the second spectroscopic measurement unit 2, so that the Y stimulus value is obtained. 2 The measurement result is output from the two-dimensional sensor 22 to the control processing unit 4, and the third optical filter 211-B of the CIE color matching function x (λ) is located on the optical axis of the second spectral measurement unit 2. Then, the second measurement result regarding the X stimulus value is output from the two-dimensional sensor 22 to the control processing unit 4.

  The second spectrometer 2 is not limited to the spectrometer 2a of the first embodiment, but may be a three-plate prism type second spectrometer 2b of the second embodiment shown in FIG. 3B. Alternatively, the second spectroscopic measurement unit 2c of the sequential branch type in the third mode shown in FIG. 3C may be used.

  The second spectroscopic measurement unit 2b of the second embodiment shown in FIG. 3B includes three first to third prisms 23-R, 23-G, 23-B and three first to third two-dimensional prisms. And sensors 24-R, 24-G and 24-B. Each of the first to third prisms 23-R, 23-G, and 23-B has a substantially triangular prism shape. The first side surface of the second prism 23-G and the first side surface of the first prism 23-R abut on the first and second side surfaces adjacent to each other in the third prism 23-B. One of the first side surface of the third prism 23-B and the first side surface of the second prism 23-G reflects light in the G (green) wavelength range and R (red) and B (blue). A first optical filter film that transmits each light in the wavelength range of (3) is formed, and R (red) is provided on one of the second side surface of the third prism 23-B and the first side surface of the first prism 23-R. A) a second optical filter film that reflects light in the wavelength range of B) and transmits light in the wavelength range of B (blue). A third two-dimensional sensor 24-B is disposed on the third side surface of the third prism 23-B such that the light receiving surface faces the third side surface. Note that a B optical filter 25-B that transmits only the B (blue) wavelength range is interposed between the third side surface of the third prism 23-B and the light receiving surface of the third two-dimensional sensor 24-B. May be. The second side surface of the second prism 23-B is an incident surface of the light to be measured, and the third side surface of the second prism 23-G is arranged such that the light receiving surface faces the third side surface. A second two-dimensional sensor 24-G is provided. A G optical filter 25-G that transmits only the G (green) wavelength range is interposed between the third side surface of the second prism 23-G and the light receiving surface of the second two-dimensional sensor 24-G. May be. The third side surface of the first prism 23-R is an emission surface, and the first side surface of the first prism 23-R is provided with a first light receiving surface facing the third side surface. The two-dimensional sensor 24-R is arranged. Each of the first to third two-dimensional sensors 24-R, 24-G, 24-B includes a plurality of photoelectric conversion elements arranged in a two-dimensional array like the two-dimensional sensor 22. Is done. In the second spectroscopic measurement unit 2b according to the second aspect, the light to be measured enters from the second side surface of the second prism 23-G. Of the incident light to be measured, light in the wavelength range of G (green) is reflected by the first optical filter film, further reflected by the second side surface of the second prism 23-G, and reflected from the third side surface. The light is emitted, received by the second two-dimensional sensor 24-G, and photoelectrically converted. Of the light to be measured, each light having a wavelength range of R (red) and B (blue) transmitted through the first optical filter film is transmitted from the second side surface of the third prism 23-B to the third prism 23-B. Light is incident on B. The light in the wavelength range of B (blue) of the incident light to be measured is reflected by the second optical filter film, is emitted from the third side surface of the third prism 23-B, and is output by the third two-dimensional sensor. The light is received by 24-B and photoelectrically converted. Then, of the light to be measured, light having a wavelength range of R (red) that has passed through the second optical filter film enters the first prism 23-R from the first side surface of the first prism 23-R. . Of the incident light to be measured, light in the R (red) wavelength range is emitted from the third side surface of the first prism 23-R, received by the first two-dimensional sensor 24-R, and subjected to photoelectric conversion. You. Each electric signal (each second measurement result) generated by photoelectric conversion by each of the first to third two-dimensional sensors 24-R, 24-G, 24-B is converted into a first to third two-dimensional sensor. Each of the sensors 24-R, 24-G, 24-B is output to the control processing unit 4.

  The second spectroscopic measurement unit 2c according to the third embodiment shown in FIG. 3C includes two first and second dichroic mirrors 26-G and 26-B and three first to third optical filters 27-R and 27. -G, 27-B, and three first to third two-dimensional sensors 28-R, 28-G, 28-B. The first dichroic mirror 26-G is an optical filter that reflects light in the G (green) wavelength range and transmits each light in the R (red) and B (blue) wavelength ranges. -B is an optical filter that reflects light in the B (blue) wavelength range and transmits light in the R (red) wavelength range. The first optical filter 27-R is an R optical filter that transmits only the R (red) wavelength range, and the second optical filter 27-G is a G optical filter that transmits only the G (green) wavelength range. The third optical filter 27-B is a B optical filter that transmits only the B (blue) wavelength range. Each of the first to third two-dimensional sensors 28-R, 28-G, 28-B includes a plurality of photoelectric conversion elements arranged in a two-dimensional array like the two-dimensional sensor 22. Is done. A first optical filter 27-R is disposed on a light receiving surface of the first two-dimensional sensor 28-R, and a normal line of the light receiving surface is used as an optical axis (first optical axis). Similarly, a second optical filter 27-G is disposed on the light receiving surface of the second two-dimensional sensor 28-G, and the normal line of the light receiving surface is used as its optical axis (second optical axis). A third optical filter 27-B is disposed on the light receiving surface of the three two-dimensional sensor 28-B, and the normal to the light receiving surface is the optical axis (third optical axis). Then, the first two-dimensional sensor 28-R and the first optical filter 27-R, the second two-dimensional sensor 28-G and the second optical filter 27-G, and the third two-dimensional sensor 28-B And the third optical filter 27-B are defined by the second optical axis of the second two-dimensional sensor 28-G and the third two-dimensional sensor 28 with respect to the first optical axis of the first two-dimensional sensor 28-R. -B third optical axes are arranged so as to be orthogonal, and the first optical axis of the first two-dimensional sensor 28-R intersects with the second optical axis of the second two-dimensional sensor 28-G. A first dichroic mirror 26-G is disposed at a position so as to intersect at 45 degrees with a first optical axis of the first two-dimensional sensor 28-R, and a first dichroic mirror 26-G is disposed at the first position. At the position where the optical axis intersects with the third optical axis of the third two-dimensional sensor 28-B, a first two-dimensional A second dichroic mirror 26-B are arranged so as to first optical axis of the capacitors 28-R intersect at 45 degrees. In the second spectroscopic measurement unit 2c according to the third aspect, the measured light enters the first dichroic mirror 26-G. The light in the wavelength range of G (green) of the incident light to be measured is reflected by the first dichroic mirror 26-G and passes through the second optical filter 27-G to the second two-dimensional sensor 28. -G and are photoelectrically converted. Of the light to be measured, each light having a wavelength range of R (red) and B (blue) transmitted through the first dichroic mirror 26-G is incident on the second dichroic mirror 26-B. The light in the wavelength range of B (blue) of the incident light to be measured is reflected by the second dichroic mirror 26-B and passes through the third optical filter 27-B to the third two-dimensional sensor 28. -B and are photoelectrically converted. Then, of the light to be measured, light having a wavelength range of R (red) that has passed through the second dichroic mirror 26-B is passed through the first optical filter 27-R to the first two-dimensional sensor 28. -R is received and photoelectrically converted. Each electric signal (each second measurement result) generated by photoelectric conversion by each of the first to third two-dimensional sensors 28-R, 28-G, 28-B is converted into a first to third two-dimensional sensor. Each of the sensors 28-R, 28-G, and 28-B is output to the control processing unit 4.

  Returning to FIG. 1, the input / output unit 8 is connected to the control processing unit 4, performs a predetermined operation input to the optical property measuring device D, and outputs predetermined information from the optical property measuring device D. is there. The input / output unit 8 includes, for example, an input unit 81, an output unit 82, and an interface unit (IF unit) 83.

  The input unit 81 is connected to the control processing unit 4 and, for example, receives various commands such as a command for instructing measurement of the measured light and various data necessary for measurement such as input of an identifier in the measured light. The input device to the optical property measuring device D is, for example, a plurality of input switches to which predetermined functions are assigned, a keyboard, a mouse, and the like. The output unit 82 is connected to the control processing unit 4, and under the control of the control processing unit 4, the command and data input from the input unit 81 and the measurement result of the measured light measured by the optical property measurement device D ( For example, it is a device that outputs a first measurement result, a second measurement result, and predetermined optical characteristics based on the first and second measurement results), such as a display device such as a CRT display, an LCD and an organic EL display, and a printer. A printing device.

  Note that a touch panel may be configured by the input unit 81 and the output unit 82. In the case of configuring this touch panel, the input unit 81 is a position input device for detecting and inputting an operation position of, for example, a resistive type or a capacitive type, and the output unit 82 is a display device. In this touch panel, a position input device is provided on a display surface of the display device, one or more candidates for input content that can be input to the display device are displayed, and the user touches a display position where the input content desired to be input is displayed. Then, the position is detected by the position input device, and the display content displayed at the detected position is input to the optical characteristic measuring device D as the operation input content of the user. With such a touch panel, the user can easily and intuitively understand the input operation, so that the optical characteristic measuring device D that is easy for the user to handle is provided.

  The IF unit 83 is a circuit that is connected to the control processing unit 4 and that inputs and outputs data to and from an external device under the control of the control processing unit 4. For example, an interface circuit of an RS-232C serial communication system is used. , An interface circuit using the Bluetooth (registered trademark) standard, an interface circuit for performing infrared communication such as the IrDA (Infrared Data Association) standard, and an interface circuit using the USB (Universal Serial Bus) standard.

  The storage unit 9 is a circuit that is connected to the control processing unit 4 and stores various predetermined programs and various predetermined data under the control of the control processing unit 4. The various predetermined programs include, for example, a control processing program such as a measurement program for measuring the measured light. The various types of predetermined data include a correction coefficient obtained by a correction calculation unit 422 described later. Such a storage unit 9 includes, for example, a ROM (Read Only Memory) which is a nonvolatile storage element, an EEPROM (Electrically Erasable Programmable Read Only Memory) which is a rewritable nonvolatile storage element, and the like. The storage unit 9 includes a RAM (Random Access Memory) serving as a working memory of the so-called control processing unit 4 for storing data and the like generated during execution of the predetermined program.

  The control processing unit 4 is a circuit for controlling each unit of the optical characteristic measuring device D according to the function of each unit, and obtaining the optical characteristics of the measured light. The control processing unit 4 includes, for example, a CPU (Central Processing Unit) and its peripheral circuits. By executing the control processing program, the control processing unit 4 functionally includes a control unit 41 and an optical characteristic calculation unit 42.

  The control section 41 is for controlling each section of the optical property measuring device D according to the function of each section.

  The optical characteristic calculation unit 42 determines a predetermined optical characteristic (the color of the measured light in the present embodiment) of the measured light based on the first and second measurement results of the first and second spectroscopic measuring units 1 and 2, respectively. Is what you want. In the present embodiment, the first spectrometer 1 has the first accuracy higher than the second accuracy of the second spectrometer 2, as described above. As in Patent Document 1, the second result of the second spectrometer 1 is corrected by the first result of the first spectrometer 1, and the optical characteristic of the measured light is obtained. For this reason, the optical property calculating section 42 corrects the second result of the second spectroscopic measuring section 2 with the first result of the first spectroscopic measuring section 1 to obtain the optical property of the measured light. The optical property calculation unit 42 functionally includes a property calculation unit 421 and a correction calculation unit 422.

Here, it is assumed that the spectral distribution (first measurement result) of the measured light measured by the first spectral measurement unit 1 is P (λ), and the CIE color matching functions are x (λ), y (λ), z ( λ), the tristimulus values of the measured light are given by the following equations (1), (2), and (3). The CIE color matching functions x (λ), y (λ), z (λ) are stored in the storage unit 9 in advance.
X = ∫P (λ) · x (λ) dλ (1)
Y = ∫P (λ) · y (λ) dλ (2)
Z = ∫P (λ) · z (λ) dλ (3)

On the other hand, each pixel value (second measurement result) of each pixel (n, m) of the measured light measured by the second spectroscopic measurement unit 2 is represented by Xc (n, m), Yc (n, m), Xc (n). , M), and the pixel on the second spectroscopic measurement unit 2 corresponding to the point of the light to be measured (the measurement point of the spot measurement) measured by the first spectroscopic measurement unit 1 is (n ₀ , m ₀ ). The following equations (4), (5) and (6) hold. Note that (n ₀ , m ₀ ) is checked in advance and stored in the storage unit 9.
_{X = f {Xc (n 0} , m 0), Yc (n 0, m 0), Zc (n 0, m 0)} ··· (4)
_{Y = g {Xc (n 0} , m 0), Yc (n 0, m 0), Zc (n 0, m 0)} ··· (5)
_{Z = h {Xc (n 0} , m 0), Yc (n 0, m 0), Zc (n 0, m 0)} ··· (6)

  Each coefficient of the functions f, g, and h in the equations (4) to (6) is a correction coefficient, and the relational expressions of the equations (4) to (6) are calculated as follows in the same manner as in Patent Document 1. When the equation (7) is set, the correction coefficients CP1, CP2, and CP3 are obtained as in the equations (8), (9), and (10).

CP1 = X / Xc (n ₀ , m ₀ ) (8)
CP2 = Y / Yc (n ₀ , m ₀ ) (9)
CP3 = Z / Zc (n ₀ , m ₀ ) (10)

The corrected tristimulus values of each pixel of the second spectroscopic measurement unit 2 are given by the following equations (11), (12), and (13).
X (n, m) = CP1 · Xc (n, m) (11)
Y (n, m) = CP2 · Xc (n, m) (12)
Z (n, m) = CP3 · Xc (n, m) (13)

  Therefore, the correction operation unit 422 obtains the correction coefficients CP1, CP2, and CP3 based on the first and second measurement results of the first and second spectroscopic measurement units, respectively, as described above. CP2 and CP3 are stored in the storage unit 9. Then, the characteristic calculation unit 421 calculates the correction coefficients CP1, CP2, and CP3 based on the second measurement result of the second spectrum measurement unit 2 and the first and second measurement results of the first and second spectrum measurement units 1 and 2, respectively. Based on the above, the tristimulus values of the measured light are obtained as predetermined optical characteristics by using the above equations (11) to (13). As described above, in the present embodiment, even if the second accuracy of the second spectroscopic measurement unit 2 is relatively low, the second measurement result of the second spectroscopic measurement unit 2 is converted to the first measurement having the relatively high first accuracy. Since the correction is performed using the first measurement result of the spectrometer 1, the optical property measuring apparatus D according to the present embodiment can improve the second measurement result of the second spectrometer 2 with the second accuracy.

  In such an optical characteristic measuring device D, when the measurement is started, the light to be measured is received by the light receiving optical system 6 and is incident on the aperture stop 7. A part of the light to be measured that has passed through the aperture stop 7 is reflected by the splitting mirror 5, its optical path is bent, and the light is guided to the first spectrometer 1, and the remaining part is directly measured by the measurement angle variable optical system 3. The light is guided to the second spectroscopic measurement unit 2 via. The part of the light to be measured guided to the first spectroscopic measurement unit 1 is separated and measured, and the first measurement result is output from the first spectroscopic measurement unit 1 to the control processing unit 4. Here, since the split mirror 5 has a small polarization dependency, the first spectroscopic measurement unit 1 can perform measurement with higher accuracy even when the object to be measured has polarization characteristics. The remaining light to be measured guided to the second spectroscopic measurement unit 2 is separated and measured, and the second measurement result is output from the second spectroscopic measurement unit 2 to the control processing unit 4. Here, since the remaining light to be measured guided to the second spectroscopic measurement unit 2 passes through the measurement angle variable optical system 3, the second spectroscopic measurement unit 2 sets the second measurement angle γ as described later. Can be changed to The optical characteristic calculation unit 42 of the control processing unit 4 calculates the correction coefficients CP1, CP2, and CP3 based on the first and second measurement results by the correction calculation unit 422, and calculates the calculated correction coefficients CP1, CP2, and CP3 and the second correction coefficient. Based on the measurement result, a two-dimensional distribution of the optical characteristics of the measured light is obtained by the characteristic calculation unit and output to the output unit 82. In addition, if necessary, the optical property calculation unit 42 outputs the obtained predetermined optical property to an external device (not shown) via the IF unit 83. Note that the correction coefficients CP1, CP2, and CP3 may be obtained for each measurement, may be obtained for each predetermined number of measurements, or may be obtained for each predetermined period. In the case where it is obtained every predetermined number of measurements or every predetermined period, the obtained correction coefficients CP1, CP2, and CP3 are stored in the storage unit 9 for the next use.

  Next, the operation of changing the ratio between the first measurement angle of the first spectrometer 1 and the second measurement angle of the second spectrometer 2 will be described below. FIG. 5 is a diagram for explaining the operation of the measurement angle variable optical system in the optical characteristic measuring device of the present embodiment. FIG. 5A shows a case where the second measurement angle is 10 °, and FIG. 5B shows a case where the second measurement angle is 28 °. FIG. 6 is a diagram for describing luminance distribution measurement by the optical characteristic measuring device according to the present embodiment. FIG. 6A shows a state of measurement when measuring the luminance distribution of the liquid crystal display, and FIG. 6B shows a state of measurement when measuring the luminance distribution of the display character in the instrument panel of the car.

  In the optical characteristic measuring device D according to the present embodiment, the first measurement angle β of the first spectroscopic measurement unit 1 is fixed at a predetermined angle β1 (for example, 0.1 °, 0.2 °, 1 °, or the like). (Β = β1). Then, the second measurement angle γ of the second spectroscopic measurement unit 2 is changed by the measurement angle variable optical system 3 in a predetermined angle range γ1 to γ2 (γ1 ≦ γ ≦ γ2).

  For example, when the size of the two-dimensional sensor 22 in the second spectroscopic measurement unit 2 is 5 mm and the focal length f6 of the light receiving optical system 6 is 57 mm, in order to set the second measurement angle γ to 10 °, FIG. As shown in the figure, the size of the first image IM1 is set to 10 mm, and the measurement angle variable optical system 3 sets the first focal length f3 to 22 mm and the magnification δ to -0.5, respectively. And the positions of the second lens groups 31 and 32 are adjusted. As a result, the first image IM1 having a size of 10 mm becomes a second image IM2 having a size of 5 mm (= 10 × 0.5) by the measurement angle variable optical system 3, and is formed on the light receiving surface of the two-dimensional sensor 22. And an image can be measured at the second measurement angle of 10 °.

  On the other hand, in order to set the second measurement angle γ to 28 °, as shown in FIG. 5B, the size of the first image IM1 is set to 30 mm, and the measurement angle variable optical system 3 sets the focal length f3 to 12 mm. Then, the positions of the first and second lens groups 31 and 32 are adjusted so that the magnification δ is set to −0.17. As a result, the first image IM1 having a size of 30 mm becomes a second image IM2 having a size of 5 mm (= 30 × 0.17) by the measurement angle variable optical system 3, and is formed on the light receiving surface of the two-dimensional sensor 22. And an image can be measured at the second measurement angle of 28 °.

  Note that, while changing from the second measurement angle 10 ° to the second measurement angle 28 °, as shown in FIG. 5, the first lens group 31 functioning as a variator moves along a locus that draws a convex curve on the image side. The second lens group 32 functioning as a compensator moves along a locus that draws a monotonous straight line from the object side to the image side.

  Since the second measurement angle γ of the second spectrometer 2 can be changed in this manner, the ratio between the first measurement angle β of the first spectrometer 1 and the second measurement angle γ of the second spectrometer 2, for example, The ratio γ / β of the second measurement angle γ of the second spectrometer 2 to the first measurement angle β of the first spectrometer 1 can be varied in the range of γ1 / β1 to γ2 / β1. In the example shown in FIG. 5, when β1 = 1 °, the ratio γ / β can be varied in the range of 10 to 28.

  As described above, the optical characteristic measuring device D according to the present embodiment can change the ratio γ / β. For example, as shown in FIG. 6A, in measuring the luminance distribution of the liquid crystal display, the optical characteristic measuring device D according to the present embodiment is used. Can measure the spot at the center of the screen of the liquid crystal display at a measurement angle of 1 ° by the first spectroscopic measurement unit 1 and perform the two-dimensional measurement of the entire screen of the liquid crystal display at the measurement angle of 10 ° by the second spectroscopic measurement unit 2. On the other hand, as shown in FIG. 6B, in the measurement of the luminance distribution of the display character in the instrument panel of the car, the optical characteristic measuring device D according to the present embodiment uses the first spectral measurement unit 1 to measure the center of the display character at a measurement angle of 1 °. Spot measurement is performed, and the entire instrument panel can be two-dimensionally measured by the second spectroscopic measurement unit 2 at a measurement angle of 20 °. As described above, the optical characteristic measuring apparatus D according to the present embodiment can realize the measurement of the luminance distribution of the liquid crystal display and the measurement of the luminance distribution of the display character on the instrument panel of the automobile by changing the ratio γ / β with one unit.

  As described above, the optical characteristic measuring device D and the optical characteristic measuring method mounted on the optical characteristic measuring device D according to the present embodiment include the variable measurement angle optical system 3, so that the measurement angle of the second spectrometer 2 can be changed. Therefore, the optical characteristic measuring device D and the optical characteristic measuring method mounted on the optical characteristic measuring device D according to the present embodiment determine the ratio between the first measurement angle of the first spectrometer 1 and the second measurement angle of the second spectrometer 2. Can be changed.

  Then, in the optical property measuring device D and the optical property measuring method mounted thereon in the present embodiment, the first spectroscopic measuring unit 1 can execute the spot measurement, and the second spectroscopic measuring unit 2 executes the two-dimensional measurement. Therefore, the optical property measuring apparatus D and the optical property measuring method mounted thereon according to the present embodiment can change the ratio between the first measurement angle for spot measurement and the second measurement angle for two-dimensional measurement.

  Further, the optical characteristic measuring device D and the optical characteristic measuring method mounted on the optical characteristic measuring device D in the present embodiment can provide the received light amount unchanged even when the light receiving optical system 6 is focused by providing the aperture stop 7.

  In the above-described embodiment, the first area measured at the first measurement angle β of the first spectroscopic measurement unit is changed to the two-dimensional sensor of the second spectroscopic measurement unit 2 according to the magnification of the measurement angle variable optical system 3. When the size (area) of the projected first region changes when projected onto the two-dimensional sensor 22, the size of the first region projected onto the two-dimensional sensor 22 of the second spectroscopic measurement unit 2 is changed. Accordingly, the pixels of the two-dimensional sensor 22 for obtaining the correction coefficients CP1, CP2, and CP3 described above may be selected.

  FIG. 7 is a diagram showing a configuration of a modification of the optical characteristic measuring device. FIG. 8 is a diagram for explaining the relationship between the first region measured at the first measurement angle of the first spectrometer and the two-dimensional sensor of the second spectrometer. 8B shows a standard, FIG. 8A shows a wide angle side (wide side) based on the standard shown in FIG. 8B, and FIG. 8C shows a telephoto side (tele side) based on the standard shown in FIG. 8B. Show.

  Such a spectral characteristic measuring device Da is similar to the above-described spectral characteristic measuring device D. For example, as shown in FIG. 7, a first spectral measuring unit 1, a second spectral measuring unit 2, a variable measurement angle optical system, The system includes a system 3a, a control processing unit 4a, a branch mirror 5, a light receiving optical system 6, an aperture stop 7, an input / output unit 8, and a storage unit 9a. The first spectral measurement unit 1, the second spectral measurement unit 2, the branch mirror, the light receiving optical system 6, the aperture stop 7, and the input / output unit 8 in the spectral characteristic measurement unit Da of these modified embodiments are respectively the spectral characteristic measurement unit described above. D is the same as the first spectrometer 1, the second spectrometer 2, the splitting mirror, the light receiving optical system 6, the aperture stop 7, and the input / output unit 8, and the description thereof is omitted.

  The variable measurement angle optical system 3a is similar to the variable measurement angle optical system 3 described above, and includes a drive unit 33 in addition to the first and second lens groups 31 and 32 described above. The drive unit 33 is connected to the control processing unit 4a, and operates under the control of the control unit 41a of the control processing unit 4a according to the second measurement angle γ of the second spectral measurement unit 2 input from the input unit 81 as described above. This is a mechanism for moving the first and second lens groups 31 and 32 along an optical axis along a suitable locus. In this modification, the first and second lens groups 31 and 32 are moved by the drive unit 33. However, the first and second lens groups 31 and 32 may be manually moved with a so-called zoom ring or the like.

  The control processing unit 4a is similar to the above-described control processing unit 4, and functionally includes an area processing unit 43 in addition to the control unit 41a and the optical property calculation unit 42a.

  The area processing unit 43 corresponds to a first area measured at the first measurement angle β of the first spectroscopic measurement unit 1 from a plurality of pixels (a plurality of photoelectric conversion elements in the present embodiment) in the two-dimensional sensor 22. One or a plurality of pixels to be obtained are obtained.

  As described above, the variable measurement angle optical system 3 is a variable power relay optical system, and the first spectroscopic measurement unit 1 splits the light by the split mirror 5 before entering the variable measurement angle optical system 3. The second spectrometer 2 receives the remaining part of the light to be measured branched by the branching mirror 5 via the variable measurement angle optical system 3 while receiving the light to be measured. Therefore, the size (area) of the first region SP1 measured at the first measurement angle β of the first spectroscopic measurement unit 1 is temporarily projected on the light receiving surface of the two-dimensional sensor 22 of the second spectroscopic measurement unit 2. Then, as shown in FIG. 8, the measurement angle varies according to the magnification of the variable optical system 3. More specifically, when the measurement angle variable optical system 3 is on the wide angle side from the standard, as shown in FIG. 8A, the first light projected on the light receiving surface of the two-dimensional sensor 22 of the second spectroscopic measurement unit 2 is displayed. The area SP1 is smaller than the first area SP1 shown in FIG. 8B, and when the variable measurement angle optical system 3 is on the telephoto side of the standard, as shown in FIG. The first area SP1 projected on the light receiving surface of the dimensional sensor 22 is larger than the first area SP1 shown in FIG. 8B. The area processing unit 43 is configured to measure a first measurement angle β of the first spectral measurement unit 1 from a plurality of pixels (a plurality of photoelectric conversion elements in the present embodiment) of the two-dimensional sensor 22. One or a plurality of pixels corresponding to the area SP1 are obtained. More specifically, the correspondence relationship between the magnification of the measurement angle variable optical system 3, that is, the second measurement angle γ of the second spectroscopic measurement unit 2 and the one or more images corresponding to the first region SP1 is determined. For example, the area processing unit 43 is stored in the storage unit 9a in a table format in advance, and the area processing unit 43 refers to the correspondence based on the second measurement angle γ of the second spectral measurement unit 2 input from the input unit 81, The one or more images corresponding to the first area SP1 are obtained. As described above, when the first and second lens groups 31 and 32 in the measurement angle variable optical system 3a are manually moved using a zoom ring or the like, the first and second lens groups 31 and 32 are used. A position sensor that detects a position along the optical axis direction in at least one of the first and second regions, and the storage unit 9a corresponds to the second measurement angle γ of the second spectroscopic measurement unit 2 and the first region SP1. Instead of the correspondence with the one or a plurality of images, the position along at least one of the first and second lens groups 31 and 32 along the optical axis direction and the one corresponding to the first region SP1 Alternatively, the correspondence relationship with a plurality of images is stored.

  The control unit 41a is similar to the above-described control unit 41, and drives the first and second lens groups 31, 32 in the measurement angle variable optical system 3a to move along the optical axis direction as described above. It controls the unit 33.

  The optical property calculation unit 42a is similar to the above-described optical property calculation unit 42, and based on the pixel values of the one or more pixels obtained by the area processing unit 43, the second measurement result of the second spectral measurement unit 2 Are determined by the first measurement result of the first spectroscopic measurement unit 1 to obtain correction coefficients CP1, CP2, and CP3, and the second measurement of the second spectroscopic measurement unit 2 is performed using the obtained correction coefficients CP1, CP2, and CP3. The result is corrected by the first measurement result of the first spectroscopic measurement unit 1 to obtain a predetermined optical characteristic of the measured light. Therefore, the optical characteristic calculation unit 42a includes the same characteristic calculation unit 421 as described above. , A correction operation unit 422a. The correction operation unit 422a is similar to the correction operation unit 422, and as described above, the correction coefficients CP1, CP2, and CP3 based on the first and second measurement results of the first and second spectral measurement units 1 and 2, respectively. At this time, the pixel values of the one or more pixels obtained by the area processing unit 43 are used.

  The storage unit 9a is similar to the storage unit 9 described above, and further stores the correspondence.

  According to such a modification, one or a plurality of pixels corresponding to the first area SP1 measured at the first measurement angle β of the first spectroscopic measurement unit 1 are selected from the plurality of pixels in the two-dimensional sensor 22. The correction coefficients CP1, CP2, and CP3 are obtained based on the obtained pixel values of the obtained pixels, and the second measurement result of the second spectroscopic measurement unit 2 is calculated using the obtained correction coefficients CP1, CP2, and CP3. Since the correction is performed based on the first measurement result of the first spectrometer 1, the correction can be performed more appropriately.

  In the above-described embodiment, in order to change the measurement angle of the second spectrometer 2, the optical property measuring device D includes the variable measurement angle optical system 3 on the incident side of the second spectrometer 2. However, instead of the incident side of the second spectroscopic measurement unit 2, the optical characteristic measuring device D may include a measurement angle variable optical system 3 on the incident side of the first spectroscopic measurement unit 1, or In addition to the incident side of the second spectrometer 2, the optical property measuring apparatus D is provided with a variable measurement angle optical system 3 on each of the incident sides of the first and second spectrometers 1, 2. Is also good.

  Further, in the above-described embodiment, the first spectroscopic measurement unit 1 is of a spectral type, but by using an optical filter having a higher spectral response than the optical filter 211 of the second spectroscopic measurement unit 2, It may be a stimulus value type.

  Further, in the above-described embodiment, since the optical property measuring device D is a colorimeter, the second spectral measuring unit 2 includes three optical filters 211-R, 211-G, and 211-G having different spectral responsivities. B, the light to be measured is measured with three types of spectral sensitivities. However, when the optical characteristic measuring device D is a luminance meter, the second spectral measuring unit 2 uses the single type of spectral sensitivity to measure the light to be measured. Should be measured.

  Further, in the above-described embodiment, the second spectroscopic measurement unit 2 may be configured to include a color area sensor configured with, for example, a Bayer array or the like.

  The present specification discloses various aspects of the technology as described above, and the main technology is summarized below.

  An optical characteristic measuring device according to an aspect includes first and second spectrometers for spectroscopically measuring light to be measured with first and second accuracy different from each other, and a first measurement angle and a first measurement angle of the first spectrometer. A measurement angle variable optical system that changes at least one of a second measurement angle of a second spectrometer, and the measured light based on first and second measurement results of the first and second spectrometers, respectively. And an optical characteristic calculation unit for obtaining the predetermined optical characteristic.

  Since such an optical characteristic measuring apparatus includes a measurement angle variable optical system, the measurement angle can be changed. Therefore, the optical characteristic measuring device can change the ratio between the first measurement angle of the first spectrometer and the second measurement angle of the second spectrometer.

  In another aspect, in the above-described optical characteristic measuring device, the measurement angle variable optical system is a relay optical system that varies a focal length.

  In such an optical characteristic measuring apparatus, a measurement angle variable optical system can be realized relatively easily by a relay optical system (relay variable magnification optical system) that changes the focal length.

  In another aspect, in the above-described optical characteristic measuring device, the first spectral measurement unit has the first accuracy higher than the second accuracy of the second spectral measurement unit, and the optical characteristic calculation unit includes: The second measurement result of the second spectrometer is corrected with the first measurement result of the first spectrometer to obtain a predetermined optical characteristic of the measured light.

  Such an optical characteristic measuring apparatus is capable of converting the second measurement result of the second spectroscopic measurement unit into the first spectrometer having a relatively high first accuracy even if the second accuracy of the second spectroscopic measurement unit is relatively low. Since the correction is performed using the first measurement result of the measurement unit, the second measurement result of the second spectroscopic measurement unit can be improved from the second accuracy.

  In another aspect, in the above-described optical characteristic measuring apparatus, the second spectroscopic measurement unit measures the light to be measured in two dimensions as a plane, and includes a plurality of pixels arranged in a two-dimensional array. A two-dimensional sensor that receives the measured light at the plurality of pixels and has a first one that is measured at a first measurement angle of the first spectrometer from among the plurality of pixels of the two-dimensional sensor. The image processing apparatus further includes an area processing unit that obtains one or a plurality of pixels corresponding to an area, wherein the optical characteristic calculation unit performs the second spectral analysis based on the pixel values of the one or the plurality of pixels obtained by the area processing unit. A correction coefficient for correcting the second measurement result of the measurement unit with the first measurement result of the first spectroscopic measurement unit is obtained.

  Such an optical characteristic measuring device obtains one or a plurality of pixels corresponding to a first region measured at a first measurement angle of a first spectroscopic measurement unit from a plurality of pixels of a two-dimensional sensor. A correction coefficient is obtained based on the pixel value of the obtained pixel, and the second measurement result of the second spectral measurement unit is corrected with the first measurement result of the first spectral measurement unit using the obtained correction coefficient. Can be corrected more appropriately.

  In another aspect, in the above-described optical characteristic measuring apparatus, the first spectroscopic measurement unit performs the spot measurement of measuring the light to be measured as one point and outputting one measurement result, and The spectrometer performs two-dimensional measurement in which the measured light is measured two-dimensionally as a surface and a measurement result of a two-dimensional distribution is output.

  Such an optical characteristic measuring device can change the ratio between the first measurement angle of spot measurement (spot measurement) and the second measurement angle of two-dimensional measurement.

  The optical characteristic measuring method according to another aspect includes a first and second spectroscopic measuring steps of spectroscopically measuring the light to be measured with first and second precisions different from each other, and the first and second spectroscopic measuring steps. An optical characteristic calculating step of obtaining predetermined optical characteristics of the measured light based on the first and second measurement results of each of the steps. At least one of the first and second spectral measurement steps includes a measurement angle The measured light is split through a measurement angle variable optical system that varies the wavelength.

  In such an optical characteristic measuring method, at least one of the first and second spectroscopic measurement steps disperses the measured light through a measurement angle variable optical system. For this reason, the optical characteristic measuring method can change the ratio between the first measurement angle in the first spectral measurement step and the second measurement angle in the second spectral measurement step.

  This application is based on Japanese Patent Application No. 2014-111350 filed on May 29, 2014, the contents of which are included in the present application.

  Although the present invention has been described above appropriately and sufficiently through the embodiments with reference to the drawings in order to express the present invention, it is easy for those skilled in the art to modify and / or improve the above-described embodiments. It should be recognized that it is possible. Therefore, unless a modification or improvement performed by those skilled in the art is at a level that departs from the scope of the claims set forth in the claims, the modification or the improvement will not be included in the scope of the claims. Is interpreted as being included in

According to the present invention, an optical characteristic measuring device and an optical characteristic measuring method can be provided.

Claims (7)

A light receiving optical system for condensing light to be measured from the object to be measured,
First and second spectrometers for spectroscopically measuring the measured light having passed through the light receiving optical system with first and second precisions different from each other;
A measurement angle variable optical system including a relay optical system that varies a focal length of the second spectrometer while refocusing the first image formed by the light receiving optical system on a second image ;
An optical property calculation unit for obtaining a predetermined optical property of the measured light based on the first and second measurement results of the first and second spectrometers, respectively;
The second spectrometer is configured to measure the two-dimensionally measured light as a surface,
The ratio between the measurement angle of the first spectrometer and the measurement angle of the second spectrometer is changed in accordance with the change of the focal length of the second spectrometer by the relay optical system. Characteristic measuring device. The optical characteristic measuring device according to claim 1, wherein the first accuracy of the first spectrometer is higher than the second accuracy of the second spectrometer. A light receiving optical system for condensing light to be measured from the object to be measured,
An optical member that guides the measured light that has passed through the light receiving optical system to the first and second spectrometers;
A first spectral measurement unit that spectrally measures the measured light that has passed through the light receiving optical system,
A second spectroscopic measurement unit that disperses the light to be measured that has passed through the light receiving optical system and measures the light with lower accuracy than the accuracy of the first spectrometer;
A first image formed by the light receiving optical system is provided between the optical member and the second spectroscopic measurement unit to reconverge into a second image, and a focal length of the second spectroscopic measurement unit is variable. Relay optics
An optical property calculation unit for obtaining a predetermined optical property of the measured light based on the first and second measurement results of the first and second spectrometers, respectively. The optical characteristic calculating unit corrects the second measurement result of the second spectroscopic measurement unit with the first measurement result of the first spectroscopic measurement unit to obtain a predetermined optical characteristic of the measured light. The optical characteristic measuring device according to claim 2 or 3, wherein The second spectrometer includes a two-dimensional sensor having a plurality of pixels arranged in a two-dimensional array and receiving the light to be measured by the plurality of pixels,
An area processing unit that obtains one or a plurality of pixels corresponding to a first region measured at a first measurement angle of the first spectral measurement unit from the plurality of pixels in the two-dimensional sensor,
The optical property calculation unit calculates the second measurement result of the second spectrometry unit based on a pixel value of the one or more pixels obtained by the area processing unit, The optical characteristic measuring apparatus according to claim 4, wherein a correction coefficient for correcting with one measurement result is obtained. The first spectroscopic measurement unit performs spot measurement that measures the light to be measured as one point and outputs one measurement result,
The said 2nd spectroscopic measurement part performs the two-dimensional measurement which measures the said to-be-measured light in two dimensions and outputs the measurement result of a two-dimensional distribution, The Claim 1 characterized by the above-mentioned. Item 2. The optical characteristic measuring device according to item 1. First and second spectroscopic measurement steps of spectroscopically measuring the light to be measured with first and second precisions different from each other;
An optical property calculating step of obtaining a predetermined optical property of the measured light based on the first and second measurement results of the first and second spectroscopic measurement steps, respectively.
In the second spectroscopic measurement step, the light to be measured is measured two-dimensionally as a surface, and the first image is re-converged to a second image , and the first image is measured via a relay optical system that varies the focal length. An optical characteristic measuring method, wherein a ratio between a measuring angle in the measuring step and a measuring angle in the second spectroscopic measuring step is changed.

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