CN107870037B

CN107870037B - Spectrometry device

Info

Publication number: CN107870037B
Application number: CN201710640422.9A
Authority: CN
Inventors: 白岩久志
Original assignee: Otsuka Electronics Co Ltd
Current assignee: Otsuka Electronics Co Ltd
Priority date: 2016-09-23
Filing date: 2017-07-31
Publication date: 2021-06-29
Anticipated expiration: 2037-07-31
Also published as: JP6833426B2; TW201814362A; JP2018048980A; KR20180033054A; CN107870037A; TWI728177B; KR102355342B1

Abstract

The invention provides a spectroscopic measurement apparatus capable of reducing measurement errors caused by bending of an optical fiber and improving the amount of light supplied to a spectroscopic measurement unit. The spectrometry device is provided with: a spectroscopic measurement unit for performing spectroscopic measurement of light incident through the slit; and a light diffusion means for diffusing light supplied from the plurality of optical fibers and physically fixing the diffused light to the slit so that the light is incident on the slit directly or via a lens or a mirror.

Description

Spectrometry device

Technical Field

The present invention relates to a spectroscopic measurement apparatus.

Background

Patent document 1 discloses the following: in order to solve this problem, an integrating sphere is used as an optical fiber coupler for optically coupling a plurality of optical fibers, and a measurement error may occur due to a change in the light distribution of light emitted from the optical fiber caused by bending of the optical fiber.

Documents of the prior art

Patent document

Patent document 1: japanese patent No. 5643983

Disclosure of Invention

Problems to be solved by the invention

In patent document 1, light from a light source is guided to an integrating sphere through an incident side optical fiber, and light emitted from the integrating sphere is guided to a spectroscopic measuring instrument through an exit side optical fiber. Therefore, even if the measurement error caused by the bending of the incident-side optical fiber can be reduced, the measurement error caused by the bending of the exit-side optical fiber cannot be reduced.

Further, since the light guided to the integrating sphere by the plurality of incident side optical fibers is guided from the integrating sphere to the spectroscopic measuring device by one exit side optical fiber, there is a possibility that a sufficient amount of light cannot be obtained in the spectroscopic measuring device.

The present invention has been made in view of the above problems, and an object thereof is to provide a spectroscopic measurement apparatus capable of reducing measurement errors caused by bending of an optical fiber and increasing the amount of light supplied to a spectroscopic measurement unit.

Means for solving the problems

In order to solve the above problem, a spectroscopic measurement apparatus according to the present invention includes: a spectroscopic measurement unit for performing spectroscopic measurement of light incident through the slit; and a light diffusion means for diffusing light supplied from the plurality of optical fibers and physically fixing the diffused light to the slit so that the light is incident on the slit directly or via a lens or a mirror.

The spectrometry device may further include an aperture that restricts a light flux of the diffused light toward the slit. The spectrometry device may further include the plurality of optical fibers that supply light to the light diffusion unit. The light diffusion means may include an emission portion that emits the diffused light, and the slit may face the emission portion.

In one aspect of the present invention, it may be: the light diffusion means is a diffusion plate, light supplied from the plurality of optical fibers is incident on one surface of the diffusion plate, and the diffused light is emitted from the other surface of the diffusion plate.

Further, the exit ends of the plurality of optical fibers may be arranged in a manner offset from the optical axis passing through the slit. Further, the exit ends of the plurality of optical fibers may emit light from a position offset from the optical axis passing through the slit in a direction toward the slit. Further, the exit ends of the plurality of optical fibers may be configured to surround an optical axis passing through the slit.

In one aspect of the present invention, the light diffusion unit may be an integrating sphere that diffusely reflects the light supplied from the plurality of optical fibers on an inner wall surface of a sphere and allows the diffused light to exit from a detection window. In the present invention, the term "integrating sphere" is used in the following sense: devices that diffuse incident light on spherical inner wall surfaces, such as a perfect sphere, a hemisphere, and an 1/8 sphere, are widely included.

In one aspect of the present invention, the spectrometry device may further include a light shielding switching unit that supplies light from a selected one of the plurality of optical fibers to the light diffusion unit and blocks light from the remaining optical fibers.

Further, it may be: the light shielding switching means includes a direction conversion means for converting the direction of the light from the part of the optical fibers so that the light from the part of the optical fibers is incident on the light diffusion means from the optical axis passing through the slit.

Effects of the invention

According to the present invention, since the light diffusion means is physically fixed to the slit so that the diffused light is incident on the slit directly or via a lens or a mirror, it is possible to reduce the measurement error caused by the bending of the optical fiber and to increase the amount of light supplied to the spectroscopic measurement unit.

Drawings

Fig. 1 is a schematic diagram showing an example of the configuration of a spectrometry device according to a first embodiment of the present invention.

Fig. 2A is a schematic diagram showing a configuration example of the optical fiber coupling section.

Fig. 2B is a schematic diagram showing a configuration example of the optical fiber coupling section.

Fig. 3 is a schematic diagram showing an example of the configuration of a spectrometry device according to a second embodiment of the present invention.

Fig. 4 is a schematic diagram showing an example of the configuration of a spectrometry device according to a third embodiment of the present invention.

Fig. 5 is a schematic diagram showing an example of the configuration of a spectrometry device according to a fourth embodiment of the present invention.

Fig. 6A is a schematic diagram showing a configuration example of the optical fiber switching unit.

Fig. 6B is a schematic diagram showing a configuration example of the optical fiber switching unit.

Fig. 7A is a schematic diagram showing a modification of the optical fiber switching section.

Fig. 7B is a schematic diagram showing a modification of the optical fiber switching section.

Fig. 8 is a schematic diagram showing a first application example of the spectroscopic measurement apparatus according to the embodiment of the present invention.

Fig. 9 is a schematic diagram showing a second application example of the spectroscopic measurement apparatus according to the embodiment of the present invention.

Fig. 10 is a schematic diagram showing a reference example.

Fig. 11 is a schematic diagram showing a third application example of the spectrometry device according to the embodiment of the present invention.

Fig. 12 is a schematic diagram showing a fourth application example of the spectrometry device according to the embodiment of the present invention.

Description of reference numerals:

1 spectroscopic measuring apparatus

2 casing

3 spectroscopic measurement unit

32 diffraction grating

34 linear sensor

4 slit plate

4a slit

5 optical fiber coupling part

52 diffusion plate (one example of light diffusion unit)

61. 63 condenser lens

65 diaphragm

67 light gathering reflector

7 integrating sphere (an example of light diffusion means)

714 inner wall surface

73a detecting window

8 optical fiber switching part

82. 84 shading switching board (one example of shading switching unit)

86. 87 reflector (Direction changing unit)

91. 92 optical fiber

913. 923 exit end

100 dual beam assay system

200 reflected light measurement system

300 transmission light measuring system

LA optical axis

Detailed Description

Embodiments of the present invention will be described with reference to the accompanying drawings. In the following description, the same reference numerals are used for the overlapping components, and detailed description thereof may be omitted.

(first embodiment)

Fig. 1 is a schematic diagram showing a configuration example of a spectrometry device 1A according to a first embodiment of the present invention. Fig. 2A and 2B are schematic diagrams showing an example of the configuration of the optical fiber coupling section 5A. The spectrometry device 1A includes a spectrometry unit 3 and an optical fiber coupling unit 5A.

The spectroscopic measurement unit 3 performs spectroscopic measurement of light incident through the slit 4a formed in the slit plate 4. The spectroscopic measurement unit 3 includes a diffraction grating 32 that diffracts the light incident from the slit 4a and a line sensor 34 that receives the light diffracted by the diffraction grating 32, and detects the spectrum of the incident light. The length (height) of the slit 4a corresponds to the lengths of the diffraction grating 32 and the linear sensor 34.

As the spectroscopic measurement unit 3, various known configurations capable of spectroscopic measurement can be applied. Although concave diffraction gratings (concave gratings) are applied in the illustrated example, the present invention is not limited to this, and a Turner-mirror spectrometer (Czerny-turning spectrometer) or a Transmission spectrometer (Transmission spectrometer) may be applied, for example. Although a linear sensor (Multi sensor) is applied in the illustrated example, the present invention is not limited to this, and a method of detecting a spectrum by rotating a diffraction grating using a Single sensor (Single sensor), for example, may be applied.

Based on the spectrum detected by the spectroscopic measurement unit 3: evaluation of characteristics as a light source such as chromaticity, illuminance, luminance, and color rendering property; measurement of optical characteristics of an object to be measured such as surface characteristics, reflection characteristics, and transmission (absorption) characteristics; and measurement of physical properties of a measurement object such as film thickness.

The optical fiber coupling section 5A optically couples the plurality of

optical fibers

91 and 92. The optical fiber coupling section 5A includes a diffusion plate 52, a condenser lens 61, and an aperture 65, and couples light supplied from the plurality of

optical fibers

91 and 92 and guides the coupled light to the slit 4 a.

The casing 2 of the spectrometry device 1 includes a first housing portion 21 that houses the spectrometry unit 3 and a second housing portion 23 that is provided with the optical fiber coupling unit 5A. The second accommodating portion 23 accommodates the diffusion plate 52, the condenser lens 61, and the diaphragm 65. To prevent stray light, the first accommodation portion 21 and the second accommodation portion 23 may be separated by the slit plate 4.

The

optical fibers

91 and 92 propagate light incident from the incident ends 911 and 921 and emit the light from the emission ends 913 and 923. The

optical fibers

91 and 92 are, for example, bundles of optical fibers in which a plurality of optical fiber wires are bundled. The emission ends 913 and 923 are introduced into the second housing section 23 that houses the optical fiber coupling section 5A. The emission ends 913 and 923 may be detachable from the second accommodation section 23.

The diffusion plate 52 is an example of a light diffusion means, and is a plate-shaped light transmitting member having fine protrusions on the surface, such as ground glass. The diffusion plate 52 is not limited, and a light diffusion film may be applied. The diffusion plate 52 diffuses the light supplied from the plurality of

optical fibers

91, 92. Even if the light supplied from the

optical fibers

91 and 92 is polarized, the light is diffused by the diffusion plate 52 to eliminate the polarization.

The diffusion plate 52 is disposed between the emission ends 913 and 923 of the plurality of

optical fibers

91 and 92 and the slit 4 a. One surface of the diffusion plate 52 faces the emission ends 913 and 923, and the other surface of the diffusion plate 52 faces the slit 4 a. When the light emitted from the emission ends 913, 923 enters one surface of the diffusion plate 52, the diffused light is emitted from the other surface of the diffusion plate 52.

The condenser lens 61 is disposed between the diffusion plate 52 and the slit 4a, and condenses the diffused light emitted from the diffusion plate 52 toward the slit 4 a. The condenser lens 61 is configured to focus on the slit 4 a. The aperture (opening) 65 is disposed between the condenser lens 61 and the slit 4a, and restricts a light flux (light beam) of the diffused light toward the slit 4 a. The condenser lens 61 and the diaphragm 65 are not necessarily provided. Further, the diaphragm 65 may be provided inside the first housing portion 21.

The diffusion plate 52 is physically fixed to the slit 4a so that the diffused light emitted from the diffusion plate 52 enters the slit 4a via the condenser lens 61. That is, the light emitted from the diffusion plate 52 is directly incident on the condenser lens 61, and the light emitted from the condenser lens 61 is directly incident on the slit 4 a. In this way, in the present embodiment, the light emitted from the diffusion plate 52 enters the slit 4a without passing through the optical fiber.

The light collecting lens 61 is not limited to this, and the diffused light emitted from the diffusion plate 52 may be directly incident on the slit 4 a.

Since the light from the

optical fibers

91 and 92 is coupled by the diffusion plate 52 in this manner, there is no problem in coupling the light even if the types (the Number of Apertures (NA) and the diameter of the element wire) of the

optical fibers

91 and 92 are different from each other. For example, the optical fiber 91 may be an SMA optical fiber (NA 0.21, plain wire diameter 0.5mm), and the optical fiber 92 may be an FC optical fiber (NA 0.11, plain wire diameter 0.2 mm). Further, since the light from the

optical fibers

91 and 92 is diffused by the diffusion plate 52 and enters the slit 4a, even if the positions of the emission ends 913 and 923 of the

optical fibers

91 and 92 are slightly shifted, the influence of the wavelength shift and the like of the spectroscopic measurement unit 3 is small. Therefore, the range of position adjustment of the emission ends 913 and 923 of the

optical fibers

91 and 92 is larger than that of a spectroscopic measurement apparatus not including the light diffusion means.

The slit plate 4 and the diffusion plate 52 are fixed to the housing 2. Specifically, the slit plate 4 is fixed to the boundary between the first housing portion 21 and the second housing portion 23 of the housing 2 or the vicinity thereof. The diffusion plate 52 is fixed inside the second housing portion 23 so as to divide the inside of the second housing portion 23 into a space on the

optical fibers

91 and 92 side and a space on the slit 4a side. In order to prevent stray light, it is preferable that the two spaces are completely separated by the diffusion plate 52 and a member supporting the peripheral edge portion thereof.

The diffusion plate 52 may be fixed by being inserted into a guide groove provided in the inner wall of the second housing portion 23, or may be fixed to a protrusion provided in the inner wall of the second housing portion 23 by a screw, an adhesive, or the like, for example. The fixing method of the diffusion plate 52 is not particularly limited.

Fig. 2A is a view when the optical fiber coupling section 5A is viewed from the side with respect to the optical axis LA passing through the slit 4a, and fig. 2B is a view when the diffusion plate 52 is viewed from the slit 4a side. The optical axis LA passing through the slit 4a is a virtual axis representing the light flux emitted from the diffusion plate 52 and passing through the slit 4a, and is an axis passing through the center of the condenser lens 61 and the center of the diaphragm 65.

The emission ends 913 to 953 of the optical fibers 91 to 95 are disposed so as to be offset from the optical axis LA passing through the slit 4 a. That is, the emission ends 913 to 953 are not on the optical axis LA, but are spaced outward (radially) from the optical axis LA. When a specific exit end is located on the optical axis LA, light from this exit end passes through the slit 4a more easily than light from the remaining exit ends, and there is a fear that coupling of light may be uneven. Therefore, all the emission ends 913 to 953 are arranged to be offset from the optical axis LA, and thus the coupling of light can be made uniform.

Furthermore, the exit ends 913 to 953 of the plurality of optical fibers 91 to 95 are arranged to surround the optical axis LA passing through the slit 4 a. Here, the arrangement around the optical axis LA also includes the arrangement sandwiching the optical axis LA when the number of the emission ends is two. The emission ends 913 to 953 are preferably arranged at the same distance from the optical axis LA, and are more preferably arranged so as to be rotationally symmetrical about the optical axis LA. This makes it possible to further uniformize the coupling of light.

The light-emitting ends 913 to 953 of the optical fibers 91 to 95 emit light in a direction toward the slit 4a from positions deviated from the optical axis LA passing through the slit 4 a. That is, the light emitted from the emission ends 913 to 953 is not parallel to the optical axis LA, but is emitted in a direction inclined to the side closer to the optical axis LA than the light. Thus, even if the emission ends 913 to 953 are deviated from the optical axis LA, the amount of light passing through the slit 4a can be further increased.

When the purpose is to eliminate polarization, it is preferable to use a diffusion plate having a strong polarization eliminating function as the diffusion plate 52. When the amount of light supplied to the spectroscopic measurement unit 3 is to be increased, a diffusion plate having a high transmittance is preferably used. In this way, the type of the diffusion plate 52 can be selected according to the purpose and use of the measurement.

In the first embodiment described above, the diffusion plate 52 is physically fixed to the slit 4a such that the diffused light emitted from the diffusion plate 52 enters the slit 4a directly or via the condenser lens 61. Thus, since the output side optical fiber as in patent document 1 does not exist, it is possible to reduce the measurement error caused by the bending of the optical fiber.

Further, the amount of light supplied to the spectroscopic measurement unit 3 can be increased. In the configuration in which light is guided to the spectrometer through the output-side optical fiber as in patent document 1, the amount of light supplied to the spectrometer may be insufficient. For example, when the exit-side optical fiber includes a plurality of optical fiber strands, the exit ends of the plurality of optical fiber strands are aligned and fixed along the slit. In this case, the number and the diameter of the optical fiber are limited by the length of the slit, and thus the amount of light supplied to the slit may be insufficient. In contrast, in the present embodiment, if a sufficient amount of light is supplied from the

optical fibers

91 and 92 to the diffusion plate 52, the diffused light enters the slit 4a directly or via the condenser lens 61, and therefore, even if there is a slight loss in the amount of light at the diffusion plate 52, a sufficient amount of light can be supplied to the spectroscopic measurement unit 3 (which will be described in detail later with reference to fig. 8 to 10).

(second embodiment)

Fig. 3 is a schematic diagram showing an example of the configuration of a spectrometry device 1B according to a second embodiment of the present invention. The optical fiber coupling section 5B included in the spectrometry device 1B includes an integrating sphere 7, a collimator lens 62, a condenser lens 63, and an aperture 65.

The integrating sphere 7 is an example of light diffusion means, and diffuses light supplied from the plurality of

optical fibers

91 and 92 on the spherical inner wall surface 714, and emits the diffused light from the detection window 73 a. Specifically, integrating sphere 7 is composed of hemispherical shell 71 and circular flat plate 73, and has a hollow hemispherical inner space. Inner wall surface 714 of hemispherical shell 71 is a white highly diffuse reflection surface formed of barium sulfate, PTFE (polytetrafluoroethylene) sintered product, or the like, and inner wall surface 734 of circular flat plate portion 73 is a mirror formed of aluminum vapor deposition or the like.

The hemispherical shell portion 71 of the integrating sphere 7 is provided with a plurality of

fitting portions

711 and 712 to which the emission ends 913 and 923 of the

optical fibers

91 and 92 are fitted. The emission ends 913 and 923 may be detachable from the

attachment portions

711 and 712. Integrating sphere 7 couples the light supplied from the plurality of

optical fibers

91 and 92 by diffusing the light supplied from the plurality of

optical fibers

91 and 92 in the internal space thereof. Even if the light supplied from the

optical fibers

91 and 92 is polarized, the light is diffused in the internal space of the integrating sphere 7, thereby eliminating the polarization.

A detection window 73a for outputting light diffused in the internal space of integrating sphere 7 to the outside is provided in the center of circular flat plate portion 73. The detection window 73a is an emission portion from which diffused light is emitted, and faces the slit 4 a. Further, a light shielding plate 75 for preventing the light emitted from the emission ends 913 and 923 from directly entering the detection window 73a is provided around the detection window 73 a.

In the present embodiment, integrating sphere 7 is a hemisphere, but is not limited to this, and may be a perfect sphere or an 1/8 sphere.

The collimator lens 62 is disposed between the integrating sphere 7 and the slit 4a, and converts light emitted from the detection window 73a of the integrating sphere 7 into parallel light. The condenser lens 63 is disposed between the collimator lens 62 and the slit 4a, and condenses the light emitted from the collimator lens 62 toward the slit 4 a. The condenser lens 63 is configured to focus on the slit 4 a. The collimator lens 62, the condenser lens 63, and the diaphragm 65 are not necessarily provided. Further, the diaphragm 65 may be provided inside the first housing portion 21.

The integrating sphere 7 is physically fixed to the slit 4a so that the diffused light emitted from the detection window 73a enters the slit 4a via the collimator lens 62 and the condenser lens 63. That is, the light emitted from the detection window 73a directly enters the collimator lens 62, the light emitted from the collimator lens 62 directly enters the condenser lens 63, and the light emitted from the condenser lens 63 directly enters the slit 4 a. In this way, in the present embodiment, the light emitted from the detection window 73a is not incident on the slit 4a via the optical fiber.

The collimator lens 62 and the condenser lens 63 may be omitted, and the diffused light emitted from the detection window 73a may be directly incident on the slit 4 a.

Integrating sphere 7 is fitted to second accommodating portion 23 of case 2. Specifically, the second housing portion 23 has an opening facing the protruding direction, and the integrating sphere 7 is attached so as to close the opening of the second housing portion 23. In order to prevent stray light, integrating sphere 7 preferably completely blocks the opening of second housing portion 23. Integrating sphere 7 is fixed to second housing portion 23 by a fastener such as a bolt. The fixing method of the integrating sphere 7 is not particularly limited.

According to the second embodiment described above, as in the first embodiment, the amount of light supplied to the spectroscopic measurement unit 3 can be increased while reducing the measurement error caused by the bending of the optical fiber.

(third embodiment)

Fig. 4 is a schematic diagram showing an example of the configuration of a spectrometry device 1C according to a third embodiment of the present invention. The optical fiber coupling section 5C included in the spectroscopic measurement apparatus 1C includes the diffusion plate 52, the light collection mirror 67, and the aperture 65.

The light collecting mirror 67 is disposed between the diffusion plate 52 and the slit 4a, and collects the diffused light emitted from the diffusion plate 52 toward the slit 4a while reflecting the diffused light. The light condensing mirror 67 is configured to perform focusing on the slit 4 a. The aperture (aperture) 65 is disposed between the light condensing mirror 67 and the slit 4a, and restricts a light flux (light beam) of the diffused light toward the slit 4 a. The light condensing mirror 67 is not limited thereto, and a plane mirror may be provided. Further, the diaphragm 65 may be provided inside the first housing portion 21.

The diffusion plate 52 is physically fixed to the slit 4a so that the diffused light emitted from the diffusion plate 52 enters the slit 4a via the light condensing mirror 67. That is, the light emitted from the diffusion plate 52 directly enters the light condensing mirror 67, and the light reflected from the light condensing mirror 67 directly enters the slit 4 a. In this way, in the present embodiment, the light emitted from the diffusion plate 52 is not incident on the slit 4a via the optical fiber.

According to the third embodiment described above, as in the first and second embodiments, the amount of light supplied to the spectroscopic measurement unit 3 can be increased while reducing the measurement error caused by the bending of the optical fiber. In addition, since the light condensing mirror 67 is used in the third embodiment, the chromatic aberration is smaller and the influence of the wavelength shift or the like of the spectroscopic measurement unit 3 is smaller than that in the case of using a lens.

In the third embodiment, the condenser lens 61 of the first embodiment is replaced with a condenser mirror 67, but the collimator lens 62 of the second embodiment may be replaced with a collimator mirror, and the condenser lens 63 may be replaced with a condenser mirror, in the same manner as described above.

(fourth embodiment)

Fig. 5 is a schematic diagram showing an example of the configuration of the spectrometry device 10 according to the fourth embodiment of the present invention. Fig. 6A and 6B are schematic diagrams showing a configuration example of the optical fiber switching unit 8. The spectrometry device 10 includes a spectrometry unit 3 and an optical fiber switching unit 8. The optical fiber switching section 8 selectively guides the light supplied from the plurality of optical fibers 91 to 95 to the slit 4 a.

The optical fiber switching section 8 is provided with a light shielding switching plate 82 in the optical fiber coupling section 5A of the first embodiment. That is, the optical fiber switching unit 8 includes the light shielding switching plate 82, the diffusion plate 52, the condenser lens 61, and the aperture 65. The light-shielding switching plate 82 is disposed between the light-emitting ends 913 to 953 of the optical fibers 91 to 95 and the diffusion plate 52. The optical fiber switching unit 8 may further include a light shielding switching plate 82 in the optical fiber coupling unit 5C according to the third embodiment.

The light-shielding switching plate 82 is an example of light-shielding switching means, and supplies light from a part (one in the illustrated example) of the optical fibers 91 to 95 selected from the plurality of optical fibers to the diffusion plate 52 through the opening 8a, and shields light from the remaining optical fibers. The light supplied to the diffusion plate 52 is diffused by the diffusion plate 52, and the diffused light is incident on the slit 4a via the condenser lens 61, as in the first embodiment.

Specifically, as shown in fig. 6B, the light-shielding switching plate 82 is formed with an opening 8a corresponding to one of the emission ends 913 to 953 of the plurality of optical fibers 91 to 95. Only light emitted from one of the emission ends 913 to 953 is supplied to the diffusion plate 52 through the opening 8a of the light-shielding switching plate 82, while light emitted from the remaining emission ends is blocked by the light-shielding switching plate 82 and is not supplied to the diffusion plate 52.

The light shielding switching plate 82 is configured to be movable or rotatable so that the plurality of emission ends 913 to 953 sequentially face the opening 8 a. Specifically, the light-shielding switching plate 82 is configured to be rotatable about the optical axis LA passing through the slit 4a, and the aperture 8a is configured to be movable on a circle about the optical axis LA. Thus, the opening 8a faces any one of the emission ends 913 to 953 according to the rotation angle of the light shielding switching plate 82. The spectrometry apparatus 10 may include an actuator, not shown, for example, for rotationally driving the light shielding switching plate 82 in response to a switching command.

The light shielding switching plate 82 may be configured to be movable between a light shielding position located between the emission ends 913 to 953 and the diffusion plate 52 and a retracted position away from the light shielding position. Thus, in the spectroscopic measurement apparatus 10, both functions of the optical fiber coupling unit 5 and the optical fiber switching unit 8 can be utilized.

The spectrometry apparatus 1B according to the second embodiment may be provided with a light shielding switching means for supplying light from a part of the optical fibers selected from the plurality of

optical fibers

91 and 92 to the integrating sphere 7 and shielding light from the remaining optical fibers.

According to the fourth embodiment described above, even when the light supplied from the plurality of optical fibers 91 to 95 is selectively guided to the slit 4a, the amount of light supplied to the spectroscopic measurement unit 3 can be increased while reducing the measurement error caused by the bending of the optical fiber, as in the first, second, and third embodiments.

Fig. 7A and 7B are schematic diagrams showing modifications of the optical fiber switching unit 8. Fig. 7A is a sectional view of the light-shielding switching plate 84 cut so as to pass through the optical axis LA passing through the slit 4a and the opening 8B, and fig. 7B is a view of the light-shielding switching plate 84 viewed from the slit 4a side.

The light-shielding switching plate 84 includes, as direction conversion means, mirrors 86 and 87, and the

mirrors

86 and 87 convert the direction of light from a part (one in the illustrated example) of the optical fibers selected from the plurality of optical fibers 91 to 98 so that the light from the part enters the diffusion plate 52 from the optical axis LA passing through the slit 4 a.

Specifically, an opening 8b corresponding to one of the emission ends 913 to 953 of the plurality of optical fibers 91 to 95 is formed in the surface of the light shielding switching plate 84 on the emission ends 913 to 983 side. On the other hand, an opening 8c is formed in the optical axis LA passing through the slit 4a on the surface of the light shielding switching plate 84 on the slit 4a side. A passage 8d connecting the

openings

8b and 8c is formed inside the light-shielding switching plate 84, and the

mirrors

86 and 87 are disposed in the passage 8 d.

Only light emitted from one of the emission ends 913 to 983 of the plurality of optical fibers 91 to 98, which is opposite to the opening 8b, enters the passage 8d from the opening 8b, is switched in direction by the

mirrors

86 and 87, is emitted from the opening 8c onto the optical axis LA, and is supplied to the diffusion plate 52. On the other hand, the light emitted from the remaining emission end is blocked by the light-shielding switching plate 84 and is not supplied to the diffusion plate 52.

The light shielding switching plate 84 is configured to be rotatable about an optical axis LA passing through the slit 4a, and the opening 8b is configured to face any one of the emission ends 913 to 983 while moving on a circumference about the optical axis LA. On the other hand, since the opening 8c is formed on the optical axis LA, even if light enters the opening 8b from any of the emission ends 913 to 918, the opening 8c emits light onto the optical axis LA.

The emission ends 913 to 983 of the optical fibers 91 to 98 are arranged to be offset from the optical axis LA passing through the slit 4a, and emit light parallel to the optical axis LA. A collimator lens 89 is disposed in front of the emission ends 913 to 983, and the light emitted from the emission ends 913 to 983 passes through the collimator lens 89 to become parallel light and then enters the opening 8b of the light blocking switching plate 84.

According to the modification of the fourth embodiment described above, in addition to the above-described effects, by providing the diffusion plate 52, even if the positions of the

mirrors

86 and 87 slightly fluctuate, the change in the amount of light passing through the slit 4a is reduced. The number of the mirrors as the direction conversion means is not limited to two, and may be one or three.

(first application example)

Fig. 8 is a schematic diagram showing a two-beam measurement system 100A as a first application example of the spectroscopic measurement apparatus according to the embodiment of the present invention. In the figure, cross-sectional structure examples of the respective optical fibers are also shown. The dual beam measurement system 100A includes the spectrometry device 1A of the first embodiment, and further includes a branch optical fiber 101, output

optical fibers

102 and 103, and a light blocking switch plate 108.

The branch optical fiber 101 splits light from a light source, not shown, into two light beams, and irradiates the measurement object Sam and the reference Ref. The light source includes, for example, a tungsten lamp and a deuterium lamp. The output optical fiber 102 supplies the transmitted light transmitted from the reference Ref to one optical fiber 91 of the spectrometer 1A. The output optical fiber 103 supplies the transmitted light transmitted from the measurement object Sam to the other optical fiber 92 of the spectroscopic measurement apparatus 1A.

The light-shielding switching plate 108 supplies only light from one of the

output fibers

102 and 103 to the spectrometry device 1A through the opening, and blocks light from the other. By switching the light-shielding switching plate 108, the transmitted light transmitted through the measurement object Sam and the transmitted light transmitted through the reference Ref are subjected to spectroscopic measurement in this order. Since the operation of the photometric device 1A is described above, detailed description is not repeated.

Here, as shown in the illustrated example, when the two

optical fibers

91 and 92 connected to the optical fiber coupling section 5A are assumed to include four optical fibers 99, respectively, a total of eight optical fibers 99 are introduced into the optical fiber coupling section 5A, and even if one of the optical fibers is shielded from light by the light shielding switching plate 108, light is supplied to the diffusion plate 52 through the four optical fibers 99, which are half of the optical fibers.

(second application example)

Fig. 9 is a schematic diagram showing a two-beam measurement system 100B as a second application example of the spectroscopic measurement apparatus according to the embodiment of the present invention. In the figure, cross-sectional structure examples of the respective optical fibers are also shown. The dual beam measurement system 100B includes the spectrometry device 10 according to the fourth embodiment, and further includes a branch optical fiber 101.

In the dual beam measurement system 100B, since the spectroscopic measurement apparatus 10 includes the optical fiber switching unit 8, the output

optical fibers

102 and 103 and the light blocking switching plate 108 are omitted as compared with the dual beam measurement system 100A of the first application example.

The transmitted light transmitted from the reference Ref is supplied to one optical fiber 91 of the spectrometry device 10, and the transmitted light transmitted from the measurement object Sam is supplied to the other optical fiber 92 of the spectrometry device 1A.

The transmitted light transmitted through the measurement object Sam and the transmitted light transmitted through the reference Ref are sequentially measured for spectral distribution by switching the light-shielding switching plate 82 included in the optical fiber switching unit 8. Since the operation of the photometric device 10 is described above, detailed description thereof will not be repeated.

Here, as shown in the illustrated example, when the two

optical fibers

91 and 92 connected to the optical fiber switching unit 8 are assumed to include four optical fibers 99, respectively, a total of eight optical fibers 99 are introduced into the optical fiber switching unit 8, and even if one optical fiber is shielded by the light shielding switching plate 82, light is supplied to the diffusion plate 52 through the four optical fibers 99, which are half of the optical fibers.

(reference example)

Fig. 10 is a schematic diagram showing a dual beam measurement system of a reference example. In the figure, cross-sectional structure examples of the respective optical fibers are also shown. The dual beam measurement system of the reference example includes a branch optical fiber 101, output

optical fibers

102 and 103, a light blocking switching plate 108, a branch optical fiber 104, and a spectroscopic measurement device 106.

The branch optical fiber 104 combines the transmitted light supplied from the output optical fiber 102 and transmitted through the reference Ref and the transmitted light supplied from the output optical fiber 103 and transmitted through the measurement object Sam into one light beam, and emits the light beam from the emission end 104 c. The emission end 104c of the branch optical fiber 104 is fixed so as to be close to the slit 105 of the spectrometry device 106, and the light emitted from the emission end 104c enters the spectrometry device 106 through the slit 105.

The exit end 104c of the branch optical fiber 104 includes a plurality of optical fiber lines 104 d. Of these, half of the optical fiber lines 104d belong to one incident end 104a, and the remaining half of the optical fiber lines 104d belong to the other incident end 104 b. The plurality of optical fiber wires 104d included in the emission end 104c are fixed so as to be aligned in a line along the slit 105. Therefore, the number of the optical fiber lines 104d is limited by the length of the slit 105.

Here, as shown in the illustrated example, when the maximum number of the optical fiber lines 104d aligned in a line along the slit 105 is four in total, only two optical fiber lines 104d are present at the incident ends 104a and 104b of the branch optical fiber 104. Therefore, even if the number of optical fiber lines of the upstream output

optical fibers

102 and 103 is increased, the branch optical fiber 104 becomes a bottleneck and cannot supply a sufficient amount of light to the slit 105.

In contrast, in the

spectroscopic measurement apparatuses

1A and 10 of the present embodiment shown in fig. 8 and 9, the number and the diameter of the optical fiber 99 included in the

optical fibers

91 and 92 connected to the optical fiber coupling unit 5 or the optical fiber switching unit 8 are not limited by the length of the slit 4a, and therefore, light can be supplied through a larger number of optical fiber 99 than in the case of being arranged along the slit 4 a. Further, light can be supplied through the optical fiber 99 having a large element diameter. In many cases, when an optical fiber having a large element diameter is used, the loss of light intensity as the entire measurement system is reduced. Therefore, even if there is a slight loss of the light amount in the diffusion plate 52, a sufficient amount of light can be supplied to the spectroscopic measurement unit 3.

(third application example)

Fig. 11 is a schematic diagram showing a reflected light measurement system 200 as a third application example of the spectroscopic measurement apparatus according to the embodiment of the present invention. The reflected light measurement system 200 includes the spectroscopic measurement device 10 according to the fourth embodiment, and further includes a light source device 201 and a light distributor 205.

The reflected light measurement system 200 performs spectroscopic measurement (Ref) on reflected light of a substance having a known spectral reflectance in advance, and then performs spectroscopic measurement on reflected light generated on the surface of the measurement object Sam to evaluate the spectral reflectance characteristics and the film thickness of the measurement object Sam. The reflected light measurement system 200 is used for, for example, an application of evaluating the film thickness of a film or the like produced in the longitudinal direction at a plurality of points in the width direction.

The light source device 201 generates light having a wavelength band suitable for the reflected light generated by the measurement object Sam. Light generated from the light source device 201 is guided to the light distributor 205 through the connection fiber 203. The light distributor 205 distributes light from the light source device 201 into a plurality of paths. In the illustrated example, the optical splitter 205 splits the light from the light source device 201 into five paths.

Five Y-shaped branch optical fibers are connected to the other end of the optical splitter 205, and the divided light is output to the input optical fibers 207-1 to 5 of the corresponding Y-shaped branch optical fibers. The top ends of the input optical fibers 207-1 to 5 are connected with outgoing/incoming portions 209-1 to 5, respectively. Then, each light divided by the optical splitter 205 is irradiated from each of the emission/incidence parts 209-1 to 5 toward the measurement object Sam.

A component corresponding to the surface state of the measurement target Sam in the light irradiated to the measurement target Sam is generated as reflected light. The generated reflected light is then incident again on the emission/incidence parts 209-1 to 5, respectively.

The reflected light entering the exit/entrance sections 209-1 to 5 is guided to the optical fiber switching section 8 of the spectrometer 10 through the corresponding output optical fibers 211-1 to 5 of the Y-shaped branch optical fiber. Since the operation of the photometric device 10 is described above, detailed description thereof will not be repeated.

(fourth application example)

Fig. 12 is a schematic diagram showing a transmitted light measurement system 300 as a fourth application example of the spectroscopic measurement apparatus according to the embodiment of the present invention. The transmission light measurement system 300 includes the spectroscopic measurement device 10 according to the fourth embodiment, and further includes a light source device 301 and a light distributor 305.

The transmitted light measurement system 300 performs spectroscopic measurement (Ref) on the transmitted light in a state where the measurement object Sam is not present in advance, and then measures the light transmitted from the measurement object Sam to evaluate the spectroscopic transmission (absorption) characteristics, chromaticity, and the like of the measurement object Sam. The transmission light measurement system 300 is used for, for example, an application of evaluating chromaticity of a film or the like produced in a longitudinal direction at a plurality of points in a width direction.

The light source device 301 generates light having a wavelength band suitable for the transmitted light generated by the measurement object Sam. Light generated from the light source device 301 is guided to the light distributor 305 through the connection fiber 303. The light distributor 305 distributes the light from the light source device 301 into a plurality of paths. In the illustrated example, the optical splitter 305 splits the light from the light source device 301 into five paths.

Input optical fibers 307-1 to 5 for guiding light to emission units 309-1 to 5 arranged on one side of the measurement object Sam are connected to the other end of the optical distributor 305. Then, the lights divided by the optical splitter 305 are emitted from the emission units 309-1 to 5 toward the measurement object Sam.

The component transmitted from the measurement target Sam in the light irradiated to the measurement target Sam is generated as transmitted light. The generated transmitted light is incident on the incident portions 311-1 to 5 arranged on the other side of the measurement object Sam.

The transmitted light incident on the incident portions 311-1 to 5 is guided to the optical fiber switching portion 8 of the spectroscopic measurement apparatus 10 through the corresponding output optical fibers 313-1 to 5. Since the operation of the photometric device 10 is described above, detailed description thereof will not be repeated.

While the embodiments of the present invention have been described above, it is needless to say that the present invention is not limited to the above embodiments, and various modifications can be made by those skilled in the art.

Claims

1. A spectroscopic measurement device is provided with:

a spectroscopic measurement unit for performing spectroscopic measurement of light incident through the slit; and

a light diffusion means for diffusing light supplied from the plurality of optical fibers and physically fixing the diffused light to the slit so that the light is incident on the slit directly or via a lens or a mirror,

the light diffusion unit is a diffusion plate,

light supplied from the plurality of optical fibers is incident on one surface of the diffusion plate, and the diffused light is emitted from the other surface of the diffusion plate,

the exit ends of the plurality of optical fibers are arranged so as to be deviated from the optical axis passing through the slit, surround the optical axis, and be inclined to the optical axis, and emit light in a direction toward the slit.

2. The spectrometry apparatus according to claim 1, further comprising:

a diaphragm that restricts a beam of the diffused light toward the slit.

3. The spectrometry apparatus according to claim 1 or 2, further comprising:

the plurality of optical fibers supply light to the light diffusion unit.

4. The spectrometry apparatus according to claim 1, further comprising:

and a light shielding switching unit supplying light from a selected part of the plurality of optical fibers to the light diffusion unit and shielding light from the remaining optical fibers.