CN116113810A

CN116113810A - Optical device, color brightness meter and color meter

Info

Publication number: CN116113810A
Application number: CN202180057365.6A
Authority: CN
Inventors: 平尾祐亮; 小坂明; 中谷通; 植田真由
Original assignee: Konica Minolta Inc
Current assignee: Konica Minolta Inc
Priority date: 2020-08-07
Filing date: 2021-07-27
Publication date: 2023-05-12
Also published as: WO2022030292A1; KR20230025483A; JPWO2022030292A1

Abstract

The optical device is provided with a photometry unit (12A), a1 st optical unit (11A), a photometry unit (12B), and a2 nd optical unit (11B). The 1 st optical unit (11A) has a1 st lens (22A) closest to the object side, and a1 st prism (21A) that deflects light from the 1 st portion (AR 1) and guides the light to the 1 st lens. The 2 nd optical unit (11B) has a2 nd lens (22B) closest to the object side, and a2 nd prism (21B) that deflects light from the 2 nd portion (AR 2) and guides the light to the 2 nd lens (22B). The 1 st optical axis (AX 1) of the 1 st optical unit (11A) from the object (1) to the 1 st prism (21A) is substantially parallel to the 2 nd optical axis (AX 2) of the 2 nd optical unit (11B) from the object (1) to the 2 nd prism (21B), and the interval between the 1 st optical axis (AX 1) and the 2 nd optical axis (AX 2) is smaller than the distance between the center of the 1 st lens (22A) and the center of the 2 nd lens (22B).

Description

Optical device, color brightness meter and color meter

Technical Field

The present invention relates to an optical device, and a color luminance meter and a color meter using the optical device.

Background

Color-brightness meters that measure the color and brightness of a light emitter, as well as color meters that measure the color of an object, are known. For example, color brightness meters are used to measure and adjust the optical characteristics of a display.

The size of the display is varied according to the size of the electronic device on which the display is mounted. If the size of the display to be measured is small, the measurement range of luminance and chromaticity becomes small. On the other hand, the amount of light emitted from a certain measurement range of the object to be measured decreases as the measurement range becomes smaller. For this reason, an optical device for evaluation of an OLED (Organic Light Emitting Diode (organic light emitting diode)) display, for example, is configured to be capable of acquiring a larger amount of light from a small measurement range.

For example, international publication No. 2011/121896 (patent document 1) discloses a measurement optical system for a color luminance meter or a colorimeter measurement optical system. In this optical system for measurement, measurement light is split into a plurality of light fluxes, and each split light is received by a light receiving sensor via an interference film filter. The measuring optical system has an objective lens for condensing light. The objective lens has a circular shape

Is provided.

International publication No. 2018/230177 (patent document 2) discloses a measurement optical system for guiding a larger amount of light from a measurement object to a light receiving unit. The measuring optical system includes an aperture, an optical waveguide for guiding incident light, a1 st optical system, and a2 nd optical system. The 1 st optical system is disposed on the object side of the diaphragm, and forms an optical image from the measurement object on the aperture surface of the diaphragm. The 2 nd optical system is disposed between the aperture and the optical waveguide, and makes each principal ray of each light beam emitted from the aperture surface of the aperture enter the optical waveguide so that each principal ray becomes parallel to the optical axis.

Japanese patent laid-open publication No. 2003-247891 (patent document 3) discloses an optical device for suppressing as much as possible unevenness in the amounts of light emitted from a plurality of emission surfaces even when the orientation characteristics of an object to be measured are asymmetric. The optical device includes an optical branching unit. The light branching unit has a plurality of emission surfaces for branching and emitting light from the object to be measured incident on the incident surface. The incident surface of the light branching unit is divided into a plurality of incident areas. Light incident on a plurality of non-adjacent mutually different incident regions is emitted from the respective emission surfaces of the light branching unit.

Prior art literature

Patent literature

Patent document 1 International publication No. 2011/121896

Patent document 2 International publication No. 2018/230177

Patent document 3 Japanese patent laid-open No. 2003-247891

Disclosure of Invention

Problems to be solved by the invention

In recent years, in the field of displays, a technology called an under-screen camera (Under Screen Camera (USC)) is being developed. USC is a technology in which a camera module is arranged on the back of a display. This technique is sometimes referred to as an under-display camera (Under Display Camera), but in this specification, the corresponding technique is referred to by the name "USC".

Devices employing USCs have a structure in which it is difficult to see the camera across the display. In such a device, a portion of the display (referred to as USC portion) overlapping the camera has a structure different from that of a normal portion of the display (hereinafter referred to as normal portion). In the gamma adjustment of the display, it is therefore necessary to perform the gamma adjustment for the USC portion and the normal portion, respectively.

Further, in order to shorten the intermittent time, there is a demand for simultaneous measurement of the luminance of the USC portion and the luminance of the normal portion. However, there is a light emission distribution in the face of the display. Therefore, the normal portion to be measured is desirably a portion as close to the USC portion as possible. In this case, it is required to measure the luminance of 2 parts close to each other such that the interval between the USC part and the normal part is 10mm.

In general, 2 luminometer probes (probes) are required to measure the brightness of 2 parts of the luminophore simultaneously. In order to measure the brightness of 2 sites in proximity at the same time, 2 luminometer probes must be brought close together. However, due to physical size limitations, it is difficult to closely arrange existing luminometer probes (e.g. arranged at intervals of 10 mm). On the other hand, when the size of each of the 2 luminance probe needles is reduced in order to reduce the distance between the luminance probe needles, the aperture of the lens positioned closest to the object side is reduced, and the amount of light acquired by the luminance probe needles is reduced.

The present invention has been made in view of the above circumstances, and an object thereof is to provide an optical device capable of measuring luminance in a portion close thereto while maintaining brightness, and a color luminance meter and a color meter using the optical device.

Unit for solving the problem

In order to solve the above problems, an optical device according to an aspect of the present invention includes: a1 st photometry section for receiving light from a1 st part of the object, a1 st optical unit, a2 nd photometry section for receiving light from a2 nd part of the object, and a2 nd optical unit. The 1 st optical unit has: the optical device includes a1 st lens which is a lens closest to an object side of a1 st photometry section for condensing light from a1 st part, and a1 st optical component for guiding the light from the 1 st part to the 1 st lens by deflecting the light. The 2 nd optical unit has: a2 nd lens which is a lens closest to the object side of the 2 nd photometry section for condensing the light from the 2 nd part, and a2 nd optical component which deflects the light from the 2 nd part and guides the light to the 2 nd lens. The optical axis of the 1 st optical unit from the object to be measured to the 1 st optical member is substantially parallel to the optical axis of the 2 nd optical unit from the object to be measured to the 2 nd optical member, and the interval between the optical axis of the 1 st optical unit and the optical axis of the 2 nd optical unit is smaller than the distance between the center of the 1 st lens and the center of the 2 nd lens.

A color luminance meter and a color meter according to another aspect of the present invention include the optical device described above.

Effects of the invention

According to the present invention, it is possible to provide an optical device capable of measuring brightness in a portion close to the optical device while maintaining brightness, and a color luminance meter and a color meter using the optical device.

Drawings

Fig. 1 is a block diagram showing a schematic configuration of a color luminance meter in which an optical device according to an embodiment of the present invention is mounted.

Fig. 2 is a block diagram showing a schematic configuration of a colorimeter in which an optical device according to an embodiment of the present invention is mounted.

Fig. 3 is a block diagram showing a configuration example of an optical device according to an embodiment of the present invention.

Fig. 4 is a schematic diagram showing an example of the object to be measured.

Fig. 5 is a diagram showing a structure of an optical device according to embodiment 1 of the present invention.

Fig. 6A is an oblique view of a parallelepiped prism according to embodiment 1 of the present invention.

Fig. 6B is a front view of a parallelepiped prism according to embodiment 1 of the present invention.

Fig. 6C is a top view of a parallelepiped prism according to embodiment 1 of the present invention.

Fig. 7 is a diagram showing a state in which 2 parallelepiped prisms are closely arranged.

Fig. 8 is a diagram showing a structure of an optical device according to embodiment 2 of the present invention.

Fig. 9A is an oblique view of a parallelepiped prism according to embodiment 2 of the present invention.

Fig. 9B is a front view of a parallelepiped prism according to embodiment 2 of the present invention.

Fig. 9C is a top view of a parallelepiped prism according to embodiment 2 of the present invention.

Fig. 10 is a diagram showing a structure of an optical device according to embodiment 3 of the present invention.

Fig. 11A is a perspective view of a triangular prism according to embodiment 3 of the present invention.

Fig. 11B is a front view of a triangular prism according to embodiment 3 of the present invention.

Fig. 11C is a side view of a triangular prism according to embodiment 3 of the present invention.

Detailed Description

Hereinafter, embodiments of the present invention will be described with reference to the drawings. The same or corresponding parts in the drawings are denoted by the same reference numerals, and description thereof will not be repeated.

Fig. 1 is a block diagram showing a schematic configuration of a color luminance meter in which an optical device according to an embodiment of the present invention is mounted. In the embodiment shown in fig. 1, the object 1 to be measured is a light emitting body that emits light, and may be, for example, a display or an electronic device having a display. The color luminance meter 101 according to an embodiment of the present invention can measure the color and luminance of the light emitting body of the object 1.

The color brightness meter 101 includes

probes

10A and 10B and a control processing unit 50. The probe 10A includes an optical unit 11A, a photometry section 12A, a signal processing section 13A, and a calculation section 14A. The optical unit 11A receives light from the 1 st part of the object 1, and guides the light to the photometry section 12A. The photometry section 12A photoelectrically converts light from the 1 st part of the object 1 to be measured and outputs an electric signal (analog signal) having an intensity corresponding to the intensity of the light. The signal processing section 13A includes an amplifier (not shown in fig. 1) that amplifies the light from the photometry section 12A and an a/D converter (not shown in fig. 1) that converts an analog signal from the amplifier into a digital signal (measurement data). The arithmetic unit 14A calculates a tristimulus value (X, Y, Z), xyY (chromaticity coordinates, luminance) formulated by CIE (international commission on illumination), tΔuvy (correlated color temperature, color difference from the blackbody locus, luminance), and the like by performing predetermined arithmetic processing using the digital signal (measurement data) output from the a/D converter.

The probe 10B has the same structure as the probe 10A. Specifically, the probe 10B includes an optical unit 11B, a photometry section 12B, a signal processing section 13B, and an arithmetic section 14B. The optical unit 11B receives light from the 2 nd portion of the object 1 to be measured, and guides the light to the photometry section 12B. The photometry section 12 receives light from the 2 nd part of the object 1. The functions of the respective blocks of the probe 10B are the same as those of the corresponding blocks of the probe 10A, and the description will not be repeated.

The control processing unit 50 includes a control unit 51, a display unit 52, an operation unit 53, and a storage unit 54. The control processing unit 50 is realized by a personal computer, for example. The control unit 51 controls the

probes

10A and 10B. Further, the control unit 51 can receive data from each of the

probes

10A and 10B, and perform processing such as display and management of the data. The display unit 52 displays the measurement data in the form of a chart, a list, or the like under the control of the control unit 51. The operation unit 53 receives various information (instruction of measurement, setting of display mode, measurement range, etc.) related to measurement. The storage unit 54 stores various data including measurement data.

The optical device according to the embodiment of the present invention can be applied to a colorimeter. Fig. 2 is a block diagram showing a schematic configuration of a colorimeter in which an optical device according to an embodiment of the present invention is mounted. The structure of the color meter 102 is basically the same as that of the color luminance meter 101, but is different from that of the color luminance meter 101 in that the illumination section 40 is added. The illumination unit 40 is a device that irradiates the object 1 with illumination light by a predetermined geometry (not limited thereto, for example, 45 °:0 °).

Fig. 3 is a block diagram showing a configuration example of an optical device according to an embodiment of the present invention. Fig. 3 mainly shows the structure of the optical unit and the photometry section included in the probe.

The optical unit 11A (1 st optical unit) includes an optical member 21A (1 st optical member), a lens 22A (1 st lens), and a beam splitter 23A. The lens 22A is a lens closest to the object side, and is a lens for condensing light from the 1 st part of the object 1 onto the photometry section 12A (1 st photometry section). The optical member 21A deflects the light from the 1 st part of the object 1 to guide the light to the lens 22A. The light flux splitting member 23A is an optical waveguide that splits the light flux transmitted through the lens 22A into 3 light fluxes and guides the light fluxes to the photometry section 12A. As the beam splitter 23A, for example, a bundle fiber (bundle fiber) can be used.

The photometry section 12A includes filters 24A-1, 24A-2, 24A-3 and sensors 25A-1, 25A-2, 25A-3. The filters 24A-1, 24A-2, 24A-3 are color filters, and transmit the light emitted from the beam splitter 23A with a predetermined transmittance characteristic. Specifically, the filters 24A-1, 24A-2, and 24A-3 are filters having spectral transmission characteristics corresponding to the isochromatic function X, Y, Z defined in CIE, for example, interference film filters. The sensors 25A-1, 25A-2, 25A-3 receive light transmitted through the filters 24A-1, 24A-2, 24A-3, respectively, and output an electrical signal corresponding to the received light intensity. The signals from the sensors 25A-1, 25A-2, 25A-3 are input to the signal processing section 13A.

The optical unit 11B (2 nd optical unit) has the same structure as the optical unit 11A. The optical unit 11B includes an optical member 21B (2 nd optical member), a lens 22B (2 nd lens), and a beam dividing member 23B.

The lens 22B is a lens closest to the object side, and is a lens for condensing light from the 2 nd portion of the object 1 onto the photometry section 12B (2 nd photometry section). The optical member 21B deflects the light from the 2 nd portion of the object 1 to be measured and guides the light to the lens 22B. The light flux splitting member 23B is an optical waveguide that splits the light flux transmitted through the lens 22B into 3 light fluxes and guides the light fluxes to the photometry section 12B.

The photometry section 12B has the same structure as the photometry section 12A. The photometry section 12B includes filters 24B-1, 24B-2, 24B-3 and sensors 25B-1, 25B-2, 25B-3. The filters 24B-1, 24B-2, and 24B-3 are filters having spectral transmission characteristics corresponding to the isochromatic function X, Y, Z defined in CIE, respectively. The sensors 25B-1, 25B-2, 25B-3 receive the electric signals transmitted through the filters 24B-1, 24B-2, 24B-3, respectively, and output electric signals corresponding to the received light intensities. The signals from the sensors 25B-1, 25B-2, 25B-3 are input to the signal processing section 13B.

Fig. 4 is a schematic diagram showing an example of the object to be measured. The object 1 to be measured is, for example, a smart phone, and has a display 2 using USC. However, a camera (not shown) is disposed behind the display 2. The measurement target parts on the display 2 are, for example, the 1 st part 3 (USC part) and the 2 nd part 4 (normal part). The 1 st part 3 and the 2 nd part 4 are close to each other, and the distance D (center-to-center distance) between the 1 st part 3 and the 2 nd part 4 is 10mm, for example.

In addition, although not limited thereto, in one embodiment, the minimum measurement width A1 of the 1 st portion 3 is a value greater than 0 and less than 3mm. Similarly, the minimum measurement width A2 of the 2 nd portion 4 is set to a value greater than 0 and less than 3mm.

(detailed description of the optical device according to the present embodiment)

The optical device according to the present embodiment may have a structure described below. The optical device includes a1 st photometry section for receiving light from a1 st part of the object, a1 st optical unit, a2 nd photometry section for receiving light from a2 nd part of the object, and a2 nd optical unit. The 1 st optical unit has a1 st lens for condensing light from the 1 st part on the object side of the 1 st photometry section, and a1 st optical component for deflecting and guiding the light from the 1 st part to the 1 st lens. The 2 nd optical unit has a2 nd lens for condensing light from the 2 nd portion on the object side of the 2 nd photometry section, and a2 nd optical member for deflecting and guiding the light from the 2 nd portion to the 2 nd lens. The optical axis of the 1 st optical unit from the object to be measured to the 1 st optical member is substantially parallel to the optical axis of the 2 nd optical unit from the object to be measured to the 2 nd optical member, and the interval between the optical axis of the 1 st optical unit and the optical axis of the 2 nd optical unit is smaller than the distance between the center of the 1 st lens and the center of the 2 nd lens.

According to this structure, the luminance of 2 parts arranged on the object to be measured can be measured at a smaller interval than the interval between the 1 st optical unit and the 2 nd optical unit. Further, since the 1 st lens and the 2 nd lens can use NA (aperture number) or lenses having a large effective aperture, the 1 st optical unit and the 2 nd optical unit can obtain a larger amount of light from the corresponding portions on the object to be measured, respectively. Thus, according to the present embodiment, an optical device capable of measuring color or brightness in an approaching portion on a measurement object while maintaining brightness can be provided. In the present specification, "substantially parallel" includes not only a case where 2 lines or 2 planes are exactly parallel, but also a case where one line (or plane) is inclined to the other line (or plane) at an angle within a predetermined range.

According to the present embodiment, the 1 st optical member and the 2 nd optical member reflect light from the object to be measured and guide the light to the 1 st lens and the 2 nd lens, respectively. According to this configuration, since the light from the approaching portion on the object to be measured can be bent, the 1 st optical unit and the 2 nd optical unit can guide the light from the corresponding portion on the object to be measured, respectively.

According to the present embodiment, the 1 st optical member totally reflects the light from the object to be measured 2 times to guide the light from the object to be measured to the 1 st lens, and the 2 nd optical member totally reflects the light from the object to be measured 2 times to guide the light from the object to be measured to the 2 nd lens. Preferably, the 1 st optical member and the 2 nd optical member each have an incident surface facing the object side, an exit surface facing a corresponding one of the 1 st lens and the 2 nd lens, a1 st reflection surface reflecting light incident on the incident surface, and a2 nd reflection surface reflecting light reflected by the 1 st reflection surface and guiding the light to the exit surface, the incident surface and the exit surface being substantially parallel, and the 1 st reflection surface and the 2 nd reflection surface being substantially parallel. According to this configuration, the 1 st optical member and the 2 nd optical member can bend and guide the light from the object to be measured to the corresponding lenses, respectively. Therefore, light from 2 sites arranged on the object to be measured can be guided to the 1 st optical unit and the 2 nd optical unit, respectively, at a smaller interval than that between the 1 st optical unit and the 2 nd optical unit.

According to the present embodiment, the 1 st optical member and the 2 nd optical member are each a parallelepiped prism, and the end portion of the parallelepiped prism connecting the incident surface of the parallelepiped prism and the 1 st reflection surface may be a chamfered end portion. According to this configuration, the 1 st optical member and the 2 nd optical member can bend the light from the object to be measured 2 times and guide the light to the corresponding lenses, respectively. Further, the 1 st optical member and the 2 nd optical member can be brought close to each other. Therefore, the brightness of the 2 portions close to each other on the object to be measured can be measured.

In addition, the mirror may deflect the light by reflecting the light. So that the 1 st and 2 nd optical components can also be realized by mirrors. However, in the case of using a mirror, the possibility that its reflection characteristics have polarization dependence needs to be considered. The prism is more advantageous than the mirror in that the prism can bend the light beam without polarization dependence.

In the present embodiment, the prism is located before the lens closest to the object side (object side) of the photometry section. The optical image of the measurement target portion rotates by total reflection from the prism. However, in the present embodiment, since the optical device is intended to receive a larger amount of light from the measurement target portion, the orientation of the optical image imaged by the lens closest to the object side does not directly affect the measurement of chromaticity or luminance.

According to the present embodiment, the 1 st optical member may totally reflect light from the object to be measured 1 time and guide the light from the object to be measured to the 1 st lens, and the 2 nd optical member may totally reflect light from the object to be measured 1 time and guide the light from the object to be measured to the 2 nd lens. Preferably, the 1 st optical member and the 2 nd optical member are triangular prisms, respectively, having an incident surface facing the object side, an exit surface facing a corresponding one of the 1 st lens and the 2 nd lens, and a2 nd reflection surface for totally reflecting and guiding light incident on the incident surface onto the exit surface.

According to the above configuration, the 1 st optical member and the 2 nd optical member can bend light from the object to be measured and guide the bent light to the corresponding lenses.

In the present embodiment, the 1 st optical unit and the 2 nd optical unit have the same optical system. By using the optical systems having the same structure, when measuring chromatic aberration at 2 sites, it is possible to measure chromatic aberration by removing the model dependency of measurement between the 1 st optical unit and the 2 nd optical unit. This enables measurement with high accuracy.

The minimum measurement width of the measurement range in the object to be measured of the optical unit of at least one of the 1 st optical unit and the 2 nd optical unit is less than 3mm. In general, the size of the USC unit is determined according to the size of a camera mounted on the device. For example, in many smartphones, the size (diameter) of the camera is around 3mm. Therefore, by making the minimum measurement width of the measurement range smaller than 3mm, the color and brightness of the USC portion on the display of the smart phone can be measured.

In the present embodiment, the measurement angle of the optical unit of at least one of the 1 st optical unit and the 2 nd optical unit is between ±15°. Preferably, the measurement angle of the optical unit of at least one of the 1 st optical unit and the 2 nd optical unit is between ±10°. The term "measuring angle" may also be replaced by "opening angle". According to this configuration, accurate measurement of color and brightness can be performed.

According to the present embodiment, each of the 1 st optical member and the 2 nd optical member is a prism, and the abbe number vd related to the D-line of the material of the prism satisfies vd > 40. When the abbe number vd is less than 40, the chromatic aberration generated by the prism portion becomes large, and therefore the deviation of the measurement range due to the wavelength becomes large. Therefore, the accuracy of measurement is lowered. By satisfying vd > 40, high-precision measurement can be performed. As a material having vd > 40, a commercially available material can be used. As an example, S-LAH65VS (vd=46.5) supplied from OHARA (zebra, inc.).

Preferably, vd > 50. The abbe number vd in one embodiment is exemplified by vd=55.4, though not particularly limited.

According to this embodiment, the prism has a thickness of greater than 10mm and the internal transmittance of the prism at a wavelength of 400nm is greater than 0.9.

The prism material has a tendency to have a lower transmittance at shorter wavelengths. Since the prism satisfying the above condition can ensure the light quantity at the time of measurement, the S/N ratio can be improved. Preferably, the prism has a thickness of greater than 10mm and the internal transmittance of the prism at a wavelength of 400nm is greater than 0.95. The "thickness" refers to a dimension corresponding to the height of the prism from the lowest surface (surface closest to the object to be measured) of the prism.

According to the present embodiment, if the refractive index of the prism is n, the optical path length of the principal ray passing through the prism is a, and the measurement distances of the 1 st photometry section and the 2 nd photometry section are WD0, a/(WD 0×n) < 0.9. A/(w0×n) represents the proportion of the light path in the prism in the light path before the light emitted from the object enters the 1 st photometry section (or the 2 nd photometry section). The greater the ratio, the smaller the distance between the object and the prism. In other words, the optical device needs to be brought closer to the object to be measured. When a/(w0×n) exceeds 0.9, the optical distance becomes short, and thus the usability of the optical apparatus decreases. The value of a/(w0×n) in one embodiment is 0.69, although not particularly limited.

According to the present embodiment, the refractive index Nd of each of the 1 st optical member and the 2 Nd optical member is 1.4 or more. According to this structure, the light can be bent by 90 ° by total reflection inside each of the 1 st optical member and the 2 nd optical member. Preferably, the refractive index Nd is 1.6 or more.

In an optical system having a large aperture and a large measurement angle, an upper ray (a ray inclined to a positive angle with respect to a principal ray) and the principal ray are incident on a reflection surface at different angles. In order to totally reflect light incident at a larger incident angle, the higher the refractive index of the optical member is, the better. Further, by transmitting light through the optical member made of a medium having a high refractive index, a larger working distance can be ensured. So that the refractive index Nd preferably satisfies the above condition.

In the present embodiment, the aperture of each of the 1 st lens and the 2 nd lens is larger than 2 times the distance between the center of the measurement range of the 1 st photometry section and the center of the measurement range of the 2 nd photometry section. According to this configuration, the approaching portion on the object to be measured can be measured while maintaining the brightness.

Further, as shown in fig. 1 and 2, according to the present embodiment, the color luminance meter and the color meter are provided with the above-described optical device. Thus, a color luminance meter and a color meter capable of measuring at an approaching portion while maintaining brightness can be realized.

Examples

The following describes various embodiments of the present invention.

Example 1

Fig. 5 is a diagram showing a structure of an optical device according to embodiment 1 of the present invention. As shown in fig. 5, the probe 10A includes a photometry section 12A (1 st photometry section) and an optical unit 11A (1 st optical unit). The probe 10B includes a photometry section 12B (2 nd photometry section), and an optical unit 11B (2 nd optical unit).

The photometry section 12A receives light from the 1 st part AR1 of the object 1. The photometry section 12B receives light from the 2 nd portion AR2 of the object 1. As shown in fig. 3, each photometry section has 3 sensors. In various embodiments, these 3 sensors are integrally represented as 1 sensor.

The optical unit 11A has a lens 22A (1 st lens) and a prism 21A (1 st optical element). The lens 22A is the lens closest to the object side, and condenses light from the 1 st portion AR1 of the object 1 onto the photometry section 12A. The prism 21A deflects the light from the 1 st portion AR1 of the object 1 to guide the light to the lens 22A.

The optical unit 11B has a lens 22B (2 nd lens) and a prism 21B (2 nd optical element). The lens 22B is the lens closest to the object side, and condenses light from the 2 nd portion AR2 of the object 1 on the photometry section 12B. The prism 21B deflects the light from the 2 nd portion AR2 of the object 1 and guides the light to the lens 22B. Fig. 5 shows only the lens closest to the object side of each optical unit.

The optical axis AX1 is an optical axis from the 1 st portion AR1 of the object 1 to the optical unit 11A of the lens 22A. The optical axis AX2 is an optical axis from the 2 nd portion AR2 of the object 1 to the optical unit 11B of the lens 22B. The portion of the optical axis AX1 from the 1 st portion AR1 of the object 1 to the prism 21A is parallel to the portion of the optical axis AX2 from the 2 nd portion AR2 of the object 1 to the prism 21B. The portion from the center of the lens 22A to the optical axis AX1 of the prism 21A and the portion from the center of the lens 22B to the optical axis AX2 of the prism 21B are also parallel.

The distance D represents the distance between the center of the 1 st part AR1 and the center of the 2 nd part AR 2. The interval D1 represents an interval between the optical axis AX1 and the optical axis AX 2. The interval D2 represents the distance between the center of the lens 22A and the center of the lens 22B. Between D, D and D2, the relationship of D2 > D1 holds. Thus, the interval D1 is smaller than the interval D2. Further, D2 > 2 XD. According to example 1, the color brightness of the approaching portion on the object to be measured can be measured while maintaining high optical performance.

In embodiment 1, each of the

prisms

21A,21B is a parallelepiped prism, and light from the object 1 to be measured is totally reflected 2 times and guided to the corresponding lens. Fig. 6A, 6B, and 6C are diagrams showing the shape of a parallelepiped prism according to embodiment 1 of the present invention. Fig. 6A is an oblique view of a parallelepiped prism according to embodiment 1 of the present invention, fig. 6B is a front view of the parallelepiped prism according to embodiment 1 of the present invention, and fig. 6C is a plan view of the parallelepiped prism according to embodiment 1 of the present invention.

The parallelepiped prism has faces 31 to 36. The surface 31 is an incident surface facing the object side. The face 32 is an exit face, parallel to the face 31, and directed towards the corresponding lens. The faces 33 and 34 are parallel to each other and each have a pair of parallelograms with a vertex angle of 45 °. The

surfaces

35 and 36 are reflective surfaces arranged in parallel and opposite to each other. The surface 35 is a first reflection surface that reflects light incident on the surface 31 (incident surface). Is the 2 nd reflecting surface for reflecting and guiding the light reflected by the surface 35 to the surface 32 (exit surface). In addition, the spacing between faces 31 and 32 corresponds to the "thickness" of the parallelepiped prism. "t" shown in fig. 6B represents the "thickness" of the parallelepiped prism.

The end of the parallelepiped prism connecting the incident surface (surface 31) and the first reflecting surface (surface 35) may be a chamfered end. Fig. 7 is a view showing a state in which 2 parallelepiped prisms are closely arranged. The smaller the interval between 2 parts of the object 1, the closer the

prisms

21A and 21B need to be. However, if the opposite ends 37 of the

prisms

21A and 21B are not chamfered, the ends 37 may contact each other as shown in fig. 7 (a). As shown in fig. 7 (B), by chamfering the opposite end portions 37, contact between the end portions 37 can be avoided. The

prisms

21A,21B can be brought closer to each other. Therefore, 2 portions close to each other on the object 1 can be measured.

The parameters related to example 1 are shown below.

(1) Probes 10A,10B

Probe manufactured by Konika Meida Co., ltd. (model CA-VP 402)

Working distance (distance from the bottom of prism to DUT (object to be measured): 7.2mm

Lens

22A,22B lens aperture: 24.5mm

Housing width (probe body width) W1, W2:47mm

Measurement diameters in 1 st and 2 nd portions AR1 and AR 2: 2mm of

Measurement angle (opening angle): 10 degree

(2)

Prisms

21A,21B

Size: 20 mm. Times.16.55 mm. Times.18 mm (see FIGS. 6A-6C)

Thickness: 11.703mm

Internal transmittance at wavelength 400 nm: 99% (when the transmission thickness is 10 mm)

Glass material: OHARA S-BSM18 (Nd: 1.638, vd: 55.38)

(3) Configuration of

Length of principal ray in prism a:51.9417mm

Measurement distance WD0 of probe: 28mm of

Distance D (center-to-center distance) between 1 st part AR1 and 2 nd part AR 2: 10mm of

Interval D2 between optical axes: 23.5mm

Example 2

Fig. 8 is a diagram showing a structure of an optical device according to embodiment 2 of the present invention. The structure shown in fig. 8 is basically the same as that of embodiment 1 shown in fig. 5, and therefore, a detailed description thereof will not be repeated. In addition to

lenses

22A and 22B, FIG. 8 also shows

lenses

26A and 26B. The number of lenses of each of the

optical units

11A and 11B is not particularly limited.

The same as in example 1 holds for the intervals D, D1, D2, the relationship of D2 > D1 and the relationship of D2 > 2×d. Thus, according to example 2, the color brightness of the approaching portion on the object to be measured can be measured while maintaining high optical performance.

As in embodiment 1, in embodiment 2, the

prisms

21A,21B are each parallelepiped prisms. In embodiment 1 and embodiment 2, the size of the prism 21A is different. The dimensions of the prism 21B are the same in embodiment 1 and embodiment 2. As in example 1, the portion of the optical axis AX1 from the 1 st portion AR1 of the object 1 to the prism 21A is parallel to the portion of the optical axis AX2 from the 2 nd portion AR2 of the object 1 to the prism 21B. The portion of the optical axis AX1 from the center of the lens 22A to the prism 21A and the portion of the optical axis AX2 from the center of the lens 22B to the prism 21B are also parallel.

Fig. 9A, 9B, and 9C are diagrams showing the shape of a parallelepiped prism according to embodiment 2 of the present invention. Fig. 9A is an oblique view of a parallelepiped prism according to embodiment 2 of the present invention, fig. 9B is a front view of a parallelepiped prism according to embodiment 2 of the present invention, and fig. 9C is a plan view of a parallelepiped prism according to embodiment 2 of the present invention. The surface 31 is an incident surface facing the object side, the surface 32 is an exit surface, and the

surfaces

35 and 36 are reflection surfaces. Each of the

faces

33 and 34 is a pair of parallelograms with a vertex angle of 45 °. The end of the parallelepiped prism connecting the incident surface (surface 31) and the first reflecting surface (surface 35) may be a chamfered end. "T" indicates the thickness of the prism.

The data relating to the optical device of example 2 are shown below.

(1) Probe with a probe tip

(1A) Probe 10A

Probe manufactured by Konika Meida Co., ltd. (model CA-VP 410)

Working distance (distance from the lowest surface of the prism to the object to be measured): 6mm of

Lens aperture of lens 22A: 23.7mm

Shell width (probe body width) W1:47mm

Measurement diameter in site 1 AR 1: 10mm of

Measurement angle (opening angle): + -8.5 DEG

(1B) Probe 10B

Probe manufactured by Konika Meida Co., ltd. (model CA-VP 402)

Working distance (distance from the lowest surface of the prism to the object to be measured): 7.2mm

Lens aperture of

lenses

22A, 22B: 24.5mm

Housing width (probe body width) W2:47mm

Measurement diameter in site 2 AR 2: 2mm of

Measurement angle (opening angle): 10 degree

(2)

Prisms

21A,21B

(2A) Prism 21A

Size: 25 mm. Times.25.5 mm. Times.18 mm (see FIGS. 9A-9C)

Prism thickness: 18.031mm

Internal transmittance at wavelength 400 nm: 92.4% (through thickness 10 mm)

Glass material: OHARA S-LAH60 (N d:1.834, vd:37.16)

(2B) Prism 21B

Size: 20 mm. Times.16.55 mm. Times.18 mm (see FIGS. 6A-6C)

Thickness: 11.703mm

Glass material: OHARA S-BSM18 (N D:1.638, v D: 55.38)

(3) Configuration of

Length a of principal ray through prism:

78.862mm (prism 21A), 51.9417mm (prism 21B)

Measurement distance WD0 of probe:

30mm (probe 10A), 28mm (probe 10B)

Interval D2 between optical axes: 23.5mm

Example 3

Fig. 10 is a diagram showing a structure of an optical device according to embodiment 3 of the present invention. In the structure shown in fig. 10, the structure of the

probes

10A and 10B is basically the same as that of embodiment 1 shown in fig. 5, and therefore, detailed description thereof will not be repeated. In embodiment 3, each of the

prisms

21A,21B is a triangular prism, and light from the object 1 to be measured is totally reflected 1 time and guided to each of the

lenses

22A, 22B. The relationship of D2 > D1 and D2 > 2×d holds for the intervals D, D, D2. According to example 3, the color brightness of the approaching portion on the object to be measured can be measured while maintaining high optical performance.

Fig. 11A,11B, and 11C are diagrams showing the shape of a triangular prism according to embodiment 3 of the present invention. Fig. 11A is an oblique view of a triple prism according to embodiment 3 of the present invention, fig. 11B is a front view of a triple prism according to embodiment 3 of the present invention, and fig. 11C is a side view of a triple prism according to embodiment 3 of the present invention. The triangular prism has faces 31A to 35A. The surface 31A is an incident surface facing the object side, and the surface 32A is an outgoing surface facing the corresponding lens. The surface 33A is a reflecting surface that reflects light incident on the surface 31A (incident surface). The

surfaces

33A and 34A are arranged parallel to each other. Each of the

faces

34A and 35A is in the shape of an equilateral triangle. The height from the face 31A to the apex of the regular triangle (faces 34A, 35A) corresponds to the "thickness" of the triangular prism. "t" in fig. 11B indicates the thickness of the prism. As in examples 1 and 2, the portion of the optical axis AX1 from the 1 st part AR1 of the object 1 to the prism 21A is parallel to the portion of the optical axis AX2 from the 2 nd part AR2 of the object 1 to the prism 21B.

The parameters related to example 3 are shown below.

(1) Probes 10A,10B

Probe manufactured by Konika Meida Co., ltd. (model CA-VP 402)

Working distance (distance from the lowest surface of the prism to the object to be measured): 7.7mm

Lens aperture of

lenses

22A, 22B: 24.5mm

Housing width (probe body width) W1, W2:47mm

Measurement diameters in 1 st and 2 nd portions AR1 and AR 2: 2mm of

Measurement angle (opening angle): 10 degree

(2)

Prisms

21A,21B

Size: 25 mm. Times.25 mm (refer to FIGS. 11A to 11C)

Thickness: 21.651mm

Internal transmittance at wavelength 400 nm: 99.6% (when the transmission thickness is 10 mm)

Glass material: OHARA S-FPL55 (N d:1.438, vd: 94.66)

(3) Configuration of

Length a of principal ray through prism: 31.1496mm

Measurement distance WD0 of probe: 28mm of

Distance between optical axes (distance between centers of

lenses

22A, 22B) D2:50.0mm

While the embodiments and examples of the present invention have been described, the embodiments disclosed herein are to be considered in all respects as illustrative and not restrictive. The scope of the invention is indicated by the appended claims, and all changes that come within the meaning and range of equivalency of the claims are intended to be embraced therein.

Description of the reference numerals

1 object to be measured, 2 displays, 3 st part, 4 nd part, 10A,10B probes, 11A,11B optical units, 12A,12B photometry parts, 13A,13B signal processing parts, 14A,14B calculation parts, 21A,21B optical parts (prisms), 22A,22B,26A,26B lenses, 23A,23B beam splitting parts, 24A-1 to 24A-3, 24B-1 to 24B-3 filters, 25A-1 to 25A-3, 25B-1 to 25B-3 sensors, 31A, 32A, 33A, 34A, 35A,36 faces, 37 end (prism), 40 illumination section, 50 control processing section, 51 control section, 52 display section, 53 operation section, 54 storage section, 101 colorimeter, 102 colorimeter, A1, A2 minimum measurement width, AR1 st part, AR2 nd part, AX1, AX2 optical axis, D1, D2 interval.

Claims

1. An optical device is provided with:

a1 st photometry section for receiving light from the 1 st part of the object to be measured;

a1 st optical unit including a1 st lens for condensing light from the 1 st part on an object side of the 1 st photometry section, and a1 st optical member for deflecting and guiding the light from the 1 st part to the 1 st lens;

a2 nd photometry section for receiving light from a2 nd part of the object to be measured; and

a2 nd optical unit including a2 nd lens for condensing light from the 2 nd portion on an object side of the 2 nd photometry section, and a2 nd optical member for deflecting and guiding the light from the 2 nd portion to the 2 nd lens,

an optical axis of the 1 st optical unit from the object to the 1 st optical member is substantially parallel to an optical axis of the 2 nd optical unit from the object to the 2 nd optical member, and a distance between the optical axis of the 1 st optical unit and the optical axis of the 2 nd optical unit is smaller than a distance between a center of the 1 st lens and a center of the 2 nd lens.

2. The optical device of claim 1, wherein,

the 1 st optical member and the 2 nd optical member reflect light from the object to be measured and guide the reflected light to the 1 st lens and the 2 nd lens, respectively.

3. The optical device of claim 2, wherein,

the 1 st optical member totally reflects the light from the object to be measured 2 times and guides the light from the object to be measured to the 1 st lens,

the 2 nd optical member totally reflects the light from the object to be measured 2 times and guides the light from the object to be measured to the 2 nd lens.

4. The optical device according to claim 3, wherein,

the 1 st optical component and the 2 nd optical component each have:

an incident surface facing the object side;

an exit surface facing a corresponding one of the 1 st lens and the 2 nd lens;

a1 st reflection surface for reflecting light incident on the incidence surface; and

a2 nd reflecting surface for reflecting the light reflected by the 1 st reflecting surface and guiding the light to the emergent surface,

the entrance face and the exit face are substantially parallel,

the 1 st reflecting surface and the 2 nd reflecting surface are substantially parallel.

5. The optical device of claim 4, wherein,

the 1 st optical component and the 2 nd optical component are each a parallelepiped prism,

the end of the parallelepiped prism connecting the incident surface of the parallelepiped prism and the 1 st reflection surface is a chamfered end.

6. The optical device according to claim 1 or claim 2, wherein,

the 1 st optical member totally reflects the light from the object to be measured 1 time and guides the light from the object to be measured to the 1 st lens,

the 2 nd optical member totally reflects the light from the object to be measured 1 time and guides the light from the object to be measured to the 2 nd lens.

7. The optical device of claim 6, wherein,

the 1 st optical member and the 2 nd optical member are each a triangular prism, and have:

an incident surface facing the object side;

an exit surface facing a corresponding one of the 1 st lens and the 2 nd lens; and

and a2 nd reflecting surface for totally reflecting the light incident on the incident surface and guiding the light to the emergent surface.

8. The optical device according to any one of claim 1 to claim 7, wherein,

the 1 st optical unit and the 2 nd optical unit have the same optical system.

9. The optical device according to any one of claim 1 to claim 8, wherein,

the minimum measurement width of the measurement range in the object to be measured of the optical unit of at least one of the 1 st optical unit and the 2 nd optical unit is less than 3mm.

10. The optical device according to any one of claim 1 to claim 9, wherein,

the measurement angle of the optical unit of at least one of the 1 st optical unit and the 2 nd optical unit is between ±15°.

11. The optical device according to any one of claim 1 to claim 7, wherein,

the 1 st optical component and the 2 nd optical component are prisms respectively,

the Abbe number vd of the prism relative to the D line of the material satisfies vd > 40.

12. The optical device of claim 11, wherein,

the prisms have a thickness of greater than 10mm,

the prism has an internal transmittance at a wavelength of 400nm of greater than 0.9.

13. The optical device according to claim 11 or claim 12, wherein,

if the refractive index of the prism is set to n,

let the optical path length of the chief ray passing through the inside of the prism be a,

the measurement distance of the 1 st photometry section and the 2 nd photometry section is WD0,

a/(w0×n) < 0.9 is satisfied.

14. The optical device according to any one of claim 1 to claim 13, wherein,

the refractive index Nd of each of the 1 st optical member and the 2 Nd optical member is 1.4 or more.

15. The optical device according to any one of claim 1 to claim 14, wherein,

the aperture of each of the 1 st lens and the 2 nd lens is larger than 2 times the distance between the center of the metering range of the 1 st photometry section and the center of the metering range of the 2 nd photometry section.

16. A colour luminance meter provided with an optical device according to any one of claims 1 to 15.

17. A colorimeter provided with an optical device according to any one of claims 1 to 15.