Spectroscopic measurement device and spectroscopic measurement method

Abstract

An analysis unit in a spectrometric measurement device uses a first correction factor to correct a first electric signal such that the linear characteristic of a first amplifier matches a reference linear characteristic. The analysis unit uses the second correction factor to correct the second electrical signal such that the linear characteristic of the second amplifier coincides with the reference linear characteristic. The analysis unit generates first spectral data on the basis of the corrected first electrical signal, and generates second spectral data on the basis of the corrected second electrical signal. The analysis unit generates spectral data of the light to be measured on the basis of the first spectral data and the second spectral data.

Description

Technical Field

[0001] The present invention relates to a spectrophotometric device and a spectrophotometric method. Background Art

[0002] There is known a spectrophotometric device comprising: an optical system for spectroscopically spectroscopically measuring light to be measured; a photodetector for receiving spectroscopic images of the spectroscopically spectroscopically measuring light in a first region with a short exposure time and a second region with a long exposure time; and an analysis unit for generating spectrum data of the spectrophotometric light based on first spectrum data generated based on the detection result in the first region and second spectrum data generated based on the detection result in the second region (see, for example, Patent Document 1). According to such a spectrophotometric device, spectrum data of the spectrophotometric light can be generated in a wide dynamic range.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2020-118477 Summary of the invention

[0006] Problems to be solved by the invention

[0007] In the above-mentioned spectrophotometric measuring device, there is a concern that an error due to factors other than the difference in exposure time may occur between the first spectrum data and the second spectrum data. If spectrum data of the light to be measured is generated based on the first spectrum data and the second spectrum data in a state where such an error occurs, there is a concern that the accuracy of the spectrum data of the light to be measured may be reduced.

[0008] An object of the present invention is to provide a spectroscopic measurement device and a spectroscopic measurement method capable of acquiring high-precision spectrum data of measured light.

[0009] Technical means of solving problems

[0010] A spectrophotometric device according to one aspect of the present invention is, [1] "a spectrophotometric device comprising: an optical system for spectroscopically spectroscopically measuring light to be measured; a photodetector for detecting a spectroscopic image of the light to be measured spectroscopically measured by the optical system; and an analyzing unit for generating spectrum data of the light to be measured, the photodetector comprising: a first light receiving unit having a plurality of first pixel columns arranged in a horizontal direction parallel to a wavelength axis of the spectrophotometric image, the plurality of first pixel columns respectively comprising a plurality of first pixels arranged in a vertical direction perpendicular to the wavelength axis; and a second light receiving unit having a first pixel column arranged in a vertical direction parallel to the wavelength axis. The first light receiving section is arranged in parallel and has a plurality of second pixel columns arranged in the horizontal direction, and the plurality of second pixel columns respectively include a plurality of second pixels arranged in the vertical direction; a first vertical transfer section, which transfers the first charges accumulated in each of the plurality of first pixels by receiving the split image in the first light receiving section with a first exposure time along the vertical direction according to each of the plurality of first pixel columns; a first horizontal transfer section, which transfers the first charges transferred by the first vertical transfer section along the horizontal direction; a first amplifier, whose output is connected to the first charge transferred by the first horizontal transfer section. a first electric signal corresponding to the amount of the first electric charge; a second vertical transfer unit, which transfers the second electric charge accumulated in each of the plurality of second pixels by receiving the spectral image in the second light receiving unit with a second exposure time longer than the first exposure time, along the vertical direction according to each of the plurality of second pixel columns; a second horizontal transfer unit, which transfers the second electric charge transferred by the second vertical transfer unit along the horizontal direction; and a second amplifier, which outputs a second electric signal corresponding to the amount of the second electric charge transferred by the second horizontal transfer unit, and the analyzing unit stores the second electric signal used to generate the second electric charge with the first amplifier. The invention further comprises the steps of: storing a first correction coefficient for correcting the first electrical signal in a manner that the linear characteristic of the second amplifier is consistent with the reference linear characteristic; storing a second correction coefficient for correcting the second electrical signal in a manner that the linear characteristic of the second amplifier is consistent with the reference linear characteristic; correcting the first electrical signal using the first correction coefficient; correcting the second electrical signal using the second correction coefficient; generating first spectral data based on the corrected first electrical signal; generating second spectral data based on the corrected second electrical signal; and generating the spectral data of the measured light based on the first spectral data and the second spectral data.

[0011] In the spectrophotometric device described in [1] above, the photodetector receives the spectrophotometric image at a first exposure time in the first light receiving section and outputs a first electrical signal, and receives the spectrophotometric image at a second exposure time longer than the first exposure time in the second light receiving section and outputs a second electrical signal, and the analysis section generates first spectral data based on the first electrical signal and generates second spectral data based on the second electrical signal. Then, the analysis section generates spectral data of the light to be measured based on the first spectral data and the second spectral data. Thus, spectral data of the light to be measured can be generated in a wide dynamic range. Furthermore, in the spectrophotometric device described in [1] above, the analysis section corrects the first electrical signal using the first correction coefficient and corrects the second electrical signal using the second correction coefficient. Thus, errors generated in the linear characteristics of the first amplifier and the linear characteristics of the second amplifier can be corrected. Therefore, according to the spectrophotometric device described in [1] above, high-precision spectral data of the light to be measured can be obtained.

[0012] A spectrophotometric device according to one aspect of the present invention may be, [2] "a spectrophotometric device as described in [1] above, wherein the analyzing unit generates the first spectral data based on a first correspondence between each of the plurality of first pixel columns and a wavelength in the wavelength axis; and generates the second spectral data based on a second correspondence between each of the plurality of second pixel columns and a wavelength in the wavelength axis". In the spectrophotometric device, there is a situation where the position of the first pixel column of a light image of a certain wavelength in the imaged spectrophotometric image and the position of the second pixel column of the imaged light image are offset. According to the spectrophotometric device described in [2], even when such a positional offset occurs, the first spectral data and the second spectral data in which such a positional offset is corrected can be obtained.

[0013] A spectrophotometric device according to one aspect of the present invention may be, [3] "a spectrophotometric device as described in [1] or [2] above, wherein the analyzing unit corrects at least one of the first spectral data and the second spectral data based on a ratio of a representative value of the intensity of the first spectral data to a representative value of the intensity of the second spectral data". In the spectrophotometric device, there may be a difference between the light intensity of a first pixel column of a light image of a certain wavelength in an imaged spectral image and the light intensity of a second pixel column of the light image. According to the spectrophotometric device described in [3], even when such a light intensity difference occurs, the first spectral data and the second spectral data in which such a light intensity difference is corrected can be obtained.

[0014] A spectroscopic measurement device according to one aspect of the present invention may be, [4] "a spectroscopic measurement device as described in any one of [1] to [3] above, wherein the analysis unit performs a correction on the second spectral data for removing stray light generated in the optical system". If only the noise generated in the circuit is considered, the S / N of the second spectral data is higher than the S / N of the first spectral data. However, there is a case where the measured light contains stray light. In this case, the noise caused by the stray light increases by an amount that the second exposure time is longer than the first exposure time, and the S / N of the second spectral data decreases. According to the spectroscopic measurement device described in [4], even when the measured light contains stray light, the second spectral data with such stray light removed can be obtained.

[0015] A spectroscopic measurement device according to one aspect of the present invention may be, [5] "a spectroscopic measurement device as described in any one of [1] to [4], further comprising: a bundle fiber, comprising a plurality of optical fibers for guiding the light to be measured toward the optical system, having a circular incident end face and an elongated exit end face, wherein the plurality of optical fibers comprises: a plurality of first optical fibers arranged on one side of the exit end face relative to the center of the exit end face; and a plurality of second optical fibers arranged on the other side of the exit end face relative to the center of the exit end face, wherein each of the plurality of first optical fibers and each of the plurality of second optical fibers are adjacent to each other in at least one of a circumferential direction and a radial direction on the incident end face". In the spectroscopic measurement device described in [5], even when the light intensity of the light to be measured varies on the incident end face of the bundle fiber, the light intensity of the light to be measured is suppressed on the exit end face of the bundle fiber. Therefore, according to the spectroscopic measuring device described in [5], when focusing on the first pixel column and the second pixel column of the light image of a certain wavelength in the imaging spectroscopic image, the difference between the light intensity of the first pixel column and the light intensity of the second pixel column can be suppressed, and the first spectral data and the second spectral data can be obtained.

[0016] A spectroscopic measurement device according to one aspect of the present invention may also be, [6] "a spectroscopic measurement device as described in any one of [1] to [5] above, further comprising: a bundle optical fiber including a plurality of optical fibers for guiding the light to be measured toward the optical system; and a light diffusion unit disposed at a front section of the bundle optical fiber for guiding the light to be measured toward an incident end face of the bundle optical fiber in a diffused state". In the spectroscopic measurement device described in [6], since the light to be measured diffused by the light diffusion unit is incident on the incident end face of the bundle optical fiber, the deviation of the light intensity of the light to be measured is suppressed on the incident end face of the bundle optical fiber. Therefore, according to the spectroscopic measurement device described in [6], when focusing on the first pixel column and the second pixel column of a light image of a certain wavelength in the imaged spectroscopic image, the difference between the light intensity of the first pixel column and the light intensity of the second pixel column can be suppressed, and the first spectral data and the second spectral data can be obtained.

[0017] The spectrophotometer according to one aspect of the present invention may be, [7] "a spectrophotometer as described in any one of [1] to [6] above, wherein the photodetector has an electronic shutter function, the electronic shutter function discharging the first charges accumulated in each of the plurality of first pixels over a predetermined time from the first frame time in a frame time from when the first vertical transfer unit starts transferring the first charges to when the first horizontal transfer unit ends transferring the first charges, thereby setting the time other than the predetermined time in the frame time as the first exposure time; the analysis unit, when using the electronic shutter function, associates and stores a third correction coefficient for correcting the first electrical signal in such a manner that the linear characteristic of the first amplifier is consistent with the reference linear characteristic; and corrects the first electrical signal using the third correction coefficient". When the electronic shutter function is used for the first light receiving unit, the intensity of the first electrical signal decreases as the length of the predetermined time increases, but strictly speaking, the intensity of the first electrical signal does not decrease linearly. According to the spectrometer described in [7], by correcting the first electrical signal using the third correction coefficient associated with a predetermined time, it is possible to obtain first spectrum data in which an error caused by the linear characteristics of the first amplifier is corrected.

[0018] The spectrophotometric device according to one aspect of the present invention may also be, [8] "a spectrophotometric device as described in [2] above, wherein the photodetector has an electronic shutter function, and the electronic shutter function discharges the first charge accumulated in each of the plurality of first pixels over a prescribed time starting from the first frame time within a frame time from when the first vertical transfer unit starts transferring the first charge to when the first horizontal transfer unit ends transferring the first charge, thereby setting the time other than the prescribed time in the one frame time as the first exposure time; and the analysis unit generates the first spectrum data based on the first correspondence corresponding to at least one of the prescribed time and the first exposure time". When the electronic shutter function is used for the first light receiving unit, there is a case where the correspondence between each of the plurality of first pixel columns and the wavelength in the wavelength axis is offset. According to the spectrometer described in [8], by generating the first spectrum data based on the first correspondence corresponding to at least one of the predetermined time and the first exposure time, the first spectrum data in which the deviation of the correspondence is corrected can be obtained.

[0019] The spectrometer according to one aspect of the present invention may be, [9] "a spectrometer as described in any one of [1] to [6] above, wherein the photodetector has an electronic shutter function, and the electronic shutter function discharges the first charges accumulated in each of the plurality of first pixels over a predetermined time from the beginning of the one frame time during a period from when the first vertical transfer unit starts transferring the first charges to when the first horizontal transfer unit ends transferring the first charges, thereby setting the time other than the predetermined time in the one frame time as the first exposure time". According to the spectrometer described in [9], by using the electronic shutter function for the first light receiving unit, saturation of each first pixel in the first light receiving unit can be prevented, and the first spectrum data can be reliably acquired in the saturation band.

[0020] The spectrophotometric device according to one aspect of the present invention may be,

[10] "a spectrophotometric device as described in any one of [1] to [9] above, wherein the analyzing unit generates a first function of the first spectral data and a second function of the second spectral data when exposing the first light receiving unit and the second light receiving unit to the same exposure time, and corrects at least one of the first spectral data and the second spectral data based on a ratio between the first function and the second function". In the spectrophotometric device, the light receiving sensitivity of the first light receiving unit and the light receiving sensitivity of the second light receiving unit are not necessarily the same. According to the spectrophotometric device described in

[10] , even when a shift in light receiving sensitivity occurs, the first spectral data and the second spectral data in which such a shift in light receiving sensitivity is corrected can be obtained.

[0021] The spectrometer according to one aspect of the present invention may be,

[11] "a spectrometer as described in any one of [1] to

[10] above, wherein the analyzing unit corrects at least one of the first spectral data and the second spectral data based on a ratio between the first exposure time and the second exposure time". According to the spectrometer described in

[11] , the first spectral data and the second spectral data in which the effect of the difference in exposure time on light intensity is corrected can be obtained.

[0022] A spectrophotometric device according to one aspect of the present invention is,

[12] "a spectrophotometric device comprising: an optical system for spectroscopically spectroscopically measuring light; a photodetector for detecting a spectroscopic image of the light to be measured spectroscopically measured by the optical system; and a storage unit, the photodetector comprising: a first light receiving unit having a plurality of first pixel columns arranged in a horizontal direction parallel to a wavelength axis of the spectrophotometric image, the plurality of first pixel columns respectively comprising a plurality of first pixels arranged in a vertical direction perpendicular to the wavelength axis; a second light receiving unit arranged side by side with the first light receiving unit in the vertical direction, having a plurality of second pixel columns arranged in the horizontal direction, the plurality of second pixel columns respectively comprising a plurality of second pixels arranged in the vertical direction; a first vertical transfer unit for transferring first charges accumulated in each of the plurality of first pixels by receiving the spectrophotometric image in the first light receiving unit for a first exposure time along the vertical direction for each of the plurality of first pixel columns; and a first horizontal transfer unit for transferring first charges stored in each of the plurality of first pixels by receiving the spectrophotometric image in the first light receiving unit for a first exposure time. The first charge transferred by the first vertical transfer section is transferred along the horizontal direction; the first amplifier outputs a first electrical signal corresponding to the amount of the first charge transferred by the first horizontal transfer section; the second vertical transfer section transfers the second charge accumulated in each of the plurality of second pixels by receiving the spectral image in the second light receiving section for a second exposure time longer than the first exposure time along the vertical direction according to each of the plurality of second pixel columns; the second horizontal transfer section transfers the second charge transferred by the second vertical transfer section along the horizontal direction; and the second amplifier outputs a second electrical signal corresponding to the amount of the second charge transferred by the second horizontal transfer section, the storage section storing a first correction coefficient for correcting the first electrical signal in a manner that the linear characteristic of the first amplifier is consistent with a reference linear characteristic; and storing a second correction coefficient for correcting the second electrical signal in a manner that the linear characteristic of the second amplifier is consistent with the reference linear characteristic.

[0023] In the spectrophotometric device described in

[12] above, the photodetector receives the spectrophotometric image at the first light receiving section with a first exposure time and outputs a first electrical signal, and receives the spectrophotometric image at the second light receiving section with a second exposure time longer than the first exposure time and outputs a second electrical signal. Then, the storage section stores a first correction coefficient for correcting the first electrical signal and a second correction coefficient for correcting the second electrical signal. Therefore, when the spectrum data of the measured light is generated based on the first electrical signal and the second electrical signal, the errors generated in the linear characteristics of the first amplifier and the linear characteristics of the second amplifier can be corrected by correcting the first electrical signal using the first correction coefficient and correcting the second electrical signal using the second correction coefficient. Therefore, according to the spectrophotometric device described in

[12] above, the spectrum data of the measured light can be obtained with high accuracy.

[0024] A spectroscopic measurement method according to one aspect of the present invention is,

[13] "a spectroscopic measurement method, which is a spectroscopic measurement method using a spectroscopic measurement device, the spectroscopic measurement device comprising: an optical system for spectroscopically measuring a light to be measured; a photodetector for detecting a spectroscopic image of the light to be measured spectroscopically measured by the optical system; and an analysis unit for generating spectral data of the light to be measured, the photodetector comprising: a first light receiving unit having a plurality of first pixel columns arranged in a horizontal direction parallel to a wavelength axis of the spectroscopic image, the plurality of first pixel columns respectively comprising pixels in a vertical direction perpendicular to the wavelength axis; a plurality of first pixels arranged in a vertical direction; a second light receiving unit, which is arranged side by side with the first light receiving unit in the vertical direction and has a plurality of second pixel columns arranged in the horizontal direction, wherein the plurality of second pixel columns respectively include the plurality of second pixels arranged in the vertical direction; a first vertical transfer unit, which transfers the first charges accumulated in each of the plurality of first pixels by receiving the spectroscopic image in the first light receiving unit with a first exposure time along the vertical direction according to each of the plurality of first pixel columns; a first horizontal transfer unit, which transfers the first charges transferred by the first vertical transfer unit a first amplifier which outputs a first electrical signal corresponding to the amount of the first electrical charge transmitted by the first horizontal transmission unit; a second vertical transmission unit which transmits the second electrical charge accumulated in each of the plurality of second pixels by receiving the spectral image in the second light receiving unit for a second exposure time longer than the first exposure time along the vertical direction according to each of the plurality of second pixel columns; a second horizontal transmission unit which transmits the second electrical charge transmitted by the second vertical transmission unit along the horizontal direction; and a second amplifier which outputs a first electrical signal corresponding to the amount of the first electrical charge transmitted by the second horizontal transmission unit. The second electric signal corresponding to the amount of the second charge transmitted by the transmitting unit, the spectroscopic measurement method comprises: the steps of correcting the first electric signal in a manner that the linear characteristics of the first amplifier are consistent with the reference linear characteristics, and correcting the second electric signal in a manner that the linear characteristics of the second amplifier are consistent with the reference linear characteristics; the step of generating the first spectrum data based on the corrected first electric signal, and the step of generating the second spectrum data based on the corrected second electric signal; and the step of generating the spectrum data of the measured light based on the first spectrum data and the second spectrum data.

[0025] According to the spectroscopic measurement method described in the above

[13] , for the same reason as the spectroscopic measurement device described in the above [1], it is possible to obtain high-precision spectrum data of the light to be measured.

[0026] Effects of the Invention

[0027] According to the present invention, it is possible to provide a spectroscopic measurement device and a spectroscopic measurement method capable of acquiring high-precision spectrum data of light to be measured. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This is a diagram showing the structure of a spectrophotometer according to one embodiment.

[0029] Figure 2 Yes Display Figure 1 The diagram shows the structures of the incident end face and the output end face of the bundled optical fiber.

[0030] Figure 3 Yes Display Figure 1 A diagram showing the structure of a photodetector.

[0031] Figure 4 This is a diagram for explaining the timing of exposure of each first pixel.

[0032] Figure 5 This is a diagram for explaining the timing of exposure of each first pixel.

[0033] Figure 6 This is a diagram for explaining the timing of exposure of each first pixel when the electronic shutter is used.

[0034] Figure 7 This is a diagram for explaining the timing of exposure of each first pixel when the electronic shutter is used.

[0035] Figure 8 This is a diagram for explaining the timing of exposure of each first pixel when the electronic shutter is used.

[0036] Fig. 9 This is a diagram showing the processing performed by the analysis unit.

[0037] Fig.10 It is a diagram showing the linear characteristics of each of the first amplifier and the second amplifier.

[0038] Fig.11 It is a diagram showing the correspondence relationship between the first exposure time and the first correction coefficient, and the correspondence relationship between the second exposure time and the second correction coefficient.

[0039] Fig.12 It is a diagram for explaining wavelength axis correction.

[0040] Fig.13 The diagram shows a first correspondence relationship between the position of the first pixel row and the wavelength of the spectral image, and a second correspondence relationship between the position of the second pixel row and the wavelength of the spectral image.

[0041] Fig.14 It is a diagram for explaining the generation of each of the first spectrum data and the second spectrum data.

[0042] Fig.15 It is a diagram for explaining the correction of input dependency.

[0043] Fig.16 This is a diagram for explaining stray light correction.

[0044] Fig.17 This is a diagram for explaining the generation of spectrum data of measured light.

[0045] Fig.18 This is a diagram showing the relationship between the charge discarding time and the intensity of the first electric signal when the electronic shutter is used.

[0046] Fig.19 It is a diagram showing the correspondence relationship between the charge discarding time and the third correction coefficient.

[0047] Fig. 20 It is a diagram showing the first correspondence relationship based on the first exposure time correction.

[0048] Fig.21 It is a diagram for explaining the anti-blooming function of the photodetector.

[0049] Fig. 22 It is a figure for demonstrating the light diffusion part. DETAILED DESCRIPTION

[0050] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. In addition, the same or corresponding parts are denoted by the same reference numerals in each figure, and repeated descriptions are omitted.

[0051] [Structure of Spectrophotometer]

[0052] like Figure 1 As shown, the spectroscopic measurement device 1 includes a spectrometer 10 and a computer device 20. The computer device 20 is, for example, a personal computer, and is composed of a processing unit, a storage unit, a display unit, and an input unit. The processing unit is composed of a processor, a memory, a storage device, and a communication device, and processes various data by executing software (programs). The storage unit is a hard disk, etc., which stores various data. The display unit is a display, etc., which displays various data to the operator. The input unit is a mouse and a keyboard, etc., which accepts input of various data from the operator. The spectrometer 10 includes a bundled optical fiber 2, an optical system 3, a light detector 4, a storage unit 7, a control substrate 8, and a housing 9. In the present embodiment, the storage unit 7, the control substrate 8, and the computer device 20 constitute an analysis unit 70 that generates spectral data of the light to be measured L1. The spectroscopic measurement device 1 is a device that generates spectral data of the light to be measured L1 by spectroscopically analyzing the light to be measured L1.

[0053] The bundle optical fiber 2 guides the measured light L1 to the optical system 3. The bundle optical fiber 2 has a circular incident end face 2a and a long strip-shaped emission end face 2b. The bundle optical fiber 2 includes a plurality of optical fibers. Figure 2As shown in (a) and (b) of FIG. 8 , the bundled optical fiber 2 includes a plurality of first optical fibers 21 , a plurality of second optical fibers 22 , a plurality of third optical fibers 23 , and a fourth optical fiber 24 .

[0054] The structure of the incident end face 2a of the bundled optical fiber 2 is as follows. Figure 2 As shown in (a), the fourth optical fiber 24 is arranged at the center of the incident end face 2a. A plurality of third optical fibers 23 are arranged along the outer edge of the incident end face 2a. Each of the plurality of third optical fibers 23 is arranged at a prescribed interval. A plurality of first optical fibers 21 and a plurality of second optical fibers 22 are arranged between the fourth optical fiber 24 and the third optical fibers 23, and between each of the plurality of third optical fibers 23. Each of the plurality of first optical fibers 21 and each of the plurality of second optical fibers 22 are arranged adjacent to each other in the circumferential direction of the incident end face 2a. Each of the plurality of first optical fibers 21 and each of the plurality of second optical fibers 22 may also be arranged adjacent to each other in the radial direction of the incident end face 2a.

[0055] The structure of the emission end face 2b of the bundled optical fiber 2 is as follows. Figure 2 As shown in (b), the 4th optical fiber 24 is arranged at the center of the output end face 2b. The plurality of third optical fibers 23 are arranged at both ends of the output end face 2b. The plurality of first optical fibers 21 are arranged between the 4th optical fiber 24 and the plurality of third optical fibers 23 arranged at one end of the output end face 2b. In other words, the plurality of first optical fibers 21 are arranged on one side relative to the center of the output end face 2b. The plurality of second optical fibers 22 are arranged between the 4th optical fiber 24 and the plurality of third optical fibers 23 arranged at the other end of the output end face 2b. In other words, the plurality of second optical fibers 22 are arranged on the other side relative to the center of the output end face 2b.

[0056] like Figure 1 As shown, the optical system 3 has a light incident portion 31, a diffraction grating 32, and a lens 33. The optical system 3 guides the measured light L1 to the photodetector 4, and forms a spectroscopic image of the measured light L1 on the light receiving portion of the photodetector 4. In the present embodiment, the optical system 3 is a Dyson optical system. In addition, in the present embodiment, the diffraction grating 32 is a reflective diffraction grating. The measured light L1 is split by the diffraction grating 32 in a direction perpendicular to the incident direction of the measured light L1. Here, the direction in which the measured light L1 is split is referred to as the X-axis direction, the direction perpendicular to the X-axis direction is referred to as the Y-axis direction, and the direction perpendicular to the X-axis direction and the Y-axis direction is referred to as the Z-axis direction.

[0057] The light incident portion 31 is connected to the emission end face 2b of the bundle optical fiber 2. The emission end face 2b of the bundle optical fiber 2 is connected to the light incident portion 31 in a state where the Y-axis direction is the long side direction when viewed from the Z-axis direction. The light incident portion 31 allows the measured light L1 guided from the bundle optical fiber 2 to be incident into the optical system 3. The light incident portion 31 adjusts the incident amount of the measured light L1. The light incident portion 31 is, for example, a slit member. The slit formed in the slit member is opened in a rectangular shape with the X-axis direction as the short side and the Y-axis direction as the long side when viewed from the Z-axis direction.

[0058] The diffraction grating 32 is opposite to the light incident portion 31 in the Z-axis direction. The diffraction grating 32 is composed of a plurality of grating grooves (not shown). The plurality of grating grooves are arranged along the X-axis direction in a state where each grating groove extends in the Y-axis direction. The measured light L1 incident on the diffraction grating 32 is split according to the wavelength along the direction in which the plurality of grating grooves are arranged, that is, the X-axis direction.

[0059] The lens 33 is disposed between the light incident portion 31, the photodetector 4, and the diffraction grating 32 in the Z-axis direction. The lens 33 guides the measured light L1 incident from the light incident portion 31 to the diffraction grating 32, and forms a spectroscopic image of the measured light L1 dispersed by the diffraction grating 32 at the light receiving portion of the photodetector 4.

[0060] The photodetector 4 faces the diffraction grating 32 in the Z-axis direction. The photodetector 4 detects the light to be measured L1 dispersed by the diffraction grating 32. In the present embodiment, the photodetector 4 is a full-frame transfer type CCD image sensor.

[0061] The storage unit 7 and the photodetector 4 are mounted on the control substrate 8. The storage unit 7 stores a correction coefficient for correcting the data detected by the photodetector 4. The storage unit 7 is a storage medium such as a RAM (Random Access Memory) or a ROM (Read Only Memory). The computer device 20 is electrically connected to the control substrate 8. The computer device 20 obtains data from the photodetector 4 and obtains the correction coefficient from the storage unit 7, and generates spectrum data of the measured light L1 after correcting the data.

[0062] The housing 9 accommodates the diffraction grating 32 , the lens 33 , the photodetector 4 , and the storage unit 7 . The light incident unit 31 and the control substrate 8 are mounted on a wall of the housing 9 .

[0063] [Structure and operation of the photodetector]

[0064] like Figure 3As shown, the photodetector 4 has a first light receiving portion 5 and a second light receiving portion 6. The first light receiving portion 5 and the second light receiving portion 6 are arranged side by side along the Y-axis direction. The wavelength axis A of the spectral image α formed on the first light receiving portion 5 and the second light receiving portion 6 extends along the X-axis direction. The image of each wavelength of the spectral image α extends along the Y-axis direction. The spectral image α preferably has a shape that is line-symmetrical about the boundary line between the first light receiving portion 5 and the second light receiving portion 6.

[0065] The first light receiving unit 5 has a plurality of first pixel columns 51 arranged in the X-axis direction. The plurality of first pixel columns 51 respectively include a plurality of first pixels 52 arranged in the Y-axis direction. The first light receiving unit 5 has, for example, 2168 first pixel columns 51. Each of the plurality of first pixel columns 51 includes, for example, 128 first pixels 52. The second light receiving unit 6 has a plurality of second pixel columns 61 arranged in the X-axis direction. The plurality of second pixel columns 61 respectively include a plurality of second pixels 62 arranged in the Y-axis direction. The second light receiving unit 6 has, for example, 2168 second pixel columns 61. Each of the plurality of second pixel columns 61 includes, for example, 128 second pixels 62. Each of the plurality of first pixels 52 generates and accumulates a first charge Q1 of an amount corresponding to the intensity of the received spectral image α by receiving the spectral image α with the first exposure time. Each of the plurality of second pixels 62 generates and accumulates second electric charge Q2 of an amount corresponding to the intensity of the received spectral image α by receiving the spectral image α during the second exposure time. The first exposure time is shorter than the second exposure time.

[0066] The photodetector 4 further includes a first vertical transfer section 41, a first horizontal transfer section 42, and a first amplifier 43. The first vertical transfer section 41 transfers the first charge Q1 accumulated in each of the plurality of first pixels 52 in the Y-axis direction. Hereinafter, the transfer in the Y-axis direction is referred to as "transfer in the vertical direction". In the present embodiment, since the photodetector 4 is a CCD image sensor of a full-frame transfer type, the first vertical transfer section 41 is not distinguished from each first pixel column 51. In this case, the first vertical transfer section 41 is a plurality of transfer electrodes (not shown) that transfer the first charge Q1 in the vertical direction along each first pixel column 51. The first horizontal transfer section 42 is adjacent to the first light receiving section 5 on the opposite side to the second light receiving section 6 and extends in the X-axis direction. The first horizontal transfer section 42 transfers the first charge Q1 transferred from each first pixel column 51 by the first vertical transfer section 41 in the X-axis direction. Hereinafter, the transfer in the X-axis direction is referred to as "transfer in the horizontal direction".

[0067] The photodetector 4 further includes a second vertical transfer section 44, a second horizontal transfer section 45, and a second amplifier 46. The second vertical transfer section 44 transfers the second charge Q2 accumulated in each of the plurality of second pixels 62 in the vertical direction. In the present embodiment, since the photodetector 4 is a full-frame transfer type CCD image sensor, the second vertical transfer section 44 is not distinguished from each second pixel column 61. In this case, the second vertical transfer section 44 is a plurality of transfer electrodes (not shown) that transfer the second charge Q2 in the vertical direction along each second pixel column 61. The second horizontal transfer section 45 is adjacent to the second light receiving section 6 on the opposite side to the first light receiving section 5, and extends in the X-axis direction. The second horizontal transfer section 45 transfers the second charge Q2 transferred from each second pixel column 61 by the second vertical transfer section 44 in the horizontal direction.

[0068] In the present embodiment, the photodetector 4 performs vertical transfer and horizontal transfer in FVB (Full Vertical Binning). On the first light receiving unit 5 side, the first charges Q1 of the plurality of first pixels 52 are added for each first pixel column 51 in the first horizontal transfer unit 42. Subsequently, the first charges Q1 added for each first pixel column 51 in the first horizontal transfer unit 42 are sequentially horizontally transferred from the first horizontal transfer unit 42. The photodetector 4 operates from the start of the transfer of the first charges Q1 from the first vertical transfer unit 41 to the end of the transfer of the first charges Q1 in the first horizontal transfer unit 42 as one frame operation. The first amplifier 43 generates a first electrical signal ES1 corresponding to the amount of the first charges Q1 transferred from the first horizontal transfer unit 42. The first electrical signal ES1 is, for example, a voltage value. The first electrical signal ES1 is converted into a digital value by an AD converter (not shown).

[0069] On the second light receiving section 6 side, the second charges Q2 of the plurality of second pixels 62 are added for each second pixel column 61 in the second horizontal transfer section 45. Subsequently, the second charges Q2 added for each second pixel column 61 in the second horizontal transfer section 45 are sequentially horizontally transferred from the second horizontal transfer section 45. The photodetector 4 operates as one frame operation from the start of the transfer of the second charges Q2 from the second vertical transfer section 44 to the end of the transfer of the second charges Q2 by the second horizontal transfer section 45. The second amplifier 46 generates a second electric signal ES2 corresponding to the amount of the second charges Q2 transferred from the second horizontal transfer section 45. The second electric signal ES2 is, for example, a voltage value. The second electric signal ES2 is converted into a digital value by an AD converter (not shown).

[0070] Focusing on one first pixel row 51, the timing of exposure of each first pixel 52 in each frame operation will be described. Figure 4, the exposure timing of each first pixel 52 from the start of vertical transfer of the first charge Q1 by the first vertical transfer unit 41 to the end of vertical transfer is described. Here, for the sake of simplicity, the first pixel 52a (in Figure 4 a), the first pixel 52b (in Figure 4 b), the first pixel 52c (in Figure 4 c) and the first pixel 52d (in Figure 4 The first pixel 52a to the first pixel 52d are arranged in the order of the first pixel 52d, the first pixel 52c, the first pixel 52b, and the first pixel 52a starting from the side close to the first horizontal transfer unit 42. The exposure time t0 to t4 shows the prescribed timing in the first exposure time.

[0071] Before exposure time t0, it is assumed that in the previous frame operation, the first charge Q t0 The first charge Q is stored in each of the first pixels 52a to 52d. t0 The first charge Q is not vertically transferred to the first horizontal transfer unit 42 and remains. The vertical transfer in one frame operation is performed until the first charge Q is accumulated in the first pixel 52a in the first pixel column 51. t0 On the other hand, even after the exposure time t1, the first pixel column 51 continues to be exposed, so the first charge Q1 is newly accumulated. The first charge Q1 newly generated at the exposure time t1 is referred to as the first charge Q t1 , the first charge Q1 newly generated at exposure time t2 is set as the first charge Q t2 , the first charge Q1 newly generated at exposure time t3 is set as the first charge Q t3 , the first charge Q1 newly generated at exposure time t4 is set as the first charge Q t4 .

[0072] First, the first charge Q accumulated in the first pixel 52d during the exposure time t0 t0 is transferred to the first horizontal transfer unit 42. At this time, the first charge Q is newly accumulated. t1 Here, the first charge Q accumulated in the first pixel 52a in the first pixel column 51 is t1 Then, during the exposure time t2, the first charge Q accumulated in the first pixel 52c is transferred to the next frame operation. t0 , and the first charge Q accumulated in the first pixel 52d t1 is transferred to the first horizontal transfer unit 42. At this time, the first charge Q is newly accumulated. t2 Here, the first charge Q accumulated in the first pixel 52b in the first pixel column 51 is t2Then, during the exposure time t3, the first charge Q accumulated in the first pixel 52b is transferred to the next frame operation. t0 , the first charge Q accumulated in the first pixel 52c t1 , and the first charge Q accumulated in the first pixel 52d t2 is transferred to the first horizontal transfer unit 42. At this time, the first charge Q is newly accumulated. t3 Here, the first charge Q accumulated in the first pixel 52 c in the first pixel column 51 is t3 In the next frame the action is transmitted.

[0073] Finally, during the exposure time t4, the first charge Q accumulated in the first pixel 52a is t0 , the first charge Q accumulated in the first pixel 52b t1 , the first charge Q accumulated in the first pixel 52c t2 , and the first charge Q accumulated in the first pixel 52d t3 is transferred to the first horizontal transfer unit 42. At this time, the first charge Q is newly accumulated. t4 Here, the first charge Q accumulated in the first pixel 52d in the first pixel column 51 is t4 As described above, the exposure timing of each first pixel 52 for starting the transmission of the first charge Q1 in the next frame action is the earliest timing relative to the first pixel 52a (exposure time t1) and the latest timing relative to the first pixel 52d (exposure time t4).

[0074] Next, refer to Figure 5 , the timing of exposure of each first pixel 52 including the operation after completion of the vertical transfer is described. Figure 5 : represents a coordinate system in which the first exposure time is displayed on the horizontal axis and the position of each first pixel 52 is displayed on the vertical axis. Figure 3 The positions of the first pixels 52 in the Y-axis direction are consistent. Figure 5 In the example, the origin side is set to the opposite side to the first horizontal conveying section 42 ( Figure 3 The exposure time t1 to t4 is the boundary between the first light receiving part 5 and the second light receiving part 6. Figure 4 Similarly, the vertical transfer time VT from the start of vertical transfer of the first charge Q1 by the first vertical transfer unit 41 to the end of vertical transfer is shown. Next, the horizontal transfer by the first horizontal transfer unit 42 starts at exposure time t4, and ends at exposure time t5. The exposure time t4 to t5 shows the horizontal transfer time HT. The exposure time combining the vertical transfer time VT and the horizontal transfer time HT shows the one-frame time FT required for one-frame operation. Next, the vertical transfer in the next frame operation starts from exposure time t5, and ends at exposure time t6.

[0075] During the exposure time t1 to t4, if Figure 4 As described above, the exposure timing of each first pixel 52 for which the transfer of the first charge Q1 starts in the next frame operation is later than that of each first pixel 52 on the first horizontal transfer unit 42 side, and earlier than that of each first pixel 52 on the side opposite to the first horizontal transfer unit 42. In the exposure time t4 to t5, the first charge Q1 remaining without being vertically transferred in the previous frame operation is horizontally transferred, and all of the plurality of first pixels 52 are exposed at the same timing. In the exposure time t5 to t6, the exposure of each first pixel 52 for which the transfer of the first charge Q1 starts in the next frame operation is performed. That is, in the exposure time t5 to t6, the exposure of each first pixel 52 for which the transfer of the first charge Q1 starts in the next frame operation is completed. In the timing of the end of exposure, each first pixel 52 on the first horizontal transfer unit 42 side is later than that of each first pixel 52 on the side opposite to the first horizontal transfer unit 42. As described above, the shape of the exposure timing area 5a formed by the coordinate system with the horizontal axis as the first exposure time and the vertical axis as the position of each first pixel 52 becomes a parallelogram with relatively inclined short sides when the horizontal axis is set as the long side and the vertical axis is set as the short side.

[0076] The photodetector 4 can set the first exposure time to a time shorter than the 1 frame time FT. At this time, the photodetector 4 uses the electronic shutter function to discard the first accumulated charge Q1 over a predetermined time (charge discard time) from the beginning of the 1 frame time FT. Thus, the photodetector 4 can also set the remaining time in the 1 frame time FT as the first exposure time. Figure 6 As shown in FIG. 1 , when the electronic shutter is operated between the exposure time t1 and the exposure time t4, the first charges Q1 vertically transferred to the first horizontal transfer unit 42 in the vertical transfer and the first charges Q1 accumulated in the plurality of first pixels 52 in the vertical transfer are all discarded during the charge discard time DT. When the first exposure time ET1 is started, the vertical transfer and the accumulation of the first charges Q1 are restarted.

[0077] like Figure 7 As shown in FIG. 1 , when the electronic shutter is operated between exposure time t4 and exposure time t5, Figure 6In addition to the first charge Q1 discarded in the case of the exposure time t6, the first charge Q1 accumulated in the plurality of first pixels 52 during the horizontal transfer is also completely discarded. When the first exposure time ET1 starts, the horizontal transfer and the accumulation of the first charge Q1 are restarted. When the electronic shutter is operated between the exposure time t4 and the exposure time t5, the region 5a becomes a trapezoid. Specifically, the region 5a becomes a trapezoid in which the upper side is longer than the lower side when the side of the first horizontal transfer section 42 is set as the upper side and the side opposite to the first horizontal transfer section 42 is set as the lower side. When the region 5a becomes a trapezoid, the amount of the first charge Q1 transferred to the first horizontal transfer section 42 at the end of the exposure time t6 is such that the amount of charge accumulated in each of the first pixels 52 on the side of the first horizontal transfer section 42 is larger, and the amount of charge accumulated in each of the first pixels 52 on the side opposite to the first horizontal transfer section 42 is smaller.

[0078] like Figure 8 As shown in FIG. 1 , when the electronic shutter is operated between the exposure time t5 and the exposure time t6, the Figure 7 In addition to the first charge Q1 discarded in the case of the vertical transfer in the next frame operation, the first charge Q1 vertically transferred to the first horizontal transfer section 42 in the vertical transfer in the next frame operation and the first charge Q1 accumulated in the plurality of first pixels 52 in the vertical transfer are also all discarded. When the first exposure time ET1 starts, the vertical transfer in the next frame operation and the accumulation of the first charge Q1 are restarted. When the electronic shutter is operated between the exposure time t5 and the exposure time t6, the region 5a becomes a triangle. Specifically, the region 5a becomes a triangle with the first horizontal transfer section 42 side as the base and the side opposite to the first horizontal transfer section 42 as the vertex. When the region 5a becomes a triangle, the first charge Q1 transferred to the first horizontal transfer section 42 at the end of the exposure time t6 is, for example, only the charge of each first pixel 52 accumulated on the first horizontal transfer section 42 side.

[0079] [Generate spectral data using the analysis unit]

[0080] like Fig. 9 As shown in FIG. 1 , the analysis unit 70 generates spectrum data of the measured light L1 through a plurality of correction steps. The analysis unit 70 first performs linear correction ( S01 ). As an example of linear correction, Fig.10As shown, the linear characteristic R1 of the first amplifier 43 and the linear characteristic R2 of the second amplifier 46 are completely inconsistent. In addition, the linear characteristic R1 of the first amplifier 43 and the linear characteristic R2 of the second amplifier 46 are offset from the reference linear characteristic R0. The linear characteristic R1 of the first amplifier 43 and the linear characteristic R2 of the second amplifier 46 are represented by a graph in which the horizontal axis is the converted intensity of the electric signal and the vertical axis is the linear error. In the linear characteristic R1 of the first amplifier 43, the converted intensity of the first electric signal ES1 is calculated by (reference intensity / reference exposure time)×first exposure time ET1. In the linear characteristic R2 of the second amplifier 46, the converted intensity of the second electric signal ES2 is calculated by (reference intensity / reference exposure time)×second exposure time ET2. The linear error is represented by the absolute value of the difference between the intensity of the first electrical signal ES1 and the converted intensity of the first electrical signal ES1 in the case of the first amplifier 43, and is represented by the absolute value of the difference between the intensity of the second electrical signal ES2 and the converted intensity of the second electrical signal ES2 in the case of the second amplifier 46. In addition, the reference intensity is set to the signal intensity obtained at the reference exposure time. The reference exposure time is set to the shortest possible exposure time within the range that can guarantee the reliability of the data.

[0081] The linear error of the reference linear characteristic R0 becomes 0 based on the calculation formula of the linear error. The greater the conversion strength of the electric signal, the greater the magnitude of the linear error of the linear characteristic R1 of the first amplifier 43 and the linear characteristic R2 of the second amplifier 46. By making the linear characteristic R1 of the first amplifier 43 and the linear characteristic R2 of the second amplifier 46 consistent with the reference linear characteristic R0, the linear error of each of the linear characteristic R1 of the first amplifier 43 and the linear characteristic R2 of the second amplifier 46 can be corrected.

[0082] In the linear correction, the analysis unit 70 corrects the first electrical signal ES1 using the first correction coefficient k1. Fig.11As shown in (a), the analysis unit 70 stores a table TL1 of the first correction coefficient k1 corresponding to the converted intensity of the first electrical signal ES1 in the storage unit 7. The first correction coefficient k1 is predetermined based on the linear characteristic R1 of the first amplifier 43. The analysis unit 70 makes the linear characteristic R1 of the first amplifier 43 consistent with the reference linear characteristic R0 by multiplying the first correction coefficient k1 by the first electrical signal ES1. Therefore, the first correction coefficient k1 is determined in such a way that the larger the converted intensity of the first electrical signal ES1, the larger the correction amount of the linear characteristic R1. For example, the converted intensity of the first electrical signal ES1 is calculated as follows. An operator who performs spectroscopic measurement using the spectroscopic measurement device 1 gives an instruction about the value of the first exposure time ET1 to the analysis unit 70 using an input unit connected to the analysis unit 70. Then, the analysis unit 70 calculates the converted intensity of the first electrical signal ES1 based on the indicated value. For example, if the calculated converted intensity of the first electric signal ES1 is s11, the analyzing unit 70 reads k11 from the table TL1 as the corresponding first correction coefficient k1. Then, the analyzing unit 70 corrects the first electric signal ES1 using the read k11.

[0083] In the linear correction, the analysis unit 70 corrects the second electrical signal ES2 using the second correction coefficient k2. Fig.11 As shown in (b), the analysis unit 70 stores a table TL2 of the second correction coefficient k2 corresponding to the converted intensity of the second electrical signal ES2 in the storage unit 7. The second correction coefficient k2 is predetermined based on the linear characteristic R2 of the second amplifier 46. The analysis unit 70 makes the linear characteristic R2 of the second amplifier 46 consistent with the reference linear characteristic R0 by multiplying the second correction coefficient k2 by the second electrical signal ES2. Therefore, the second correction coefficient k2 is determined in such a way that the larger the converted intensity of the second electrical signal ES2, the larger the correction amount of the linear characteristic R2. For example, the converted intensity of the second electrical signal ES2 is calculated as follows. An operator who uses the spectroscopic measurement device 1 to perform spectroscopic measurement gives an instruction to the analysis unit 70 using an input unit connected to the analysis unit 70. Then, the analysis unit 70 calculates the converted intensity of the second electrical signal ES2 based on the indicated value. For example, if the calculated converted intensity of the second electrical signal ES2 is s21, the analysis unit 70 reads k21 from the table TL2 as the corresponding second correction coefficient k2. Then, the analyzing unit 70 corrects the second electric signal ES2 using the read k21. Note that, either the correction of the first electric signal ES1 or the correction of the second electric signal ES2 may be performed first or simultaneously.

[0084] The analysis unit 70 then performs wavelength axis correction (S02). Fig.12As shown, the image of each wavelength of the spectral image α has a case where it is an image in a shape parallel to the Y-axis direction (image of wavelength λ1) and a case where it is an image in an arcuate shape due to the characteristics of the optical system 3 (image of wavelength λ2). The analysis unit 70 sets a coordinate system in which the boundary line between the first light receiving unit 5 and the second light receiving unit 6 is set as the x-axis and the axis perpendicular to the x-axis is set as the y-axis. The analysis unit 70 sets a first correspondence relationship between the position on the wavelength axis of each of the plurality of first pixel columns 51 and the wavelength in the wavelength axis, and a second correspondence relationship between the position on the wavelength axis of each of the plurality of second pixel columns 61 and the wavelength in the wavelength axis in the coordinate system. The position on the wavelength axis of each of the plurality of first pixel columns 51 and the position on the wavelength axis of each of the plurality of second pixel columns 61 are set by the reference x coordinate WL0 (λ). The reference x coordinate WL0 (λ) is the x coordinate of the point where the image of each wavelength intersects the x-axis. For example, the reference x-coordinate WL0 (λ1) of the image of the wavelength λ1 is x1, and the reference x-coordinate WL0 (λ2) of the image of the wavelength λ2 is x2.

[0085] The position on the wavelength axis of the first pixel row 51 of the image of a certain wavelength in the imaged spectral image α and the position on the wavelength axis of the second pixel row 61 may be offset due to the characteristics of the optical system 3. In addition, the position on the wavelength axis of the first pixel row 51 and the position on the wavelength axis of the second pixel row 61 may have individual differences for each spectroscopic measurement device 1. Therefore, the position on the wavelength axis of the first pixel row 51 is measured in advance for each spectroscopic measurement device 1, and the analysis unit 70 calculates the position of the first pixel row 51 as follows: Fig.13 As shown in (a), the measurement results are stored in the first correspondence table TL3. Similarly, the position of the second pixel column 61 on the wavelength axis is measured in advance for each spectroscopic measurement device 1, and the analysis unit 70 stores the measured results in the first correspondence table TL3. Fig.13 As shown in (b), the measurement results are stored as a second correspondence table TL4. Fig.13 In (a), the position of the first pixel column 51 corresponding to the wavelength λ3 is x3. x3 is the reference x coordinate WL0(λ3) in the first pixel column 51. Fig.13 In (b), the position of the second pixel column 61 corresponding to the wavelength λ3 is offset from the first pixel column 51 to become x5. x5 is the reference x coordinate WL0 (λ3) in the second pixel column 61. The analyzing unit 70 generates the following first spectrum data based on the first correspondence relationship TL3, and generates the following second spectrum data based on the second correspondence relationship TL4.

[0086] The analysis unit 70 then generates the first spectrum data and the second spectrum data (S03). In step S03, the analysis unit 70 generates the first spectrum data based on the corrected first electrical signal ES1. In addition, the analysis unit 70 generates the second spectrum data based on the corrected second electrical signal ES2. Fig.14As shown, in the first spectral data S1, the analysis unit 70 can obtain the intensity in all bands without saturating the plurality of first pixels 52 in all bands. In contrast, in the second spectral data S2, a band (saturation band Δλ1) in which the plurality of second pixels 62 are saturated is included. Therefore, the analysis unit 70 cannot correctly obtain the intensity in the saturation band Δλ1. When the bands other than the saturation band Δλ1 are set as the unsaturation band Δλ2, the first spectral data S1 has noise overlap in the unsaturation band Δλ2, and the S / N is poor. On the other hand, in the second spectral data S2, the noise does not overlap in the unsaturation band Δλ2, and the analysis unit 70 can obtain high-precision data.

[0087] The analysis unit 70 then performs sensitivity correction and exposure time correction (S04). In the sensitivity correction, the analysis unit 70 generates a function I of the first spectrum data S1 when the first light receiving unit 5 and the second light receiving unit 6 are exposed at the same exposure time. calib_S Function I of (λ)(first function) and second spectrum data S2 calib_L Then, the analysis unit 70 calculates the second function based on the function I calib_S (λ) and function I calib_L (λ) to correct at least one of the first spectral data S1 and the second spectral data S2. calib_S (λ) and function I calib_L (λ) are ideally the same value, and therefore their ratio is ideally 1. However, the light receiving sensitivity of the first light receiving unit 5 and the light receiving sensitivity of the second light receiving unit 6 are not necessarily the same, and the deviation is corrected by sensitivity correction. The sensitivity correction coefficient SR is shown in Formula 1: calib (λ).

[0088] SR calib (λ)=I calib_L (λ) / I calib_S (λ)…(1)

[0089] In the exposure time correction, the analyzing unit 70 corrects at least one of the first spectral data S1 and the second spectral data S2 based on the ratio of the first exposure time ET1 to the second exposure time ET2. The exposure time correction coefficient DRGain is shown by Formula 2.

[0090] DRGain=ET2 / ET1…(2)

[0091] Use sensitivity correction factor SR calib (λ) and the exposure time correction coefficient DRGain, correct the intensity I in the second spectrum data S2 L (λ), the corrected intensity I is shown in Equation 3. L (λ)′.

[0092] I L (λ)′=I L (λ) / (SR calib (λ)×DRGain)…(3)

[0093] In addition, the intensity I in the first spectrum data S1 is corrected. S (λ), the sensitivity correction factor SR calib (λ)×exposure time correction factor DRGain multiplied by I S (λ).

[0094] The analysis unit 70 then corrects the input dependency of the measured light L1 (S05). The measured light L1 is preferably received at the same intensity in the first light receiving unit 5 and the second light receiving unit 6. However, when the measured light L1 is incident on the optical system 3, there is a case where the intensity distribution in the cross section of the measured light L1 is not uniform within the plane. In this case, there is a case where the light intensity of the first pixel column 51 of the light image of a certain wavelength in the imaged spectral image α is different from the light intensity of the second pixel column 61 of the imaged light image. In other words, the first light receiving unit 5 and the second light receiving unit 6 are affected by the input dependency of the measured light L1. In the correction of the input dependency, the analysis unit 70 corrects the above-mentioned difference in light intensity.

[0095] In the correction of the input dependency, the analyzing unit 70 corrects at least one of the first spectral data S1 and the second spectral data S2 based on the ratio of the representative value of the intensity of the first spectral data S1 in the unsaturated wavelength band Δλ2 to the representative value of the intensity of the second spectral data S2 in the unsaturated wavelength band Δλ2. Here, the representative value refers to, for example, Fig.15 As shown, the first area S11 of the first spectral data S1 and the second area S21 of the second spectral data S2. Alternatively, the representative value may be the central value of the intensity of the first spectral data S1 and the central value of the intensity of the second spectral data S2. The range of the intensity after the analysis unit 70 calculates the first area S11 and the second area S21 is set to the range between Imax×0.9 and Imax×0.1 when the value of the intensity saturation in the second spectral data S2 is set to Imax. Since the range between Imax×0.9 and Imax×0.1 is a range with good linear characteristics, the accuracy of correction can be improved. Here, good linear characteristics refers to, for example, Fig.10 A range in which the rate of increase of the linear error in the linear characteristic R1 and the linear characteristic R2 is relatively gentle.

[0096] The range of wavelengths after calculating the first area S11 and the second area S21 is set as the non-saturated band Δλ2. The first area S11 is the range between Imax×0.9 and Imax×0.1 in the first spectral data S1 and the area surrounded by the non-saturated band Δλ2. The second area S21 is the range between Imax×0.9 and Imax×0.1 in the second spectral data S2 and the area surrounded by the non-saturated band Δλ2. The analysis unit 70 corrects at least one of the first spectral data S1 and the second spectral data S2 based on the ratio of the first area S11 to the second area S21, that is, the correction coefficient IR of the input dependence. When using the correction coefficient IR of the input dependence and the sensitivity correction coefficient SR calib (λ) and the exposure time correction coefficient DRGain, correct the intensity I in the second spectrum data S2 L (λ), the corrected intensity I is shown in Equation 4. L (λ)′.

[0097] Strength I L (λ)′=Ⅰ L (λ) / (SR calib (λ)×DRGain×IR)…(4)

[0098] In addition, the intensity I in the first spectrum data S1 is corrected. S (λ), the sensitivity correction factor SR calib (λ)×exposure time correction factor DRGain×input-dependent correction factor IR multiplied by I S (λ).

[0099] The analysis unit 70 then performs stray light correction (S06). As described above, the second spectral data S2 has a superior S / N ratio in the non-saturated band Δλ2 compared to the first spectral data S1. Therefore, in the generation of the spectral data of the measured light L1 described below, by using the second spectral data S2 in the non-saturated band Δλ2, a decrease in detection accuracy can be suppressed. However, in the case where stray light is generated in the second spectral data S2, the stray light is also generated in the spectral data of the measured light L1, and the detection accuracy is reduced. The stray light is generated in the optical system 3, for example, by multiple reflections of a part of the measured light L1 in the lens 33. In the stray light correction, the analysis unit 70 performs a correction for removing the stray light generated in the optical system 3 with respect to the second spectral data S2 in the non-saturated band Δλ2.

[0100] like Fig.16As shown, the stray light L0 is generated in the non-saturated wavelength band Δλ2 of the second spectral data S2. The analyzing unit 70 removes the stray light L0, for example, as described below. The analyzing unit 70 calculates a stray light signal distribution matrix after quantifying the intensity of the stray light L0 in the second spectral data S2. Next, the analyzing unit 70 derives a stray light correction matrix by finding the inverse matrix of the sum of the stray light signal distribution matrix and the unit matrix having the same number of matrices as the stray light signal distribution matrix. Then, the analyzing unit 70 corrects the stray light L0 by matrix multiplication based on the stray light correction matrix.

[0101] Finally, the analysis unit 70 generates spectrum data of the measured light L1 (S07). Fig.17 As shown, the analysis unit 70 combines the data of the saturation band Δλ1 of the first spectral data S1 with the data of the non-saturation band Δλ2 of the second spectral data S2 to generate the spectral data S3 of the measured light L1. For example, the analysis unit 70 divides the corrected first electrical signal ES1 by the first exposure time ET1 with respect to the first spectral data S1, and multiplies the result of the division by the reference exposure time. On the other hand, the analysis unit 70 divides the corrected second electrical signal ES2 by the second exposure time ET2 with respect to the second spectral data S2, and multiplies the result of the division by the reference exposure time. Thus, the analysis unit 70 generates the spectral data S3 of the measured light L1 after combining the scale of the first spectral data S1 with the scale of the second spectral data S2. In the spectral data S3, the intensity in all bands can be obtained without saturation of each pixel in all bands and without noise overlap.

[0102] [Function and Effect]

[0103] In the spectrophotometric device 1, the photodetector 4 receives the spectral image α at the first exposure time ET1 in the first light receiving section 5 and outputs the first electrical signal ES1, and receives the spectral image α at the second exposure time ET2 longer than the first exposure time ET1 in the second light receiving section 6 and outputs the second electrical signal ES2, and the analyzing section 70 generates the first spectral data S1 based on the first electrical signal ES1, and generates the second spectral data S2 based on the second electrical signal ES2. Then, the analyzing section 70 generates the spectral data S3 of the light to be measured L1 based on the first spectral data S1 and the second spectral data S2. Thus, the spectral data S3 of the light to be measured L1 can be generated in a wide dynamic range. Furthermore, in the spectrophotometric device 1, the analyzing section 70 corrects the first electrical signal ES1 using the first correction coefficient k1, and corrects the second electrical signal ES2 using the second correction coefficient k2. Thus, the errors generated in the linear characteristics R1 of the first amplifier 43 and the linear characteristics R2 of the second amplifier 46 can be corrected. Therefore, according to the spectroscopic measurement device 1, it is possible to obtain highly accurate spectrum data S3 of the light to be measured L1.

[0104] In the spectrophotometric device 1, the analyzing unit 70 generates the first spectrum data S1 based on the first correspondence between each of the plurality of first pixel columns 51 and the wavelength in the wavelength axis, and generates the second spectrum data S2 based on the second correspondence between each of the plurality of second pixel columns 61 and the wavelength in the wavelength axis. In the spectrophotometric device 1, there may be a case where the position of the first pixel column 51 of the light image of a certain wavelength in the imaged spectral image α and the position of the second pixel column 61 that images the light image are offset. According to the spectrophotometric device 1, even when such a positional offset occurs, the first spectrum data S1 and the second spectrum data S2 in which such a positional offset is corrected can be acquired.

[0105] In the spectrophotometric device 1, the analyzing unit 70 corrects at least one of the first spectral data S1 and the second spectral data S2 based on the ratio of the representative value of the intensity of the first spectral data S1 to the representative value of the intensity of the second spectral data S2. In the spectrophotometric device 1, there may be a difference between the light intensity of the first pixel column 51 of the light image of a certain wavelength in the imaged spectral image α and the light intensity of the second pixel column 61 that images the light image. According to the spectrophotometric device 1, even when such a difference in light intensity occurs, the first spectral data S1 and the second spectral data S2 in which such a difference in light intensity is corrected can be obtained.

[0106] In the spectrophotometric measurement device 1, the analysis unit 70 corrects the second spectral data S2 to remove the stray light L0 generated in the optical system 3. If only the noise generated in the circuit (for example, the noise generated in the control substrate 8) is considered, the S / N of the second spectral data S2 is higher than the S / N of the first spectral data S1. However, there is a case where the stray light L0 is included in the measured light L1. In this case, the noise caused by the stray light L0 increases by the amount that the second exposure time ET2 is longer than the first exposure time ET1, and the S / N of the second spectral data S2 becomes lower. According to the spectrophotometric measurement device 1, even when the measured light L1 contains the stray light L0, the second spectral data S2 with such stray light L0 removed can be obtained.

[0107] The spectroscopic measurement device 1 further comprises: a bundle optical fiber 2 including a plurality of optical fibers for guiding the measured light L1 to the optical system 3, the bundle optical fiber 2 having a circular incident end face 2a and a strip-shaped exit end face 2b; the plurality of optical fibers including: a plurality of first optical fibers 21 arranged on one side relative to the center of the exit end face 2b on the exit end face 2b; and a plurality of second optical fibers 22 arranged on the other side relative to the center of the exit end face 2b on the exit end face 2b; and on the incident end face 2a, each of the plurality of first optical fibers 21 and each of the plurality of second optical fibers 22 are adjacent to each other in at least one of the circumferential direction and the radial direction. In the spectroscopic measurement device 1, even if the light intensity of the measured light L1 varies on the incident end face 2a of the bundle optical fiber 2, the light intensity of the measured light L1 is suppressed at the exit end face 2b of the bundle optical fiber 2. Therefore, according to the spectroscopic measurement device 1, when focusing on the first pixel column 51 and the second pixel column 61 of the light image of a certain wavelength in the imaging spectral image α, the difference in light intensity between the first pixel column 51 and the second pixel column 61 can be suppressed, and the first spectral data S1 and the second spectral data S2 can be obtained.

[0108] In the spectrophotometry device 1, the photodetector 4 has an electronic shutter function, and the electronic shutter function discharges the first charge Q1 accumulated in each of the plurality of first pixels 52 over a predetermined time (charge discarding time DT) from the beginning of the frame time FT within the frame time FT1 from the start of the transfer of the first charge Q1 from the first vertical transfer unit 41 to the end of the transfer of the first charge Q1 by the first horizontal transfer unit 42, and sets the time other than the predetermined time in the frame time FT as the first exposure time ET1. According to the spectrophotometry device 1, by using the electronic shutter function for the first light receiving unit 5, it is possible to prevent the first pixels 52 in the first light receiving unit 5 from being saturated, and to reliably acquire the first spectrum data S1 in the saturation band Δλ1.

[0109] In the spectrophotometry device 1, the analyzing unit 70 generates a first function of the first spectrum data S1 and a second function of the second spectrum data S2 when the first light receiving unit 5 and the second light receiving unit 6 are exposed at the same exposure time, and corrects at least one of the first spectrum data S1 and the second spectrum data S2 based on the ratio of the first function to the second function. In the spectrophotometry device 1, the light receiving sensitivity of the first light receiving unit 5 and the light receiving sensitivity of the second light receiving unit 6 are not necessarily the same. According to the spectrophotometry device 1, even when a shift in the light receiving sensitivity occurs, the first spectrum data S1 and the second spectrum data S2 in which such a shift in the light receiving sensitivity is corrected can be obtained.

[0110] In the spectrophotometer 1, the analyzing unit 70 corrects at least one of the first spectral data S1 and the second spectral data S2 based on the ratio of the first exposure time ET1 to the second exposure time ET2. According to the spectrophotometer 1, the first spectral data S1 and the second spectral data S2 in which the influence of the difference in exposure time on the light intensity is corrected can be obtained.

[0111] In the spectrophotometric device 1, the photodetector 4 receives the spectrophotometric image α at the first exposure time ET1 in the first light receiving section 5 and outputs the first electric signal ES1, and receives the spectrophotometric image α at the second exposure time ET2 longer than the first exposure time ET1 in the second light receiving section 6 and outputs the second electric signal ES2. Then, the storage section 7 stores the first correction coefficient k1 for correcting the first electric signal ES1 and the second correction coefficient k2 for correcting the second electric signal ES2. Therefore, when the spectrum data S3 of the measured light L1 is generated based on the first electric signal ES1 and the second electric signal ES2, by correcting the first electric signal ES1 using the first correction coefficient k1 and correcting the second electric signal ES2 using the second correction coefficient k2, errors generated in the linear characteristics R1 of the first amplifier 43 and the linear characteristics R2 of the second amplifier 46 can be corrected. Therefore, according to the spectrophotometric device 1, the spectrum data S3 of the measured light L1 with high accuracy can be obtained.

[0112] According to the spectroscopic measurement method, for the same reason as that of the spectroscopic measurement device 1 , it is possible to obtain high-precision spectrum data S3 of the light to be measured L1 .

[0113] [Modifications]

[0114] The present invention is not limited to the above-mentioned embodiment. When the light detector 4 uses the electronic shutter function and sets the first exposure time ET1 to a time shorter than the one frame time FT, Fig.18 As shown in FIG. 1 , the longer the charge discarding time DT is, the lower the intensity of the first electrical signal ES1 is. Fig.18 In the figure, the horizontal axis shows the charge discarding time DT, and the vertical axis shows the intensity of the first electric signal ES1. Here, when the intensity of the first electric signal ES1 when the charge discarding time DT is 0ms is set to 100%, the intensity of the first electric signal ES1 is displayed in % according to the charge discarding time DT. When the charge discarding time DT is 0ms, the photodetector 4 does not operate the electronic shutter. When the charge discarding time DT is around 0.1ms, the intensity of the first electric signal ES1 decreases sharply. That is, by setting the state where the electronic shutter is not operated from the photodetector 4 to the state where it is operated, the first electric signal ES1 decreases sharply. When the charge discarding time DT is from around 0.2ms to around 8.3ms, the first electric signal ES1 decreases linearly inversely proportional to the charge discarding time DT. During this period, when the photodetector 4 operates the electronic shutter, as shown in FIG. Figure 7 As described above, the region 5a is trapezoidal. When the charge discarding time DT is in the range of about 8.4 ms to about 10 ms, the first electrical signal ES1 decreases nonlinearly in inverse proportion to the charge discarding time DT. During this period, when the photodetector 4 operates the electronic shutter, as shown in FIG. Figure 8 As described above, the region 5a is triangular in shape.

[0115] like Fig.19 As shown, the analysis unit 70 stores the table TL5 that establishes the correspondence between the third correction coefficient k3 and the charge discarding time DT in the storage unit 7. As described above, when the electronic shutter function is used, the intensity of the first electrical signal ES1 decreases according to the length of the charge discarding time DT. If the intensity of the first electrical signal ES1 decreases linearly, it may decrease nonlinearly or rapidly. Therefore, since the linear characteristic R1 of the first amplifier 43 changes, it is difficult to make the linear characteristic R1 consistent with the reference linear characteristic R0 in the first correction coefficient k1 when performing the linear correction (S01) of the first amplifier 43. Therefore, based on the decreasing trend of the intensity of the first electrical signal ES1 corresponding to the charge discarding time DT, the third correction coefficient k3 is calculated for each charge discarding time DT through actual measurement or simulation. The analysis unit 70 stores the calculated result as the table TL5 of the third correction coefficient k3 corresponding to the charge discarding time DT. The analysis unit 70 uses the third correction coefficient k3 instead of the first correction coefficient k1 to correct the first electrical signal ES1. Thus, even when the electronic shutter function is used, the linear characteristic R1 of the first amplifier 43 is consistent with the reference linear characteristic R0. Thus, the first spectrum data S1 in which the error generated in the linear characteristic R1 of the first amplifier 43 is corrected can be obtained. In addition, the analysis unit 70 may store the third correction coefficient k3 corresponding to the first exposure time ET1 as the table TL5. Alternatively, the analysis unit 70 may store the third correction coefficient k3 corresponding to the converted intensity of the first electrical signal ES1 as the table TL5.

[0116] When the photodetector 4 uses the electronic shutter function and sets the first exposure time ET1 to a time shorter than the one frame time FT, only the first charge Q1 accumulated in a part of the first pixel 52 may be vertically and horizontally transferred. Figure 8 As shown in FIG. 1 , when the region 5a is triangular, the first charge Q1 transferred to the first horizontal transfer section 42 at the end of the exposure time t6 is only the charge accumulated in each first pixel 52 on the first horizontal transfer section 42 side. Fig.12In the embodiment, only the first charge Q1 accumulated in the first pixel 52 of the image of the imaging wavelength λ2 and the first charge Q1 stored in the first pixel 52 close to the first horizontal transfer unit 42 is transmitted. The first pixel 52 close to the first horizontal transfer unit 42 is offset from the reference x-coordinate WL0 (λ2). Therefore, the first electric signal ES1 corresponding to the wavelength λ2 is not transmitted from the x-coordinate x2 of the reference x-coordinate WL0 (λ2). That is, the first correspondence relationship when the electronic shutter function is used changes from the first correspondence relationship when the electronic shutter function is not used.

[0117] Therefore, the first corresponding relationship corresponding to the length of the first exposure time ET1 is measured in advance, and the analysis unit 70 is as follows: Fig. 20 As shown in FIG. 1 , the measurement result is stored in the storage unit 7 as a table TL6 of the first correspondence relationship after correction. Fig. 20 In the case where the first exposure time ET1 is set to t32, as shown in FIG. Figure 8 As shown, the area 5a becomes a triangle. In this case, the position of the first pixel column 51 corresponding to the wavelength λ2 becomes x4 taking into account the deviation from the reference x coordinate WL0 (λ2), rather than x2 corresponding to the reference x coordinate WL0 (λ2). The analysis unit 70 generates the first spectral data S1 based on the table TL6 of the corrected first correspondence. Thus, the first spectral data S1 in which the deviation between the first correspondence when the electronic shutter function is used and the correspondence when the electronic shutter function is not used is corrected can be obtained. In addition, the analysis unit 70 may also store the first correspondence corresponding to the length of the charge discard time DT as the table TL6. That is, the analysis unit 70 may also generate the first spectral data S1 based on the first correspondence corresponding to at least one of the charge discard time DT and the first exposure time ET1.

[0118] The analyzing unit 70 may calculate the position on the wavelength axis of the first pixel row 51 corresponding to each wavelength using a mathematical formula instead of the corrected first correspondence table TL6.

[0119] WL(t,λ)=WL0(λ)+∑y{w(y,t)×WL error (y, λ)}…(5)

[0120] Formula 5 assumes that the position of each first pixel 52 in the vertical direction is y, the charge discarding time DT is t, and the weight of the first charge Q1 transferred from each first pixel 52 is modeled by w(y, t). In addition, Formula 5 assumes that the deformation amount of the image of each wavelength obtained by optical simulation is WL error (y, λ), and the reference x coordinate is set to WL0(λ). Thus, by calculating the weight w(y, t) and the deformation amount WL0 for each first pixel 52, errorThe multiplication result of (y, λ) is used to calculate the offset from the reference x-coordinate WL0 (λ), and the position of the first pixel column 51 on the wavelength axis can be calculated with high accuracy.

[0121] In the above-mentioned embodiment and the above-mentioned modification, the case where the photodetector 4 uses the electronic shutter function to set the first exposure time ET1 to a time shorter than the one frame time FT is described. Similarly, the photodetector 4 may also use the electronic shutter function to set the second exposure time ET2 to a time shorter than the one frame time FT. However, in this case, the photodetector 4 needs to make the first exposure time ET1 shorter than the second exposure time ET2. When the second exposure time ET2 is set using the electronic shutter function, the intensity of the second electrical signal ES2 decreases according to the charge discarding time DT. Therefore, the analysis unit 70 may store the fourth correction coefficient k4 corresponding to the charge discarding time DT, and use the fourth correction coefficient k4 instead of the second correction coefficient k2 to correct the second electrical signal ES2. In addition, the second correspondence when the electronic shutter function is used changes according to the second correspondence when the electronic shutter function is not used. Therefore, the second correspondence corresponding to the length of the second exposure time ET2 is measured in advance, and the analysis unit 70 may also store the measured result as the corrected second correspondence. Then, the analyzing unit 70 may generate the second spectrum data S2 based on the corrected second correspondence relationship.

[0122] The analyzing unit 70 may calculate the ratio of the third correction coefficient k3 to the fourth correction coefficient k4, and use the ratio of the third correction coefficient k3 to the fourth correction coefficient k4 to correct the intensity of the first spectrum data S1 or the intensity of the second spectrum data S2. L (λ), the corrected intensity I is shown in Equation 6. L (λ)′.

[0123] Strength I L (λ)′=I L (λ) / {SR calib (λ)×DRGain×(k4 / k3)}…(6)

[0124] The photodetector 4 may have an anti-blooming function. By exposing the second light receiving unit 6 during the second exposure time ET2, the amount of the second charge Q2 accumulated in each second pixel 62 may exceed a specific amount. As a result, there may be a phenomenon (blooming) in which the excess charge overflows to the adjacent second pixel 62. When blooming occurs, Fig.21As shown, the second spectrum data S2 becomes data S20 affected by halo. After the analysis unit 70 generates the spectrum data S3 of the measured light L1, it is not possible to accurately combine the first spectrum data S1 with the data S20 affected by halo. Therefore, for example, the light detector 4 can also prevent halo by providing a drain in the second light receiving unit 6 and discarding the remaining charge. In this case, the light detector 4 can also use the anti-halo function for the charge amount of the second charge Q2 that is less than the value obtained by multiplying the maximum value of DRGain in Formula 2 (for example, 100 times) by the above-mentioned specific amount.

[0125] like Fig. 22 As shown, the light diffusion section 11 may also be arranged at the front section of the bundle optical fiber 2. The light diffusion section 11 guides the measured light L1 to the incident end face 2a in a diffused state. The light diffusion section 11 is, for example, a diffusion plate. Since the measured light L1 diffused by the light diffusion section 11 is incident on the incident end face 2a of the bundle optical fiber 2, the deviation of the light intensity of the measured light L1 is suppressed on the incident end face 2a of the bundle optical fiber 2. In addition, the deviation of the light intensity of the measured light L1 is also suppressed on the output end face 2b of the bundle optical fiber 2. Therefore, when focusing on the first pixel column 51 and the second pixel column 61 of the light image of a certain wavelength in the imaging spectral image α, the difference between the light intensity of the first pixel column 51 and the light intensity of the second pixel column 61 can be suppressed, and the first spectral data S1 and the second spectral data S2 can be obtained.

[0126] The optical system 3 is not limited to the Dyson optical system, but may be other optical systems (such as the Chernitner optical system). The diffraction grating 32 may also be a transmission type diffraction grating. The photodetector 4 is not limited to the full frame transfer type CCD image sensor, but may be other types of CCD image sensors such as interline type or frame transfer type. The photodetector 4 may perform vertical transmission and horizontal transmission by adding each n pixels (n is an integer of 2 to 127) instead of FVB. Alternatively, the photodetector 4 may also vertically transmit charge for each pixel. The computer device 20 may be a device incorporated into the spectrometer 10 instead of a personal computer, etc. The computer device 20 may also store the correction coefficient instead of the storage unit 7. In this case, the computer device 20 may also generate the spectrum data of the measured light L1 after correcting the data obtained from the photodetector 4. The output end face 2b of the bundle optical fiber 2 may not be in a long strip shape. For example, the output end face 2b may be in a circular shape. The bundle optical fiber 2 may include only one optical fiber. For example, the bundled optical fiber 2 may include any of a first optical fiber 21 , a second optical fiber 22 , a third optical fiber 23 , and a fourth optical fiber 24 .

[0127] Explanation of symbols

[0128] 1…spectrometric measuring device, 2…bundle optical fiber, 2a…incident end face, 2b…exit end face, 3…optical system, 4…photodetector, 5…first light receiving unit, 6…second light receiving unit, 7…storage unit, 8…control substrate, 11…light diffusion unit, 21…first optical fiber, 22…second optical fiber, 41…first vertical transmission unit, 42…first horizontal transmission unit, 43…first amplifier, 44…second vertical transmission unit, 45…second horizontal transmission unit, 46…second amplifier, 51…first pixel column, 52…first pixel, 61…second pixel column, 62…first 2 pixels, 70…analysis unit, A…wavelength axis, ES1…first electrical signal, ES2…second electrical signal, ET1…first exposure time, ET2…second exposure time, FT…1 frame time, k1…first correction coefficient, k2…second correction coefficient, k3…third correction coefficient, L0…stray light, L1…measured light, Q1…first charge, Q2…second charge, R1, R2…linear characteristics, S1…first spectral data, S2…second spectral data, S3…spectral data, α…spectral image, Δλ1…saturated band, Δλ2…unsaturated band.

Claims

1. A spectrophotometric measuring device, wherein: have: an optical system for splitting the light to be measured; a photodetector that detects a spectroscopic image of the light to be measured that is dispersed by the optical system; and an analyzing unit that generates spectrum data of the light to be measured, The light detector has: a first light receiving unit having a plurality of first pixel columns arranged in a horizontal direction parallel to the wavelength axis of the spectral image, wherein the plurality of first pixel columns respectively include a plurality of first pixels arranged in a vertical direction perpendicular to the wavelength axis; a second light receiving unit, which is arranged side by side with the first light receiving unit in the vertical direction and has a plurality of second pixel columns arranged in the horizontal direction, wherein the plurality of second pixel columns respectively include a plurality of second pixels arranged in the vertical direction; a first vertical transfer section for transferring first charges accumulated in each of the plurality of first pixels by receiving the split image in the first light receiving section for a first exposure time, along the vertical direction for each of the plurality of first pixel columns; a first horizontal transfer section that transfers the first charges transferred by the first vertical transfer section along the horizontal direction; a first amplifier that outputs a first electrical signal corresponding to the amount of the first charge transferred by the first horizontal transfer section; a second vertical transfer section for transferring, along the vertical direction for each of the plurality of second pixel columns, second charges accumulated in each of the plurality of second pixels by receiving the split image in the second light receiving section for a second exposure time longer than the first exposure time; a second horizontal transfer section that transfers the second charges transferred by the second vertical transfer section along the horizontal direction; and a second amplifier that outputs a second electrical signal corresponding to the amount of the second charge transferred by the second horizontal transfer section, The analysis unit, storing a first correction coefficient for correcting the first electrical signal in such a way that the linear characteristic of the first amplifier coincides with a reference linear characteristic; storing a second correction coefficient for correcting the second electrical signal in such a way that the linear characteristic of the second amplifier coincides with the reference linear characteristic; Correcting the first electrical signal using the first correction coefficient; Correcting the second electrical signal using the second correction coefficient; generating first spectrum data based on the corrected first electrical signal; generating second spectrum data based on the corrected second electrical signal; The spectrum data of the light to be measured is generated based on the first spectrum data and the second spectrum data.

2. The spectrophotometer according to claim 1, wherein: The analysis unit, generating the first spectrum data based on a first correspondence between each of the plurality of first pixel columns and a wavelength in the wavelength axis; The second spectrum data is generated based on a second correspondence between each of the plurality of second pixel columns and a wavelength in the wavelength axis.

3. The spectrophotometer according to claim 1 or 2, wherein: The analyzing unit corrects at least one of the first spectral data and the second spectral data based on a ratio between a representative value of the intensity of the first spectral data and a representative value of the intensity of the second spectral data.

4. The spectrophotometer according to any one of claims 1 to 3, wherein: The analyzing unit performs correction on the second spectrum data to remove stray light generated in the optical system.

5. The spectrophotometer according to any one of claims 1 to 4, wherein: The optical fiber further comprises a bundle optical fiber including a plurality of optical fibers for guiding the light to be measured to the optical system, the bundle optical fiber having a circular incident end face and a long strip-shaped emission end face, The plurality of optical fibers include: a plurality of first optical fibers arranged on one side of the output end face relative to the center of the output end face; and a plurality of second optical fibers arranged on the output end face relative to the center of the output end face, On the incident end face, each of the plurality of first optical fibers and each of the plurality of second optical fibers are adjacent to each other in at least one of a circumferential direction and a radial direction.

6. The spectrophotometer according to any one of claims 1 to 5, wherein: Also available: a bundled optical fiber including a plurality of optical fibers for guiding the light to be measured toward the optical system; and The light diffusion unit is disposed at a front stage of the bundle optical fiber and guides the light to be measured toward an incident end face of the bundle optical fiber in a state where the light to be measured is diffused.

7. The spectrophotometer according to any one of claims 1 to 6, wherein: The photodetector has an electronic shutter function for discharging the first charges accumulated in each of the plurality of first pixels over a predetermined time from the beginning of the one frame time during a one frame time from when the first vertical transfer section starts transferring the first charges to when the first horizontal transfer section ends transferring the first charges, thereby setting the time other than the predetermined time in the one frame time as the first exposure time. The analysis unit, When the electronic shutter function is used, a third correction coefficient for correcting the first electrical signal in such a way that the linear characteristic of the first amplifier coincides with the reference linear characteristic is associated with the predetermined time and stored; The first electrical signal is corrected using the third correction coefficient.

8. The spectrophotometer according to claim 2, wherein: The photodetector has an electronic shutter function for discharging the first charges accumulated in each of the plurality of first pixels over a predetermined time from the beginning of the one frame time during a one frame time from when the first vertical transfer section starts transferring the first charges to when the first horizontal transfer section ends transferring the first charges, thereby setting the time other than the predetermined time in the one frame time as the first exposure time. The analyzing unit generates the first spectrum data based on the first correspondence relationship corresponding to at least one of the predetermined time and the first exposure time.

9. The spectrophotometer according to any one of claims 1 to 6, wherein: The photodetector has an electronic shutter function of setting the time except the prescribed time in the 1 frame time as the first exposure time by discharging the first charges accumulated in each of the plurality of first pixels over a prescribed time from the beginning of the 1 frame time within a 1 frame time from the start of the transfer of the first charges by the first vertical transfer section to the end of the transfer of the first charges by the first horizontal transfer section.

10. The spectrophotometer according to any one of claims 1 to 9, wherein: The analysis unit, When the first light receiving unit and the second light receiving unit are exposed for the same exposure time, a first function of the first spectral data and a second function of the second spectral data are generated, and based on the ratio of the first function to the second function, at least one of the first spectral data and the second spectral data is corrected.

11. The spectrophotometer according to any one of claims 1 to 10, wherein: The analyzing unit corrects at least one of the first spectral data and the second spectral data based on a ratio between the first exposure time and the second exposure time.

12. A spectrophotometric measuring device, wherein: have: an optical system for splitting the light to be measured; a photodetector that detects a spectroscopic image of the light to be measured that is dispersed by the optical system; and Storage Department, The light detector has: a first light receiving unit having a plurality of first pixel columns arranged in a horizontal direction parallel to the wavelength axis of the spectral image, wherein the plurality of first pixel columns respectively include a plurality of first pixels arranged in a vertical direction perpendicular to the wavelength axis; a second light receiving unit, which is arranged side by side with the first light receiving unit in the vertical direction and has a plurality of second pixel columns arranged in the horizontal direction, wherein the plurality of second pixel columns respectively include a plurality of second pixels arranged in the vertical direction; a first vertical transfer section for transferring first charges accumulated in each of the plurality of first pixels by receiving the split image in the first light receiving section for a first exposure time, along the vertical direction for each of the plurality of first pixel columns; a first horizontal transfer section that transfers the first charges transferred by the first vertical transfer section along the horizontal direction; a first amplifier that outputs a first electrical signal corresponding to the amount of the first charge transferred by the first horizontal transfer section; a second vertical transfer section for transferring, along the vertical direction for each of the plurality of second pixel columns, second charges accumulated in each of the plurality of second pixels by receiving the split image in the second light receiving section for a second exposure time longer than the first exposure time; a second horizontal transfer section that transfers the second charges transferred by the second vertical transfer section along the horizontal direction; and a second amplifier that outputs a second electrical signal corresponding to the amount of the second charge transferred by the second horizontal transfer section, the storage unit, storing a first correction coefficient for correcting the first electrical signal in such a way that the linear characteristic of the first amplifier coincides with a reference linear characteristic; A second correction coefficient for correcting the second electrical signal so that the linear characteristic of the second amplifier coincides with the reference linear characteristic is stored.

13. A spectrophotometric method, wherein: It is a spectrophotometric method using a spectrophotometric device. The spectrophotometer comprises: an optical system for splitting the light to be measured; a photodetector that detects a spectroscopic image of the light to be measured that is dispersed by the optical system; and an analyzing unit that generates spectrum data of the light to be measured, The light detector has: a first light receiving unit having a plurality of first pixel columns arranged in a horizontal direction parallel to the wavelength axis of the spectral image, wherein the plurality of first pixel columns respectively include a plurality of first pixels arranged in a vertical direction perpendicular to the wavelength axis; a second light receiving unit, which is arranged side by side with the first light receiving unit in the vertical direction and has a plurality of second pixel columns arranged in the horizontal direction, wherein the plurality of second pixel columns respectively include a plurality of second pixels arranged in the vertical direction; a first vertical transfer section for transferring first charges accumulated in each of the plurality of first pixels by receiving the split image in the first light receiving section for a first exposure time, along the vertical direction for each of the plurality of first pixel columns; a first horizontal transfer section that transfers the first charges transferred by the first vertical transfer section along the horizontal direction; a first amplifier that outputs a first electrical signal corresponding to the amount of the first charge transferred by the first horizontal transfer section; a second vertical transfer section for transferring second charges accumulated in each of the plurality of second pixels by receiving the split image in the second light receiving section for a second exposure time longer than the first exposure time, along the vertical direction for each of the plurality of second pixel columns; a second horizontal transfer section that transfers the second charges transferred by the second vertical transfer section along the horizontal direction; and a second amplifier that outputs a second electrical signal corresponding to the amount of the second charge transferred by the second horizontal transfer section, The spectrophotometric method comprises: The step of correcting the first electrical signal in such a way that the linear characteristic of the first amplifier is consistent with a reference linear characteristic, and correcting the second electrical signal in such a way that the linear characteristic of the second amplifier is consistent with the reference linear characteristic; The step of generating first spectrum data based on the corrected first electrical signal and generating second spectrum data based on the corrected second electrical signal; and A step of generating the spectrum data of the light to be measured based on the first spectrum data and the second spectrum data.

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