Spectrometers and Spectroscopic Systems

Abstract

The present invention provides a spectrometer capable of appropriately acquiring the detection results of zero-order light reflected by a spectroscopic unit, and a spectroscopic system equipped with such a spectrometer. [Solution] The spectrometer 1 comprises a photodetector 2 having a light-passing section 2a and a spectral section 3. The photodetector 2 includes a first photodetector 21 which contains a plurality of first pixels and detects the -1st order light L1 spectrally separated by the spectral section 3 from the measurement light L reflected by the spectral section 3, and a second photodetector 22 which contains a plurality of second pixels and detects the 0th order light L0 from the measurement light L reflected by the spectral section 3. When viewed from the X-axis direction, the light-passing section 2a is arranged between the first photodetector 21 and the second photodetector 22. The spectral section 3 spectrally separates and reflects the measurement light L such that the full width at half maximum of the 0th order light L0 in the second photodetector 22 is greater than the full width at half maximum of the -1st order light L1 in the first photodetector 21, for the -1st order light L1 and 0th order light L0 of the same wavelength.

Description

Technical Field

[0001] The present invention relates to a spectroscope and a spectroscopic system.

Background Art

[0002] There is known a spectroscope including a light detection element having a light passage portion through which measurement light passes, and a spectroscopic portion that spectroscopically disperses and reflects the measurement light that has passed through the light passage portion. The light detection element includes a first light detection portion that detects diffracted light of a predetermined order that has been spectroscopically dispersed by the spectroscopic portion among the measurement light reflected by the spectroscopic portion, and a second light detection portion that detects zero-order light among the measurement light reflected by the spectroscopic portion (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the spectroscope as described above, how to effectively use the detection result obtained by the second light detection portion, that is, the detection result of the zero-order light reflected by the spectroscopic portion, is important for improving the spectroscopic accuracy of the spectroscope and expanding the applications of the spectroscope.

[0005] Therefore, an object of the present invention is to provide a spectroscope capable of appropriately obtaining the detection result of the zero-order light reflected by the spectroscopic portion, and a spectroscopic system including such a spectroscope.

Means for Solving the Problems

[0006] The spectrometer of the present invention is a spectrometer comprising: [1] a photodetector having a light-passing section through which measurement light passes; and a spectrometer that spectrally analyzes and reflects the measurement light that has passed through the light-passing section, wherein the photodetector includes a plurality of first pixels and a first photodetector that detects diffracted light of a predetermined order spectrally analyzed by the spectrometer from the measurement light reflected by the spectrometer; and a second photodetector that includes a plurality of second pixels and detects zero-order light from the measurement light reflected by the spectrometer, wherein when viewed from a first direction through which the measurement light passes through the light-passing section, the light-passing section is arranged between the first photodetector and the second photodetector in a second direction intersecting the first direction, and the spectrometer spectrally analyzes and reflects the measurement light such that the full width at half maximum of the zero-order light in the second photodetector is greater than the full width at half maximum of the diffracted light in the first photodetector for the diffracted light and the zero-order light of the same wavelength.

[0007] In the spectrometer described above, the diffracted light dispersed by the spectrometer is detected by a first photodetector containing multiple first pixels. This allows the spectrum of the measurement light to be obtained within a predetermined wavelength range. Meanwhile, zero-order light incident on the second photodetector, where the full width at half maximum of the zero-order light in the second photodetector is greater than the full width at half maximum of the diffracted light in the first photodetector, is detected by a second photodetector containing multiple second pixels. This suppresses the saturation of the charge generated in response to the incidence of zero-order light in each of the multiple second pixels, allowing for accurate acquisition of, for example, the peak position of the light intensity of the zero-order light, the amount of light of the zero-order light, etc. Therefore, the spectrometer described above allows for appropriate acquisition of the detection results of the zero-order light reflected by the spectrometer.

[0008] The spectrometer of the present invention may also be [2] "the spectrometer described in [1] above, wherein the spectroscopic unit spectrally analyzes and reflects the measurement light such that the full width at half maximum of the diffracted light and the zeroth-order light having the same wavelength as the diffracted light and the zeroth-order light in the second photodetector is at least twice the full width at half maximum of the diffracted light in the first photodetector." With this spectrometer, it is possible to reliably suppress the saturation of the charge generated in response to the incidence of zeroth-order light in each of the plurality of second pixels.

[0009] The spectrometer of the present invention may also be [3] "the spectrometer according to [1] or [2] above, wherein the spectroscopic unit spectrally analyzes and reflects the measurement light such that the amount of shift in the focusing position of the zeroth-order light relative to the second photodetector is greater than the maximum amount of shift in the focusing position of the diffracted light relative to the first photodetector." With this spectrometer, it is possible to reliably suppress the saturation of the charge generated in response to the incidence of zeroth-order light in each of the plurality of second pixels.

[0010] The spectrometer of the present invention may also be [4] "the spectrometer described in [3] above, wherein the spectroscopic unit spectrally analyzes and reflects the measurement light such that the amount of shift of the collection position of the zeroth-order light relative to the second photodetector is five times or more the maximum value of the amount of shift of the collection position of the diffracted light relative to the first photodetector." With this spectrometer, it is possible to reliably suppress the saturation of the charge generated in response to the incidence of zeroth-order light in each of the plurality of second pixels.

[0011] The spectrometer of the present invention may also be [5] "a spectrometer according to any one of [1] to [4] above, wherein, when viewed from the first direction, the light-transmitting section, the first photodetector, and the second photodetector are each arranged with a first straight line parallel to the second direction as their centerline." With this spectrometer, a configuration in which diffracted light is incident on the first photodetector and zero-order light is incident on the second photodetector can be easily and reliably realized.

[0012] The spectrometer of the present invention may also be [6] "the spectrometer described in [5] above, wherein the width of the light-transmitting portion in a third direction intersecting both the first and second directions is greater than the width of the first photodetector in the third direction and greater than the width of the second photodetector in the third direction." With this spectrometer, even if the incident position of the diffracted light on the first photodetector is shifted in the third direction, the diffracted light can be received over the entire width of the first photodetector in the third direction. Similarly, even if the incident position of the zero-order light on the second photodetector is shifted in the third direction, the zero-order light can be received over the entire width of the second photodetector in the third direction.

[0013] The spectrometer of the present invention may also be [7] "the spectrometer according to any one of [1] to [6] above, wherein the photodetector further comprises a circuit section electrically connected to each of the first and second photodetectors, and when viewed from the first direction, the light-passing section, the first photodetector, and the second photodetector are offset to one side in a third direction that intersects both the first and second directions, and the circuit section is offset to the other side in the third direction." The spectrometer allows for simplification of the structure of the photodetector and optimization of the layout of each part in the photodetector.

[0014] The spectrometer of the present invention may also be [8] "a spectrometer according to any one of [1] to [7] above, wherein the distance between the light-transmitting section and the first photodetector is smaller than the distance between the light-transmitting section and the second photodetector." According to this spectrometer, diffracted light on the shorter wavelength side can be detected.

[0015] The spectrometer of the present invention may also be [9] "a spectrometer according to any one of [1] to [7] above, wherein the distance between the light-transmitting section and the first photodetector is greater than the distance between the light-transmitting section and the second photodetector." According to this spectrometer, diffracted light on the longer wavelength side can be detected.

[0016] The spectrometer of the present invention may also be

[10] "a spectrometer according to any one of [1] to [9] above, further comprising a support member that supports at least the spectroscopic section such that a space is formed between the photodetector and the spectroscopic section, and has a curved surface formed in a concave shape on the side opposite to the photodetector, wherein the spectroscopic section is formed on the curved surface." With this spectrometer, a configuration in which diffracted light is incident on the first photodetector and zeroth-order light is incident on the second photodetector can be easily and reliably realized.

[0017] The spectrometer of the present invention may also be

[11] "the spectrometer described in

[10] above, wherein the curved surface is formed in a concave shape on the side opposite to the photodetector with a second straight line parallel to the first direction as its center line, and the center of the light-passing portion is offset in the second direction from the second straight line." With this spectrometer, a configuration in which diffracted light is incident on the first photodetector and zero-order light is incident on the second photodetector can be realized more easily and reliably.

[0018] The spectrometer of the present invention may also be

[12] "a spectrometer according to any one of [1] to [9] above, further comprising a light-transmitting member that supports at least the spectroscopic section between the photodetector and the spectroscopic section and has a curved surface formed convexly on the side opposite to the photodetector, wherein the spectroscopic section is formed on the curved surface." With this spectrometer, a configuration in which diffracted light is incident on the first photodetector and zeroth-order light is incident on the second photodetector can be easily and reliably realized.

[0019] The spectrometer of the present invention may also be the spectrometer described in

[12] above, in which the curved surface is formed convex on the side opposite to the photodetector with a second straight line parallel to the first direction as its center line, and the center of the light-passing portion is offset in the second direction from the second straight line. With this spectrometer, a configuration in which diffracted light is incident on the first photodetector and zero-order light is incident on the second photodetector can be realized more easily and reliably.

[0020] The spectroscope of the present invention may also be "

[14] the spectroscope according to any one of [1] to

[13] above, further comprising a filter disposed on the optical path of the zero-order light from the spectroscopic unit to the second light detection unit and cutting light in the same wavelength range as the diffracted light". According to this spectroscope, while acquiring the spectrum of the measurement light in a predetermined wavelength range, it is possible to detect the measurement light outside the predetermined wavelength range.

[0021] The spectroscopic system of the present invention is "

[15] a spectroscopic system comprising the spectroscope according to any one of [1] to

[13] above and a processing device electrically connected to each of the first light detection unit and the second light detection unit".

[0022] According to the above spectroscopic system, the detection result of the zero-order light appropriately acquired by the spectroscope can be effectively utilized.

[0023] The spectroscopic system of the present invention may also be "

[16] the spectroscopic system according to

[15] above, wherein the processing device corrects the relationship between the wavelength and the incident position of the diffracted light incident on the first light detection unit based on the detection result acquired by the second light detection unit". According to this spectroscopic system, for example, even if a deviation occurs in the relationship between the wavelength and the incident position of the diffracted light due to deformation (expansion or contraction) of each part caused by a change in the environmental temperature, heat generation of the light detection element, etc., the deviation can be corrected.

[0024] The spectroscopic system of the present invention may also be "

[17] the spectroscopic system according to

[15] or

[16] above, wherein the processing device acquires at least one of the incident angle and the numerical aperture of the measurement light incident on the spectroscopic unit through the light passing unit based on the detection result acquired by the second light detection unit". According to this spectroscopic system, it is possible to grasp whether the incident angle and the numerical aperture of the measurement light in the light passing unit are appropriate.

[0025] The spectroscopic system of the present invention may be "

[18] the spectroscopic system according to any one of

[15] to

[17] above, wherein the processing device obtains the diffraction efficiency of the spectroscopic unit based on the detection results obtained by each of the first photodetector and the second photodetector when light of a predetermined wavelength included in the diffracted light enters the spectroscopic unit through the light passage unit". According to this spectroscopic system, it is possible to grasp whether the state of the spectroscopic unit is appropriate.

[0026] The spectroscope of the present invention may be "a photodetector having a light passage unit through which measurement light passes, and a spectroscopic unit that spectrally disperses and reflects the measurement light that has passed through the light passage unit. The photodetector includes a plurality of first pixels, and a first photodetector that detects diffracted light of a predetermined order spectrally dispersed by the spectroscopic unit among the measurement light reflected by the spectroscopic unit. The photodetector also includes a plurality of second pixels and a second photodetector that detects zero-order light among the measurement light reflected by the spectroscopic unit. When viewed from a first direction in which the measurement light passes through the light passage unit, the light passage unit is disposed between the first photodetector and the second photodetector in a second direction that intersects the first direction. The spectroscopic unit spectrally disperses and reflects the measurement light such that the deviation amount of the condensing position of the zero-order light with respect to the second photodetector is greater than the maximum value of the deviation amount of the condensing position of the diffracted light with respect to the first photodetector". According to this spectroscope, for the same reason as the spectroscope described in [1] above, it is possible to appropriately obtain the detection result of the zero-order light reflected by the spectroscopic unit. Note that at least one configuration described in [1], [2], and [4] to

[14] above can be combined in this spectroscope.

Effects of the Invention

[0027] According to the present invention, it is possible to provide a spectroscope that can appropriately obtain the detection result of the zero-order light reflected by the spectroscopic unit, and a spectroscopic system including such a spectroscope.

Brief Description of the Drawings

[0028] [Figure 1]This is a cross-sectional view of an example of a spectrometer. [Figure 2] Figure 1 shows a cross-sectional view of the spectrometer along the line II-II. [Figure 3] Figure 1 is a bottom view of the photodetector element. [Figure 4] Figure 1 is a side view of the photodetector and spectrometer shown. [Figure 5] Figure 1 is a plan view of the photodetector and spectrometer shown. [Figure 6] Figure 1 is a graph showing the relationship between pixel number and light intensity in the photodetector element. [Figure 7] This graph shows the full width at half maximum (FWHM) of the diffracted light in the first photodetector and the FWHM of the zeroth-order light in the second photodetector. [Figure 8] This figure shows the amount of shift in the collection position of the diffracted light relative to the first photodetector. [Figure 9] Figure 1 is a bottom view of the photodetector element. [Figure 10] Figure 1 is a diagram illustrating the configuration of a spectroscopic system equipped with a spectrometer. [Figure 11] Figure 1 is a side view of the photodetector and spectrometer shown. [Figure 12] This is a cross-sectional view of a modified spectrometer. [Figure 13] This is a bottom view of a modified photodetector element. [Figure 14] This is a side view of the photodetector element and spectroscopic section of a modified spectrometer. [Modes for carrying out the invention]

[0029] An example of the present invention will be described in detail below with reference to the drawings. In each figure, the same or corresponding parts are denoted by the same reference numerals, and redundant explanations are omitted. [Spectrometer Configuration]

[0030] As shown in Figures 1 and 2, the spectrometer 1 comprises a photodetector 2, a spectral section 3, and a plurality of support members 4 and 5. The photodetector 2 has a light-passing section 2a through which the measurement light L passes. The spectral section 3 spectrally analyzes and reflects the measurement light L that has passed through the light-passing section 2a. The support member 4 supports the spectral section 3. The support member 5 is arranged on the support member 4 and supports the photodetector 2. Hereinafter, the direction in which the measurement light L passes through the light-passing section 2a will be referred to as the Z-axis direction (first direction). Furthermore, one direction perpendicular to the Z-axis direction will be referred to as the X-axis direction (second direction intersecting the first direction), and the direction perpendicular to both the Z-axis direction and the X-axis direction will be referred to as the Y-axis direction (third direction intersecting both the first and second directions).

[0031] The photodetector element 2, the spectroscopic unit 3, and the multiple support members 4 and 5 are housed in a package 6. The package 6 has a stem 61 and a cap 62. The stem 61 is formed, for example, from metal in the shape of a rectangular plate. The cap 62 is formed, for example, from metal in the shape of a rectangular parallelepiped box. The stem 61 and the cap 62 are airtightly joined at the flange portion 61a of the stem 61 and the flange portion 62a of the cap 62. The length of one side of the package 6 is, for example, about 10 to 20 mm. Note that the stem 61 and the cap 62 do not necessarily have to be joined to an airtight seal.

[0032] A light-entry aperture 62c is formed in the wall portion 62b of the cap 62 that faces the stem 61 in the Z-axis direction, allowing measurement light L to be incident into the package 6 from outside. The shape of the light-entry aperture 62c when viewed from the Z-axis direction is, for example, circular. A window member 63 is hermetically joined to the inner surface of the wall portion 62b so as to cover the light-entry aperture 62c. The window member 63 transmits the measurement light L. The window member 63 is formed, for example, from glass in the shape of a circular or rectangular plate. The window member 63 may be coated with an AR (Anti-Reflection) coating. The window member 63 may have a filter function that transmits only light within a predetermined wavelength range. Note that the cap 62 and the window member 63 do not need to be joined in a completely hermetically sealed manner.

[0033] Multiple lead pins 7 are fixed to the stem 61. Multiple through holes 61b are formed in the stem 61, and each lead pin 7 extends in the Z-axis direction through each through hole 61b. Each lead pin 7 is fixed to each through hole 61b via a hermetic sealing member (for example, low-melting-point glass having electrical insulation and light-shielding properties). The multiple through holes 61b are aligned along each of a pair of edges of the stem 61 that face each other in the Y-axis direction.

[0034] The support member 4 is positioned on the inner surface 61c of the stem 61. The support member 4 has a surface 4a on the window member 63 side and a surface 4b on the stem 61 side. Surface 4a of the support member 4 includes a concave curved surface 4c. Surface 4b of the support member 4 is in contact with the inner surface 61c of the stem 61, but is not fixed to the inner surface 61c of the stem 61. The support member 4 is formed in the shape of a rectangular plate from, for example, silicone, resin, ceramic, glass, etc.

[0035] The spectroscopic section 3 is composed of a molded layer 31 and a reflective film 32. The molded layer 31 is formed in a film-like manner along the curved surface 4c of the support member 4. A grating pattern 3a is formed on the molded layer 31. The grating pattern 3a is, for example, a blazed grating pattern, a binary grating pattern, a holographic grating pattern, etc. The grating pattern 3a has a plurality of grating grooves aligned in the X-axis direction when viewed from the Z-axis direction. Each grating groove extends in the Y-axis direction when viewed from the Z-axis direction. The reflective film 32 is formed in a film-like manner along the grating pattern 3a. The molded layer 31 is formed, for example, by photocuring or thermocuring of a resin. The reflective film 32 is formed, for example, by metal deposition onto the grating pattern 3a.

[0036] The support member 5 has a top wall portion 51, a pair of side wall portions 52 and 53, and a pair of protrusions 54. The top wall portion 51 is positioned between the spectrometer 3 and the window member 63 in the Z-axis direction. The top wall portion 51 has a surface 51a on the spectrometer 3 side and a surface 51b on the window member 63 side. The pair of side wall portions 52 and 53 are positioned between the support member 4 and the top wall portion 51 and face each other in the X-axis direction. The pair of protrusions 54 protrude from the top wall portion 51 on both sides in the Y-axis direction. Each protrusion 54 extends in the X-axis direction. Each protrusion 54 has a surface 54a on the side opposite to the stem 61 and a surface 54b on the side of the stem 61. The surface 54a of each protrusion 54 is located on the same plane as the surface 51b of the top wall portion 51. The top wall portion 51, the pair of side wall portions 52 and 53, and the pair of protruding portions 54 are integrally formed from, for example, resin, ceramic, or the like.

[0037] A light-passing aperture 51c is formed in the top wall portion 51 to allow measurement light L to pass through. The shape of the light-passing aperture 51c when viewed from the Z-axis direction is, for example, rectangular. The light-passing aperture 51c faces the light-entry aperture 62c of the cap 62 in the Z-axis direction. The light-passing aperture 51c is widened toward the light-entry aperture 62c in the X-axis direction and the Y-axis direction, respectively. When viewed from the Z-axis direction, the light-entry aperture 62c encompasses the entirety of the light-passing aperture 51c.

[0038] The side wall portion 52 is located on one side of the spectrometer 3 in the X-axis direction. The side wall portion 53 is located on the other side of the spectrometer 3 in the X-axis direction. The width of the side wall portion 52 in the X-axis direction is greater than the width of the side wall portion 53 in the X-axis direction. A pair of protrusions 52b are provided on the inner surface 52a of the side wall portion 52. Each protrusion 52b extends in the Z-axis direction. A pair of protrusions 53b are provided on the inner surface 53a of the side wall portion 53. Each protrusion 53b extends in the Z-axis direction. The bottom surface 52c of the side wall portion 52 is fixed to the surface 4a of the support member 4, for example, by adhesive. The bottom surface 53c of the side wall portion 53 is in contact with the surface 4a of the support member 4, but is not fixed to the surface 4a of the support member 4. In the spectrometer 1, the support of the support member 5 on the support member 4 is stabilized by the pair of protrusions 52b and the pair of protrusions 53b.

[0039] The photodetector 2 has a semiconductor substrate 20. The semiconductor substrate 20 is formed in the shape of a rectangular plate, for example, from silicon. The semiconductor substrate 20 has a surface 20a on which the first photodetector 21 and the second photodetector 22 are provided, and a surface 20b on the opposite side. Surface 20a of the semiconductor substrate 20 faces the spectral section 3 across space. Surface 20b of the semiconductor substrate 20 is fixed to the surface 51a of the top wall 51, for example, by adhesive. The photodetector 2 is electrically connected to wiring (not shown) provided on the support member 5 at the top wall 51.

[0040] The light-transmitting portion 2a is a slit formed in the semiconductor substrate 20. When viewed from the Z-axis direction, the shape of the light-transmitting portion 2a is, for example, a rectangle with the Y-axis direction as the longer side. The light-transmitting portion 2a is located between the light-transmitting aperture 51c of the top wall portion 51 and the spectral portion 3 in the Z-axis direction, and is adjacent to the light-transmitting aperture 51c of the top wall portion 51. The light-transmitting portion 2a is widened toward the light-transmitting aperture 51c in the X-axis direction and the Y-axis direction, respectively. When viewed from the Z-axis direction, the light-transmitting aperture 51c includes the entirety of the light-transmitting portion 2a.

[0041] The first photodetector 21 is positioned on the side wall 53 side in the X-axis direction relative to the light-passing section 2a. The second photodetector 22 is positioned on the side wall 52 side in the X-axis direction relative to the light-passing section 2a. In other words, when viewed from the Z-axis direction, the light-passing section 2a is positioned between the first photodetector 21 and the second photodetector 22 in the X-axis direction. The first photodetector 21 detects the -1st order light (diffracted light of a predetermined order: m-th order diffracted light (m is an integer excluding 0)) L1 of a predetermined wavelength range that has been spectrally separated by the spectrometer 3 from the measurement light L reflected by the spectrometer 3. The second photodetector 22 detects the 0th order light L0 of the measurement light L reflected by the spectrometer 3. Hereinafter, the -1st order light L1 of a predetermined wavelength range that has been spectrally separated by the spectrometer 3 and detected by the first photodetector 21 will simply be referred to as "-1st order light L1".

[0042] Each protrusion 54 has multiple through holes 54c formed within it. The multiple through holes 54c are aligned in the X-axis direction within each protrusion 54. The ends of each lead pin 7 are positioned within each through hole 54c, and the stoppers 71 provided on each lead pin 7 are in contact with the surface 54b of each protrusion 54. This positions the mutually fixed support members 4 and 5 relative to the package 6. A predetermined number of the multiple lead pins 7 are electrically connected to the wiring provided on the support member 5 within each protrusion 54.

[0043] In the spectrometer 1 configured as described above, the measurement light L sequentially passes through the light entry aperture 62c of the package 6, the window member 63, the light passing aperture 51c of the top wall 51, and the light passing portion 2a of the photodetector 2, before entering the spectral unit 3. Then, the -1st order light L1 of the measurement light L reflected by the spectral unit 3 enters the first photodetector 21 of the photodetector 2, and the incident -1st order light L1 is detected by the first photodetector 21. On the other hand, the 0th order light L0 of the measurement light L reflected by the spectral unit 3 enters the second photodetector 22 of the photodetector 2, and the incident 0th order light L0 is detected by the second photodetector 22. At this time, the input and output of electrical signals to the first photodetector 21 and the second photodetector 22 are performed via a predetermined number of lead pins 7 electrically connected to the wiring provided on the support member 5.

[0044] In the spectrometer 1, the support members 4 and 5, which are fixed to each other, are positioned relative to the package 6 by a plurality of lead pins 7. In the support members 4 and 5, the surface 4b of support member 4 is only in contact with the inner surface 61c of the stem 61, and is not fixed to the inner surface 61c of the stem 61. Similarly, the bottom surface 53c of the side wall portion 53 is only in contact with the surface 4a of support member 4, and is not fixed to the surface 4a of support member 4. As a result, in the spectrometer 1, even if deformation (expansion or contraction) of each part occurs due to, for example, changes in ambient temperature or heat generation of the photodetector element, the relative positions of the light-passing portion 2a, the spectral portion 3, the first photodetector portion 21, and the second photodetector portion 22 are less likely to shift. [Configuration of the photodetector element]

[0045] As shown in Figure 3, the photodetector 2 further includes a circuit section 23 in addition to the first photodetector 21 and the second photodetector 22. The circuit section 23 is electrically connected to the first photodetector 21 and the second photodetector 22, respectively. The first photodetector 21 and the second photodetector 22 are electrically connected to wiring provided on the support member 5 via the circuit section 23. The circuit section 23 performs operation control (e.g., control of exposure timing and readout timing), output signal processing (e.g., conversion from analog signal to digital signal), etc., for the first photodetector 21 and the second photodetector 22, respectively. The photodetector 2 is, for example, a CMOS image sensor. The photodetector 2 may be other image sensors (e.g., a CCD image sensor, etc.).

[0046] When viewed from the Z-axis direction, the light-transmitting section 2a, the first photodetector 21, and the second photodetector 22 are offset to one side in the Y-axis direction, and the circuit section 23 is offset to the other side in the Y-axis direction. When viewed from the Z-axis direction, each of the light-transmitting section 2a, the first photodetector 21, and the second photodetector 22 is centered on a first straight line A1 parallel to the X-axis direction. The first photodetector 21 includes a plurality of first pixels 21a. The plurality of first pixels 21a are arranged in a line on the first straight line A1. The second photodetector 22 includes a plurality of second pixels 22a. The plurality of second pixels 22a are arranged in a line on the first straight line A1.

[0047] The width W of the light-transmitting section 2a in the Y-axis direction is greater than the width W1 of the first photodetector 21 in the Y-axis direction. The width W of the light-transmitting section 2a in the Y-axis direction is greater than the width W2 of the second photodetector 22 in the Y-axis direction. The widths W1 of the first photodetector 21 and W2 of the second photodetector 22 are approximately equal to each other. The widths W1 of the first photodetector 21 and W2 of the second photodetector 22 may be different to each other. The distance D1 between the light-transmitting section 2a and the first photodetector 21 is less than the distance D2 between the light-transmitting section 2a and the second photodetector 22. Note that the width W of the light-transmitting section 2a in the Y-axis direction is the minimum value if the width of the light-transmitting section 2a in the Y-axis direction is changing. For example, if the light-transmitting portion 2a is widened toward the opposite side of the surface 20a of the semiconductor substrate 20 in both the X-axis and Y-axis directions, as shown by the solid and dashed lines in Figure 3, then the width W of the light-transmitting portion 2a in the Y-axis direction is the "width of the light-transmitting portion 2a in the Y-axis direction" on the surface 20a of the semiconductor substrate 20. Also, the distance D1 between the light-transmitting portion 2a and the first photodetector 21 is the distance between the light-emitting end of the light-transmitting portion 2a and the first photodetector 21, and is the distance in the X-axis direction. The distance D2 between the light-transmitting portion 2a and the second photodetector 22 is the distance between the light-emitting end of the light-transmitting portion 2a and the second photodetector 22, and is the distance in the X-axis direction. [Positional relationships of each part]

[0048] As shown in Figures 4 and 5, the spectral section 3 is formed on a concave curved surface 4c of the support member 4. The spectral section 3 is formed in a film-like manner along the curved surface 4c. The support member 4 supports the spectral section 3 such that a space is formed between the photodetector 2 and the spectral section 3. In the spectrometer 1, the optical paths of the measurement light L, the -1st order light L1, and the 0th order light L0 are formed in space between the photodetector 2 and the spectral section 3. The curved surface 4c is concave on the side opposite to the photodetector 2, with a second straight line A2 parallel to the Z-axis as its centerline. The second straight line A2 intersects with the first straight line A1. The center C of the light-passing section 2a is offset from the second straight line A2 in the X-axis direction. The second straight line A2 is offset toward the second photodetector 22 side relative to the center C of the light-passing section 2a. The second straight line A2 passes between the light-passing section 2a and the second photodetector 22. In Figure 5, the curved surface 4c and the spectral section 3 are shown as extending beyond the photodetector 2, indicated by dashed lines. However, in the spectrometer 1, most of the portions of the curved surface 4c and the spectral section 3 that extend beyond the photodetector 2 do not exist. [Incident state of -1st order light and 0th order light]

[0049] Figure 6 is a graph showing the relationship between the pixel number and light intensity in the photodetector 2. This graph shows the results when light of multiple wavelengths is incident on the spectrometer 1 as emission lines (i.e., for each wavelength). On the horizontal axis, "Pixel Number," 1 to 32 correspond to multiple second pixels 22a arranged in a line on the first line A1, and 33 to 288 correspond to multiple first pixels 21a arranged in a line on the first line A1.

[0050] As shown in Figure 6, in the range 33-288 (i.e., in the first photodetector 21 which includes multiple first pixels 21a), light of multiple wavelengths appears in multiple dispersed regions, with each region being narrow in width and having a high peak value of light intensity. This indicates that "the -1st order light L1 of each wavelength is incident on the first photodetector 21" and "therefore, the spectrum of the measurement light L can be acquired with high resolution in a predetermined wavelength range."

[0051] On the other hand, in 1 to 32 (i.e., in the second photodetector 22 which includes multiple second pixels 22a), light of multiple wavelengths appears in the same region, the width of the region is wide and the peak value of the light intensity in the region is low. This indicates that "the 0th order light L0 of each wavelength is incident on the second photodetector 22 in a defocused state (defocused compared to the -1st order light L1 incident on the first photodetector 21)", "even when the measurement light L includes light of each wavelength, the charge generated in each second pixel 22a in response to the incidence of the 0th order light L0 is less likely to reach a saturation state", and "as a result, for example, the peak position of the light intensity of the 0th order light L0, the amount of light of the 0th order light L0, etc. can be obtained with high accuracy".

[0052] Figure 7(a) is a graph showing the full width at half maximum (FWHM) of the -1st order light L1 in the first photodetector 21, and Figure 7(b) is a graph showing the full width at half maximum (FWHM) of the 0th order light L0 in the second photodetector 22. As shown in Figures 7(a) and (b), when comparing the -1st order light L1 and 0th order light L0 of the same wavelength, the FWHM F0 of the 0th order light L0 in the second photodetector 22 is larger than the FWHM F1 of the -1st order light L1 in the first photodetector 21. The FWHM F1 is the FWHM (full width at half maximum) of the -1st order light L1 for each wavelength in the direction in which the first photodetector 21 and the second photodetector 22 are aligned (i.e., the X-axis direction), and the FWHM F0 is the FWHM of the 0th order light L0 for each wavelength in the direction in which the first photodetector 21 and the second photodetector 22 are aligned. With respect to the position of the -1st order light L1 in the incident direction, the full width at half maximum F1 is the FWHM of the -1st order light L1 at each wavelength on the light-receiving surface 210 on the incident side of the first photodetector 21, and with respect to the position of the 0th order light L0 in the incident direction, the full width at half maximum F0 is the FWHM of the 0th order light L0 at each wavelength on the light-receiving surface 220 on the incident side of the second photodetector 22. This is independent of whether the photodetector 2 is a surface-incident photodetector (for example, a photodetector where the light-receiving surface 210 of the first photodetector 21 and the light-receiving surface 220 of the second photodetector 22 are located on the surface 20a of the semiconductor substrate 20) or a back-incident photodetector (for example, a photodetector where the light-receiving surface 210 of the first photodetector 21 and the light-receiving surface 220 of the second photodetector 22 are located inside the semiconductor substrate 20). The respective half-widths F1 and F0 can be obtained from the light intensity signals (shown as solid lines in Figures 7(a) and (b)) obtained by applying Gaussian fitting to the detected light intensity signals (shown as dashed lines in Figures 7(a) and (b)). Note that the horizontal and vertical scales of the graphs shown in Figures 7(a) and (b) are different from each other.

[0053] The spectrometer 3 spectrally analyzes and reflects the measurement light L such that the full width at half maximum (F0) of the 0th-order light L0 in the second photodetector 22 is greater than the full width at half maximum (F1) of the -1st-order light L1 in the first photodetector 21, for the -1st-order light L1 and 0th-order light L0, which have the same wavelength. In the spectrometer 1, the spectrometer 3 spectrally analyzes and reflects the measurement light L such that the full width at half maximum (F0) of the 0th-order light L0 in the second photodetector 22 is more than twice (for example, more than three times) the full width at half maximum (F1) of the -1st-order light L1 in the first photodetector 21, for the -1st-order light L1 and 0th-order light L0, which have the same wavelength. As an example, the full width at half maximum (F1) of the -1st-order light L1 in the first photodetector 21 is about 50 μm, and the full width at half maximum (F0) of the 0th-order light L0 in the second photodetector 22 is about 100 to 500 μm.

[0054] Figure 8 shows the amount of shift in the focusing position P1 of the -1st order light L1 relative to the first photodetector 21. As shown in Figure 8, although the spectrometer 3 causes the -1st order light L1 of each wavelength to be incident on the first photodetector 21 in a focused state, strictly speaking, the focusing position P1 of the -1st order light L1 of each wavelength is shifted from the light-receiving surface 210 of the first photodetector 21. For each wavelength of -1st order light L1, the "amount of shift from the light-receiving surface 210 of the first photodetector 21" in the direction along the optical axis of the -1st order light L1 of each wavelength is called the "amount of shift S1 of the focusing position P1 of the -1st order light L1 relative to the first photodetector 21". As shown in Figure 4, in the spectrometer 1, the focusing position P0 of the 0th order light L0 of each wavelength is located behind the light-receiving surface 220 of the second photodetector 22 in the direction of propagation of the 0th order light L0 of each wavelength. In other words, the focusing position P0 of the zero-order light L0 for each wavelength is offset from the light-receiving surface 220 of the second photodetector 22. For each wavelength of zero-order light L0, the "amount of offset from the light-receiving surface 220 of the second photodetector 22" in the direction along the optical axis of the zero-order light L0 for each wavelength is called the "amount of offset S0 of the focusing position P0 of the zero-order light L0 relative to the second photodetector 22". The amount of offset S0 of the focusing position P0 of the zero-order light L0 relative to the second photodetector 22 is substantially equal for each wavelength of zero-order light L0.

[0055] The spectrometer 3 spectrally analyzes and reflects the measurement light L such that the amount of shift S0 of the focusing position P0 of the 0th-order light L0 relative to the second photodetector 22 is greater than the maximum value of the amount of shift S1 of the focusing position P1 of the -1st-order light L1 relative to the first photodetector 21. In the spectrometer 1, the spectrometer 3 spectrally analyzes and reflects the measurement light L such that the amount of shift S0 of the focusing position P0 of the 0th-order light L0 relative to the second photodetector 22 is 5 times or more (for example, 10 times or more) the maximum value of the amount of shift S1 of the focusing position P1 of the -1st-order light L1 relative to the first photodetector 21. As an example, the maximum value of the amount of shift S1 of the focusing position P1 of the -1st-order light L1 relative to the first photodetector 21 is about 0.08 mm, and the amount of shift S0 of the focusing position P0 of the 0th-order light L0 relative to the second photodetector 22 is about 0.4 to 1.2 mm. In the spectrometer 1, the amount of shift S0 of the focusing position P0 of the 0th-order light L0 relative to the second photodetector 22 is greater than the maximum value of the amount of shift S1 of the focusing position P1 of the -1st-order light L1 relative to the first photodetector 21. As a result, the spot diameter of the 0th-order light L0 on the light-receiving surface 220 of the second photodetector 22 is greater than the spot diameter of the -1st-order light L1 on the light-receiving surface 210 of the first photodetector 21. Consequently, the full width at half maximum F0 of the 0th-order light L0 in the second photodetector 22 is greater than the full width at half maximum F1 of the -1st-order light L1 in the first photodetector 21. [The function and effects of a spectrometer]

[0056] In the spectrometer 1, the -1st order light L1 spectrally separated by the spectrometer 3 is detected by the first photodetector 21, which includes a plurality of first pixels 21a. This allows the spectrum of the measurement light L to be obtained within a predetermined wavelength range. Meanwhile, the 0th order light L0 incident on the second photodetector 22, where the full width at half maximum F0 of the 0th order light L0 in the second photodetector 22 is greater than the full width at half maximum F1 of the -1st order light L1 in the first photodetector 21, is detected by the second photodetector 22, which includes a plurality of second pixels 22a. Here, the spectrometer 3 spectrally separates and reflects the measurement light L such that the full width at half maximum F0 of the 0th order light L0 in the second photodetector 22 is at least twice the full width at half maximum F1 of the -1st order light L1 in the first photodetector 21, for the -1st order light L1 and 0th order light L0 of the same wavelength. As a result, the charge generated in response to the incidence of zero-order light L0 in each of the multiple second pixels 22a is prevented from reaching a saturation state, so that, for example, the peak position of the light intensity of the zero-order light L0, the amount of light of the zero-order light L0, etc. can be obtained with high accuracy. Therefore, with the spectrometer 1, the detection results of the zero-order light L0 reflected by the spectroscopic unit 3 can be appropriately obtained.

[0057] In the spectrometer 1, the spectroscopic unit 3 spectrally analyzes and reflects the measurement light L such that the amount of shift S0 of the focusing position P0 of the 0th-order light L0 relative to the second photodetector 22 is greater than the maximum value of the amount of shift S1 of the focusing position P1 of the -1st-order light L1 relative to the first photodetector 21. Here, the spectroscopic unit 3 spectrally analyzes and reflects the measurement light L such that the amount of shift S0 of the focusing position P0 of the 0th-order light L0 relative to the second photodetector 22 is 5 times or more the maximum value of the amount of shift S1 of the focusing position P1 of the -1st-order light L1 relative to the first photodetector 21. This reliably prevents the charge generated in response to the incidence of the 0th-order light L0 in each of the multiple second pixels 22a from reaching a saturation state.

[0058] In the spectrometer 1, when viewed from the Z-axis direction, the light-transmitting section 2a, the first photodetector 21, and the second photodetector 22 are each arranged with a first straight line A1 parallel to the X-axis direction as their centerline. This makes it easy and reliable to realize a configuration in which -1st-order light L1 is incident on the first photodetector 21 and 0th-order light L0 is incident on the second photodetector 22.

[0059] In spectrometer 1, the width W of the light-passing section 2a in the Y-axis direction is greater than the width W1 of the first photodetector 21 in the Y-axis direction, and greater than the width W2 of the second photodetector 22 in the Y-axis direction. As a result, even if the incident position of the -1st-order light L1 on the first photodetector 21 shifts in the Y-axis direction, as shown in Figure 9(b) compared to the state shown in Figure 9(a), the -1st-order light L1 can be received across the entire width W1 of the first photodetector 21 in the Y-axis direction. Similarly, even if the incident position of the 0th-order light L0 on the second photodetector 22 shifts in the Y-axis direction, the 0th-order light L0 can be received across the entire width W2 of the second photodetector 22 in the Y-axis direction.

[0060] In the spectrometer 1, the light-transmitting section 2a, the first photodetector section 21, and the second photodetector section 22 are offset to one side in the Y-axis direction, while the circuit section 23 is offset to the other side in the Y-axis direction. This simplifies the structure of the photodetector section 2 and optimizes the layout of each part in the photodetector section 2.

[0061] In the spectrometer 1, the distance D1 between the light-transmitting section 2a and the first photodetector 21 is smaller than the distance D2 between the light-transmitting section 2a and the second photodetector 22. This allows for the detection of -1st order light L1 on the shorter wavelength side.

[0062] In the spectrometer 1, the spectral section 3 is formed on a concave curved surface 4c on the side opposite to the photodetector 2, and the support member 4 supports the spectral section 3 so that a space is formed between the photodetector 2 and the spectral section 3. This makes it easy and reliable to realize a configuration in which the -1st order light L1 is incident on the first photodetector 21 and the 0th order light L0 is incident on the second photodetector 22.

[0063] In the spectrometer 1, the curved surface 4c is formed concave on the opposite side from the photodetector 2, with the second straight line A2, which is parallel to the Z-axis direction, as its centerline, and the center C of the light-passing section 2a is offset from the second straight line A2 in the X-axis direction. This makes it easier and more reliable to realize a configuration in which the -1st order light L1 is incident on the first photodetector 21 and the 0th order light L0 is incident on the second photodetector 22. [Spectroscopic System]

[0064] As shown in Figure 10, the spectroscopic system 100 comprises the spectrometer 1 described above and the processing unit 10. The processing unit 10 is electrically connected to the first photodetector 21 and the second photodetector 22, respectively, via the circuit unit 23. The processing unit 10 is, for example, a computer device. In the spectroscopic system 100, the signals output from each second pixel 22a of the second photodetector 22 are added together by binning in the processing unit 10. Alternatively, the signals output from each second pixel 22a of the second photodetector 22 may be added together by binning in the circuit unit 23 of the photodetector 2.

[0065] The processing unit 10 corrects the relationship between the wavelength and incident position of the -1st order light L1 incident on the first photodetector 21 based on the detection results obtained by the second photodetector 22. The incident position of the 0th order light L0 in the second photodetector 22 does not change with respect to wavelength. Therefore, if the peak position of the light intensity of the 0th order light L0 shifts in the X-axis direction, the processing unit 10 can assume that the incident position of the -1st order light L1 in the first photodetector 21 has also shifted in the X-axis direction, and correct the relationship between the wavelength and incident position of the -1st order light L1.

[0066] The processing device 10 acquires at least one of the incident angle and numerical aperture of the measurement light L incident on the spectroscopic unit 3 via the light-passing unit 2a, based on the detection result acquired by the second photodetector 22. For example, as shown in Figure 11(a), when the measurement light L, which is parallel light, is incident on the light-passing unit 2a such that its optical axis is parallel to the Z-axis direction, the measurement light L is reflected by the spectroscopic unit 3, causing the -1st order light L1 to be incident on the first photodetector 21 and the 0th order light L0 to be incident on the second photodetector 22. Next, as shown in Figure 11(b), when the measurement light L, which is parallel light, is incident on the light-passing unit 2a such that its optical axis is tilted with respect to the Z-axis direction, the measurement light L is reflected by the spectroscopic unit 3, causing the -1st order light L1 to be incident on the first photodetector 21 and the 0th order light L0 to be incident on the second photodetector 22. In this state, the incident position of the -1st order light L1 incident on the first photodetector 21 in the focused state does not change, but the incident position of the 0th order light L0 incident on the second photodetector 22 in the defocused state changes significantly. Therefore, the processing device 10 can obtain the incident angle of the measurement light L incident on the spectral section 3 via the light-passing section 2a based on the peak position of the light intensity of the 0th order light L0. Furthermore, the processing device 10 can obtain the numerical aperture of the measurement light L incident on the spectral section 3 via the light-passing section 2a based on the width of the detection area of ​​the 0th order light L0 in the second photodetector 22.

[0067] The processing device 10 obtains the diffraction efficiency of the spectral unit 3 based on the detection results obtained by the first photodetector 21 and the second photodetector 22, respectively, when light of a predetermined wavelength contained in the -1st-order light L1 is incident on the spectral unit 3 through the light-passing section 2a. For example, when light of a predetermined wavelength contained in the -1st-order light L1 is incident on the light-passing section 2a as an emission line, the light of the predetermined wavelength is reflected by the spectral unit 3, causing the -1st-order light L1 of the predetermined wavelength to be incident on the first photodetector 21 and the 0th-order light L0 of the predetermined wavelength to be incident on the second photodetector 22. Therefore, the processing device 10 can obtain the diffraction efficiency of the spectral unit 3 for light of the predetermined wavelength from the ratio of the light intensity of the -1st-order light L1 of the predetermined wavelength to the light intensity of the 0th-order light L0 of the predetermined wavelength. Here, "the light intensity of the -1st order light L1 at a predetermined wavelength" corresponds to the integrated value of "the light intensity of the -1st order light L1 at a predetermined wavelength" in each first pixel 21a, and "the light intensity of the 0th order light L0 at a predetermined wavelength" corresponds to the integrated value of "the light intensity of the 0th order light L0 at a predetermined wavelength" in each second pixel 22a. [Operation and Effects of Spectroscopic Systems]

[0068] The spectroscopic system 100 comprises the spectrometer 1 described above and a processing unit 10 electrically connected to the first photodetector 21 and the second photodetector 22, respectively. Therefore, the spectroscopic system 100 makes it possible to effectively utilize the detection results of the 0th-order light L0 appropriately acquired by the spectrometer 1.

[0069] In the spectroscopic system 100, the processing unit 10 corrects the relationship between the wavelength and incident position of the -1st order light L1 incident on the first photodetector 21 based on the detection results acquired by the second photodetector 22. This allows for correction of any discrepancies in the relationship between the wavelength and incident position of the -1st order light L1, even if they occur due to deformation (expansion or contraction) of various parts caused by, for example, changes in ambient temperature or heat generation of the photodetector 2.

[0070] In the spectroscopic system 100, the processing unit 10 acquires at least one of the incident angle and numerical aperture of the measurement light L incident on the spectroscopic unit 3 via the light-passing section 2a, based on the detection results acquired by the second photodetector 22. This makes it possible to determine whether the incident angle and numerical aperture of the measurement light L in the light-passing section 2a are appropriate in a plane perpendicular to the Y-axis direction.

[0071] In the spectroscopic system 100, the processing device 10 obtains the diffraction efficiency of the spectroscopic unit 3 based on the detection results obtained by the first photodetector 21 and the second photodetector 22, respectively, when light of a predetermined wavelength contained in the -1st order light L1 is incident on the spectroscopic unit 3 through the light-passing unit 2a. This makes it possible to determine whether the state of the spectroscopic unit 3 is appropriate or not. [Differentiation]

[0072] The present invention is not limited to the examples described above. For example, as shown in Figure 12, the spectrometer 1 may further include a filter 8. The filter 8 is positioned on the optical path of the 0th-order light L0 from the spectroscopic unit 3 to the second photodetector 22 and cuts out light in the same wavelength range as the -1st-order light L1. In the spectrometer 1 shown in Figure 12, the filter 8 is fixed to the surface 20a of the semiconductor substrate 20 so as to cover the second photodetector 22. This makes it possible to acquire the spectrum of the measurement light L in a predetermined wavelength range while detecting the measurement light L outside the predetermined wavelength range. For example, when acquiring the spectrum of fluorescence generated from a measurement target in response to the irradiation of excitation light, the fluorescence is incident on the first photodetector 21 as the -1st-order light L1 and the excitation light is incident on the second photodetector 22 as the 0th-order light L0. In this way, the second photodetector 22 can cut out the fluorescence with the filter 8 and detect the excitation light.

[0073] As shown in Figure 13(a), in the second light detection unit 22, the multiple second pixels 22a may be arranged in a single line along the Y-axis. This allows for determining whether the incident angle and numerical aperture of the measurement light L in the light-transmitting section 2a are appropriate in a plane perpendicular to the X-axis. Alternatively, as shown in Figure 13(b), in the second light detection unit 22, the multiple second pixels 22a may be arranged in a two-dimensional manner. This allows for determining whether the incident angle and numerical aperture of the measurement light L in the light-transmitting section 2a are appropriate in both a plane perpendicular to the X-axis and a plane perpendicular to the Y-axis.

[0074] As shown in Figure 14, the spectrometer 3 may be supported by a light-transmitting member 9 positioned between the photodetector 2 and the spectrometer 3. In the spectrometer 1 shown in Figure 14, the light-transmitting member 9 positioned between the photodetector 2 and the spectrometer 3 has a curved surface 9a formed convexly on the side opposite to the photodetector 2, and the spectrometer 3 is formed on the curved surface 9a. In this case, the optical paths of the measurement light L, the -1st order light L1, and the 0th order light L0 are formed within the light-transmitting member 9 between the photodetector 2 and the spectrometer 3. In the spectrometer 1 shown in Figure 14, the curved surface 9a is formed convexly on the side opposite to the photodetector 2 with a second straight line A2 parallel to the Z-axis as its centerline, and the center C of the light-passing section 2a is offset from the second straight line A2 in the X-axis direction. According to the spectrometer 1 shown in Figure 14, a configuration in which the -1st order light L1 is incident on the first photodetector 21 and the 0th order light L0 is incident on the second photodetector 22 can be easily and reliably realized.

[0075] In the first light detection unit 21, the multiple first pixels 21a may be arranged in a two-dimensional manner. In this case, for each set of multiple first pixels 21a arranged in the Y-axis direction, the signals output from the multiple first pixels 21a arranged in the Y-axis direction may be added together by binning. This addition by binning may be performed in the processing unit 10 or in the circuit section 23 of the light detection element 2.

[0076] In the spectrometer 1, the distance D1 between the light-transmitting section 2a and the first photodetector 21 may be greater than the distance D2 between the light-transmitting section 2a and the second photodetector 22. This allows for the detection of -1st order light L1 on the longer wavelength side.

[0077] In the photodetector 2, the light-passing portion 2a is not limited to a slit formed in the semiconductor substrate 20. The light-passing portion 2a can be configured to allow the passage of measurement light L.

[0078] In the spectrometer 1, the first photodetector 21 only needs to detect diffracted light of a predetermined order that has been spectrally separated by the spectral unit 3 from the measurement light L reflected by the spectral unit 3. For example, the first photodetector 21 may detect the +1st order light that has been spectrally separated by the spectral unit 3 from the measurement light L reflected by the spectral unit 3. Also, in the spectrometer 1, the focusing position P0 of the 0th order light L0 may be located in front of the light-receiving surface of the second photodetector 22 in the direction of propagation of the 0th order light L0. [Explanation of symbols]

[0079] 1...Spectrometer, 2...Photodetector, 2a...Light transmission section, 3...Spectroscopic section, 4...Support member, 4c...Curved surface, 8...Filter, 9...Light transmitting member, 9a...Curved surface, 21...First photodetector, 21a...First pixel, 22...Second photodetector, 22a...Second pixel, 23...Circuit section, 10...Processing device, 100...Spectroscopic system, A1...First line, A2...Second line, C...Center, D1, D2...Distance, F1, F0...Half-width, L...Measured light, L1...-1st order light (diffracted light of a predetermined order), L0...0th order light, P1, P0...Collection position, S1, S0...Amount of displacement, W, W1, W2...Width.

Claims

1. A photodetector having a light-passing portion through which measurement light passes, The system comprises a spectral section that spectrally analyzes and reflects the measurement light that has passed through the light-transmitting section, The aforementioned photodetector element is A first light detection unit includes a plurality of first pixels and detects diffracted light of a predetermined order, which is spectrally separated by the spectroscopic unit from the measurement light reflected by the spectroscopic unit, It includes a second photodetector that contains multiple second pixels and detects the zeroth-order light from the measurement light reflected by the spectral unit, When viewed from the first direction in which the measurement light passes through the light-transmitting section, the light-transmitting section is arranged between the first light-detecting section and the second light-detecting section in a second direction intersecting the first direction. The spectroscopic unit is a spectrometer that spectrally separates and reflects the measurement light such that the full width at half maximum of the zero-order light in the second photodetector is greater than the full width at half maximum of the diffracted light in the first photodetector, with respect to the diffracted light and the zero-order light having the same wavelength.

2. The spectrometer according to claim 1, wherein the spectroscopic unit spectrally analyzes and reflects the measurement light such that the full width at half maximum of the zero-order light in the second photodetector is at least twice the full width at half maximum of the diffracted light in the first photodetector, with respect to the diffracted light and the zero-order light having the same wavelength.

3. The spectrometer according to claim 1, wherein the spectroscopic unit spectrally analyzes and reflects the measurement light such that the amount of shift in the focusing position of the zeroth-order light relative to the second photodetector is greater than the maximum amount of shift in the focusing position of the diffracted light relative to the first photodetector.

4. The spectrometer according to claim 3, wherein the spectroscopic unit spectrally analyzes and reflects the measurement light such that the amount of shift in the focusing position of the zeroth-order light relative to the second photodetector is five times or more the maximum value of the amount of shift in the focusing position of the diffracted light relative to the first photodetector.

5. The spectrometer according to claim 1, wherein, when viewed from the first direction, the light-transmitting section, the first light-detecting section, and the second light-detecting section are each arranged with a first straight line parallel to the second direction as their centerline.

6. The spectrometer according to claim 5, wherein the width of the light-transmitting portion in a third direction intersecting both the first and second directions is greater than the width of the first light-detecting portion in the third direction and greater than the width of the second light-detecting portion in the third direction.

7. The light detection element further includes a circuit section electrically connected to the first light detection unit and the second light detection unit, The spectrometer according to claim 1, wherein, when viewed from the first direction, the light-transmitting section, the first light-detecting section, and the second light-detecting section are offset to one side in a third direction that intersects both the first and second directions, and the circuit section is offset to the other side in the third direction.

8. The spectrometer according to claim 1, wherein the distance between the light-transmitting section and the first light-detecting section is smaller than the distance between the light-transmitting section and the second light-detecting section.

9. The spectrometer according to claim 1, wherein the distance between the light-transmitting section and the first light-detecting section is greater than the distance between the light-transmitting section and the second light-detecting section.

10. The support member further comprises a support member having a curved surface formed in a concave shape on the side opposite to the photodetector, which supports the spectroscopic section at least such that a space is formed between the photodetector and the spectroscopic section, The spectrometer according to claim 1, wherein the spectroscopic section is formed on the curved surface.

11. The curved surface is formed concave on the side opposite to the photodetector, with a second straight line parallel to the first direction as its centerline. The spectrometer according to claim 10, wherein the center of the light-transmitting portion is offset from the second straight line in the second direction.

12. The light-transmitting member further comprises a light-transmitting member that supports at least the spectroscopic unit between the photodetector and the spectroscopic unit, and has a curved surface formed convexly on the side opposite to the photodetector, The spectrometer according to claim 1, wherein the spectroscopic section is formed on the curved surface.

13. The curved surface is formed convexly on the side opposite to the photodetector, with a second straight line parallel to the first direction as its centerline. The spectrometer according to claim 12, wherein the center of the light-transmitting portion is offset from the second straight line in the second direction.

14. The spectrometer according to claim 1, further comprising a filter positioned on the optical path of the zeroth-order light from the spectroscopic unit to the second photodetector, which cuts out light in the same wavelength range as the diffracted light.

15. A spectrometer according to any one of claims 1 to 13, A spectroscopic system comprising a processing unit electrically connected to the first photodetector and the second photodetector, respectively.

16. The spectroscopic system according to claim 15, wherein the processing device corrects the relationship between the wavelength and incident position of the diffracted light incident on the first photodetector based on the detection result obtained by the second photodetector.

17. The spectroscopic system according to claim 15, wherein the processing apparatus acquires at least one of the incident angle and numerical aperture of the measurement light incident on the spectroscopic unit through the light-transmitting unit, based on the detection result acquired by the second photodetector.

18. The spectroscopic system according to claim 15, wherein the processing apparatus obtains the diffraction efficiency of the spectroscopic unit based on the detection results obtained by the first photodetector and the second photodetector, respectively, when light of a predetermined wavelength contained in the diffracted light is incident on the spectroscopic unit through the light-passing unit.

Images