Spectrometer

Abstract

To provide a spectrometer capable of improving impact resistance of a photodetector.SOLUTION: A spectrometer 1 includes a spectroscopic unit 10 that includes a multichannel photodetector 15 and splits and detects measuring light; a circuit board 20 for processing a detection signal of the measuring light from the multichannel photodetector 15 as an electric signal; a signal output unit 30 for outputting the electric signal from the circuit board 20; and a housing 60. The circuit board 20 is held at an end of the multichannel photodetector 15 so as not to come into contact with the housing 60. The signal output unit 30 is held by the housing 60. The circuit board 20 and the signal output unit 30 are electrically connected to each other by a flexible cable 40.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a spectroscopic device. [Background technology]

[0002] Patent Document 1 describes an optical measurement device. This optical measurement device is provided with a fluorescence detection unit that detects fluorescence emitted from a sample irradiated with laser light. The fluorescence detection unit is provided with a multi-channel PMT (Photo-Multiplier Tube), a transmission diffraction grating, and a telecentric focusing lens. The multi-channel PMT is a detector that detects fluorescence emitted from the sample and is provided with multiple detection channels. In the multi-channel PMT, photons incident from an entrance window of a detection channel are converted into photoelectrons on a photocathode, amplified, and then output as an electrical signal. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 4711009 Summary of the Invention [Problem to be solved by the invention]

[0004] In optical measurement devices such as those described in Patent Document 1, in order to output a detection signal from a photodetector such as a multi-channel PMT, a circuit board equipped with a control circuit including a signal processing unit that converts the detection signal into a desired output format may be installed downstream of the photodetector. In this case, it is effective to place the circuit board immediately adjacent to the photodetector to reduce electrical noise and shorten the transmission distance of the detection signal. Therefore, in this case, it is possible to directly attach a unit including the circuit board to the photodetector. However, this would require a heavy object to be supported by the photodetector, increasing the load on the photodetector. As a result, the impact resistance of the multi-channel photodetector in the optical measurement device may be reduced.

[0005] SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a spectroscopic device capable of improving the impact resistance of a photodetector. [Means for solving the problem]

[0006] The spectroscopic device of the present invention is [1] "a spectroscopic device comprising: a spectroscopic unit including a multichannel photodetector that spectroscopically separates measurement light and detects it using the multichannel photodetector; a circuit board that processes a detection signal of the measurement light from the multichannel photodetector as an electrical signal; a signal output unit that outputs the electrical signal from the circuit board; and a housing that accommodates the spectroscopic unit, the circuit board, and the signal output unit, wherein the circuit board is held at an end of the multichannel photodetector so as not to come into contact with the housing, the signal output unit is held in the housing, and the circuit board and the signal output unit are electrically connected by a flexible cable that inputs the electrical signal from the circuit board to the signal output unit."

[0007] In this spectroscopic device, a circuit board for processing detection signals of measurement light from the multichannel photodetector as electrical signals is held at an end of the multichannel photodetector, while a signal output unit for outputting the electrical signals from the circuit board to the outside is provided separately from the circuit board and connected by a flexible cable. The signal output unit is held in a housing. Therefore, compared to a case in which a structure including the circuit board and the signal output unit is held in the multichannel photodetector, the load on the multichannel photodetector is reduced. As a result, the impact resistance of the multichannel photodetector is improved. Furthermore, the circuit board held in the multichannel photodetector is prevented from contacting the housing. Therefore, impact from outside the housing is prevented from being transmitted to the multichannel photodetector via the circuit board, further improving the impact resistance. Note that, by connecting the circuit board held in the multichannel photodetector and the signal output unit held in the housing by a flexible cable, the degree of freedom in the installation position of the multichannel photodetector is ensured.

[0008] The spectroscopic device according to the present invention may be [2] "the spectroscopic device according to the above [1], wherein the detection signal is a current signal, the circuit board includes a current / voltage converter for converting the current signal into a voltage signal, and the signal output unit outputs the voltage signal from the circuit board." In this case, the detection signal, which is a current signal from the multichannel photodetector, is converted into a voltage signal in the current / voltage converter of the circuit board held by the multichannel photodetector, and is input to the signal output unit via a flexible cable. This shortens the transmission distance of the current signal, thereby suppressing electrical noise.

[0009] The spectroscopic device according to the present invention may be [3] "the spectroscopic device according to the above [2], wherein the circuit board includes a first board on which the current / voltage conversion unit is provided and a second board on which the flexible cable connection unit is provided." In this way, the circuit board held by the multichannel photodetector may be divided into a board on which the current / voltage conversion unit is provided and a board on which the flexible cable connection unit is provided. In this case, even if there is some stress from the flexible cable, the influence on the multichannel photodetector can be suppressed, and the impact resistance of the multichannel photodetector can be improved.

[0010] The spectroscopic device according to the present invention may be [4] "the spectroscopic device according to any one of the above [1] to [3], wherein the housing is made of a conductive material." In this case, the influence of external noise is reduced by the housing made of a conductive material.

[0011] The spectroscopic device according to the present invention may be [5] "the spectroscopic device according to any one of the above [1] to [4], including a power supply unit housed in the housing for supplying voltage to the multichannel photodetector, and a conductive shield surrounding the power supply unit within the housing." In this case, electrical noise generated in the power supply unit can be blocked by the conductive shield.

[0012] The spectroscopic device according to the present invention may be [6] "the spectroscopic device according to the above [5], further comprising a power supply cable connecting the multichannel photodetector and the power supply unit, the power supply cable being fixed to the spectroscopic unit." In this case, it is possible to suppress the generation of electrical noise caused by the oscillation of the power supply cable.

[0013] The spectroscopic device according to the present invention may be [7] "the spectroscopic device according to any one of [1] to [6] above, wherein the spectroscopic unit includes a spectroscopic element that disperses the measurement light into a plurality of light beams to be detected, a holding unit that holds the spectroscopic element, and an adjustment unit that fixes the multichannel photodetector to the holding unit while adjusting the position of the multichannel photodetector relative to the holding unit in a plane intersecting the optical axis of the light beams to be detected so that each of the light beams to be detected is incident on a corresponding channel of the multichannel photodetector, and the circuit board is held at an end of the multichannel photodetector opposite to the adjustment unit." In this case, the adjustment unit can adjust the position of the multichannel photodetector relative to the holding unit so that each of the light beams to be detected from the spectroscopic element is incident on a corresponding channel of the multichannel photodetector. Positional fluctuations of the multichannel photodetector at this time are absorbed by the flexibility of the flexible cable and do not affect the installation position of the signal output unit.

[0014] The spectroscopic device according to the present invention may be [8] "the spectroscopic device according to the above [7], wherein the spectroscopic unit further includes a lens barrel fixed to the holder so as to receive the measurement light and cause the measurement light to be incident on the spectroscopic element, the lens barrel and the holder being fixed while in contact with each other, and a first light-shielding member being provided on the contact surface between the lens barrel and the holder so as to surround the optical path of the measurement light." In this case, the light-shielding property between the lens barrel and the holder is improved, and the influence of ambient light is reduced.

[0015] The spectroscopic device according to the present invention may be [9] "the spectroscopic device according to the above [7] or [8], wherein the adjustment unit and the holding unit are fixed while being in contact with each other, and a second light-shielding member is provided on the contact surface between the adjustment unit and the holding unit so as to surround the optical paths of the plurality of light beams to be detected." In this case, the light-shielding property between the adjustment unit and the holding unit is improved, and the influence of ambient light is reduced.

[0016] The spectroscopic device according to the present invention may be

[10] "the spectroscopic device according to any one of [7] to [9] above, wherein the adjustment unit and the multichannel photodetector are fixed in contact with each other, and a third light-shielding member is provided at the contact surface between the adjustment unit and the multichannel photodetector so as to surround the optical paths of the plurality of light beams to be detected." In this case, the light-shielding property between the adjustment unit and the multichannel photodetector is improved, and the influence of ambient light is reduced.

[0017] The spectroscopic device according to the present invention may be

[11] "the spectroscopic device according to any one of [7] to

[10] above, wherein the spectroscopic unit further includes a lens barrel portion fixed to the holder portion so as to receive the measurement light and cause the measurement light to be incident on the spectroscopic element, and a fiber holding portion for holding an end of an optical fiber that guides the measurement light is fixed to the end of the lens barrel portion opposite the holder portion while being in contact with the lens barrel portion, and a fourth light-shielding member is provided at the contact surface between the fiber holding portion and the lens barrel portion so as to surround the optical path of the measurement light." In this case, the light-shielding property between the fiber holding portion and the lens barrel portion is improved, and the influence of ambient light is reduced.

[0018] The spectroscopic device according to the present invention may be

[12] "the spectroscopic device according to any one of [7] to

[11] above, wherein the multichannel photodetector includes a detector body for detecting the plurality of light beams to be detected and a case for accommodating the detector body, the case including a cylindrical portion fixed to the adjustment unit while being in contact with the adjustment unit, and a lid portion provided on the cylindrical portion so as to close the cylindrical portion on the side opposite the adjustment unit, the detector body being sandwiched between the cylindrical portion and the lid portion when accommodated in the cylindrical portion, and a fifth light-shielding member being provided on the contact surface between the lid portion and the detector body so as to surround the detector body." In this case, the light-shielding property between the detector body and the lid portion of the case for accommodating the detector body of the multichannel photodetector is improved, and the influence of ambient light is reduced.

[0019] The spectroscopic device according to the present invention may be

[13] "the spectroscopic device according to the above

[12] , wherein the lid is fixed in contact with the cylindrical portion, and a sheet-like sixth light-shielding member is provided on the contact surface between the lid and the cylindrical portion so as to surround the detector body." In this case, the light-shielding property between the cylindrical portion of the case and the lid is improved, and the influence of ambient light is reduced.

[0020] The spectroscopic device according to the present invention may be

[14] "the spectroscopic device according to any one of the above

[12] to

[14] , wherein a through hole for passing a cable electrically connected to the detector body is formed in the case, and a gap between the inner surface of the through hole and the cable is filled with a light-shielding resin." In this case, the light-shielding property of the through hole for passing the cable in the case is improved, and the influence of ambient light is reduced.

[0021] The spectroscopic device according to the present invention may be

[15] "the spectroscopic device according to any one of [7] to

[14] above, in which the adjustment unit has a portion that protrudes outward from the holding unit when viewed from the arrangement direction of the holding unit and the adjustment unit." In this way, by having the adjustment unit have a portion that protrudes outward from the holding unit when viewed from the arrangement direction of the holding unit and the adjustment unit, for example, by providing a flange on the holding unit that overlaps the protruding portion of the adjustment unit, it becomes possible to access the overlapping portion of the flange and the adjustment unit from the arrangement direction and perform screw fastening, thereby improving manufacturability. [Effects of the Invention]

[0022] According to the present invention, it is possible to provide a spectroscopic device capable of improving the impact resistance of a photodetector. [Brief explanation of the drawings]

[0023] [Figure 1] FIG. 1 is a perspective view of a spectroscopic device according to this embodiment. [Figure 2] FIG. 2 is a perspective view showing the internal structure of the spectroscopic device shown in FIG. [Figure 3] FIG. 3 is a schematic cross-sectional view of the spectroscopic device shown in FIGS. [Figure 4] FIG. 4 is a schematic cross-sectional view showing an example of the multi-channel photodetector shown in FIG. [Figure 5] FIG. 5 is an exploded side view of the internal structure of the spectroscopic unit shown in FIG. [Figure 6] FIG. 6 is a schematic cross-sectional view for explaining the light-shielding structure of the spectroscopic unit shown in FIG. [Figure 7] FIG. 7 is a schematic cross-sectional view for explaining the light-shielding structure of the spectroscopic unit shown in FIG. [Figure 8] FIG. 8 is a perspective view for explaining the light-shielding structure of the spectroscopic device shown in FIG. [Figure 9] FIG. 9 is a schematic cross-sectional view for explaining the light-shielding structure of the spectroscopic device shown in FIG. [Figure 10]FIG. 10 is a perspective view showing the internal structure of the spectroscopic device shown in FIG. [Figure 11] FIG. 11 is a perspective view showing a part of the internal structure of the spectroscopic device shown in FIG. DETAILED DESCRIPTION OF THE INVENTION

[0024] A spectroscopic device according to an embodiment will be described below with reference to the drawings. In the description of the drawings, the same or corresponding elements are denoted by the same reference numerals, and redundant description may be omitted.

[0025] FIG. 1 is a perspective view of a spectroscopic device according to this embodiment. FIG. 2 is a perspective view showing the internal structure of the spectroscopic device shown in FIG. 1. FIG. 3 is a schematic cross-sectional view of the spectroscopic device shown in FIGS. 1 and 2. As shown in FIGS. 1 to 3, the spectroscopic device 1 includes a spectroscopic section 10, a circuit board 20, a signal output section 30, a flexible cable 40, a high-voltage power supply section (power supply section) 50, and a housing 60. Most of the spectroscopic section 10, the circuit board 20, the signal output section 30, the flexible cable 40, and the high-voltage power supply section 50 are housed in the housing 60. The spectroscopic device 1 is used by being incorporated into, for example, a fluorescence measuring device.

[0026] The spectroscopic unit 10 includes a holder 11, a lens barrel 12, a fiber holder 13, an adjuster 14, and a multichannel photodetector 15. The spectroscopic unit 10 disperses measurement light (e.g., fluorescence emitted from a sample) and detects the light using the multichannel photodetector 15. The holder 11 holds, for example, a transmission diffraction grating 110 (dispersing element) and multiple lenses 111 (two in the illustrated example). The diffraction grating 110 disperses the measurement light into multiple light beams to be detected. The lenses 111 are arranged on the optical path of the light beam to be detected emitted from the diffraction grating 110 and focus the light beam to be detected toward the multichannel photodetector 15.

[0027] The holding unit 11 has an internal space S11 in which an optical path of the measurement light directed toward the diffraction grating 110 and an optical path of the detection target light directed from the diffraction grating 110 toward the multichannel photodetector 15 via the lens 111 are formed. The diffraction grating 110 and the lens 111 are disposed and held within the internal space S11.

[0028] The lens barrel 12 is fixed to the holder 11 so as to receive input measurement light and cause the measurement light to be incident on the diffraction grating 110. Here, the lens barrel 12 is fixed to the holder 11 while being in contact with the holder 11. The lens barrel 12 holds an optical filter 121, such as a fluorescence filter, that removes predetermined excitation light, and a lens 122. The lens barrel 12 has an internal space S12 that forms an optical path for the measurement light toward the diffraction grating 110 held in the holder 11 and communicates with the internal space S11 of the holder 11. The optical filter 121 and the lens 122 are arranged and held in the internal space S12.

[0029] The fiber holding part 13 is provided at the end of the barrel part 12 opposite to the holding part 11. The fiber holding part 13 is fixed to the barrel part 12 while contacting the barrel part 12 so as to close the internal space S12 of the barrel part 12. The fiber holding part 13 includes a lid part 131 provided so as to close the internal space S12 of the barrel part 12, and a connector holding part 132 protruding from the lid part 131. The connector holding part 132 holds the end of an optical fiber that guides the measurement light via a connector provided at the end.

[0030] The adjustment unit 14 is fixed to the holding unit 11 while in contact with the holding unit 11, and is also fixed to the multichannel photodetector 15 while in contact with the multichannel photodetector 15. More specifically, the adjustment unit 14 includes an end face 14s and an end face 14r opposite to the end face 14s (see FIG. 7). The end faces 14s and 14r are substantially parallel to each other. The adjustment unit 14 is fixed to the holding unit 11 while in contact with the holding unit 11 at the end face 14r, and is fixed to the multichannel photodetector 15 while in contact with the holding unit 11 at the end face 14s. In this way, the adjustment unit 14 fixes the multichannel photodetector 15 to the holding unit 11.

[0031] The adjustment unit 14 has an internal space S14 in which optical paths of the plurality of light beams to be detected from the diffraction grating 110 are formed and which communicates with the internal space S11 of the holding unit 11. With the multichannel photodetector 15 fixed to the adjustment unit 14, the adjustment unit 14 adjusts the position of the multichannel photodetector 15 relative to the holding unit 11 in a plane intersecting the optical axes of the light beams to be detected so that each of the plurality of light beams to be detected enters a corresponding channel of the multichannel photodetector 15, thereby fixing the multichannel photodetector 15 to the holding unit 11.

[0032] FIG. 4 is a schematic cross-sectional view showing an example of the multichannel photodetector shown in FIG. 3. The multichannel photodetector 15 shown in FIGS. 3 and 4 is, for example, a multichannel HPD (Hybrid Photo Detector). As will be described later in detail as a detector body 151, an HPD is an electron tube that houses a photoelectric conversion unit and an electron detection unit consisting of a semiconductor element in a vacuum housing. The HPD is a photodetector element that performs electron multiplication by accelerating photoelectrons emitted from a photocathode by an electric field formed in the vacuum housing and causing them to be incident on the semiconductor element. In the multichannel HPD of this embodiment, the electron detection unit of the semiconductor element is multi-channeled, and can output independent detection signals for each channel. This allows detection of multiple light beams incident on different regions of the photocathode. In other words, measurement light separated into multiple light beams by the diffraction grating 110 can be detected by a single photodetector element without using multiple photodetectors.

[0033] The multichannel photodetector 15 includes a detector body 151 for detecting multiple light beams to be detected and a case 152 for accommodating the detector body 151. The detector body 151 includes a light entrance window 161, a photoelectric conversion unit 162, a side tube 163, a stem 164, a base member 165, pins 166, and an electron detection unit 167. The light entrance window 161, the side tube 163, and the stem 164 form a housing (vacuum housing). The light entrance window 161 is made of a light-transmitting material such as glass. The photoelectric conversion unit 162 is provided on the surface of the light entrance window 161 facing the electron detection unit 167. The photoelectric conversion unit 162 includes a photoelectric conversion layer made of a thin film of a compound semiconductor such as GaAs, and emits photoelectrons in response to the light beam to be detected incident through the light entrance window 161.

[0034] The side tube 163 is formed of an insulating material such as ceramic in a tubular shape with both ends open. One end of the side tube 163 is sealed by a light entrance window 161. The stem 164 is formed of an insulating material such as ceramic in a plate shape (disk shape in this case) and seals the other end of the side tube 163. This allows a vacuum region to be formed inside the side tube 163. In this embodiment, a voltage can be applied to the photoelectric conversion unit 162, for example, so that the stem 104 side is at GND potential (so that the photoelectric conversion unit 162 is at a negative potential and the stem 164 side is at ground potential).

[0035] The base member 165 is provided on the stem 164 so as to be located inside the side tube 163. The base member 165 is formed in the shape of a rectangular parallelepiped block from an insulating material such as ceramic. A plurality of pins 166 penetrate the base member 165 and the stem 164 so as to output the electrical signal (detection signal) output from the electronic detection unit 167 to the outside.

[0036] The electron detection unit 167 multiplies and detects electrons emitted from the photoelectric conversion unit 162. The electron detection unit 167 is, for example, a semiconductor element. The electron detection unit 167 is disposed inside the housing. The electron detection unit 167 is disposed on the base member 165 so as to face the photoelectric conversion unit 162. The electron detection unit 167 is, for example, an avalanche diode (AD).

[0037] The electron detection unit 167 receives photoelectrons from the photoelectric conversion unit 162, and multiplies the electrons through electron bombardment and further multiplies the electrons through avalanche multiplication. The electron detection unit 167 includes a plurality of channels arranged at a distance from one another. In other words, the electron detection unit 167 includes a sensitive region made up of a plurality of channels and a dead region formed between each channel. The electron detection unit 167 multiplies and detects photoelectrons in each of the plurality of channels.

[0038] The case 152 houses the above-described detector main body 151. The case 152 is fixed to the adjustment unit 14 while making contact with the adjustment unit 14. More specifically, the case 152 includes a cylindrical portion 171 that is fixed to the adjustment unit 14 while making contact with it, and a lid portion 172 that is provided on the cylindrical portion 171 so as to close the cylindrical portion 171 on the side opposite the adjustment unit 14. The detector main body 151 is sandwiched between the cylindrical portion 171 and the lid portion 172 while housed in the cylindrical portion 171. The lid portion 172 is fixed to the cylindrical portion 171 while making contact with it.

[0039] An opening 171h that passes the light to be detected is formed at the end of the cylindrical portion 171 opposite the lid portion 172. An optical filter 173 is provided at this end of the cylindrical portion 171 so as to cover the opening 171h. The optical filter 173 is, for example, a fluorescence filter that removes predetermined excitation light or transmits only predetermined fluorescence, or a secondary light cut filter that removes second-order diffracted light from the light to be detected from the diffraction grating 110.

[0040] Continuing with reference to Figures 1 to 3, the circuit board 20 processes the detection signal of the measurement light from the multichannel photodetector 15 as an electrical signal. The circuit board 20 includes an IV amplifier (current / voltage converter) for converting the detection signal of the measurement light (i.e., the light to be detected) from the multichannel photodetector 15 into a voltage signal. More specifically, the circuit board 20 includes a first board 21 on which the IV amplifier is provided, and a second board 22 on which a connection portion of the flexible cable 40 is provided. The first board 21 and the second board 22 are fixed integrally to the multichannel photodetector 15 in a state in which they are parallel to each other. In this embodiment, the first board 21 is positioned closer to the multichannel photodetector 15 than the second board 22.

[0041] The circuit board 20 (i.e., the first board 21 and the second board 22) is held at an end of the multichannel photodetector 15 so as not to come into contact with the housing 60. The circuit board 20 is fixed and held at an end of the case 152 of the multichannel photodetector 15 on the lid section 172 side (i.e., the end opposite the adjustment section 14) by fixing members such as screws (not shown). Note that "the circuit board 20 does not come into contact with the housing 60" means that a gap is formed between the circuit board 20 and the inner surface of the housing 60 around the entire periphery. Furthermore, "the circuit board 20 does not come into contact with the housing 60" also includes a case where a member different from the circuit board 20 (for example, an elastic member having higher shock absorption capacity than the circuit board 20 and the housing 60) is interposed between the circuit board 20 and the housing 60.

[0042] The signal output unit 30 includes a plurality of (three in the illustrated example) signal processing boards 31 and a plurality of (the same number as the signal processing boards 31) output connectors 32. The signal processing boards 31 are stacked parallel to one another with spacers 33 interposed therebetween and fixed to the bottom plate 61 of the housing 60. Each of the signal processing boards 31 is provided with a connection portion 34 for a flexible cable 40. This allows the circuit board 20 and the signal output unit 30 to be connected by the flexible cable 40. Note that a portion of the signal output unit 30 may include a configuration other than signal processing, for example, a configuration for transmitting or generating power to drive the spectroscopic device 1. In this embodiment, the lowest board of the signal processing boards 31 may be a driving power board 31E, and the lowest connector of the output connector 32 may be a driving power introduction connector 32E.

[0043] The flexible cable 40 is a flat flexible cable in which an electric circuit such as wiring is formed on a thin film of resin, and inputs a voltage signal from the circuit board 20 to the signal output unit 30 (signal processing board 31). The signal processing boards 31 each include a signal processing circuit that converts the voltage signal input via the flexible cable 40 into a desired output format. The output connector 32 is held and exposed to the rear panel 62 of the housing 60. In this way, the signal output unit 30 as a whole is held in the housing 60.

[0044] The high-voltage power supply unit 50 is disposed below the holder 11. The high-voltage power supply unit 50 is housed in a box-shaped conductive shield, for example, a metal shield 55, and is thereby surrounded by the metal shield 55. The high-voltage power supply unit 50 includes a high-voltage generating circuit equipped with a boost circuit and is intended to supply voltage to the multichannel photodetector 15. For this purpose, power supply cables 51 and 52 extend from the high-voltage power supply unit 50 (i.e., the metal shield 55). The power supply cable 51 extends upward (toward the holder 11) from the high-voltage power supply unit 50, is routed along the outer surface 11a and the top surface 11b of the holder 11, and is connected to the circuit board 20 (see FIG. 10 ). As a result, a voltage for avalanche multiplication (for example, −several hundred V) is supplied to the multichannel photodetector 15 via the circuit board 20.

[0045] The power supply cable 52 extends rearward (toward the multichannel photodetector 15) from the high-voltage power supply unit 50, is introduced into the case 152 through a through hole 172h formed in the lid 172 of the case 152 of the multichannel photodetector 15, and is connected to the photoelectric conversion unit 162. This allows a voltage for electron multiplication (for example, several kV) to be supplied to the multichannel photodetector 15. The spectrometer 1 is also provided with a power supply cable 53. The power supply cable 53 extends forward from the drive power board 31E and is connected to the circuit board 20 (first board 21) (see FIG. 10). This allows a voltage for driving the IV amplifier to be supplied to the circuit board 20.

[0046] The housing 60 is made of a conductive material, for example, metal, and houses most of the spectroscopic unit 10, the circuit board 20, the signal output unit 30, the flexible cable 40, and the high-voltage power supply unit 50 (and the metal shield 55), as described above. The housing 60 is also electrically connected to the GND potential of the circuit board 20 and has the same potential as the GND potential of the circuit board 20. A part of the spectroscopic unit 10, i.e., the part of the lens barrel unit 12 on the fiber holding unit 13 side and the fiber holding unit 13, protrudes to the outside from the housing 60. In the spectroscopic device 1, for example, the adjustment unit 14 that precisely adjusts the position of the multichannel photodetector 15 with respect to the light to be detected and the like are housed within the housing 60, thereby preventing the user and the like from coming into contact with the adjustment unit 14 and the like.

[0047] Next, the light-shielding structure of each part of the spectroscopic device 1 will be described. Fig. 5 is an exploded side view of the internal structure of the spectroscopic device shown in Fig. 2. As shown in Fig. 5, the spectroscopic device 1 has a first light-shielding member 71 interposed between the lens barrel part 12 and the holder 11 of the spectroscopic device 10, a second light-shielding member 72 interposed between the holder 11 and the adjustment part 14, a third light-shielding member 73 interposed between the adjustment part 14 and the multichannel photodetector 15, and a fourth light-shielding member 74 interposed between the fiber holder 13 and the lens barrel part 12.

[0048] As shown in FIG. 6(a), the fourth light-shielding member 74 is disposed on the contact surface between the fiber holding unit 13 and the barrel unit 12. Here, the contact surface between the fiber holding unit 13 and the barrel unit 12 is the end face 12s of the barrel unit 12 on the fiber holding unit 13 side. The fourth light-shielding member 74 is disposed in a groove provided in the end face 12s, and is elastically deformed by being pressed between the fiber holding unit 13 and the barrel unit 12. The fourth light-shielding member 74 is formed in an annular (e.g., circular) shape from a light-shielding resin. The fourth light-shielding member 74 is, for example, an O-ring. The fourth light-shielding member 74 is disposed so as to surround the optical path of the measurement light.

[0049] As shown in FIG. 6(b), the first light-shielding member 71 is disposed on the contact surface between the lens barrel 12 and the holder 11. Here, the contact surface between the lens barrel 12 and the holder 11 is the end face 12r of the lens barrel 12 on the holder 11 side. The first light-shielding member 71 is disposed in a groove provided in the end face 12r, and is elastically deformed by being pressed between the lens barrel 12 and the holder 11. The first light-shielding member 71 is formed in an annular (e.g., circular) shape from a light-shielding resin. The first light-shielding member 71 is, for example, an O-ring. The first light-shielding member 71 is disposed so as to surround the optical path of the measurement light.

[0050] As shown in FIG. 7(a), the second light-shielding member 72 is disposed on the contact surface between the holder 11 and the adjustment unit 14. Here, the contact surface between the holder 11 and the adjustment unit 14 is the end face 11s of the holder 11 on the adjustment unit 14 side. The second light-shielding member 72 is disposed in a groove provided in the end face 11s, and is elastically deformed by being pressed between the holder 11 and the adjustment unit 14. The second light-shielding member 72 is formed in an annular (e.g., circular) shape from a light-shielding resin. The second light-shielding member 72 is, for example, an O-ring. The second light-shielding member 72 is disposed so as to surround the optical path of the light to be detected.

[0051] As shown in FIG. 7(b), the third light-shielding member 73 is disposed at the contact surface between the adjustment unit 14 and the multichannel photodetector 15 (the cylindrical portion 171 of the case 152). Here, the contact surface between the adjustment unit 14 and the multichannel photodetector 15 is the end surface 14s of the adjustment unit 14 on the multichannel photodetector 15 side. The third light-shielding member 73 is disposed in a groove provided in the end surface 14s, and is elastically deformed by being pressed between the adjustment unit 14 and the multichannel photodetector 15. The third light-shielding member 73 is formed in an annular (e.g., circular) shape from a light-shielding resin. The third light-shielding member 73 is, for example, an O-ring. The third light-shielding member 73 is disposed so as to surround the optical path of the light to be detected.

[0052] 8 and 9, the spectrometer 1 includes a fifth light-shielding member 75 and a sixth light-shielding member 76. In FIG. 8, the fifth light-shielding member 75 and the sixth light-shielding member 76 are hatched in the perspective view for ease of understanding. In FIG. 9, hatching of members other than the light-shielding members is omitted. The fifth light-shielding member 75 is interposed between the lid 172 of the case 152 of the multichannel photodetector 15 and the detector body 151.

[0053] More specifically, the fifth light-shielding member 75 is disposed on the contact surface between the lid portion 172 and the detector body 151 (here, the stem 164). Here, the contact surface between the lid portion 172 and the detector body 151 is the end surface 172s of the lid portion 172 on the detector body 151 side. The fifth light-shielding member 75 is disposed in a groove provided in the end surface 151s, and is pressed between the lid portion 172 and the multichannel photodetector 15, causing it to elastically deform. The fifth light-shielding member 75 is formed in an annular (e.g., circular) shape from a light-shielding resin. The fifth light-shielding member 75 is, for example, an O-ring. The fifth light-shielding member 75 is disposed so as to surround the detector body 151.

[0054] The sixth light-shielding member 76 is disposed on the contact surface between the lid portion 172 and the cylindrical portion 171 of the case 152 of the multichannel photodetector 15. Here, the contact surface between the lid portion 172 and the cylindrical portion 171 is the end surface 172s of the lid portion 172. The sixth light-shielding member 76 is disposed over the entire end surface 172s. The sixth light-shielding member 76 is formed from a light-shielding resin in a sheet shape (i.e., a ring-shaped sheet shape) having an opening. The sixth light-shielding member 76 is disposed so as to surround the detector main body 151.

[0055] Furthermore, in the spectroscopic device 1, as described above, a through hole 172h is formed in the lid portion 172 of the case 152 for passing the power supply cable 52 electrically connected to the detector body 151, and the gap between the inner surface of the through hole 172h and the power supply cable 52 is filled with a light-blocking resin.

[0056] Next, a structure for countering electrical noise in the spectroscopic device 1 will be described. Fig. 10 is a perspective view showing the internal structure of the spectroscopic device shown in Fig. 1. As shown in Figs. 2 and 10, in the spectroscopic device 1, a housing 60 that houses each part of the spectroscopic device 1 is made of a conductive material such as metal. Also, in the spectroscopic device 1, the high-voltage power supply unit 50 is surrounded by a metal shield 55. Furthermore, in the spectroscopic device 1, power supply cables 51 and 52 extending from the high-voltage power supply unit 50 (i.e., the metal shield 55) are fixed to the spectroscopic unit 10.

[0057] More specifically, the power feed cable 51 extending upward from the high-voltage power supply unit 50 is routed from the outer surface 11a to the upper surface 11b of the holder 11 of the spectroscopic unit 10, and is fixed to the outer surface 11a by a clamp member 11c provided on the outer surface 11a. Furthermore, the power feed cable 52 extending rearward from the high-voltage power supply unit 50 is fixed to a back surface 55s by a clamp member 55c provided on the back surface (the surface on the signal output unit 30 side) of the metal shield 55. This prevents the power feed cables 51 and 52 from swinging.

[0058] Fig. 11 is a perspective view showing a part of the internal structure of the spectroscopic device shown in Fig. 2. As shown in Fig. 11, in the spectroscopic device 1, the width W14 of the adjustment unit 14 is larger than the width W11 of the holding unit 11 in a direction intersecting the arrangement direction of the holding unit 11 and the adjustment unit 14 (the optical axis direction of the measurement light and the light to be detected). In other words, the adjustment unit 14 has a portion 14p that protrudes outward from the holding unit 11 when viewed from the arrangement direction of the holding unit 11 and the adjustment unit 14.

[0059] For this reason, for example, by providing a flange on the holding portion 11 that overlaps the protruding portion 14p of the adjustment portion 14, it becomes possible to access the overlapping portion between the flange and the portion 14p from the arrangement direction and screw them together, thereby improving manufacturability.

[0060] As described above, in the spectroscopic device 1 according to this embodiment, the circuit board 20 for processing the detection signal of the measurement light (light to be detected) from the multichannel photodetector 15 as an electrical signal is held at an end of the multichannel photodetector 15, while the signal output unit 30 for outputting the electrical signal from the circuit board 20 to the outside is provided separately from the circuit board 20 and connected by a flexible cable 40. The signal output unit 30 is held in the housing 60. Therefore, compared to when a unit including the circuit board and the signal output unit 30 is held in the multichannel photodetector 15, the load on the multichannel photodetector 15 is reduced. As a result, the impact resistance of the multichannel photodetector 15 is improved.

[0061] Furthermore, the circuit board 20 held in the multichannel photodetector 15 is designed not to come into contact with the housing 60. This prevents shocks from the outside of the housing 60 from being transmitted to the multichannel photodetector 15 via the circuit board 20, further improving shock resistance. Note that the circuit board 20 held in the multichannel photodetector 15 and the signal output unit 30 held in the housing 60 are connected by a flexible cable, ensuring a degree of freedom in the installation position of the multichannel photodetector 15.

[0062] Here, in the spectroscopic device 1, the number of output connectors 32 of the signal output unit 30 may be changed in response to a request. In this case, in the spectroscopic device 1, it is not necessary to change the entire configuration of the unit including the circuit board 20 and the signal output unit 30, and it is possible to accommodate this by changing only the signal output unit 30.

[0063] Furthermore, in the spectroscopic device 1 according to this embodiment, the detection signal from the multichannel photodetector 15 is a current signal, and the circuit board 20 includes an IV amplifier for converting the current signal into a voltage signal. The signal output unit 30 outputs the voltage signal from the circuit board 20. Therefore, the detection signal, which is a current signal from the multichannel photodetector 15, is converted into a voltage signal in the IV amplifier of the circuit board 20 held by the multichannel photodetector 15, and is input to the signal output unit 30 via the flexible cable 40. This shortens the transmission distance of the current signal, thereby suppressing electrical noise.

[0064] Furthermore, in the spectroscopic device 1 according to this embodiment, the circuit board 20 includes a first board 21 on which an IV amplifier is provided and a second board 22 on which a connection portion for the flexible cable 40 is provided. In this manner, the circuit board 20 held by the multichannel photodetector 15 may be divided into a board on which the IV amplifier is provided and a board on which a connection portion for the flexible cable 40 is provided. In this case, even if some stress is applied from the flexible cable 40, the influence on the multichannel photodetector 15 can be suppressed, and the impact resistance of the multichannel photodetector 15 is improved.

[0065] Furthermore, in the spectroscopic device 1 according to this embodiment, the housing 60 is made of a conductive material such as metal. Therefore, the housing 60 made of a conductive material reduces the influence of external noise. In addition, light blocking properties are also improved.

[0066] The spectroscopic device 1 according to this embodiment also includes a high-voltage power supply unit 50 housed in a housing 60 for supplying voltage to the multichannel photodetector 15, and a metal shield 55 surrounding the high-voltage power supply unit 50 within the housing 60. This makes it possible for the metal shield 55 to block electrical noise generated in the high-voltage power supply unit 50.

[0067] The spectroscopic device 1 according to this embodiment also includes power supply cables 51 and 52 that connect the multichannel photodetector 15 and the high-voltage power supply unit 50. The power supply cables 51 and 52 are fixed to the spectroscopic unit 10. This makes it possible to suppress the generation of noise caused by the vibration of the power supply cables 51 and 52.

[0068] Furthermore, in the spectroscopic device 1 according to this embodiment, the spectroscopic unit 10 includes a diffraction grating 110 that splits the measurement light into multiple light beams to be detected, a holder 11 that holds the diffraction grating 110, and an adjustment unit 14 that fixes the multichannel photodetector 15 to the holder 11 while adjusting the position of the multichannel photodetector 15 relative to the holder 11 in a plane intersecting the optical axis of the light beams to be detected so that each of the multiple light beams to be detected is incident on a corresponding channel of the multichannel photodetector 15. The circuit board 20 is held at an end of the multichannel photodetector 15 opposite the adjustment unit 14. Therefore, the adjustment unit 14 can adjust the position of the multichannel photodetector 15 relative to the holder 11 so that each of the light beams to be detected from the diffraction grating 110 is incident on a corresponding channel of the multichannel photodetector 15. Any positional fluctuation of the multichannel photodetector 15 at this time is absorbed by the flexibility of the flexible cable 40 and does not affect the installation position of the signal output unit 30.

[0069] Furthermore, in the spectroscopic device 1 according to this embodiment, the spectroscopic unit 10 has a lens barrel 12 fixed to the holder 11 so as to receive input of measurement light and cause the measurement light to be incident on the diffraction grating 110. The lens barrel 12 and the holder 11 are fixed while being in contact with each other, and an annular first light-shielding member 71 that surrounds the optical path of the measurement light is provided on the contact surface between the lens barrel 12 and the holder 11 (the end surface 12r of the lens barrel 12 on the holder 11 side). This improves the light-shielding performance between the lens barrel 12 and the holder 11, reducing the effects of ambient light.

[0070] Furthermore, in the spectroscopic device 1 according to this embodiment, the adjuster 14 and the holder 11 are fixed while being in contact with each other, and an annular second light-shielding member 72 that surrounds the optical paths of the plurality of light beams to be detected is provided on the contact surface between the adjuster 14 and the holder 11 (the end surface 11s of the holder 11 on the adjuster 14 side). This improves the light-shielding performance between the adjuster 14 and the holder 11, and reduces the influence of ambient light.

[0071] Furthermore, in the spectroscopic device 1 according to this embodiment, the adjustment unit 14 and the multichannel photodetector 15 are fixed while being in contact with each other, and an annular third light-shielding member 73 that surrounds the optical paths of the multiple light beams to be detected is provided on the contact surface between the adjustment unit 14 and the multichannel photodetector 15 (the end surface 14s of the adjustment unit 14 on the multichannel photodetector 15 side). This improves the light-shielding performance between the adjustment unit 14 and the multichannel photodetector 15, and reduces the influence of ambient light.

[0072] Furthermore, in the spectroscopic device 1 according to this embodiment, a fiber holding part 13 for holding an end of an optical fiber that guides the measurement light is fixed in contact with the barrel part 12 at the end of the barrel part 12 opposite to the holding part 11, and an annular fourth light-shielding member 74 that surrounds the optical path of the measurement light is provided at the contact surface between the fiber holding part 13 and the barrel part 12 (the end surface 12s of the barrel part 12 on the fiber holding part 13 side). This improves the light-shielding property between the fiber holding part 13 and the barrel part 12, and reduces the influence of ambient light.

[0073] Furthermore, in the spectroscopic device 1 according to this embodiment, the multichannel photodetector 15 includes a detector body 151 for detecting a plurality of light beams to be detected, and a case 152 for accommodating the detector body 151. The case 152 includes a cylindrical portion 171 that is fixed to the adjustment unit 14 while being in contact with the adjustment unit 14, and a lid portion 172 that is provided on the cylindrical portion 171 so as to close the cylindrical portion 171 on the side opposite the adjustment unit 14. When accommodated in the cylindrical portion 171, the detector body 151 is sandwiched between the cylindrical portion 171 and the lid portion 172. An annular fifth light-shielding member 75 that surrounds the detector body 151 is provided on the contact surface between the lid portion 172 and the detector body 151 (an end surface 172s of the lid portion 172 on the detector body 151 side). This improves the light-shielding performance between the lid portion 172 of the case 152 and the detector body 151, thereby reducing the influence of ambient light.

[0074] Furthermore, in the spectroscopic device 1 according to this embodiment, the lid portion 172 is fixed while being in contact with the cylindrical portion 171, and a sixth light-shielding member 76 in the form of an annular sheet is provided on the contact surface between the lid portion 172 and the cylindrical portion 171 (the end surface 172s of the lid portion 172 on the detector body 151 side) so as to surround the detector body 151. This improves the light-shielding property between the cylindrical portion 171 and the lid portion 172 of the case 152, and reduces the influence of ambient light.

[0075] Furthermore, in the spectroscopic device 1 according to this embodiment, a through hole 172h is formed in the case 152 (here, the lid 172) for passing the power supply cable 52 electrically connected to the detector body 151, and a light-blocking resin is filled in the gap between the inner surface of the through hole 172h and the power supply cable 52. This improves the light-blocking properties of the through hole 172h in the case 152 for passing the power supply cable 52, reducing the influence of ambient light.

[0076] Furthermore, in the spectroscopic device 1 according to this embodiment, when viewed from the arrangement direction of the holding unit 11 and the adjustment unit 14, the adjustment unit 14 has a portion 14p that protrudes outward from the holding unit 11. In this way, by having the adjustment unit 14 have a portion 14p that protrudes outward from the holding unit 11, for example, by providing a flange on the holding unit 11 that overlaps the protruding portion 14p of the adjustment unit 14, it becomes possible to access the overlapping portion between the flange and portion 14p from the arrangement direction and perform screw fastening, thereby improving manufacturability.

[0077] The above embodiment has described one aspect of the spectroscopic device according to the present invention. Therefore, the spectroscopic device according to the present invention is not limited to the spectroscopic device 1 according to the above embodiment, and can be modified as desired.

[0078] For example, in the above embodiment, the circuit board 20 includes the first board 21 on which the IV amplifier is provided and the second board 22 on which the connection portion of the flexible cable 40 is provided. However, the circuit board 20 may be configured as a single board on which both the IV amplifier and the connection portion of the flexible cable 40 are provided.

[0079] In addition, in the light-shielding structure of the spectroscopic device 1, at least one of the first light-shielding member 71, the second light-shielding member 72, the third light-shielding member 73, the fourth light-shielding member 74, the fifth light-shielding member 75, and the sixth light-shielding member 76 may be omitted, and the passage hole 172h may not be filled with light-shielding resin. Furthermore, in the countermeasure structure for electrical noise of the spectroscopic device 1, the metal shield 55 may be omitted.

[0080] Furthermore, the multichannel photodetector 15 may be a multichannel photomultiplier tube or a multichannel semiconductor photodetector element. Furthermore, the circuit board 20 may output a current signal from the multichannel photodetector 15 from the signal output unit 30 without including an IV amplifier. In this case, the circuit board 20 processes the electrical signal as a relay member for the current signal from the multichannel photodetector 15 to the flexible cable 40. Furthermore, the flexible cable 40 may be another type of flexible cable, such as a coaxial cable. Furthermore, each light-shielding member is not limited to being formed in a ring shape (for example, a circular ring) from a light-shielding resin, and may be made of other materials and have other shapes. [Explanation of symbols]

[0081] 1...spectroscopic device, 10...spectroscopic section, 11...holding section, 12...optical tube section, 13...fiber holding section, 14...adjustment section, 14p...section, 15...multichannel photodetector, 20...circuit board, 21...first board, 22...second board, 30...signal output section, 40...flexible cable (flexible cable), 50...high-voltage power supply section (power supply section), 51, 52, 53...power supply cable (cable), 55...metal shield (conductive shield), 60...casing, 71...first light-shielding member, 72...second light-shielding member, 73...third light-shielding member, 74...fourth light-shielding member, 75...fifth light-shielding member, 76...sixth light-shielding member, 110...diffraction grating (spectroscopic element), 151...detector body, 152...case, 171...cylindrical section, 172...lid section, 172h...passage hole.

Claims

1. a spectroscopic unit including a multi-channel photodetector, which splits the measurement light and detects it using the multi-channel photodetector; a circuit board for processing the detection signal of the measurement light from the multi-channel photodetector as an electrical signal; a signal output unit for outputting the electrical signal from the circuit board; a housing that houses the spectroscopic unit, the circuit board, and the signal output unit; Equipped with the circuit board is held at an end of the multi-channel photodetector so as not to contact the housing; the signal output unit is held by the housing, the circuit board and the signal output unit are electrically connected by a flexible cable for inputting the electrical signal from the circuit board to the signal output unit; Spectroscopic device.

2. the detection signal is a current signal, the circuit board includes a current / voltage converter for converting the current signal into a voltage signal; the signal output unit outputs the voltage signal from the circuit board. The spectroscopic device of claim 1 .

3. the circuit board includes a first board on which the current / voltage conversion unit is provided and a second board on which a connection portion of the flexible cable is provided; 3. The spectroscopic device of claim 2.

4. The housing is made of a conductive material. The spectroscopic device of claim 1 .

5. a power supply unit housed in the housing for supplying a voltage to the multi-channel photodetector; a conductive shield surrounding the power supply unit within the housing; Equipped with The spectroscopic device of claim 1 .

6. a power supply cable connecting the multi-channel photodetector and the power supply unit; the power supply cable is fixed to the spectroscopic unit; The spectroscopic device according to claim 5 .

7. The spectroscopic unit a spectroscopic element that separates the measurement light into a plurality of light beams to be detected; a holder for holding the spectroscopic element; an adjustment unit for fixing the multichannel photodetector to the holding unit while adjusting a position of the multichannel photodetector with respect to the holding unit in a plane intersecting an optical axis of the light to be detected so that each of the plurality of light to be detected is incident on a corresponding channel of the multichannel photodetector; and the circuit board is held at an end of the multi-channel photodetector opposite to the adjustment unit; The spectroscopic device of claim 1 .

8. the spectroscopic unit further includes a lens barrel unit fixed to the holding unit so as to receive the measurement light and cause the measurement light to be incident on the spectroscopic element; the lens barrel portion and the holder portion are fixed in contact with each other, a first light-shielding member is provided on a contact surface between the lens barrel portion and the holder portion so as to surround an optical path of the measurement light; 8. The spectroscopic device of claim 7.

9. the adjustment portion and the holding portion are fixed to each other while being in contact with each other, a second light-blocking member is provided on a contact surface between the adjustment unit and the holding unit so as to surround the optical paths of the plurality of light beams to be detected; 8. The spectroscopic device of claim 7.

10. the adjustment unit and the multi-channel photodetector are fixed in contact with each other, a third light-blocking member is provided on a contact surface between the adjustment unit and the multichannel photodetector so as to surround the optical paths of the plurality of light beams to be detected; 8. The spectroscopic device of claim 7.

11. the spectroscopic unit further includes a lens barrel unit fixed to the holding unit so as to receive the measurement light and cause the measurement light to be incident on the spectroscopic element; a fiber holding part for holding an end of an optical fiber that guides the measurement light is fixed to an end of the barrel part opposite to the holding part while being in contact with the barrel part; a fourth light-shielding member is provided on a contact surface between the fiber holding portion and the lens barrel portion so as to surround an optical path of the measurement light; 8. The spectroscopic device of claim 7.

12. the multi-channel photodetector includes a detector body for detecting the plurality of light beams to be detected, and a case for accommodating the detector body; the case includes a cylindrical portion that is fixed to the adjustment portion while being in contact with the adjustment portion, and a lid portion that is provided on the cylindrical portion so as to close the cylindrical portion on the side opposite to the adjustment portion, the detector main body is sandwiched between the cylindrical portion and a lid portion when housed in the cylindrical portion, a fifth light-shielding member is provided on a contact surface between the lid portion and the detector body so as to surround the detector body; 8. The spectroscopic device of claim 7.

13. the lid portion is fixed to the cylindrical portion while being in contact with the cylindrical portion, a sixth light-shielding member in the form of a sheet is provided on a contact surface between the lid portion and the cylindrical portion so as to surround the detector body; 13. The spectroscopic device of claim 12.

14. a passage hole is formed in the case for passing a cable electrically connected to the detector body; A gap between the inner surface of the passage hole and the cable is filled with a light-blocking resin.

13. The spectroscopic device of claim 12.

15. When viewed from the arrangement direction of the holding portion and the adjusting portion, the adjusting portion has a portion that protrudes outward from the holding portion. The spectroscopic device according to any one of claims 7 to 14.

Images