Spectroscope

Abstract

The present invention includes: a housing (2); a light incident member (11); a spectroscopic unit (12); and a detection unit (13) for detecting light dispersed by the spectroscopic unit (12). The light incident member (11) includes a slit (10) that is long in a direction orthogonal to the direction of light dispersion by the spectroscopic unit (12). The spectroscopic unit (12) disperses light, which was incident through the slit (10), in a direction orthogonal to the length direction of the slit. The light incident member (11) is fixed to the housing (2) at a fixing location on one end of the slit (10) in the length-direction thereof, and the other end is movable with respect to the housing (2) in a direction orthogonal to the direction of light dispersion.

Description

spectrometer

[0001] The present invention relates to a spectroscope used to measure the spectral intensity distribution of light to be measured.

[0002] Conventionally, polychromators have been widely used as spectrometers for separating light to be measured into wavelengths and measuring the spectral intensity distribution of each wavelength. These have no moving parts and allow for simultaneous measurement of the entire measurement wavelength range, resulting in high luminous flux utilization efficiency. Polychromators have a slit through which the light to be measured is incident. The polychromator separates the incident light from the slit into wavelength-dependent light components using a spectroscopic section, and the separated light components of each wavelength are received by a detection section such as a light-receiving sensor array.

[0003] The slit is formed in the light entrance member, which is supported by the housing of the spectrometer. The slit is a long, narrow opening, and the width direction of the slit is the direction of light separation by the spectroscopic section.

[0004] When the temperature of the light entrance member increases due to changes in the ambient temperature or the like, the light entrance member expands and contracts in the length direction of the slit. However, conventionally, light entrance members with slits formed therein have been fixed to a housing at both ends of the slit's length. This restricts the light entrance member's expansion and contraction in the slit's length direction. As a result, the light entrance member deforms in the width direction of the slit, causing the slit to shift in the width direction, i.e., shift in the spectral direction caused by the spectroscopic section. This slit shift causes wavelength shifts, which is a problem.

[0005] Patent Document 1 discloses a spectrometer that suppresses positional deviations between the spectroscopic section and the detection section due to temperature changes. Specifically, the spectrometer is composed of two parts: an optical unit on which a slit and a sensor are mounted, and a substrate on which a diffraction grating is mounted. The optical unit and the substrate are in contact at two points, and only one of these points is fixed and cantilevered to suppress positional deviations.

[0006] Patent Document 2 discloses a spectrometer that reduces the influence on the arrangement of optical elements caused by distortion of a container due to temperature changes. Specifically, a member (optical bench) on which the optical elements are mounted and a container that houses this member are connected via a third member (container fixing part). The optical bench and the container fixing part are formed to have a cantilever structure.

[0007] Patent No. 6395389 Publication JP-A-8-145794

[0008] However, the techniques described in Patent Documents 1 and 2 are not techniques related to preventing deformation of the light entrance member in which the slit is formed, and therefore Patent Documents 1 and 2 were unable to provide a solution to the problem that, when the temperature of the light entrance member changes, the slit expands and contracts in the length direction, causing a shift in the width direction (spectral direction) of the slit, resulting in a wavelength shift.

[0009] An object of the present invention is to provide a spectroscope that can prevent wavelength shift even if the light incident member expands or contracts in the length direction of the slit.

[0010] The above object is achieved by the following means: (1) A spectrometer comprising a housing, a light entrance member, a spectroscopic unit, and a detection unit that detects light separated by the spectroscopic unit, wherein the light entrance member has a slit that is long in a direction perpendicular to the direction of spectroscopic separation by the spectroscopic unit, and the spectroscopic unit separates the light incident through the slit in a direction perpendicular to the length of the slit, and the light entrance member is fixed to the housing at a fixed position on one end side of the length of the slit and is movable at the other end side relative to the housing in the direction perpendicular to the spectroscopic direction. (2) The spectrometer according to the preceding paragraph 1, wherein the light entrance member is supported by the housing at a movable support position that is spaced apart in the length of the slit from the fixed position on the one end side, such that movement of the light entrance member in the spectroscopic direction by the spectroscopic unit is restricted but movement in the direction perpendicular to the spectroscopic direction is not restricted. (3) The spectrometer according to the preceding paragraph 2, wherein the light entrance member is supported at the movable support position by fitting a protrusion fixed to the housing into a longitudinal intermediate portion of a fitting opening that is formed in the light entrance member and is long in the length direction of the slit. (4) The spectrometer according to the preceding paragraph 2 or 3, wherein the fixed position and the movable support position of the light entrance member are equidistant from the center of the slit. (5) The spectrometer according to the preceding paragraph 2 or 3, wherein the fixed position and the movable support position are on a line passing through the center of the slit. (6) The spectrometer according to any one of the preceding paragraphs 1 to 3, wherein the shape of the light entrance member is symmetrical in the length direction of the slit with respect to the center of the slit. (7) The spectrometer according to any one of the preceding paragraphs 1 to 3, further comprising a restricting member that restricts movement of the light entrance member in a direction away from the housing. (8) The spectrometer according to the preceding paragraph 7, wherein the restricting member is a biasing member that biases the light entrance member toward the housing. (9) A spectrometer comprising a housing, a light entrance member, a spectroscopic section, and a detection section for detecting light separated by the spectroscopic section, wherein the light entrance member has a long slit in a direction perpendicular to the direction of separation by the spectroscopic section, and the spectroscopic section separates the light incident through the slit in a direction perpendicular to the length of the slit, and the light entrance member is supported by the housing at at least two movable support positions spaced apart in the length direction of the slit, in a state in which the entire light entrance member can move relative to the housing in a direction perpendicular to the direction of separation.(10) The spectrometer according to the preceding paragraph 9, wherein the light entrance member is supported by the housing in a state in which movement in the spectroscopic direction by the spectroscopic unit is restricted at each of the movable support positions, but movement in a direction perpendicular to the spectroscopic direction is not restricted. (11) The spectrometer according to the preceding paragraph 10, wherein the light entrance member is supported at the movable support positions by fitting a protrusion fixed to the housing into a longitudinal intermediate portion of a fitting opening formed in the light entrance member and extending in the longitudinal direction of the slit. (12) The spectrometer according to any of the preceding paragraphs 9 to 11, wherein there are two movable support positions, each equidistant from the center of the slit. (13) The spectrometer according to any of the preceding paragraphs 9 to 11, wherein each movable support position is on a line passing through the center of the slit. (14) The spectrometer according to any of the preceding paragraphs 9 to 11, wherein the shape of the light entrance member is symmetrical in the longitudinal direction of the slit with respect to the center of the slit. (15) The spectrometer according to any one of the preceding paragraphs 9 to 11, further comprising a restricting member that restricts movement of the light incident member in a direction away from the housing. (16) The spectrometer according to the preceding paragraph 15, wherein the restricting member is a biasing member that biases the light incident member toward the housing.

[0011] In the spectrometer according to the present invention, the light entrance member is fixed to the housing at one end in the length direction of the slit and the other end is movable in a direction perpendicular to the direction of spectroscopic separation by the spectroscopic section. Alternatively, the light entrance member is supported by the housing at at least two movable support positions spaced apart in the length direction of the slit so that the entire light entrance member is movable relative to the housing in a direction perpendicular to the direction of spectroscopic separation by the spectroscopic section.

[0012] Therefore, when the light entrance member expands or contracts in the length direction of the slit due to changes in the environmental temperature or the like, the light entrance member can move in a direction perpendicular to the spectral direction without being hindered from expanding or contracting at the other end of the length direction of the movable slit. Alternatively, the entire light entrance member can move in a direction perpendicular to the spectral direction without being hindered from expanding or contracting. In other words, unlike conventional devices, because the light entrance member is fixed at both ends of the length direction of the slit, the light entrance member does not deform in the width direction of the slit (spectral direction). As a result, the slit is prevented from shifting in the width direction, and wavelength shifts are prevented.

[0013] 7 is a schematic configuration diagram of a spectrometer according to an embodiment of the present invention; FIG. 10 is a top view of the spectrometer as viewed from the light incident member side; FIG. 11 is an enlarged view of the light incident member and its peripheral portion shown in FIG. 2; (A) is a cross-sectional view taken along line 4A-4A in FIG. 3, and (B) is a cross-sectional view taken along line 4B-4B in FIG. 3; FIG. 12 is a view showing a modified light incident member; FIG. 13 is a view showing a modified light incident member; FIG. 14 is a view showing a modified light incident member; FIG. 15 is a view showing a modified light incident member; FIG. 16 is a view showing a modified light incident member; FIG. 17 is a view showing a modified light incident member; FIG. 18 is a view showing a modified light incident member;

[0014] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0015] 1 is a schematic diagram of a spectrometer 1 according to one embodiment of the present invention. This spectrometer 1 includes a light incident member 11, a spectroscopic unit 12 consisting of a diffraction grating, and a detection unit 13 consisting of a light receiving sensor array or the like. The spectroscopic unit 12 and the detection unit 13 are housed in a housing 2. The light incident member 11 is supported on the outer surface of the housing 2. How the light incident member 11 is supported by the housing 2 will be described later.

[0016] A slit 10 is formed in the light incident member 11, through which the light to be measured L from the measurement object is incident. The spectroscopic unit 12 reflects and disperses the light to be measured L that has passed through the slit 10 into a dispersed image according to the wavelength, and forms an image on the light receiving sensor array of the detection unit 13.

[0017] The detector 13 comprises a plurality of photoelectric conversion sensors arranged at predetermined intervals. An electrical signal corresponding to the intensity of received light output from each sensor is processed by a processor (not shown).

[0018] 2 is a top view of the spectrometer 1, as viewed from the light entrance member 11 side. The light entrance member 11 is attached to the right end of the housing 2, and a detection unit 13 is built into the left end of the housing. Although not shown, the spectroscopic unit 12 is housed in the housing 2 at a position below the light entrance member 11.

[0019] Fig. 3 is an enlarged view of the light incident member 11 and its surrounding area shown in Fig. 2. Fig. 4(A) is a cross-sectional view taken along line 4A-4A in Fig. 3, and Fig. 4(B) is a cross-sectional view taken along line 4B-4B in Fig. 3.

[0020] The light incidence member 11 is made of a metal plate with a thickness of approximately 0.03 mm and is rectangular with long and short sides. The slit 10 is a long, narrow opening. The slit 10 is formed in approximately the center of the light incidence member 11. The length direction of the slit 10 is parallel to the long sides of the light incidence member 11.

[0021] If the thickness of the light entrance member 11 (thickness of the slit 10) is large, light may be reflected by the inner wall of the slit 10, and this light may become stray light and adversely affect the measurement. For this reason, the upper limit of the thickness of the slit 10 should be about 0.1 mm, and it is preferable that it be 0.03 to 0.1 mm.

[0022] The line passing through the center of the slit 10 and extending in the length direction of the slit 10 is defined as the X-axis. The line passing through the center of the slit 10 and extending in a direction perpendicular to the X-axis, in other words, in the width direction of the slit 10, is defined as the Y-axis. The Y-axis direction is the direction of wavelength dispersion by the spectroscopic section 12. The X-axis direction is the direction perpendicular to the spectroscopic direction.

[0023] A circular fitting hole 110 is formed in the light entrance member 11 at a position on the X-axis at one end in the length direction of the slit 10. In addition, a U-shaped groove 111 (corresponding to a fitting opening) cut out from the edge of the light entrance member 11 toward the slit 10 is formed in the light entrance member 11 at a position on the X-axis at the other end in the length direction of the slit 10.

[0024] Cylindrical protrusions 21 and 22 are formed on the housing 2 at positions corresponding to the fitting hole 110 and U-shaped groove 111 of the light incident member 11. The outer diameter of the protrusion 21 corresponding to the fitting hole 110 is approximately the same as the diameter of the fitting hole 110. The outer diameter of the protrusion 22 corresponding to the U-shaped groove 111 is set to be approximately the same as or slightly smaller than the width of the U-shaped groove 111.

[0025] 3 and 4A, the fitting hole 110 of the light incident member 11 is fitted onto the protrusion 21 of the housing 2 and fixed thereto. If necessary, the light incident member 11 and the protrusion 21 are bonded or crimped together while the fitting hole 110 and the protrusion 21 are fitted together. This restricts movement of the light incident member 11 in the X-axis direction, Y-axis direction, and Z-axis direction (light incident direction) that is perpendicular to the X-axis direction and Y-axis direction at the fitting portion of the fitting hole 110 and the protrusion 21.

[0026] The light incident member 11 and the housing 2 can be joined by fitting the projection 21 into the fitting hole 110, or the projection 22 can be formed as a screw and screwed into the housing 2 to fix it.

[0027] 3 and 4B, the U-shaped groove 111 of the light incident member 11 is also fitted into the protrusion 22 of the housing 2. In the fitted state, the protrusion 22 is located midway along the length of the U-shaped groove 111. Therefore, a gap 112 is formed between the bottom of the U-shaped groove 111 and the protrusion 22, and a gap 113 also exists on the opposite side of the protrusion 22 from the bottom of the U-shaped groove 111. These gaps 112 and 113 serve to allow for expansion and contraction deformation of the light incident member 11 due to changes in the environmental temperature, etc.

[0028] That is, when the temperature of the light incidence member 11 rises, linear expansion of the light incidence member 11 occurs, causing the light incidence member 11 to expand in the X-axis direction. When the temperature of the light incidence member 11 drops, the light incidence member 11 contracts in the X-axis direction. Because gaps 112 and 113 are formed on both sides of the protrusion 22 in the X-axis direction, even if the light incidence member 11 expands or contracts in the X-axis direction, interference between the light incidence member 11 and the protrusion 22 does not occur, preventing the expansion and contraction deformation of the light incidence member 11. In other words, the light incidence member 11 can freely deform in the X-axis direction. Therefore, deformation in the X-axis direction is prevented, preventing the slit 10 from shifting in the Y-axis direction due to forced deformation of the light incidence member in the Y-axis direction (spectral direction). As a result, shifts in the imaging position in the Y-axis direction caused by shifts in the slit 10 in the Y-axis direction do not occur, and wavelength shifts can be prevented.

[0029] Furthermore, when both ends of the slit 10 in the light entrance member 11 are fixed, particularly when the temperature of the light entrance member 11 rises, there is a risk that the slit 10 will not only shift in the Y-axis direction but also warp or bulge in the Z-axis direction. In contrast, in this embodiment, the light entrance member 11 is free to deform in the X-axis direction, so bending in the Z-axis direction, in other words, deformation of the light entrance member 11 in the focusing direction, can be prevented. This prevents out-of-focus images and changes in the spectral performance (half-width).

[0030] In this embodiment, the fitting position (corresponding to the fixed position) between the fitting hole 110 and the protrusion 21 and the fitting position (corresponding to the movable support position) between the U-shaped groove 111 and the protrusion 22 are equidistant from the center of the slit 10 and are formed at symmetrical positions about the Y axis. This makes it possible to further prevent changes in the spectral performance (half width) of the light entrance member 11.

[0031] Furthermore, the fitting position between the fitting hole 110 and the protrusion 21 and the fitting position between the U-shaped groove 111 and the protrusion 22 are both on the X-axis line, which further prevents deformation of the light incident member 11 in the Y-axis direction.

[0032] In this embodiment, the shape of the light incident member 11 is substantially symmetrical about the Y axis. Therefore, when the light incident member 11 expands or contracts in the X axis direction due to temperature changes, frictional forces act evenly between the light incident member 11 and the housing 2, preventing the light incident member 11 from tilting in the Z axis direction.

[0033] 5 and 6 are diagrams showing modified examples of the light entrance member 11. FIG.

[0034] In the embodiment shown in Figures 3 and 4, a U-shaped groove 111 is formed on the other end of the length of the slit 10 in the light incident member 11, and the light incident member 11 is supported on the housing 2 in a state where it can move in the X-axis direction via the protrusion 22.

[0035] However, instead of the U-shaped groove 111, a rectangular elongated hole 111 (corresponding to the fitting opening) as shown in Fig. 5 may be used. In this case, too, the elongated hole 111 and the protrusion 22 are fitted together so that the protrusion 22 on the housing 2 is positioned at the middle position in the longitudinal direction of the elongated hole 111. This allows the light incident member 11 to move in the X-axis direction.

[0036] 6, the elongated hole 111 may be disposed between the slit 10 and the round hole 110 used for fixing to the housing 2. In this case, the elongated hole 111 and the protrusion 22 are fitted together so that the protrusion 22 on the housing 2 side is positioned at the middle position in the longitudinal direction of the elongated hole 111. This allows the light incident member 11 to move in the X-axis direction.

[0037] Furthermore, the elongated hole 111 does not have to be rectangular. For example, the elongated hole 111 may be oval or elliptical, with both ends in the lengthwise direction curved in an arc shape.

[0038] In both the cases of FIG. 5 and FIG. 6, it is desirable that the fixed position by the round hole 110 and the protrusion 21 and the movably supported position by the long hole 111 and the protrusion 22 are located on the X-axis.

[0039] Furthermore, the movable support position supported by the housing 2 in a state that allows movement of the light incident member 11 in the X-axis direction and restricts movement in the Y-axis direction is not limited to one, but may be multiple positions on the X-axis line or off the X-axis line.

[0040] In the above embodiment, an example is shown in which the light incident member 11 is fixed to the housing 2 at one end side of the light incident member 11, while the protrusion 22 is fitted into the U-shaped groove or the long hole 111 at a movable support position that is spaced apart in the longitudinal direction of the slit 10 from the fixed position at the one end side.

[0041] However, the spectrometer 1 may have one end of the light entrance member 11 fixed to the housing 2, but no U-shaped groove or elongated hole 111, and no protrusion 22 on the housing 2 side. In this case, too, the other end in the longitudinal direction of the slit 10 of the light entrance member 11 moves in response to expansion and contraction of the light entrance member 11 caused by temperature changes. In other words, because the expansion and contraction of the light entrance member 11 in the X-axis direction is not impeded, deformation of the light entrance member 11 in the Y and Z directions is prevented, and wavelength shifts are prevented.

[0042] However, when a U-shaped groove or an elongated hole 111 is formed in the light incidence member 11 and the protrusion 22 on the housing 2 side is fitted into the U-shaped groove or the elongated hole 111, the movement of the light incidence member 11 in the Y-axis direction is restricted by the protrusion 22. In other words, the U-shaped groove or the elongated hole 111 and the protrusion 22 play a role in positioning the light incidence member 11 in the Y-axis direction. For this reason, as in the above-described embodiment, it is desirable that the light incidence member 11 be supported by the housing 2 in a state in which the U-shaped groove or the elongated hole 111 is fitted into the protrusion 22 on the housing 2 side.

[0043] Next, another embodiment of the present invention will be described with reference to FIGS.

[0044] In this embodiment, the light incident member 11 is prevented from deforming in the direction (Z-axis direction) away from the housing 2. If the light incident member 11 deforms in the Z-axis direction and moves away from the housing 2, the focusing state changes and the spectral performance (half-width) deteriorates. For this reason, a regulating member 14 is placed over the light incident member 11 from the opposite side of the housing 2, sandwiching the light incident member 11 therebetween, and the regulating member 14 prevents the light incident member 11 from deforming in the direction away from the housing 2.

[0045] Specifically, as shown in Figures 7 and 8, the restricting member 14 is fitted and fixed to the protrusion 22 of the housing 2. In Figure 7, the restricting member 14 is shown by double hatching. As shown in Figure 8, the protrusion 22 has a stepped shape with a large-diameter protrusion 22a and a small-diameter protrusion 22b formed at the tip thereof. A step 22c consisting of the annular surface of the large-diameter protrusion 22a is formed at the boundary between the large-diameter protrusion 22a and the small-diameter protrusion 22b.

[0046] The regulating member 14 is fixed to the small diameter protrusion 22b by using adhesive, crimping, or other methods as necessary, with the fitting hole formed in the regulating member 14 fitted into the small diameter protrusion 22b until it contacts the step portion 22c.

[0047] The height of the large-diameter convex portion 22a is set slightly larger than the thickness of the light incident member 11. Therefore, when the U-shaped groove or elongated hole 111 of the light incident member 11 is fitted up to the base end of the large-diameter convex portion 22a, a gap 16 is formed between the light incident member 11 and the restricting member 14, as shown in FIG. 8 . The presence of this gap 16 prevents contact between the light incident member 11 and the restricting member 14 when the light incident member 11 expands or contracts in the X-axis direction, preventing the frictional force caused by contact from impeding the expansion and contraction deformation. On the other hand, if the light incident member 11 deforms in a direction away from the housing 2 beyond the size of the gap 16, the light incident member 11 comes into contact with the restricting member 14. Therefore, further deformation in the separating direction is prevented.

[0048] In FIG. 8, reference numeral 23 denotes an opening provided in the housing 2 for guiding the light that has passed through the slit 10 into the inside of the spectroscope 1 .

[0049] 7 and 8 , the size of the regulating member 14 is set to be approximately the same as the size of the region on the other end side of the light incident member 11. However, the size and fixing method of the regulating member 14 are not limited. For example, the regulating member 14 may be fixed in a strip shape to the housing 2 on both sides of the light incident member 11 in the Y-axis direction, so that the regulating member 14 covers the light incident member 11.

[0050] 9 shows a modified example of the restricting member. In this example, a coil spring 15, an example of a biasing member, is used as the restricting member. The coil spring 15 is inserted through the body portion 22d of the protrusion 22 between the large-diameter head portion 22e of the protrusion 22 and the light incident member 11. The coil spring 15 applies a compressive force to the light incident member 11 toward the housing 2. This compressive force prevents deformation of the light incident member 11 in a direction away from the housing 2. However, the compressive force of the coil spring 15 is set to a strength that allows the light incident member 11 to expand and contract in the X-axis direction.

[0051] FIG. 10 is a diagram showing still another embodiment of the present invention, and is a top view of the spectrometer 1, similar to FIG.

[0052] In the embodiment shown in FIGS. 2 to 9, the light incidence member 11 is fixed to the housing 2 at a fixed position on one end side of the slit 10 in the length direction of the light incidence member 11 .

[0053] In contrast, in the embodiment shown in Figure 10, the light incident member 11 is not fixed to the housing 2, and both ends of the length of the slit 10 of the light incident member 11 are supported by the housing 2 in a state where they can move in the X-axis direction.

[0054] Specifically, U-shaped grooves 111 and 114 are formed at both ends in the length direction of the slit 10 of the light entrance member 11. Each of the U-shaped grooves 111 and 114 is cut out from both end edges of the light entrance member 11 in the X-axis direction toward the slit 10.

[0055] The housing 2 has cylindrical protrusions 22, 24 formed at positions corresponding to the U-shaped grooves 111, 114 of the light incident member 11. The outer diameter of each of the protrusions 22, 24 is set to be approximately the same as or slightly smaller than the width of the U-shaped grooves 111, 114.

[0056] The two U-shaped grooves 111, 114 of the light incident member 11 are fitted into the two protrusions 22, 24 of the housing 2, respectively. In the fitted state, each protrusion 22, 24 is located midway in the longitudinal direction of each U-shaped groove 111, 114. Therefore, a gap 112 is formed between the bottom of each U-shaped groove 111, 114 and each protrusion 22, and a gap 113 also exists on the opposite side of the protrusion 22 from the bottom of the U-shaped grooves 111, 114. These gaps 112, 113 serve to allow expansion and contraction deformation of the light incident member 11 due to changes in environmental temperature, etc.

[0057] That is, when the temperature of the light incidence member 11 rises, linear expansion of the light incidence member 11 occurs, causing the light incidence member 11 to expand in the X-axis direction. When the temperature of the light incidence member 11 drops, the light incidence member 11 contracts in the X-axis direction. Because gaps 112 and 113 are formed on both sides of the protrusions 22 and 24 in the X-axis direction, even if the light incidence member 11 expands or contracts in the X-axis direction, interference between the light incidence member 11 and the protrusions 22 does not occur, preventing the expansion and contraction deformation of the light incidence member 11. In other words, the light incidence member 11 can freely deform in the X-axis direction. Therefore, deformation of the light incidence member 11 in the X-axis direction is prevented, preventing the light incidence member 11 from being forcibly deformed in the Y-axis direction (spectral direction), and preventing the slit 10 from shifting in the Y-axis direction. As a result, shifting of the imaging position in the Y-axis direction due to shifting of the slit 10 in the Y-axis direction does not occur, and wavelength shift can be prevented.

[0058] Furthermore, if both ends of the slit 10 in the light entrance member 11 are fixed, particularly if the temperature of the light entrance member 11 rises, there is a risk that the slit 10 will not only shift in the Y-axis direction but also warp or bulge in the Z-axis direction. In contrast, in this embodiment, the light entrance member 11 is free to deform in the X-axis direction, so bending in the Z-axis direction, in other words, deformation in the focusing direction, can be prevented. This prevents out-of-focus images and changes in the spectral performance (half-width).

[0059] In this embodiment, the engagement positions (corresponding to movable support positions) between the U-shaped grooves 111, 114 and the protrusions 22, 24 are equidistant from the center of the slit 10 and are formed at symmetrical positions about the Y axis. This makes it possible to further prevent changes in the spectral performance (half-width) of the light entrance member 11.

[0060] Furthermore, the fitting positions of the U-shaped grooves 111, 114 and the projections 22, 24 are all on the X-axis, which further prevents deformation of the light incident member 11 in the Y-axis direction.

[0061] Furthermore, the movement of the light incident member 11 in the Y-axis direction is restricted by the presence of the protrusions 22 and 24. In other words, the U-shaped groove 111 and the protrusions 22 play a role in positioning the light incident member 11 in the Y-axis direction.

[0062] 10, the U-shaped grooves 111, 114 may be replaced with rectangular elongated holes 111, 114 as shown in Fig. 11. In this case, too, the elongated holes 111, 114 are fitted with the protrusions 22, 24 on the housing 2 so that they are positioned at the middle positions in the longitudinal direction of the elongated holes 111, 114. This allows the light incident member 11 to move in the X-axis direction.

[0063] 12, one of the elongated holes 111 may be disposed between the other elongated hole 114 and the slit 10. In this case, too, the elongated holes 111, 114 are fitted into the protrusions 22, 24 on the housing 2 so that the protrusions 22, 24 are positioned at the middle positions in the longitudinal direction of the elongated holes 111, 114. This allows the light incident member 11 to move in the X-axis direction.

[0064] Furthermore, the elongated holes 111 and 114 do not have to be rectangular. For example, the elongated holes 111 and 114 may be oval or elliptical with both ends in the lengthwise direction curved in an arc shape.

[0065] In both the cases of FIG. 11 and FIG. 12, it is desirable that the movable support positions by the elongated holes 111, 114 and the protrusions 22, 24 are located on the X-axis.

[0066] 10 to 12, similarly to the embodiment of FIGS. 7 and 8, in order to restrict movement of the light entrance member 11 in the Z-axis direction, a restricting member may be provided covering the light entrance member 11 on the side opposite the housing 2. FIG. 13 shows a case in which restricting members 14, 17 are provided at both ends of the slit 10 of the light entrance member 11 in the length direction. In FIG. 13, the restricting members 14, 17 are double-hatched.

[0067] 7 and 8, in the embodiment of Fig. 13, the restricting members 14 and 16 are attached using the protrusions 22 and 24 so that a small gap is formed between the restricting members 14 and 16 and the light incident member 11. Note that only one of the restricting members 14 and 17 may be used. Alternatively, strip-shaped restricting members may be fixed to the housing on both sides of the light incident member 11 in the Y-axis direction, so that the restricting members cover the light incident member 11.

[0068] 9, a biasing member such as a coil spring may be attached to one or both of the protrusions 22, 24 as a restricting member.

[0069] This application claims priority to Japanese Patent Application No. 2023-196000, filed on November 17, 2023, the disclosure of which is incorporated herein by reference in its entirety.

[0070] The present invention can be used as a spectroscope used to measure the spectral intensity distribution of light to be measured.

[0071] REFERENCE SIGNS LIST 1 spectroscope 2 housing 10 slit 11 light incident member 12 spectroscopic section 13 detection section 14, 17 regulating member 15 coil spring (biasing member) 16 gap 21 protrusion 22 protrusion 22a large diameter convex section 22b small diameter convex section 22c step section 22d body section 22e large diameter head section 110 round hole 111, 114 U-shaped groove or elongated hole 112, 113 gap

Claims

1. A spectrometer comprising a housing, a light entrance member, a spectroscopic section, and a detection section for detecting light separated by the spectroscopic section, wherein the light entrance member has a long slit in a direction perpendicular to the direction of separation by the spectroscopic section, and the spectroscopic section separates the light entering through the slit in a direction perpendicular to the length of the slit, and the light entrance member is fixed to the housing at a fixed position on one end side of the length of the slit, and the other end side is movable relative to the housing in the direction perpendicular to the spectroscopic direction.

2. A spectrometer as described in claim 1, wherein the light input member is supported by the housing at a movable support position spaced apart in the longitudinal direction of the slit from a fixed position on one end side, in a state in which movement in the spectroscopic direction by the spectroscopic section is restricted, but movement in a direction perpendicular to the spectroscopic direction is not restricted.

3. A spectrometer as described in claim 2, wherein the light input member is supported at the movable support position by fitting a protrusion fixed to the housing into the middle part of the longitudinal direction of an engagement opening formed in the light input member and which is long in the longitudinal direction of the slit.

4. A spectrometer according to claim 2 or 3, wherein the fixed position and the movable support position of the light incidence member are equidistant from the center of the slit.

5. A spectrometer as claimed in claim 2 or 3, wherein the fixed position and the movable support position are on a line passing through the centre of the slit.

6. A spectrometer according to any one of claims 1 to 3, wherein the shape of the light entrance member is symmetrical in the longitudinal direction of the slit with respect to the center of the slit.

7. A spectrometer according to any one of claims 1 to 3, further comprising a restricting member for restricting movement of said light incidence member in a direction away from said housing.

8. The spectrometer according to claim 7, wherein the regulating member is a biasing member that biases the light incident member toward the housing.

9. A spectrometer comprising a housing, a light entrance member, a spectroscopic section, and a detection section for detecting light separated by the spectroscopic section, wherein the light entrance member has a long slit in a direction perpendicular to the direction of separation by the spectroscopic section, and the spectroscopic section separates the light entering through the slit in a direction perpendicular to the length of the slit, and the light entrance member is supported by the housing in a state in which the entire light entrance member can move in the direction perpendicular to the spectroscopic direction relative to the housing at at least two movable support positions spaced apart in the length direction of the slit.

10. A spectrometer as described in claim 9, wherein the light input member is supported by the housing in a state in which movement in the spectroscopic direction by the spectroscopic section is restricted at each of the movable support positions, but movement in a direction perpendicular to the spectroscopic direction is not restricted.

11. A spectrometer as described in claim 10, wherein the light incident member is supported at the movable support position by fitting a protrusion fixed to the housing into the middle part of a fitting opening formed in the light incident member and extending in the longitudinal direction of the slit.

12. A spectrometer as claimed in any one of claims 9 to 11, wherein there are two said movable support positions, each of which is equidistant from the centre of the slit.

13. A spectrometer according to any one of claims 9 to 11, wherein each movable support position is on a line passing through the center of said slit.

14. A spectrometer according to any one of claims 9 to 11, wherein the shape of the light entrance member is symmetrical in the longitudinal direction of the slit with respect to the center of the slit.

15. A spectrometer according to any one of claims 9 to 11, further comprising a restricting member for restricting movement of the light incidence member in a direction away from the housing.

16. The spectrometer according to claim 15, wherein the regulating member is a biasing member that biases the light incident member toward the housing.

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