JP6750189B2 - Optical property measuring device - Google Patents

Description

The present invention relates to an illumination mechanism and an optical characteristic measuring device.

The colorimeter is used to quantitatively measure the color of industrial products, foods, and the like. In the colorimeter, the sample is illuminated with the light beam of the illumination light, the light amount of the light beam of the reflected light reflected by the sample is measured, and the color value is derived from the measurement result. In the colorimeter, the variation of the light quantity of the light flux of the illumination light is monitored, and when the color value is derived, the correction of canceling the variation of the light quantity of the light flux of the illumination light is performed. For example, in the technique described in Patent Document 1, the bundle of rays emitted by a light source is limited by a diaphragm, and the limited bundle of rays is separated into a bundle of illumination light and a bundle of reference light by a beam splitter. The amount of reflected light beam and the amount of reference light beam are measured.

Chinese Patent Application Publication No. 101907493

In the technique described in Patent Document 1, since the light flux is limited by the diaphragm, the light flux is separated into the light flux of the illumination light and the light flux of the reference light by the beam splitter, so that the light amount of the light flux is reduced. After that, the bundle of rays is separated into a bundle of illumination light and a bundle of reference light. Therefore, in the measurement of the light quantity of the light flux of the reference light, when the light flux of the reference light having a sufficient light quantity to obtain a sufficient signal-to-noise ratio of the measurement is obtained, the light beam of the illumination light having a sufficient light quantity is obtained. Since the bundle cannot be obtained, the signal-to-noise ratio of the measurement deteriorates in the measurement of the light quantity of the bundle of reflected light. This problem can be solved if the amount of light flux emitted by the light source is increased, but the power consumption of the light source increases. These problems also occur in optical characteristic measuring devices other than the colorimeter.

The invention described below is made to solve these problems. The problem to be solved by the invention described below is to obtain both a ray bundle of illumination light having a sufficient light quantity and a ray bundle of reference light having a sufficient light quantity without increasing the power consumption of the light source. is there.

The optical characteristic measuring device includes an illumination mechanism, a first light receiving mechanism that receives a light beam bundle of reflected light reflected by the sample or a light beam bundle of transmitted light that has passed through the sample, and outputs a result of the first measurement. A second light receiving mechanism that receives a light beam bundle of light and outputs a result of the second measurement, and a deriving unit that performs correction based on the second measurement result and derives an optical characteristic from the first measurement result. In the illumination mechanism, the emission mechanism includes a discharge lamp and emits a light beam bundle. The beam splitter transmits the light flux of the illumination light and reflects the light flux of the reference light when the light flux emitted by the radiation mechanism enters. The diaphragm limits the bundle of illumination light that passes through the beam splitter. A diffuser plate is provided, and the diffused light beam diffused by the diffuser plate is incident on the beam splitter.

Both a ray bundle of illumination light having a sufficient light quantity and a ray bundle of reference light having a sufficient light quantity can be obtained without increasing the power consumption of the light source.

It is a schematic diagram which shows a colorimeter. It is sectional drawing which shows a measuring mechanism. It is sectional drawing which shows the light beam separation mechanism and the light-receiving mechanism for reference light. It is sectional drawing which shows the integrating sphere and the light-receiving mechanism for reflected light. It is sectional drawing which shows the integrating sphere and the light-receiving mechanism for reflected light. It is sectional drawing which shows another example of a measuring mechanism. It is sectional drawing which shows a beam splitter. It is sectional drawing which shows another example of the light beam separation mechanism and the light-receiving mechanism for reference light.

(1) Outline The schematic diagram of FIG. 1 shows a colorimeter. The schematic view of FIG. 2 shows a vertical section of a measuring mechanism that constitutes a colorimeter. The schematic view of FIG. 3 shows a cross section of a light beam separating mechanism and a reference light receiving mechanism that constitute a colorimeter. The schematic views of FIGS. 4 and 5 show cross sections of an integrating sphere and a light receiving mechanism for reflected light that constitute a colorimeter. FIG. 5 is an enlarged view showing the vicinity of the light receiving mechanism for reflected light.

The colorimeter 1000 shown in FIG. 1 includes a measuring mechanism 1010 and a controller 1011. As shown in FIGS. 1 and 2, the measurement mechanism 1010 includes an illumination mechanism 1020, an integrating sphere 1021, a light receiving mechanism 1022 for reflected light, and a light receiving mechanism 1023 for reference light. The illumination mechanism 1020 includes a radiation mechanism 1030, a light beam splitting mechanism 1031 and an image forming optical system 1032. The radiation mechanism 1030 and the imaging optical system 1032 configure an illumination optical system. The radiation mechanism 1030 and the light beam splitting mechanism 1031 form a reference optical system.

The radiating mechanism 1030 radiates a diffused ray bundle. The diffused light ray bundle is a light ray bundle that is uniformized by being diffused and reflected, and is preferably a light ray bundle that is uniformized by being diffused and multiple reflected. The ray bundle separation mechanism 1031 separates the emitted diffused ray bundle into a ray bundle 1041 of illumination light and a ray bundle 1042 of reference light. The image forming optical system 1032 forms an image of the light beam bundle 1041 of the illumination light. Accordingly, the illumination mechanism 1020 illuminates the sample with the light beam bundle 1041 of the illumination light.

The integrating sphere 1021 diffuses and reflects the ray bundle 1043 of the reflected light reflected by the sample, and then guides it to the light receiving mechanism 1022 for the reflected light. The light receiving mechanism 1022 for reflected light receives the light beam bundle 1043 of the reflected light and outputs the measurement results of the tristimulus values X, Y, and Z of the reflected light. The light receiving mechanism 1023 for reference light receives the light beam bundle 1042 of the reference light and outputs the measurement results of the tristimulus values X, Y, and Z of the reference light. Accordingly, the measurement mechanism 1010 outputs the measurement result of the tristimulus values X, Y and Z of the reflected light and the measurement result of the tristimulus values X, Y and Z of the reference light.

The controller 1011 controls the emission of the diffused ray bundle by the emission mechanism 1030. Further, the controller 1011 acquires the measurement result of the tristimulus values X, Y and Z of the reflected light and the measurement result of the tristimulus values X, Y and Z of the reference light, and the tristimulus values X, Y and Z of the reflected light. The color value is derived from the measurement result of. When the color value is derived, correction is performed based on the measurement results of the tristimulus values X, Y, and Z of the reference light. As a result, the color value is less likely to be affected by the fluctuation of the illumination light.

(2) Radiation Mechanism The radiation mechanism 1030 includes a pulse xenon lamp 1050, a reflector 1051 and a diffusion plate 1052. The pulse xenon lamp 1050 emits a bundle of rays. The reflector 1051 diffusely reflects the light flux. The diffusing plate 1052 diffuses the light ray bundle into a diffuse light ray bundle.

The pulse xenon lamp 1050 emits a flash of light. When a flash of light is emitted, the sample is illuminated with a large amount of light for a short time, improving the signal-to-noise ratio of the measurement. The pulse xenon lamp 1050 may be replaced by other types of light sources. For example, the pulse xenon lamp 1050 may be replaced with a tungsten lamp, a light emitting diode, or the like.

The reflector 1051 has a diffuse reflection surface 1060. The reflecting umbrella 1051 may be replaced with a reflecting mirror having a shape that is difficult to call an umbrella.

When the pulse xenon lamp 1050 emits a bundle of rays, the bundle of rays emitted toward the diffusing plate 1052 is diffused by the diffusing plate 1052 to be a bundle of diffusing rays. Further, the light flux emitted toward the diffuse reflection surface 1060 is diffused and reflected by the diffuse reflection surface 1060 to be a diffuse light flux, and the light flux emitted from the diffuse reflection surface 1060 toward the diffuser plate 1052 is a diffuser plate. It is diffused to 1052 and is made into a uniformized diffused ray bundle. Thereby, the light flux emitted by the pulse xenon lamp 1050 is efficiently used.

The pulse xenon lamp 1050 is a discharge lamp. In the discharge lamp, since the discharge path is different for each flash emission, the emission source of the flash is different for each flash emission. In the radiation mechanism 1030, since the light flux emitted by the pulse xenon lamp 1050 is diffused and reflected by the diffuse reflection surface 1060 and diffused by the diffuser plate 1052, the diffused light flux is less likely to be affected by the flash radiation source.

(3) Ray bundle separation mechanism As shown in FIGS. 2 and 3, the ray bundle separation mechanism 1031 includes a prismatic tubular structure 1070, a beam splitter 1071, and an attachment mechanism 1072.

The space 1080 formed in the rectangular tubular structure 1070 is defined by the inner peripheral surface 1090 of the rectangular tubular structure 1070, and has an entrance 1100 at one end and an exit 1101 at the other end. The shape of the cross section of the space 1080, which is perpendicular to the optical axis direction indicated by the arrow 1110, is rectangular, and is constant even when proceeding in the optical axis direction. The space 1080 extends straight in the optical axis direction and extends from the entrance 1100 to the exit 1101.

The inner peripheral surface 1090 has an antireflection surface 1120. Since the inner peripheral surface 1090 has the antireflection surface 1120, it is possible to prevent the light flux reflected by the inner peripheral surface 1090 from becoming a light flux of stray light. Desirably, the entire inner peripheral surface 1090 is the antireflection surface 1120, but the inner peripheral surface 1090 may have a slight surface that is not the antireflection surface 1120. The antireflection surface 1120 is a surface coated with black matte paint. The antireflection surface 1120 may be formed by roughening the black inner peripheral surface 1090.

The openings 1130, 1131 and 1132 formed in the rectangular tubular structure 1070 have inlets 1140, 1141 and 1142 at one end and outlets 1150, 1151 and 1152 at the other ends, respectively. From the inner peripheral surface 1090 of 1070 to the outer peripheral surface 1091 of the rectangular tubular structure 1070. The inlets 1140, 1141 and 1142 are on the inner peripheral surface 1090. The outlets 1150, 1151 and 1152 are on the outer peripheral surface 1091. The openings 1130, 1131 and 1132 extend in a direction perpendicular to the optical axis direction.

The beam splitter 1071 has a flat plate shape. The beam splitter 1071 is supported by the rectangular tubular structure 1070, is housed in the space 1080, and is arranged on the optical axis. Accordingly, when the diffused light flux emitted by the radiation mechanism 1030 is incident on the entrance 1100, the diffused light flux incident on the entrance 1100 is incident on the beam splitter 1071. The entrance surface of the beam splitter 1071 faces an intermediate direction between the direction toward the entrance 1100 and the directions toward the entrances 1140, 1141 and 1142. As a result, when a diffused ray bundle is incident on the beam splitter 1071, a main part of the incident diffused ray bundle is transmitted through the beam splitter 1071 and emitted from the emission port 1101 to become an illumination light ray bundle 1041. The rest of the bundle of rays incident on the beam splitter 1071 is reflected by the beam splitter 1071, enters the inlets 1140, 1141 and 1142, and exits from the outlets 1150, 1151 and 1152, and becomes the bundle of rays 1042 of the reference light. The ratio between the intensity of the light beam bundle 1041 of the illumination light and the intensity of the light beam bundle 1042 of the reference light is adjusted by the reflectances of the incident surface and the emission surface of the beam splitter 1071 serving as the reflecting surface that reflects the light beam bundle.

From the outlets 1150, 1151 and 1152, the entrance 1100 cannot be seen through, but only the beam splitter 1071 can be seen through. When one position is seen through from another position, it means that there is no light ray blocker on the straight line connecting the one position and the other position, and the light ray directly reaches from the other position to the one position. Say. When only the beam splitter 1071 can be seen through the exits 1150, 1151 and 1152, stray light ray bundles are unlikely to be mixed into the reference light ray bundle 1042 emitted from the outlets 1150, 1151 and 1152.

The rectangular tubular structure 1070 may be replaced with another type of structure. For example, the rectangular tubular structure 1070 may be replaced with a cylindrical structure.

A light receiving mechanism 1023 for reference light is attached to the attachment mechanism 1072.

(4) Imaging Optical System The imaging optical system 1032 includes a field stop 1160, an aperture stop 1161, a lens 1162, and a lens barrel 1163, as shown in FIG. The field stop 1160 and the aperture stop 1161 limit the ray bundle 1041 of the illumination light. The lens 1162 forms an image of the light beam bundle 1041 of the illumination light. The lens barrel 1163 supports the field stop 1160, the aperture stop 1161 and the lens 1162. The field stop 1160 adjusts the field of view illuminated by the bundle of illumination light rays 1041. The numerical aperture is adjusted by the aperture stop 1161.

Optical elements other than the field stop 1160, the aperture stop 1161 and the lens 1162 may be added to the imaging optical system 1032. For example, as shown in FIG. 6, a diffusion plate 1164 may be added before the aperture stop 1161.

The imaging optical system 1032 may be replaced by a collimating optical system that collimates the light beam bundle 1041 of the illumination light.

(5) Positional Relationship between Beam Splitter and Aperture The beam splitter 1071 is arranged closer to the pulse xenon lamp 1050 than the field stop 1160 and the aperture stop 1161. More generally, the beam splitter 1071 is preferably arranged on the pulse xenon lamp 1050 side with respect to all diaphragms provided in the section from the pulse xenon lamp 1050 to the sample, and is arranged at least on the pulse xenon lamp 1050 side with respect to the field diaphragm 1160. To be done.

When the beam splitter 1071 splits the light beam bundle into the illumination light beam bundle 1041 and the reference light beam bundle 1042 before the beam bundle is limited by the diaphragm, the light beam bundle incident on the beam splitter 1071 has a sufficient light amount. Therefore, even if the reflectance of the beam splitter 1071 is lowered, the light flux 1042 of the reference light having a sufficient light amount can be obtained. When the light beam bundle 1042 of the reference light having a sufficient light amount is obtained, the signal-to-noise ratio of the measurement in the light receiving mechanism 1023 for the reference light becomes sufficient. Decreasing the reflectance of the beam splitter 1071 means increasing the transmittance of the beam splitter 1071 and thus contributes to obtaining the light beam bundle 1041 of the illumination light having a sufficient light amount. Therefore, in the illumination mechanism 1020, both the light beam bundle 1041 of the illumination light having a sufficient light amount and the light beam bundle 1042 of the reference light having a sufficient light amount can be obtained without increasing the power consumption of the pulse xenon lamp 1050. Obtaining the luminous flux 1041 of the illumination light having a sufficient amount of light may be used for improving the signal-to-noise ratio of the measurement in the light receiving mechanism 1022 for reflected light, or the power consumption of the pulse xenon lamp 1050. May be used to suppress

When the ray bundle is separated after being limited, the position where the ray bundle 1042 of the reference light is separated is farther from the sample than when the ray bundle is separated before being limited. However, even in such a case, the correlation between the light amount of the light beam bundle 1041 of the illumination light and the light amount of the light beam bundle 1042 of the reference light is maintained, and the influence on the correction is small.

(6) Antireflection Film In the illumination mechanism 1020, the light flux 1042 of the reference light having a sufficient light quantity can be obtained even when the reflectance of the beam splitter 1071 is low. Therefore, in order to obtain a sufficient signal-to-noise ratio for measurement in the light receiving mechanism 1022 for reflected light, the reflectance of the beam splitter 1071 is lowered, that is, the transmittance of the beam splitter 1071 is increased. Therefore, it is desired to obtain the light beam bundle 1041 of the illumination light having a sufficient light amount.

When the reflectances of the entrance surface and the exit surface of the beam splitter made of only the base material are sufficiently low, the beam splitter made of only the base material may be adopted as the beam splitter 1071, but preferably the base material and the antireflection film. A beam splitter including is adopted as the beam splitter 1071.

The schematic view of FIG. 7 shows a cross section of a beam splitter including a substrate and an antireflection film.

The beam splitter 1071 shown in FIG. 7 includes a base material 1380 and antireflection films 1381 and 1382. The antireflection films 1381 and 1382 are formed on the one main surface 1390 and the other main surface 1391 of the base material 1380, respectively. The reflection suppressing films 1381 and 1382 make the reflectances of the entrance surface 1400 and the exit surface 1401 of the beam splitter 1071 lower than the reflectances of the entrance surface and the exit surface of the beam splitter including only the base material 1380, respectively. Each of the antireflection films 1381 and 1382 may be a single layer or a plurality of layers. One of the antireflection films 1381 and 1382 may be omitted.

(7) Specific Example of Light Amount of Light Beam of Illumination Light and Light Amount of Light Beam of Reference Light In the following, it is assumed that the refractive index of the base material 1380 is about 1.5. A refractive index of about 1.5 is that of glass, which is a typical material for substrate 1380.

When the beam splitter made of only the base material 1380 is adopted, the reflectance of each of the incident surface and the emission surface of the beam splitter made of only the base material 1380 is about 4%. The ratio of the reference light beam to the light amount of the light beam bundle is approximately 8:92.

On the other hand, when the beam splitter 1071 including the base material 1380 and the reflection suppressing films 1381 and 1382 is adopted, the reflection suppressing films 1381 and 1382 respectively reflect the incident surface 1400 and the emitting surface 1401 of the beam splitter 1071. The ratio is expected to decrease to about 2%, and the ratio of the light amount of the illumination light beam bundle to the reference light beam bundle is approximately 4:96.

Therefore, regardless of the presence or absence of the reflection suppressing films 1381 and 1382, a light flux of illumination light having a light intensity of about 92% or more of the light flux of the light flux incident on the beam splitter can be obtained, and the light flux of the light flux incident on the beam splitter can be obtained. A ray bundle of the reference light having a light amount of about 4% or more is obtained. Before the bundle of rays is limited by the field stop 1160 and the aperture stop 1161, the bundle of rays is separated into a bundle of rays 1041 of illumination light and a bundle of rays of reference light 1042 by the beam splitter 1071. When the light beam bundle 1042 of the reference light having the light amount of about 4% or more of the light amount is obtained, the signal-to-noise ratio of the measurement in the reference light receiving mechanism 1023 becomes sufficient. Therefore, when the light beam bundle is separated by the beam splitter 1071 into the light beam bundle 1041 of the illumination light and the light beam bundle 1042 of the reference light before the light beam bundle is limited by the field stop 1160 and the aperture stop 1161, A light beam bundle 1041 of illumination light having a light amount of about 92% or more of the light amount of the light beam incident on the beam splitter 1071 is obtained while the measurement signal-to-noise ratio is made sufficient in the light receiving mechanism 1023.

On the other hand, when the light beam bundle is limited by the field stop 1160 and the aperture stop 1161 and then separated by the beam splitter 1071 into the light beam bundle of the illumination light and the light beam of the reference light, the reference light is received. When the measurement signal-to-noise ratio is set to be sufficient in the mechanism 1023, only the luminous flux of the illumination light having the luminous energy of about 50% of the luminous flux of the luminous flux incident on the beam splitter 1071 can be obtained. Further, even at the sacrifice of making the measurement signal-to-noise ratio sufficient in the reference light receiving mechanism 1023, the illumination light having the light amount of about 75% of the light amount of the light flux incident on the beam splitter 1071 is obtained. You can only get a bundle of rays. Therefore, when the light beam bundle is limited by the field stop 1160 and the aperture stop 1161 and then separated by the beam splitter 1071 into the light beam bundle of the illumination light and the light beam of the reference light, the light receiving mechanism 1023 for the reference light performs measurement. Even at the expense of making the signal-to-noise ratio sufficient, a ray bundle of illumination light having a sufficient amount of light cannot be obtained.

When the light bundle is separated before the light bundle is limited, the utilization efficiency of the light bundle is reduced due to the limitation of the light bundle after the light bundle is separated. However, even if the ray bundles are separated after the ray bundles are limited, the utilization efficiency of the ray bundles is reduced due to the limitation of the ray bundles before the ray bundles are separated, so In the above comparison between the case where the bundle of rays is separated and the case where the bundle of rays is separated after the bundle of rays is limited, the reduction in the utilization efficiency of the bundle of rays due to the limitation of the bundle of rays can be almost ignored.

(8) Integrating Sphere The integrating sphere 1021 is a hollow spherical structure as shown in FIGS. 2 and 4.

The space 1170 formed in the integrating sphere 1021 is defined by the inner surface 1180 of the integrating sphere 1021. The shape of the space 1170 is spherical. The sample window 1190 formed on the integrating sphere 1021 is seen through the illumination window 1191 formed on the integrating sphere 1021. The sample window 1190 and the illumination window 1191 cannot be seen through the light receiving window 1192 formed in the integrating sphere 1021. A lighting mechanism 1020 is coupled to the lighting window 1191. A light receiving mechanism 1022 for reflected light is attached to the light receiving window 1192.

The inner surface 1180 has a diffuse reflection surface 1200. Desirably, the entire inner surface 1180 is the diffuse reflection surface 1200, but the inner surface 1180 may have a few surfaces that are not the diffuse reflection surface 1200.

The diffuse reflection surface 1200 is a surface coated with white matte paint. White matte paints include resins, white pigments, matte materials, and the like. The resin is acrylic resin or the like. The white pigment is powder of titanium oxide, zinc oxide, barium sulfate, calcium carbonate or the like. The matting material is fine particles of silica, calcium carbonate, calcium phosphate or the like. The white matte paint may be replaced by an achromatic matte paint other than white. The diffuse reflection surface 1200 may be formed by roughening the inner peripheral surface 1180.

When the illumination mechanism 1020 emits the light beam bundle 1041 of the illumination light, the light beam bundle 1041 of the illumination light enters the illumination window 1191, travels through the space 1170 without being reflected by the inner surface 1180, and reaches the sample window 1190. When there is a sample in the sample window 1190, the sample is illuminated by the light beam bundle 1041 of the illumination light reaching the sample window 1190, and the sample reflects the light beam bundle 1043 of the reflected light. The ray bundle 1043 of the reflected light propagates in the space 1170, is diffusely reflected by the diffuse reflection surface 1200 while propagating in the space 1170, and is emitted from the light receiving window 1192.

(9) Light-Reception Mechanism for Reflected Light The light-reception mechanism 1022 for reflected light includes a sensor unit 1210 as shown in FIG.

The sensor unit 1210 includes filters 1220, 1221 and 1222, diaphragms 1230, 1231 and 1232, light receiving sensors 1240, 1241 and 1242, and a structure 1250.

The filters 1220, 1221 and 1222 are inserted into the holes 1260, 1261 and 1262 formed in the structure 1250, respectively, and are supported by the structure 1250. The diaphragms 1230, 1231 and 1232 are inserted into the holes 1260, 1261 and 1262 formed in the structure 1250, respectively, and are supported by the structure 1250. The light receiving sensors 1240, 1241 and 1242 are inserted into the holes 1260, 1261 and 1262, respectively, and are supported by the structure 1250.

The diaphragm 1270, the filter 1220, the diaphragm 1230, and the light receiving sensor 1240 formed on the structure 1250 constitute a light receiving optical system that measures the stimulus value X. The diaphragm 1271, the filter 1221, the diaphragm 1231 and the light receiving sensor 1241 formed on the structure 1250 constitute a light receiving optical system for measuring the stimulation value Y. The diaphragm 1272, the filter 1222, the diaphragm 1232, and the light receiving sensor 1242 formed on the structure 1250 constitute a light receiving optical system that measures the stimulation value Z.

The common points of the light receiving optical system for measuring the stimulus value X, the light receiving optical system for measuring the stimulus value Y, and the light receiving optical system for measuring the stimulus value Z will be described by taking the light receiving optical system for measuring the stimulus value Y as an example.

The diaphragm 1271, the filter 1221, the diaphragm 1231 and the light receiving sensor 1241 are arranged in the order described.

When the bundle of reflected light rays 1043 enters the hole 1261, the bundle of reflected light rays 1043 travels through the hole 1261 and passes through the diaphragm 1271, the filter 1221 and the diaphragm 1231 in the order described while proceeding through the hole 1261. The light is received by the light receiving sensor 1241. The diaphragms 1271 and 1231 limit the ray bundle 1043 of the reflected light. The light receiving sensor 1241 receives the ray bundle 1043 of reflected light and outputs a signal according to the amount of received light. Thereby, the stimulation value Y is measured. The diaphragms 1271 and 1231 reduce the angle of incidence of the bundle of reflected light rays 1043 on the filter 1221. That is, the bundle of reflected light rays 1043 is incident on the filter 1221 substantially vertically.

(10) Light Receiving Mechanism for Reference Light The light receiving mechanism 1023 for reference light includes a diffusion plate 1280 and a sensor unit 1281 as shown in FIG.

The diffusion plate 1280 is arranged between the openings 1130, 1131 and 1132 and the sensor unit 1281 and diffuses the light beam bundle 1042 of the reference light.

The sensor unit 1281 includes filters 1290, 1291 and 1292, diaphragms 1300, 1301 and 1302, light receiving sensors 1310, 1311 and 1312, and a structure 1320. In the structure 1320, diaphragms 1330, 1331 and 1332 are formed, and holes 1340, 1341 and 1342 are formed.

The sensor unit 1281 is the same type as the sensor unit 1210. The fact that the sensor unit 1281 is the same type as the sensor unit 1210 reduces the manufacturing cost of the colorimeter 1000.

When the light receiving mechanism 1023 for reference light receives the light beam bundle 1042 of reference light, the diffusion plate 1280 diffuses the light beam bundle 1042 of reference light. The diffused light beam 1042 of the reference light enters the holes 1340, 1341 and 1342. The diffusing plate 1280 causes a part of the light beam bundle traveling from the exits 1150, 1151 and 1152 in a direction other than the direction toward the light receiving sensors 1310, 1311 and 1312 toward the light receiving sensors 1310, 1311 and 1312, thereby improving the signal-to-noise ratio of measurement. It

When the sensor unit 1281 is the same type as the sensor unit 1210, since the sensor unit 1281 has the diaphragms 1300, 1301 and 1302 and the diaphragms 1330, 1331 and 1332, the light receiving sensors 1310, 1311 and 1312 are output from the outlets 1150, 1151 and 1152. Installed separately. When the light receiving sensors 1310, 1311 and 1312 are installed apart from the outlets 1150, 1151 and 1152, the light fluxes from the outlets 1150, 1151 and 1152 to directions other than the direction toward the light receiving sensors 1310, 1311 and 1312 are increased, The light flux received by the light receiving sensors 1310, 1311 and 1312 is reduced, and the signal-to-noise ratio of the measurement is deteriorated. The diffuser plate 1280 suppresses such a decrease in the received light flux.

The sensor unit 1281 may be replaced with a sensor unit that is not the same type as the sensor unit 1210. When the sensor unit 1281 is replaced with a sensor unit that is not the same type as the sensor unit 1210, the sensor unit 1281 is preferably replaced with a sensor unit that does not include a diaphragm.

In the colorimeter 1000, the beam splitter 1071 separates the light bundle into the light bundle 1041 of the illumination light and the light bundle 1042 of the reference light before the light bundle is limited by the field stop 1160 and the aperture stop 1161. The cross-sectional shape of the light ray bundle 1042 is not affected by the shapes of the field stop 1160 and the aperture stop 1161. Therefore, it is not necessary to adapt the structure of the light receiving mechanism 1023 for reference light to the shapes of the field stop 1160 and the aperture stop 1161.

On the other hand, when the light beam bundle is limited by the field stop 1160 and the aperture stop 1161 and then separated by the beam splitter 1071 into the light beam bundle of the illumination light and the light beam of the reference light, the light beam of the reference light Since the cross-sectional shape of the bundle is influenced by the shapes of the field stop 1160 and the aperture stop 1161, the structure of the light receiving mechanism 1023 for the reference light is adapted to the shape of the field stop 1160 and the aperture stop 1161, or the beam of the reference light. It is necessary to provide an optical system that adapts the cross-sectional shape of the bundle to the structure of the light receiving mechanism 1023 for reference light. For example, when the shapes of the field stop 1160 and the aperture stop 1161 are circular, the light receiving sensors 1310, 1311 and 1312 are arranged on the circumference, or the cross-sectional shape of the light flux of the reference light is converted into a linear shape. It becomes necessary to provide an optical system.

The schematic diagram of FIG. 8 shows a cross section of the light beam separation mechanism and the light receiving mechanism for reference light when the sensor unit is replaced with a sensor unit having no diaphragm.

The sensor unit 1350 shown in FIG. 8 includes light receiving sensors 1360, 1361 and 1362 and filters 1370, 1371 and 1372. The light receiving sensors 1360, 1361 and 1362 are installed close to the outlets 1150, 1151 and 1152.

(11) Change of measurement method The measurement method of the light receiving mechanism 1022 for reflected light and the light receiving mechanism 1023 for reference light may be changed from the tristimulus value method to the spectroscopic method. When the measuring method of the light receiving mechanism 1022 for reflected light and the light receiving mechanism 1023 for reference light is a spectroscopic method, each of the light receiving mechanism 1022 for reflected light and the light receiving mechanism 1023 for reference light is a diffraction grating, a prism, or the like. A polychromator having a wavelength dispersion element is provided. When the measuring method of the light receiving mechanism 1022 for reflected light and the light receiving mechanism 1023 for reference light is changed to the spectroscopic method, each of the light receiving mechanism 1022 for reflected light and the light receiving mechanism 1023 for reference light measures a spectrum. Then, the colorimeter becomes a spectrocolorimeter. Colorimeters are roughly classified into colorimeters and spectrophotometers.

(12) Measurement of Transmitted Light The light receiving mechanism 1022 for reflected light may be replaced with a light receiving mechanism for transmitted light. The transmitted light receiving mechanism receives the light flux of the transmitted light that has passed through the sample and outputs the measurement results of the tristimulus values X, Y, and Z of the transmitted light.

(13) Controller The controller 1011 is an embedded computer, and controls by executing firmware. All or part of the control by the controller 1011 may be realized by hardware without software.

The controller 1011 controls the pulse xenon lamp 1050 so that the pulse xenon lamp 1050 emits a light flux. Further, the controller 1011 acquires the tristimulus values X, Y and Z of the reflected light from the light receiving sensors 1240, 1241 and 1242, respectively, when the light flux is emitted from the pulse xenon lamp 1050, and the tristimulus value of the reference light. X, Y and Z are acquired from the light receiving sensors 1310, 1311 and 1312, respectively. Further, the controller 1011 derives a color value from the tristimulus values X, Y and Z of the reflected light. The color value is represented by the Munsell color system, the L ^* a ^* b ^* color system, the L ^* C ^* h color system, the Hunter Lab color system, the XYZ color system, and the like. When the color value is derived, the correction is performed using the tristimulus values X, Y and Z of the reference light. Optical characteristics other than the color value may be derived. For example, when the measurement method is the spectral method, the spectral reflectance, the spectral transmittance, etc. may be derived.

1000 Colorimeter 1010 Measuring mechanism 1020 Illuminating mechanism 1021 Integrating sphere 1022 Reflecting light receiving mechanism 1023 Reference light receiving mechanism 1030 Radiating mechanism 1031 Ray bundle separating mechanism 1032 Imaging optical system 1071 Beam splitter 1160 Field stop 1161 Aperture stop

Claims (6)

Lighting mechanism,
A first light receiving mechanism for receiving a ray bundle of reflected light reflected by the sample or a ray bundle of transmitted light transmitted through the sample and outputting a result of the first measurement;
A second light receiving mechanism for receiving the light flux of the reference light and outputting the result of the second measurement;
A deriving unit for deriving an optical characteristic from the first measurement result by performing correction based on the second measurement result,
Equipped with
The illumination mechanism is
A radiation mechanism that includes a discharge lamp and emits a light flux,
A beam splitter that transmits the light flux of the illumination light and reflects the light flux of the reference light when the light flux emitted by the radiation mechanism is incident,
A diaphragm for limiting the light flux of the illumination light transmitted through the beam splitter,
Equipped with
An optical characteristic measuring device having a diffusing plate, wherein a diffused light beam diffused by the diffusing plate is incident on the beam splitter. The optical characteristic measuring device according to claim 1, wherein the diaphragm is a field diaphragm, and a field illuminated by a bundle of illumination light is adjusted by the field diaphragm. The beam splitter is
A plate-shaped substrate having a main surface,
An antireflection film formed on the main surface,
The optical characteristic measuring device according to claim 1 or 2, further comprising: The optical characteristic measuring device according to any one of claims 1 to 3, wherein the illumination mechanism further includes an aperture stop that limits a light beam bundle of illumination light that has passed through the beam splitter, and the numerical aperture is adjusted by the aperture stop. The optical characteristic measuring device according to claim 1, wherein the stop is an aperture stop, and the numerical aperture is adjusted by the aperture stop. The optical characteristic measuring device according to claim 1, wherein the optical characteristic is a color value.

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