Spectroscopic device, Raman spectroscopic measurement device, and spectroscopic method

Abstract

A spectroscopic device (5) for receiving light (L1) wavelength-decomposed in a predetermined direction by a spectroscopic optical system (4) including a spectroscopic element and acquiring spectroscopic spectral data of the light (L1), the spectroscopic device (5) being provided with: a CCD-type imaging element (9) for imaging the light (L1); a liquid crystal display device having a pixel section (11) in which a plurality of pixels (21) are arranged in a row direction along a wavelength decomposition direction of light (L1) and in a column direction perpendicular to the row direction, accumulation sections (12) which are arranged in columns at ends of the pixel section (11) in the column direction and which accumulate charges generated in each column of pixels (21), and output and accumulation sections (12) a read-out unit (13) for reading out an electrical signal for each column corresponding to the magnitude of the electric charge accumulated in the column; a semiconductor element (10) that converts the electrical signal of each column into a digital signal and outputs the digital signal; and a generation unit (15) that generates spectral data (32) on the basis of the digital signal.

Description

Technical Field

[0001] The present disclosure relates to a spectroscopic device, a Raman spectrometric measurement device and a spectroscopic method. Background Art

[0002] As an existing spectroscopic device, there is a spectroscopic device described in Patent Document 1, for example. This existing spectroscopic device is a so-called Raman spectroscopic device. The spectroscopic device includes: a mechanism for linearly irradiating excitation light; a movable stage on which a sample is placed; an objective lens that focuses Raman light from an area irradiated with excitation light; a narrow slot that is provided at an imaging position of the Raman light; a spectrometer that disperses light passing through the narrow slot; a CCD detector that detects a Raman spectrum image; and a control device that controls positioning measurement by synchronizing the movable stage with the CCD detector. Prior art literature Patent Literature

[0003] Patent Document 1: Japanese Patent Application Publication No. 2016-180732 Summary of the invention The problem the invention is intended to solve

[0004] In the field of spectrometry such as Raman spectroscopy, fluorescence spectroscopy, and plasma spectroscopy, vertical binning of CCD image sensors is used when obtaining spectroscopic spectrum data in order to improve the signal-to-noise ratio. Vertical binning in CCD image sensors divides the charges generated in each pixel into multiple poles and adds them together. In CCD image sensors, read noise is only generated in the final amplifier and does not increase during the vertical binning process. Therefore, the more the number of vertical binning stages increases, the higher the signal-to-noise ratio can be.

[0005] As image sensors, CMOS image sensors are also known in addition to CCDs. However, at present, the popularity of CMOS image sensors has not progressed in the field of spectrometry. In CMOS image sensors, an amplifier is configured in each pixel to convert charge into voltage for each pixel. In the case of vertical binning in existing CMOS image sensors, the more the number of vertical binning stages increases, the more the readout noise is accumulated, so there is a problem that the signal S / N ratio is lower than when using a CCD image sensor.

[0006] The present disclosure has been made to solve the above-mentioned problems, and an object of the present disclosure is to provide a spectroscopic device, a Raman spectrometry device, and a spectroscopic method that can acquire spectroscopic spectrum data with an excellent SN ratio. Technical means of solving problems

[0007] The gist of a Raman spectrometry device and a spectroscopic method according to one embodiment of the present disclosure is as shown in the following [1] to

[10] .

[0008] [1] A spectroscopic device that receives light decomposed by wavelength in a specified direction through a spectroscopic optical system including a spectroscopic element and obtains spectroscopic spectrum data of the light, and comprises: a CCD-type imaging element having a pixel portion that arranges a plurality of pixels in a row direction along the wavelength decomposition direction of the light and in a column direction perpendicular to the row direction, a storage portion that is arranged in columns at the ends of the column direction of the pixel portion to store charges generated in each column of pixels, and a readout portion that outputs an electrical signal of each column corresponding to the size of the charges stored in the storage portion; a semiconductor element that converts the electrical signal of each column output from the readout portion into a digital signal and outputs the digital signal; and a generating portion that generates the spectroscopic spectrum data based on the digital signal output from the semiconductor element.

[0009] In the spectroscopic device, after receiving the light decomposed by wavelength through a plurality of pixels arranged in the row direction and the column direction and accumulating the charge generated in each column pixel, the electrical signal of each column corresponding to the size of the charge is output. Since these processes are performed by a CCD type imaging element, the increase of the readout noise when reading the charge generated in each column pixel can be avoided. In addition, when outputting a digital signal based on the electrical signal of each column, the readout becomes faster than the case of setting a horizontal transfer circuit, and the noise caused by heat is also suppressed. Therefore, in the spectroscopic device, the spectroscopic spectrum data can be obtained with an excellent SN ratio.

[0010] [2] A spectroscopic device as described in [1], wherein the imaging element comprises: a first pixel unit and a second pixel unit, which are divided along the column direction; a first storage unit and a second storage unit, wherein the first storage unit is arranged at the end of the first pixel unit in the column direction by column to store the charges generated in the pixels of each column, and the second storage unit is arranged at the end of the second pixel unit in the column direction by column to store the charges generated in the pixels of each column; and a first readout unit and a second readout unit, wherein the first readout unit outputs a first electric signal corresponding to the size of the charges accumulated in the first storage unit, and the second readout unit outputs a second electric signal corresponding to the size of the charges accumulated in the second storage unit; and the semiconductor element comprises: a first conversion unit, which converts the first electric signal of each column output from the first readout unit into a digital signal and outputs it; and a second conversion unit, which converts the second electric signal of each column output from the second readout unit into a digital signal and outputs it. In this case, the first pixel unit and the second pixel unit can be used separately according to the form of the spectral spectrum image. Therefore, the spectral spectrum data of various lights can be acquired with a good SN ratio.

[0011] [3] A spectroscopic device as described in [2], wherein the first exposure time of each pixel belonging to the first pixel unit is shorter than the second exposure time of each pixel belonging to the second pixel unit. According to this structure, for example, a spectroscopic spectrum image of light whose intensity varies depending on the wavelength can be obtained at different exposure times in the first pixel unit and the second pixel unit. By combining the saturated band of the spectroscopic spectrum data obtained at the first pixel unit with a shorter exposure time and the non-saturated band of the spectroscopic spectrum data obtained at the second pixel unit with a longer exposure time, spectroscopic spectrum data with a good SN ratio can be obtained in a higher dynamic range.

[0012] [4] The spectroscopic device as described in [3], wherein during the period when the second pixel unit acquires image data of one frame, the first pixel unit acquires image data of a plurality of frames. In this case, even when different exposure times are set in the first pixel unit and the second pixel unit, the readout noise of each column of pixels can be made consistent between the first pixel unit and the second pixel unit. Therefore, the SN ratio of the spectroscopic spectrum data can be stably improved.

[0013] [5] A spectroscopic device as described in [1], wherein the imaging element comprises: a first pixel unit and a second pixel unit divided along the row direction; a first storage unit and a second storage unit, wherein the first storage unit is arranged at the end of the first pixel unit in the column direction by column to store the charge generated in each column of pixels, and the second storage unit is arranged at the end of the second pixel unit in the column direction by column to store the charge generated in each column of pixels; and a first readout unit and a second readout unit, wherein the first readout unit outputs a first electrical signal corresponding to the magnitude of the charge accumulated in the first storage unit, and the second readout unit outputs a second electrical signal corresponding to the magnitude of the charge accumulated in the second storage unit. In this case, the first pixel unit and the second pixel unit can be used separately according to the manner of spectroscopic spectral imaging. Therefore, spectroscopic spectrum data of various lights can be acquired with a good SN ratio.

[0014] [6] The spectroscopic device as described in [5], wherein the first readout section outputs the first electrical signal of each column when the charges generated in the pixels of the first number of rows are accumulated in the first accumulation section; and the second readout section outputs the second electrical signal of each column when the charges generated in the pixels of the second number of rows less than the first number of rows are accumulated in the second accumulation section. In this case, spectroscopic spectrum data with a good SN ratio can be obtained with a high dynamic range while keeping the exposure time of each pixel belonging to the first pixel section equal to the exposure time of each pixel belonging to the second pixel section.

[0015] [7] The spectroscopic device according to any one of [1] to [6], further comprising: an analysis unit that analyzes the spectroscopic spectrum data. In this case, the spectroscopic device is provided with a function of analyzing the spectroscopic spectrum data, thereby improving convenience.

[0016] [8] The spectroscopic device according to any one of [1] to [7], further comprising: the spectroscopic optical system including the spectroscopic element. In this case, the spectroscopic device has a function of decomposing light by wavelength, thereby improving convenience.

[0017] [9] A Raman spectrometry device comprising: a spectrometer as described in any one of [1] to [8]; a light source unit that generates light to be irradiated to a sample; and a light guiding optical system that guides Raman scattered light generated by irradiating the sample with the light to the spectrometer.

[0018] In the Raman spectrometer, after receiving wavelength-decomposed Raman scattered light through a plurality of pixels arranged in the row direction and the column direction, and accumulating the charge generated in each column pixel, an electrical signal of each column corresponding to the size of the charge is output. Since these processes are performed by a CCD type imaging element, an increase in readout noise when reading out the charge generated in each column pixel can be avoided. In addition, when outputting a digital signal based on the electrical signal of each column, the readout becomes faster than when a horizontal transfer circuit is provided, and noise caused by heat is also suppressed. Therefore, in the Raman spectrometer, spectroscopic spectrum data can be obtained with an excellent SN ratio.

[0019]

[10] A spectroscopic method, which is a method for receiving light decomposed by wavelength along a specified direction and obtaining spectroscopic spectrum data of the light, and comprises: a light receiving step, in which a plurality of pixels arranged in a row direction along the wavelength decomposition direction and in a column direction perpendicular to the row direction receive the light decomposed by wavelength; an accumulation step, in which charges generated in each column of pixels are accumulated; a readout step, in which an electrical signal of each column corresponding to the size of the accumulated charges is output; a conversion step, in which the electrical signal of each column is converted into a digital signal and outputted; and a generation step, in which the spectroscopic spectrum data is generated based on the digital signal.

[0020] In this spectroscopic method, after receiving the light decomposed by wavelength through a plurality of pixels arranged in the row direction and the column direction and accumulating the charge generated in each column of pixels, the electrical signal of each column corresponding to the size of the charge is output. Thus, the increase of the readout noise when reading the charge generated in each column of pixels can be avoided. In addition, when outputting the digital signal based on the electrical signal of each column, the readout becomes high-speed and the noise caused by heat is also suppressed. Therefore, in this spectroscopic method, the spectroscopic spectrum data can be obtained with an excellent SN ratio. Effects of the Invention

[0021] According to the present disclosure, spectroscopic spectrum data can be acquired with an excellent SN ratio. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a block diagram showing the structure of a Raman spectrometer according to one embodiment of the present disclosure. Figure 2 It is a schematic diagram showing an example of a pixel portion. Figure 3 This is a schematic graph showing an example of spectroscopic spectrum data acquired by a spectroscopic device. Figure 4 : is a diagram showing the structure of an imaging sensor. Figure 5 : is a diagram showing the structure of an imaging sensor. Figure 6 It is a schematic cross-sectional view showing the peripheral structure of the reservoir. Figure 7 A diagram showing the structure of a semiconductor element. Figure 8 A diagram showing the structure of a semiconductor element. Fig. 9 It is a schematic diagram showing the relationship between the exposure time of each pixel belonging to the first imaging unit and the exposure time of each pixel belonging to the second imaging unit. Fig.10 1 is a flowchart showing a spectroscopic method according to an embodiment of the present disclosure. Fig.11 Schematic diagram showing a pixel unit of a spectroscopic device according to a modified example. Fig.12 This is a graph showing an example of the spectrum of light incident on the spectroscopic device according to the modification. Fig.13 This is a graph showing an example of the first spectrum data and the second spectrum data acquired by the spectroscopic device according to the modification. Fig.14 It is shown from Fig.13 Graph of an example of spectral data generated by the first spectral data and the second spectral data shown. Fig.15 1 is a schematic diagram showing a state of forming a spectroscopic spectrum image in a spectroscopic device according to a modification. DETAILED DESCRIPTION

[0023] Hereinafter, preferred embodiments of a spectroscopic device, a Raman spectrometry device, and a spectroscopic method according to one aspect of the present disclosure will be described in detail with reference to the drawings.

[0024] Figure 11 is a block diagram showing the structure of a Raman spectrometer according to an embodiment of the present disclosure. The Raman spectrometer 1 is a device for measuring the physical properties of a sample S using Raman scattered light Lr. In the Raman spectrometer 1, light L1 from a light source unit 2 is irradiated onto the sample S, and the Raman scattered light Lr generated by the interaction between the light L1 and the sample S is detected by a spectrometer 5, and spectroscopic spectrum data of the Raman scattered light Lr is obtained. By analyzing the spectroscopic spectrum data obtained by the spectrometer 5 with a computer 6, various physical properties of the sample S, such as the molecular structure, crystallinity, orientation, and distortion amount, can be evaluated. Examples of the sample S include semiconductor materials, polymers, cells, and pharmaceuticals.

[0025] Raman spectrometry device 1 Figure 1 As shown, the Raman spectrometer 1 includes a light source unit 2, a light guide optical system 3, a spectroscopic optical system 4, a spectroscopic device 5, a computer 6, and a display unit 7. In the following description, for convenience of description, the light incident on the spectroscopic device 5 via the spectroscopic optical system 4 and the Raman scattered light Lr are sometimes referred to as light L1. In the spectroscopic device 5 incorporated in the Raman spectrometry device 1, the light L1 refers to the Raman scattered light Lr.

[0026] The light source unit 2 is a part that generates the light L0 irradiated to the sample S. As the light source constituting the light source unit 2, for example, a laser light source, a light emitting diode, etc., which are excitation light sources for Raman spectroscopy, can be used. The light guide optical system 3 is a part that guides the Raman scattered light Lr generated by irradiating the sample S with the light L0 to the spectroscopic device 5. The light guide optical system 3 is configured to include, for example, a collimating lens, one or more reflective mirrors, a slit, etc.

[0027] The spectroscopic optical system 4 is a part that decomposes the light L1 into wavelengths in a predetermined direction. The spectroscopic optical system 4 is configured to include a spectroscopic element that decomposes the light L1 into wavelengths in a predetermined direction. As the spectroscopic element, for example, a prism, a diffraction grating (grating), a concave diffraction grating, a crystal spectroscopic element, etc. can be used. The Raman scattered light Lr is spectroscopically separated by the spectroscopic optical system 4 and input to the spectroscopic device 5.

[0028] Figure 1In the embodiment, the spectroscopic optical system 4 and the spectroscopic device 5 are independently constituted, but the spectroscopic optical system 4 can also be incorporated as a component of the spectroscopic device 5. That is, the spectroscopic device 5 can also further include a spectroscopic optical system 4 including a spectroscopic element that spectroscopes the light L1 along the wavelength decomposition direction. In this case, the spectroscopic device 5 has a wavelength decomposition function of the light L1, thereby seeking to improve convenience. The spectroscopic device 5 is a part that receives the light L1 decomposed by the wavelength along a specified direction and outputs the spectroscopic spectrum data of the light L1. In the present embodiment, the spectroscopic device 5 receives the Raman scattered light Lr that is dispersed along the specified wavelength decomposition direction by the spectroscopic optical system 4, and outputs the spectroscopic spectrum data of the Raman scattered light Lr to the computer 6.

[0029] The computer 6 physically has storage devices such as RAM (Random Access Memory), ROM (Read Only Memory), processors (calculation circuits) such as CPU (Central Processing Uni), communication interfaces, etc. As the computer 6, for example, a personal computer, a cloud server, and an intelligent device (smartphone, tablet terminal, etc.) can be used. The computer 6 can be connected to the light source unit 2 and the spectrometer 5 of the Raman spectrometry device 1 for information communication with each other, and these components can be controlled comprehensively. The computer 6 also functions as an analysis unit 8 that analyzes the physical properties of the sample S based on the spectroscopic spectrum data received from the spectrometer 5 (generating unit 15). The computer 6 outputs information showing the analysis results of the analysis unit 8 to the display unit 7.

[0030] The spectroscopic device 5 is as follows Figure 1 As shown, the image sensor 10 includes a pixel unit 11, an accumulation unit 12, a readout unit 13, a conversion unit 14, and a generating unit 15. The pixel unit 11, the accumulation unit 12, and the readout unit 13 are composed of an image sensor 9. The conversion unit 14 is composed of a semiconductor element 10. The image sensor 9 is, for example, a solid-state image sensor composed of a charge coupled device of a CCD (Charge Coupled Device) type. The semiconductor element 10 has, for example, a CMOS (Complementary Metal Oxide Semiconductor) type semiconductor chip, and functions as the conversion unit 14 by a circuit embedded in the semiconductor chip.

[0031] In this embodiment, the spectroscopic device 5 is configured as a camera including an imaging element 9, a semiconductor element 10, and a generating unit 15. Here, the spectroscopic device 5 is independent of the computer 6, but the spectroscopic device 5 may be configured as a camera including an imaging element 9, a semiconductor element 10, and a generating unit 15, and a computer 6 (analyzer 8) electrically connected to the camera or connected to the camera so as to communicate information with each other through wireless communication. In this case, the computer 6 may also function as the generating unit 15 and the analyzing unit 8.

[0032] Figure 2 is a schematic diagram showing an example of a pixel unit. As shown in the figure, in the pixel unit 11, a plurality of pixels 21 are arranged in a row direction and a column direction perpendicular to the row direction. Here, the row direction is the wavelength decomposition direction of the light L1 or the Raman scattered light Lr along the spectroscopic optical system 4, and the column direction is the charge transfer direction along the pixel 21. Each pixel 21 receives the wavelength-decomposed light L1 or the Raman scattered light Lr, and generates and accumulates a charge corresponding to the intensity of the light.

[0033] exist Figure 2 In the example, the pixel unit 11 is formed into a horizontally long shape in which the number of pixels in the row direction is greater than the number of pixels in the column direction. For the pixel unit 11, five spectral images 31 (31A to 31E from the short wavelength side) after imaging wavelength decomposition are formed. The spectral images 31A to 31E all extend linearly in the column direction of the pixel 21, and are imaged on the pixel unit 11 in a state of being separated from each other in the row direction. In this case, in the spectroscopic device 5, for example Figure 3 As shown, spectral spectrum data 32 (32A to 32E) corresponding to the spectral spectrum images 31A to 31E are generated. The generated spectral spectrum data 32 (32A to 32E) are output from the spectroscopic device 5 (generating unit 15) to the computer 6.

[0034] As described above, the imaging element 9 includes the pixel unit 11, the storage unit 12, and the readout unit 13. The pixel unit 11 is a part for capturing the spectral spectrum image 31 of the light L1 or the Raman scattered light Lr formed by the spectral optical system 4. Figure 4 and Figure 5 As shown in FIG. 1 , the image sensor 9 includes a first pixel portion 11A and a second pixel portion 11B divided along the column direction. The first pixel portion 11A and the second pixel portion 11B are divided in the center along the column direction (see FIG. 1 ). Figure 2 ). That is, the pixel 21 on one side of the center in the column direction belongs to the first pixel portion 11A, and the pixel 21 on the other side of the center in the column direction belongs to the second pixel portion 11B.

[0035] The image sensor 9 includes a conversion substrate 40 for driving a pad for controlling the transfer of charges in the first pixel section 11A and the second pixel section 11B. The conversion substrate 40 is disposed, for example, on the side of the pixel section 11 along the column direction. A voltage signal (driving voltage) for controlling the transfer of charges of the pixels 21 is supplied to the conversion substrate 40. The charges of the pixels 21 in each column of the first pixel section 11A are transferred to the pixels 21 along the column direction based on the voltage signal supplied to the conversion substrate 40. Figure 4 The charges of the pixels 21 in each column of the second pixel unit 11B are transferred in the direction of the arrow A1 in the column direction based on the voltage signal supplied to the conversion substrate 40. Figure 5 Transmitted in the direction of arrow A2 (the opposite direction of arrow A1).

[0036] The storage unit 12 is a part for storing the charges generated in each column of pixels 21. The storage unit 12 is arranged at the end of the pixel unit 11 in the column direction. In this embodiment, the image sensor 9 has a first storage unit 12A corresponding to the first pixel unit 11A (see Figure 4 ), and the second storage unit 12B corresponding to the second pixel unit 11B (reference Figure 5 ). The first storage unit 12A is arranged at the end of the first pixel unit 11A in the column direction by column to store the charges generated in the pixels 21 in each column belonging to the first pixel unit 11A. The second storage unit 12B is arranged at the end of the second pixel unit 11B in the column direction by column to store the charges generated in the pixels 21 in each column belonging to the second pixel unit 11B. The first storage unit 12A is arranged at the first end of the pixel unit 11 in the column direction (the end on the first pixel unit 11A side), and the second storage unit 12B is arranged at the second end of the pixel unit 11 in the column direction (the end on the second pixel unit 11B side) (refer to Figure 2 ).

[0037] The storage unit 12 is as follows Figure 6 As shown, there is a floating gate electrode 41. The charge of the potential well 42 of each column of pixels 21 is transferred to the final potential well 42F of each column through the control gate electrode 43. In the final potential well 42F, for example, the charge of the number of pixels set by column is accumulated. After the charge of the set pixel amount is accumulated in the final potential well 42F, the voltage in the sense node 44 is output to the readout unit 13 via the floating gate electrode 41. After the output, a reset voltage is applied to the reset transistor 45, and the charge accumulated in the final potential well 42F is removed via the reset transistor 45.

[0038] The readout section 13 is a portion that outputs an electrical signal of each column corresponding to the magnitude of the charge accumulated in the storage section 12. In the present embodiment, the imaging element 9 includes a plurality of first readout sections 13A corresponding to each of the first storage sections 12A, and a plurality of second readout sections 13B corresponding to each of the second storage sections 12B. The first readout section 13A is disposed at the rear section of the first storage section 12A at the first end section in the column direction of the pixel section 11 (the end section on the first pixel section 11A side), and the second readout section 13B is disposed at the rear section of the second storage section 12B at the second end section in the column direction of the pixel section 11 (the end section on the second pixel section 11B side) (refer to Figure 2 ). The first readout section 13A outputs a first electrical signal of each column corresponding to the magnitude of the charge accumulated in the first accumulation section 12A. The second readout section 13B outputs a second electrical signal of each column corresponding to the magnitude of the charge accumulated in the second accumulation section 12B.

[0039] The first reading unit 13A is as follows Figure 4 As shown, a transistor 51A and a bonding pad 52A for signal output are provided. The control terminal (gate) of the transistor 51A is electrically connected to the first storage unit 12A. A current terminal (drain) of one of the transistors 51A is electrically connected to a bonding pad 54A via a wiring 53A provided in common across each column of the first pixel unit 11A. A voltage of a predetermined magnitude is always applied to the bonding pad 54A.

[0040] The other current terminal (source) of the transistor 51A is electrically connected to the signal output bonding pad 52A. A voltage corresponding to the first electrical signal output from the first storage unit 12A is applied to the control terminal of the transistor 51A. A current corresponding to the applied voltage is output from the other current terminal of the transistor 51A and is taken out through the signal output bonding pad 52A. The first electrical signal output from the signal output bonding pad 52A is passed through the amplifier 55 (reference Figure 6 ) is amplified and output to the conversion unit 14.

[0041] The second reading unit 13B is as follows Figure 5 As shown, a transistor 51B and a bonding pad 52B for signal output are provided. The control terminal (gate) of the transistor 51B is electrically connected to the second storage unit 12B. A current terminal (drain) of one of the transistors 51B is electrically connected to a bonding pad 54B via a wiring 53B provided in common across each column of the second pixel unit 11B. A voltage of a predetermined magnitude is always applied to the bonding pad 54B.

[0042] The other current terminal (source) of the transistor 51B is electrically connected to the signal output bonding pad 52B. A voltage corresponding to the second electrical signal output from the second storage unit 12B is applied to the control terminal of the transistor 51B. A current corresponding to the applied voltage is output from the other current terminal of the transistor 51B and is taken out through the signal output bonding pad 52B. The second electrical signal output from the signal output bonding pad 52B is passed through the amplifier 55 (reference Figure 6 ) is amplified and output to the conversion unit 14.

[0043] The conversion unit 14 is a part that converts the electrical signal of each column output from the readout unit 13 into a digital signal and outputs the digital signal. Figure 7 and Figure 8 As shown, the semiconductor element 10 includes a plurality of first conversion sections 14A corresponding to each of the first readout sections 13A, and a plurality of second conversion sections 14B corresponding to each of the second readout sections 13B. The first conversion section 14A converts the first electrical signal of each column output from the first readout section 13A into a digital signal and outputs it. The second conversion section 14B converts the second electrical signal of each column output from the second readout section 13B into a digital signal and outputs it. The semiconductor element 10 may also independently include a first semiconductor element constituting the first conversion section 14A, and a second semiconductor element constituting the second conversion section 14B.

[0044] The first conversion unit 14A is as follows Figure 7 As shown, there are bonding pads 61A, CDS (Correlated Double Sampling) circuits 62A, buffers 63A, A / D (Analog / Digital) conversion circuits 64A, and multiplexers 65A. The bonding pads 61A are electrically connected to the bonding pads 52A for signal output of the first readout unit 13A. The CDS circuit 62A reduces the noise of the first electrical signal input from the bonding pad 61A. The buffer 63A amplifies the first electrical signal input from the CDS circuit 62A. The A / D conversion circuit 64A converts the first electrical signal input from the buffer 63A into a first digital signal. The multiplexer 65A outputs the first digital signals of each column input from each of the A / D conversion circuits 64A to the generating unit 15.

[0045] The second conversion unit 14B is as follows Figure 8As shown, there are bonding pads 61B, CDS circuits 62B, buffers 63B, A / D conversion circuits 64B, and multiplexers 65B. The bonding pads 61B are electrically connected to the bonding pads 52B for signal output of the second readout unit 13B. The CDS circuit 62B reduces the noise of the second electrical signal input from the bonding pads 61B. The buffer 63B amplifies the second electrical signal input from the CDS circuit 62B. The A / D conversion circuit 64B converts the second electrical signal input from the buffer 63B into a second digital signal. The multiplexer 65B outputs the second digital signals of each column input from each of the A / D conversion circuits 64B to the generating unit 15.

[0046] In this embodiment, in the imaging element 9, the first exposure time T1 of each pixel 21 belonging to the first pixel unit 11A and the second exposure time T2 of each pixel 21 belonging to the second pixel unit 11B are different from each other. More specifically, Fig. 9 As shown, the first exposure time T1 of each pixel 21 belonging to the first pixel section 11A is shorter than the second exposure time T2 of each pixel 21 belonging to the second pixel section 11B. Therefore, during the period in which one frame of image data is obtained in the second pixel region 21B, multiple frames of image data are obtained in the first pixel region 21A. Fig. 9 In the example, the second exposure time T2 is an integral multiple of the first exposure time T1. In this example, while the second pixel unit 11B acquires image data of one frame, the first pixel unit 11A acquires image data of an integral multiple of the second pixel unit 11B.

[0047] The generating unit 15 is constituted by a computer system that physically has a storage device such as RAM, ROM, a processor (calculation circuit) such as CPU, a communication interface, etc. The generating unit 15 can be constituted by a PLC (programmable logic controller) or an FPGA (field-programmable gate array).

[0048] The generating unit 15 generates the first spectral spectrum data based on the first digital signal input from the first conversion unit 14A. In addition, the generating unit 15 generates the second spectral spectrum data based on the second digital signal input from the second conversion unit 14B. The first spectral spectrum data is obtained in the first pixel unit 11A at a relatively short first exposure time T1, for example, below the saturation level in all wavelength bands. The second spectral spectrum data is obtained in the second pixel unit 11B at a relatively long second exposure time T2, for example, above the saturation level in a certain wavelength band.

[0049] The generating unit 15 divides the entire spectrum into a saturated band and an unsaturated band of the second spectral spectrum data. In the saturated band, the second spectral spectrum data is above the saturation level, and the first spectral spectrum data does not reach the saturation level. In the unsaturated band, the second spectral spectrum data does not reach the saturation level and has a better S / N ratio than the first spectral spectrum data. The generating unit 15 combines the first spectral spectrum data of the saturated band with the second spectral spectrum data of the unsaturated band to generate spectral spectrum data output to the computer 6.

[0050] Fig.10 1 is a flow chart showing a spectroscopic method according to an embodiment of the present disclosure. The spectroscopic method is a method of receiving light decomposed by wavelength along a predetermined direction and obtaining spectroscopic spectrum data of the light. The spectroscopic method of this embodiment is implemented using the spectroscopic device 5 described above. Fig.10 As shown, the spectroscopic method includes a light receiving step (step S01), an accumulation step (step S02), a reading step (step S03), a conversion step (step S04), a generation step (step S05), and an analysis step (step S06).

[0051] In the light receiving step S01, the wavelength-decomposed light L1 or the Raman scattered light Lr is received by a plurality of pixels 21 arranged in a row direction along the wavelength decomposition direction and in a column direction perpendicular to the row direction. In the present embodiment, the light L1 or the Raman scattered light Lr is received in different exposure periods in the first pixel unit 11A and the second pixel unit 11B.

[0052] In the accumulation step S02, the charges generated in each column of pixels 21 are accumulated. In the present embodiment, the first accumulation section 12A accumulates the charges generated in each column of pixels 21 belonging to the first pixel section 11A, and the second accumulation section 12B accumulates the charges generated in each column of pixels 21 belonging to the second pixel section 11B. When the first accumulation section 12A and the second accumulation section 12B accumulate the charges corresponding to the number of pixels set for each column in the final potential well 42F, the voltage at the sense node 44 is output to the readout section 13 via the floating gate electrode 41. Thereafter, a reset voltage is applied to the reset transistor 45, and the charges accumulated in the final potential well 42F are discharged via the reset transistor 45.

[0053] In the readout step S03, the electrical signal of each column corresponding to the magnitude of the accumulated charge is output. In this embodiment, the first readout section 13A outputs the first electrical signal of each column corresponding to the magnitude of the charge accumulated in the first accumulation section 12A, and the second readout section 13B outputs the second electrical signal of each column corresponding to the magnitude of the charge accumulated in the second accumulation section 12B. The first electrical signal of each column and the second electrical signal of each column are respectively amplified by the amplifier 55 and then output to the conversion section 14.

[0054] In the conversion step S04, the electrical signal of each column is converted into a digital signal and output. In the present embodiment, the first conversion unit 14A converts the first electrical signal of each column output from the first readout unit 13A into the first digital signal of each column and outputs it, and the second conversion unit 14B converts the second electrical signal of each column output from the second readout unit 13B into the second digital signal of each column and outputs it. The first digital signal of each column converted from the first electrical signal of each column by the A / D conversion circuit 64A and the second digital signal of each column converted from the second electrical signal of each column by the A / D conversion circuit 64B are output to the generating unit 15.

[0055] In the generation step S05, the spectral spectrum data 32 is generated based on the digital signal. In the present embodiment, the first spectral spectrum data based on the first digital signal and the second spectral spectrum data based on the second digital signal are generated in the generation unit 15. The generation unit 15 combines the first spectral data of the saturation band and the second spectral data of the non-saturation band to generate the spectral spectrum data 32 output to the computer 6. The generated spectral spectrum data 32 is output to the analysis unit 8.

[0056] In the analysis step S06, the sample S is analyzed based on the spectral spectrum data 32 generated in the generation step S05. For example, the waveform, peak position, half-value width, etc. of the spectral spectrum are analyzed to evaluate various physical properties of the sample S, such as molecular structure, crystallinity, orientation, and distortion amount.

[0057] As described above, in the spectroscopic device 5, after receiving the light L1 decomposed by wavelength through the plurality of pixels 21 arranged in the row direction and the column direction and accumulating the charges generated in the pixels 21 of each column, the electrical signals of each column corresponding to the magnitude of the charges are output. Since these processes are performed by the CCD type imaging element 9, the increase of the readout noise when reading out the charges generated in the pixels 21 of each column can be avoided. In addition, when outputting the digital signal based on the electrical signal of each column, the readout becomes faster than the case where the horizontal transfer circuit is provided, and the noise caused by heat is also suppressed. Therefore, in the spectroscopic device 5, the spectroscopic spectrum data 32 can be obtained with an excellent SN ratio.

[0058] In the spectroscopic device 5, the imaging element 9 includes: a first pixel section 11A and a second pixel section 11B, which are divided along a column direction; a first storage section 12A and a second storage section 12B, wherein the first storage section 12A is arranged at the end of the column direction of the first pixel section 11A by column to store the charges generated in each column of pixels 21, and the second storage section 12B is arranged at the end of the column direction of the second pixel section 11B by column to store the charges generated in each column of pixels 21; and a first readout section 13A and a second readout section 13B, wherein the first readout section 13A outputs a first electrical signal corresponding to the size of the charges accumulated in the first storage section 12A, and the second readout section 13B outputs a second electrical signal corresponding to the size of the charges accumulated in the second storage section 12B.

[0059] In addition, the semiconductor element 10 includes a first conversion unit 14A that converts the first electrical signal of each column output from the first readout unit 13A into a digital signal and outputs it, and a second conversion unit 14B that converts the second electrical signal of each column output from the second readout unit 13B into a digital signal and outputs it. Thus, the first pixel unit 11A and the second pixel unit 11B can be used separately according to the form of the spectral spectrum image 31. Therefore, the spectral spectrum data 32 of various lights can be obtained with a good SN ratio.

[0060] In the spectroscopic device 5, the first exposure time T1 of each pixel 21 belonging to the first pixel unit 11A is shorter than the second exposure time T2 of each pixel 21 belonging to the second pixel unit 11B. According to this structure, for example, the spectral spectrum image 31 of the light L1 whose intensity varies depending on the wavelength can be obtained at different exposure times in the first pixel unit 11A and the second pixel unit 11B. In the present embodiment, by combining the saturated band of the first spectral spectrum data obtained at the relatively short exposure time T1 in the first pixel unit 11A and the non-saturated band of the second spectral spectrum data obtained at the relatively long exposure time T2 in the second pixel unit 11B, the spectral spectrum data 32 with a good SN ratio can be obtained in a high dynamic range.

[0061] In the Raman spectrometry device 1 configured by incorporating the above-mentioned packaging device 5, after receiving the wavelength-decomposed Raman scattered light Lr by a plurality of pixels 21 arranged in the row direction and the column direction, and accumulating the charge generated in each column of pixels 21, an electrical signal of each column corresponding to the size of the charge is output. Since these processes are performed by the CCD type imaging element 9, it is possible to avoid an increase in readout noise when reading out the charge generated in each column of pixels 21. In addition, when outputting a digital signal based on the electrical signal of each column, the readout becomes faster than in the case of providing a horizontal transfer circuit, and noise caused by heat is also suppressed. Therefore, in the Raman spectrometry device 1, the spectroscopic spectrum data 32 can be obtained with an excellent SN ratio.

[0062] The present disclosure is not limited to the above-mentioned embodiment, and various changes can be applied. For example, in the above-mentioned embodiment, the imaging element 9 has the first pixel section 11A and the second pixel section 11B divided along the column direction, but the first pixel section 11A and the second pixel section 11B can also be divided into the first pixel section 11A and the second pixel section 11B. Fig.11 As shown, it is divided along the row direction. Fig.11 In, with Figure 2 Similarly to the case of the first pixel section 11A, the image sensor 9 includes: a first storage section 12A which is arranged in columns at the ends of the first pixel section 11A in the column direction and stores the charges generated in each column of the pixels 21; and a second storage section 12B which is arranged in columns at the ends of the second pixel section 11B in the column direction and stores the charges generated in each column of the pixels 21. In addition, the image sensor 9 includes: a first readout section 13A which outputs a first electrical signal of each column corresponding to the magnitude of the charges accumulated in the first storage section 12A; and a second readout section 13B which outputs a second electrical signal of each column corresponding to the magnitude of the charges accumulated in the second storage section 12B.

[0063] exist Fig.11 In the example, the first storage unit 12A and the second storage unit 12B are both arranged along the end of one side of the column direction of the pixel unit 11. The first readout unit 13A and the second readout unit 13B are both arranged at the same end after the first storage unit 12A and the second storage unit 12B. Fig.11 In the example, the charge transfer direction of the pixel 21 belonging to the first pixel portion 11A and the charge transfer direction of the pixel 21 belonging to the second pixel portion 11B are in the same direction (both are the direction of arrow A3).

[0064] In the present embodiment, the first readout section 13A and the second readout section 13B are arranged in columns at the ends of the column direction of each pixel 21 in the pixel section 11. Therefore, the timing of removing the charge and applying the reset voltage can also be changed in columns. Here, the first exposure time T1 of each pixel 21 belonging to the first pixel section 11A and the second exposure time T2 of each pixel 21 belonging to the second pixel section 11B are equal to each other. On the other hand, when reading out the charge, the first readout section 13A outputs the first electrical signal of each column at the stage of accumulating the charge generated in the pixels 21 of the first number of rows in the first accumulation section 12A, and the second readout section 13B outputs the second electrical signal of each column at the stage of accumulating the charge generated in the pixels 21 of the second number of rows less than the first number of rows in the second accumulation section 12B.

[0065] That is, for each column of pixels 21 belonging to the first pixel unit 11A, a relatively large amount of charge is accumulated in the final potential well 42F before the first electrical signal is output, and the number of times the charge is reset is relatively reduced. In addition, for each column of pixels 21 belonging to the second pixel unit 11B, a relatively small amount of charge is accumulated in the final potential well 42F before the second electrical signal is output, and the number of times the charge is reset is relatively increased. In such a structure, the first pixel unit 11A and the second pixel unit 11B can also be used in a divided manner according to the spectral spectrum 31. Therefore, the spectral spectrum data 32 of various light L1 can be obtained with a good SN ratio.

[0066] For example, Fig.12 As shown in FIG. 1 , consider a case where light having a spectrum with a relatively weak signal intensity on the short wavelength side and a relatively strong signal intensity on the long wavelength side is input to the spectroscopic device 5 in a state of being decomposed by wavelength. In this case, it is considered that if a spectral spectrum image of the light decomposed by wavelength is captured at a fixed exposure time in a single pixel unit, the spectrum data on the short wavelength side becomes non-saturated as a whole but the S / N ratio cannot be sufficiently obtained, while the spectrum data on the long wavelength side becomes a good S / N ratio as a whole but becomes saturated at a wavelength with an intensity above a predetermined value.

[0067] In this regard, Fig.11 In the example, for example, the first pixel unit 11A captures the spectral images 31A to 31C on the short wavelength side, and the second pixel unit 11B captures the spectral images 31D and 31E on the long wavelength side. Furthermore, each column of pixels 21 belonging to the first pixel unit 11A accumulates relatively more charges in the final potential well 42F and then outputs the first electrical signal, while each column of pixels 21 belonging to the second pixel unit 11B accumulates relatively less charges in the final potential well 42F and then outputs the second electrical signal.

[0068] In this case, in the generating unit 15, as shown in FIG. Fig.13 As shown, the first spectrum data on the short wavelength side and the second spectrum data on the long wavelength side are generated. In the first spectrum data, by outputting the first electrical signal after accumulating relatively more charges, the sensitivity to the spectral images 31A to 31C becomes better, and the SN ratio is improved. In the second spectrum data, by outputting the second electrical signal after accumulating relatively less charges, saturation can be suppressed. Therefore, as Fig.14 As shown, by combining the first spectrum data and the second spectrum data to generate final spectral spectrum data, spectral spectrum data with a good SN ratio can be obtained in a high dynamic range.

[0069] Generally speaking, if Figure 2 As shown in FIG. 1 , the spectral images 31 (31A to 31E) are formed symmetrically with respect to the center of the column direction of the pixel unit 11. Fig.15As shown, the spectral image 31 (31A to 31E) may be formed at a position shifted in the column direction from the center of the column direction of the pixel portion 11. In fact, the spectral image 31 formed on the pixel portion 11 via the spectral optical system 4 is not linear due to the influence of the aberration of the optical system, such as represented by Czerny-Turner spectroscopy.

[0070] For example, in Fig.15 In the example of FIG. 1 , the spectral image 31C located at the center of the pixel unit 11 is formed in a straight line along the column direction, but the spectral images 31A, 31B and the spectral images 31D and 31E all have a so-called pincushion-shaped distortion in which the image is bent toward the center of the pixel unit 11. The distortion amount of the spectral image 31A increases as the spectral image moves away from the center of the pixel unit 11. The distortion amounts of the spectral images 31A and 31E are greater than the distortion amounts of the spectral images 31B and 31D.

[0071] In such a case, Fig.15 As shown in FIG. 1 , by shifting the spectral images 31A to 31E from the center of the column direction of the pixel unit 11 toward the column direction, it is possible to exclude the portions of the spectral images 31A to 31E that are greatly distorted from the photographing. Thus, even if distortion occurs in the spectral images 31A to 31E, it is possible to suppress the reduction in the wavelength resolution in the row direction in each of the spectral spectrum data 32A to 32E generated based on the distortion. In addition, it is possible to suppress the reduction in the wave height value and to seek an improvement in the SN ratio.

[0072] As another variation, the pixel portion 11 is not necessarily divided into the first pixel region 21A and the second pixel region 21B, and may also be composed of one pixel region. The spectrometer 5 is not limited to the application to the Raman spectrometer 1, and may also be applied to other spectrometers such as fluorescence spectrometers, plasma spectrometers, and luminescence spectrometers. In addition, the spectrometer 5 may also be applied to other spectrometers such as film thickness measurement devices, optical density (Optical Density) measurement, LIBS (Laser-Induced Breakdown Spectroscopy) measurement, and DOAS (Differential Optical Absorption Spectroscopy) measurement. Explanation of symbols

[0073] 1…Raman spectrometer; 2…light source; 3…light guiding optical system; 4…spectrometric optical system; 5…spectrometric device; 8…analyzer; 9…imaging element; 10…semiconductor element; 11…pixel; 11A…first pixel; 11B…second pixel; 12…accumulator; 12A…first reservoir; 12B…second reservoir; 13…readout; 13A…first readout; 13B…second readout; 14…converter; 14A…first converter; 14B…second converter; 15…generator; 31 (31A to 31E)…spectrometric spectrum image; 32 (32A to 32E)…spectrometric spectrum data; L1…light; Lr…Raman scattered light; T1…first exposure time; T2…second exposure time.

Claims

1. A spectroscopic device, wherein: A spectroscopic device receives light decomposed by wavelength in a predetermined direction by a spectroscopic optical system including a spectroscopic element and obtains spectroscopic spectrum data of the light. have: CCD type imaging element, semiconductor element and generating unit, The CCD type imaging element has: A pixel portion, wherein a plurality of pixels are arranged in a row direction along a wavelength separation direction of the light and in a column direction perpendicular to the row direction; an accumulation section arranged in columns at ends of the pixel section in the column direction and accumulating charges generated in the pixels of each column; and a readout section that outputs an electrical signal of each column corresponding to the magnitude of the charge accumulated in the accumulation section, The semiconductor element converts the electrical signal of each column output from the readout unit into a digital signal and outputs the digital signal. The generating unit generates spectroscopic spectrum data based on the digital signal output from the semiconductor element.

2. The spectroscopic device according to claim 1, wherein: The imaging element has: a first pixel portion and a second pixel portion, which are divided along the column direction; a first storage unit and a second storage unit, wherein the first storage unit is arranged at an end of the first pixel unit in the column direction by column to store charges generated in each column of pixels, and the second storage unit is arranged at an end of the second pixel unit in the column direction by column to store charges generated in each column of pixels; and a first readout section and a second readout section, wherein the first readout section outputs a first electrical signal of each column corresponding to the size of the charge accumulated in the first accumulation section, and the second readout section outputs a second electrical signal of each column corresponding to the size of the charge accumulated in the second accumulation section, The semiconductor element has: a first conversion section that converts the first electrical signal of each column output from the first readout section into a digital signal and outputs the digital signal; and The second converter converts the second electrical signal of each column output from the second readout section into a digital signal and outputs the digital signal.

3. The spectroscopic device according to claim 2, wherein: A first exposure time of each pixel belonging to the first pixel portion is shorter than a second exposure time of each pixel belonging to the second pixel portion.

4. The spectroscopic device according to claim 3, wherein: While the second pixel unit is acquiring image data of one frame, the first pixel unit is acquiring image data of a plurality of frames.

5. The spectroscopic device according to claim 1, wherein: The imaging element has: a first pixel portion and a second pixel portion, which are divided along the row direction; a first storage unit and a second storage unit, wherein the first storage unit is arranged at an end of the first pixel unit in the column direction by column to store charges generated in each column of pixels, and the second storage unit is arranged at an end of the second pixel unit in the column direction by column to store charges generated in each column of pixels; and A first readout unit and a second readout unit, wherein the first readout unit outputs a first electrical signal of each column corresponding to the size of the charge accumulated in the first accumulation unit, and the second readout unit outputs a second electrical signal of each column corresponding to the size of the charge accumulated in the second accumulation unit.

6. The spectroscopic device according to claim 5, wherein: The first readout section outputs the first electrical signal of each column at a stage where the charges generated in the pixels corresponding to the first number of rows are accumulated in the first accumulation section. The second readout section outputs the second electrical signal of each column at the stage of accumulating charges generated in pixels corresponding to a second number of rows smaller than the first number of rows in the second accumulation section.

7. The spectroscopic device according to any one of claims 1, 2 and 5, wherein: The device further comprises: an analyzing unit configured to analyze the spectroscopic spectrum data.

8. The spectroscopic device according to any one of claims 1, 2 and 5, wherein: The present invention further comprises: the spectroscopic optical system including the spectroscopic element.

9. A Raman spectrometry device, wherein: have: The spectroscopic device according to any one of claims 1, 2 and 5; a light source unit that generates light to irradiate the sample; and The light guide optical system guides the Raman scattered light generated by irradiating the sample with the light to the spectroscopic device.

10. A spectroscopic method, wherein: This is a spectroscopic method that receives light decomposed by wavelength along a predetermined direction and obtains the spectroscopic spectrum data of the light. have: A light receiving step, receiving the wavelength-decomposed light with a plurality of pixels arranged in a row direction along the wavelength decomposition direction and in a column direction perpendicular to the row direction; an accumulation step of accumulating charges generated in each column of pixels; a readout step of outputting an electrical signal of each column corresponding to the magnitude of the accumulated charge; A conversion step, converting the electrical signal of each column into a digital signal and outputting it; and The step of generating is to generate spectroscopic spectrum data based on the digital signal.

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