JP2016142523A - Spectral characteristic measuring apparatus and adjustment method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a spectral characteristic measuring apparatus capable of acquiring a clear interferogram.SOLUTION: A spectral characteristic measuring apparatus comprises: a fixed reflection surface 201 and a movable reflection surface 301 arranged side by side; an objective lens 10 for guiding a measurement beam emitted from a measurement point of a measurement target object to the fixed reflection surface 201 and the movable reflection surface 301; an imaging lens 12 for condensing measurement beams reflected on the fixed reflection surface 201 and the movable reflection surface 301 onto an imaging surface respectively; a CCD camera 13 having a plurality of detection pixels two-dimensionally arranged on the imaging surface; and a processing unit 141 finding an interferogram of the measurement beam on the basis of light intensity change detected by the CCD camera 13 by moving the movable reflection surface 301, and acquiring a spectrum through Fourier transformation of the interferogram. The apparatus further comprises a determination unit 142 which determines whether or not the movable reflection surface 301 is relatively inclined with respect to the fixed reflection surface 201 on the basis of the detection result of the CCD camera 13.SELECTED DRAWING: Figure 5

Description

  The present invention relates to a spectral characteristic measuring apparatus for measuring spectral characteristics of measurement light such as transmitted light, reflected light, and fluorescence emitted from an object to be measured, and an adjustment method thereof.

  One technique for measuring spectral characteristics is a technique called imaging type two-dimensional Fourier spectroscopy (see Patent Document 1). In this method, as shown in FIG. 1, omnidirectional light (measurement light) emitted from a sample surface (object surface) is converted into a parallel light beam by an objective lens, and then a phase shifter composed of a fixed mirror portion and a movable mirror portion. , And the measurement light (reflected light) reflected by both mirrors is condensed at the same point on the imaging plane by the imaging lens. By moving the movable mirror part and providing a difference in optical path length between the measurement light reflected by the fixed mirror part and the measurement light reflected by the movable mirror part, the measurement light collected on the imaging surface interferes. Then, interference light of the measurement light is formed. By detecting the intensity of the interference light at each pixel of a two-dimensional array device such as a CCD camera disposed on the imaging plane, an interferogram that is a change in the interference light intensity is obtained. The spectral characteristic (spectrum) of the measurement light is obtained by mathematically Fourier transforming.

JP 2008-309706 A

  In order to obtain accurate and reproducible spectral characteristics, it is necessary to ensure that the measurement light reflected by the fixed mirror and the measurement light reflected by the movable mirror intersect each other on the image plane by the imaging lens. is there. Therefore, the relative positional relationship between the fixed mirror part and the movable mirror part is adjusted so that the directions of the reflecting surfaces of both mirror parts are aligned. Such adjustment of the fixed mirror portion and the movable mirror portion is usually performed at the time of manufacturing the apparatus.

  However, there is a case in which the direction of the reflection surface of the movable mirror portion and the direction of the reflection surface of the fixed mirror portion may be displaced due to repeated movement of the movable mirror portion or due to external factors such as vibration. Such a deviation in the orientation of the two reflecting surfaces is due to the converging position between the reflected light from the fixed mirror portion and the reflected light from the movable mirror portion, which should be condensed at the same position on the imaging surface by the imaging lens. Cause a shift. Therefore, the direction of the reflective surface changes when the movable mirror is moved by moving the movable mirror with high precision by means of a piezoelectric element or an electrostatic drive actuator using MEMS (Micro Electro Mechanical Systems) technology. In order to suppress this as much as possible, there is a case where the converging position is largely deviated so that interference light is not formed even if the deviation in the direction of the reflecting surfaces of the fixed mirror portion and the movable mirror portion cannot be visually recognized.

Specifically, as shown in FIG. 2, the angle deviation between the fixed reflecting surface and the movable reflecting surface is φ [deg.], The focal length of the imaging lens is f [mm], and the light is condensed on the imaging surface. If the positional deviation amount is d [mm], the relationship between d, φ, and f is expressed by the following equation (1).
d = 2 × f × tanφ (1)
As can be seen from the equation (1), even if the angle shift amount φ is small, the condensing position shift amount d increases depending on the focal length f of the imaging lens.
Thus, if the condensing position of the reflected light of a fixed mirror part and the reflected light of a movable mirror part shift | deviates large, both reflected light will not interfere on an imaging surface and an interferogram cannot be acquired.

  A problem to be solved by the present invention is a spectral characteristic measuring apparatus and a spectral characteristic measurement capable of recognizing a slight deviation in inclination between a fixed reflecting surface and a movable reflecting surface and obtaining accurate and reproducible spectral characteristics. An apparatus adjustment method is provided.

The spectral characteristic measuring apparatus according to the present invention, which has been made to solve the above problems,
a) a fixed reflecting surface and a movable reflecting surface arranged side by side;
b) an introduction optical system that guides measurement light emitted from the measurement point of the object to be measured to the fixed reflection surface and the movable reflection surface;
c) Image formation for condensing the measurement light introduced into the fixed reflection surface and reflected by the fixed reflection surface and the measurement light introduced into the movable reflection surface and reflected by the movable reflection surface on the image formation surface, respectively. Optical system,
d) a light detection unit for detecting the intensity of the light collected on the imaging surface, having a plurality of detection pixels arranged two-dimensionally on the imaging surface;
e) Processing for obtaining an interferogram of the measurement light based on a change in light intensity detected by the light detection unit by moving the movable reflecting surface, and acquiring a spectrum by Fourier transforming the interferogram In a spectral characteristic measuring device comprising a unit,
And determining means for determining whether or not the movable reflecting surface is inclined relative to the fixed reflecting surface based on a detection result of the light detection unit.

In the spectral characteristic measuring apparatus,
Furthermore, a first jig for adjusting the amount of inclination of the movable reflecting surface around a first axis parallel to the movable reflecting surface, and a second axis perpendicular to the first axis and parallel to the fixed reflecting surface It is preferable to include a second jig for adjusting the amount of inclination of the surrounding fixed reflecting surface.
According to such a configuration, when the determination unit determines that the movable reflection surface is relatively inclined with respect to the fixed reflection surface, the first jig, the second jig, or the first and second jigs The inclination of the movable reflecting surface and / or the fixed reflecting surface can be easily adjusted using both of the second jigs.

In addition, the method for adjusting the spectral characteristic measuring apparatus according to the present invention includes:
a) a fixed reflecting surface and a movable reflecting surface arranged side by side;
b) an introduction optical system that guides measurement light emitted from the measurement point of the object to be measured to the fixed reflection surface and the movable reflection surface;
c) Image formation for condensing the measurement light introduced into the fixed reflection surface and reflected by the fixed reflection surface and the measurement light introduced into the movable reflection surface and reflected by the movable reflection surface on the image formation surface, respectively. Optical system,
d) a light detection unit for detecting the intensity of the light collected on the imaging surface, having a plurality of detection pixels arranged two-dimensionally on the imaging surface;
e) Processing for obtaining an interferogram of the measurement light based on a change in light intensity detected by the light detection unit by moving the movable reflecting surface, and acquiring a spectrum by Fourier transforming the interferogram In a spectral characteristic measuring device comprising a unit,
The relative inclination of the movable reflective surface with respect to the fixed reflective surface is adjusted based on the detection result of the light detection unit.

  A group of rays emitted from an ideal luminescent spot on the object plane causes Fraunhofer diffraction due to the circular aperture of the lens constituting the splitting optical system and the imaging optical system, and is a concentric light and dark pattern called an Airy pattern. Interference fringes are formed on the image plane. The Airy pattern (light / dark pattern) is a bright region whose center is called an “Airy disk”, and a plurality of concentric rings surround it. In general, an Airy disk is understood as a multi-beam interference phenomenon due to a circular aperture of a lens.

  Therefore, an Airy pattern is also formed on the image plane by Fraunhofer diffraction for the measurement light reflected by the fixed reflection surface and the measurement light reflected by the movable reflection surface. When the fixed reflection surface and the movable reflection surface have the same inclination, the measurement light reflected by the fixed reflection surface and the measurement light reflected by the movable reflection surface are collected at the same point on the imaging surface. The airy pattern corresponding to the light is observed in a state of being overlapped (see FIG. 3).

On the other hand, when a relative angular deviation φ occurs between the fixed reflecting surface and the movable reflecting surface, the measurement light reflected by the fixed reflecting surface and the movable reflecting surface on the imaging surface is imaged geometrically. Cannot cross one point on the surface. For this reason, as shown in FIG. 4, the Airy pattern by the measurement light from the fixed reflecting surface and the movable reflecting surface is observed on the imaging surface in a shifted state.
Therefore, it can be determined that the movable reflective surface is inclined relative to the fixed reflective surface from the state of the Airy pattern observed on the imaging surface.

  By the way, the limits of the separation of two images according to the Rayleigh criterion are the center of the Airy disk of a certain focus image and the first dark ring of the Airy disk of the focus image of the adjacent bright spot (the dark concentric ring surrounding the Airy disk). (Airy disk radius r = 0.61λ / NA, where λ: wavelength, NA: numerical numerical aperture Numerical Aperture = n × sin θ). When the measurement light reflected by the fixed reflection surface and the measurement light reflected by the movable reflection surface satisfy this condition, the phase of the two measurement lights is different by π [rad.], So that the interference fringes are canceled out. Therefore, an interference image (interferogram) with high definition cannot be obtained. In other words, if the measurement light reflected by the fixed reflection surface and the measurement light reflected by the movable reflection surface do not satisfy the above conditions, an interference image of both measurement lights can be obtained although the sharpness is lowered.

  In the spectral characteristic measuring apparatus according to the present invention, since the object light beam is divided into two, the effective NA of the object light beam reflected by each of the movable reflecting surface and the fixed reflecting surface is half of the NA of the lens. In other words, the effective N.A. of the object luminous flux is 1/2 times that of the lens, and the allowable value can be obtained by 1.22 × λ / N.A. That is, the distance between the condensing positions of the measurement light reflected by the fixed reflection surface and the measurement light reflected by the movable reflection surface on the imaging surface is the limit of decomposition of the two images according to the Rayleigh criterion 1.22 × λ Narrower than / NA is required. Therefore, 1.22 × λ / NA or a value smaller than this (for example, λ / NA) is an allowable value for forming the interference light of the measurement light on the imaging surface, and the distance between the centers of the two Airy disks. Depending on whether or not is larger than the allowable value, it may be used as an index for determining whether or not the fixed reflecting surface and the movable reflecting surface are relatively inclined.

  According to the present invention, the movable reflection with respect to the fixed reflection surface based on the detection result of the light detection unit that detects the intensity of the measurement light reflected by the fixed reflection surface and the movable reflection surface and collected on the imaging surface. It can be determined whether or not the surface is relatively inclined. And when it is judged that the movable reflective surface is inclined relative to the fixed reflective surface, the fixed reflective surface and the movable reflective surface are used by using the first jig and / or the second jig. Since the direction of both reflecting surfaces can be aligned by adjusting the tilt, an accurate and reproducible interferogram can be acquired.

The figure explaining a mode that the measurement light radiate | emitted from the sample surface by the spectral characteristic measuring apparatus is condensed on an imaging surface by an imaging lens, after being reflected by the fixed reflective surface and the movable reflective surface. The figure which shows the relationship between the amount of angular deviations between a fixed reflective surface and a movable reflective surface, the focal distance of an imaging lens, and the deviation | shift amount of the condensing position on an imaging surface. Explanatory drawing of the Airy disk formed on an image plane when the amount of angular deviations between a fixed reflective surface and a movable reflective surface is zero. Explanatory drawing of the Airy disk formed on an image plane when the amount of angle shifts between a fixed reflective surface and a movable reflective surface is (theta). 1 is a schematic configuration diagram of a spectral characteristic measuring apparatus according to an embodiment of the present invention. The perspective view which shows the whole structure of a phase shifter. The figure which shows the structure of a 1st jig | tool. It is a figure for demonstrating the discrimination | determination method of 1st Example, and the inclination of a picked-up image (a) and a mid-infrared image (b) of a to-be-measured object (person), and a fixed reflective surface and a movable reflective surface is substantially the same. An example of an interferogram (c) of measurement light at a certain time and a spectrum (d) obtained by Fourier transforming this interferogram are shown. The figure which shows the change of an interferogram when changing the relative angular deviation | shift amount between a fixed reflective surface and a movable reflective surface gradually. It is a figure for demonstrating the discrimination method of 2nd Example, and is formed on the schematic surface (a) of the spectral characteristic measuring apparatus of the state which installed the adjustment member which has a pinhole in an object surface, and an image plane Bright spot image (b). The figure which shows the mode of the movement of the bright spot image when changing the screwing amount of the screw of a 1st jig | tool. The figure which shows the mode of the movement of a bright spot image when changing the screwing amount of the screw of a 2nd jig | tool. Explanatory drawing of the relationship between the angle deviation | shift amount of a fixed reflective surface and a movable reflective surface, and the deviation | shift amount of a condensing position. Explanatory drawing of how to obtain | require adjustment target value. Explanatory drawing of how to obtain | require the positional offset amount from an adjustment target value to a luminescent spot image. The modification of a 1st jig | tool.

  Hereinafter, specific embodiments of the present invention will be described with reference to FIGS. FIG. 5 shows a schematic overall configuration of the spectral characteristic measuring apparatus according to the present embodiment. The spectral characteristic measuring apparatus includes an objective lens 10, a phase shifter 11, an imaging lens 12, and a connection between the imaging lens 12. A CCD camera 13 having a light receiving surface located on the image plane, and a control device 14 for controlling detection signal processing of the CCD camera 13 and driving of the phase shifter 11 are provided. In this embodiment, the objective lens 10 functions as an introduction optical system, the imaging lens 12 functions as an imaging optical system, and the CCD camera 13 functions as a light detection unit.

  The CCD camera 13 includes a plurality of two-dimensionally arranged detection pixels that detect the intensity of light received by the light receiving surface. The control device 14 obtains an interferogram from the detection signal of the CCD camera 13, and mathematically Fourier transforms the interferogram to obtain a spectral characteristic (spectrum) that is a relative intensity for each wavelength of the measurement light. From the detection signal of the CCD camera 13, a determination unit 142 that determines the positional relationship between the fixed mirror unit 111 and the movable mirror unit 112 constituting the phase shifter 11, a processing result of the processing unit 141, a determination result of the determination unit 142, and the like are output. An output device 143 such as a display or a printer is provided.

  As shown in FIG. 6, the phase shifter 11 includes a fixed mirror unit 20, a movable mirror unit 30, and a drive mechanism 40 that drives the movable mirror unit 30. The fixed mirror unit 20 is fixed to a support plate 50 fixed to a casing (not shown) of the spectral characteristic measuring device, and has a fixed reflection surface 201 and an L-shaped holding for holding the fixed reflection surface 201. It comprises a tool 202 and a first jig 203 for attaching the holder 202 to the support plate 50. The movable mirror unit 30 includes a movable reflective surface 301, an L-shaped holder 302 that holds the movable reflective surface 301, and a second jig 303 for attaching the holder 302 to the drive mechanism 40. ing.

  Both the fixed reflection surface 201 and the movable reflection surface 301 are installed with an inclination of about 45 degrees with respect to the optical axis of the measurement light traveling from the objective lens 10 toward the phase shifter 11. The movable mirror unit 30 is moved in the direction indicated by the arrow H by the drive mechanism 40. In addition, although the fixed mirror part 20 and the movable mirror part 30 may be arrange | positioned in any of upper and lower sides, here the fixed mirror part 20 is arrange | positioned at the upper side and the movable mirror part 30 is arrange | positioned at the lower side.

Next, the configuration of the first jig 203 will be described with reference to FIGS. 6 and 7. The first jig 203 is composed of three screws S1 to S3 and three sets of washers W1 to W3. The three screws S1 to S3 are inserted into three screw holes respectively formed in the holder 202 and the support plate 50, and the three sets of washers W1 to W3 are located between the holder 202 and the support plate 50. The shafts of the screws S1 to S3 are inserted. One of the three screw holes is formed on one side of the first axis (z axis) parallel to the fixed reflecting surface 201 and perpendicular to the optical axis of the measurement light, and the screw S1 is inserted into the screw hole. Has been. The remaining two screw holes are formed on the other side of the first shaft, and screws S2 and S3 are inserted through these screw holes. The distance from the first shaft to the screw hole on one side is equal to the distance from the screw hole on the other side. Therefore, the holder 202 is adjusted to the first by adjusting the screwing amount of the screw S1 into the screw hole. It rotates around the axis, and the inclination of the fixed reflecting surface 201 changes accordingly.
The second jig 303 basically has the same configuration as the first jig 203, but rotates the holder 302 around a second axis that is parallel to the movable reflecting surface 301 and orthogonal to the first axis. Thus, the inclination of the movable reflecting surface 301 is adjusted.

For example, if the amount of change in the inclination (angle) of the fixed reflecting surface 201 when the screw amount of the screw S1 into the screw hole is changed by M [mm] is θ [rad.], A line connecting the screw S2 and the screw S3 When the distance between the minute and the screw S1 is P, θ is expressed by the following equation (2).
Δθ = tan ⁻¹ (M / P) (2)

  Therefore, the screwing amount M necessary for changing the inclination of the fixed reflecting surface 201 by the angle θ can be obtained from the equation (2). Further, since the screwing amount when the screw S1 is rotated once is determined by the pitch of the screw thread, the rotation amount of the screw S1 can be obtained from the screwing M and the screw thread pitch.

Next, a method for determining whether or not the movable reflective surface 301 is inclined relative to the fixed reflective surface 201 in the spectral characteristic measuring apparatus will be described.
[Example 1]
FIG. 8B introduces measurement light (mid-infrared light) emitted from the subject when the subject shown in FIG. 8A is irradiated with mid-infrared light into the spectral characteristic measurement apparatus. FIG. 4 shows a mid-infrared image obtained by processing detection signals of a plurality of detection pixels of the CCD camera 13. At this time, if the inclinations of the fixed reflection surface 201 and the movable reflection surface 301 are substantially the same, the interferogram of the measurement light can be acquired from all the detection pixels, and the spectrum is obtained by Fourier-transforming the interferogram. Can be requested. For example, FIG. 8C shows an interferogram acquired from detection pixels corresponding to two points in the mid-infrared image shown in FIG. 8B, and FIG. 8D shows a Fourier transform of these interferograms. The spectrum obtained is shown.

  On the other hand, when one of the fixed reflecting surface 201 and the movable reflecting surface 301 is inclined and the amount of angular deviation between the reflecting surfaces is increased, the sharpness of the interferogram deteriorates as shown in FIG. Therefore, in this embodiment, the determination unit 142 determines whether the fixed reflection surface 201 and the movable reflection surface 301 are relatively inclined based on the shape of the interferogram obtained by the processing unit 141, and the determination result. Is output to the output device 142. For example, the interferogram when the interval between the collection positions of the measurement light reflected by the fixed reflecting surface 201 and the movable reflecting surface 301 is the allowable value described in paragraph [0015] is experimentally or computationally calculated in advance. Then, it is determined whether or not the fixed reflecting surface 201 and the movable reflecting surface 301 are relatively inclined by comparing the shape of the interferogram with the shape of the obtained interferogram.

  The user who sees the determination result output to the output device 143 rotates the screw S1 of the first jig 203 or the second jig 303 to change the relative inclination of the fixed reflecting surface 201 and the movable reflecting surface 301. Can be adjusted. If the interferogram is displayed on the output device 143 during the adjustment work by the user, the optimum adjustment can be performed while watching the change in the shape of the interferogram.

[Second Embodiment]
In this embodiment, as shown in FIG. 10, an adjustment member having a pinhole with a diameter of about spatial resolution (= 1.22λ / NA) is installed on the object plane. At this time, detection from the CCD camera 13 is performed. It is determined from the image obtained by processing the signal (FIG. 10B) whether or not the fixed reflective surface 201 and the movable reflective surface 301 are relatively inclined.

  That is, in this embodiment, the measurement light emitted from the pinhole is reflected by the fixed reflecting surface 201 and the movable reflecting surface 301, and then forms bright spot images P1 and P2 by the imaging lens, respectively. When the movable reflective surface 301 is inclined relative to the fixed reflective surface 201, the bright spot images P1 and P2 are formed at different positions as shown in FIG. The image P1 and the bright spot image P2 are overlapped. Therefore, the determination unit 142 determines whether the fixed reflection surface 201 and the movable reflection surface 301 are relatively inclined based on the formation positions of the bright spot images P1 and P2.

  Further, when the screw S1 of the first jig 203 is rotated from the state shown in FIG. 10B to rotate the holder 202 around the first axis, one of the bright spot images moves. For example, if the bright spot image P1 moves in the direction indicated by the arrow in FIG. 11, the axis extending in this direction is the coordinate axis on the image plane that can be adjusted by the first jig 203 (hereinafter referred to as “A coordinate axis”). Become. Similarly, if the other bright spot image P2 is moved in the direction indicated by the arrow in FIG. 12 by rotating the screw S1 of the second jig 303 and rotating the holder 302 around the second axis, this direction will be indicated. The extending axis is a coordinate axis (hereinafter referred to as “B coordinate axis”) on the image plane that can be adjusted by the second jig 303.

  As shown in FIG. 13, the intersection of the A coordinate axis and the B coordinate axis is an adjustment target value indicating a state in which the inclination of the fixed reflecting surface 201 and the movable reflecting surface 301 is not shifted. When the adjustment target value is obtained, as shown in FIG. 14, the positional deviation amounts ΔP1 and ΔP2 with respect to the adjustment target amount value on the imaging plane can be obtained for each of the bright spot images P1 and P2. From the amounts ΔP1 and ΔP2 and the above formulas (1) and (2), the amount of height movement of the screw S1 of the first jig 203 and the screw S1 of the second jig 303 can be obtained, and fixed reflection can be easily performed. The inclination of the surface 201 and the movable reflecting surface 301 can be adjusted.

  In the above-described embodiment, the first jig 203 (or the second jig 303) is composed of three screws S1 to S3 and three sets of washers W1 to W3. However, as shown in FIG. Instead of the washers inserted in the shaft portions of the screws S2 and S3, the support plate 50 (or the drive mechanism 40) may be provided with a protrusion 60 that makes point contact with the holder 202. In this case, if the lower surfaces of the heads of the screws S1 to S3 are chamfered, the holder 202 (or the holder 302) is moved around the first axis (or the second axis) when the screwing amount of the screw S1 is changed. Can be rotated smoothly.

DESCRIPTION OF SYMBOLS 10 ... Objective lens 11 ... Phase shifter 12 ... Imaging lens 13 ... CCD camera 14 ... Control device 141 ... Processing part 142 ... Processing part 143 ... Output device 20 ... Fixed mirror part 201 ... Fixed reflection surface 202 ... Holder 203 ... First DESCRIPTION OF SYMBOLS 1 Jig 30 ... Movable mirror part 301 ... Movable reflective surface 302 ... Holder 303 ... 2nd jig 40 ... Drive mechanism 50 ... Support plate S1-S3 ... Screw W1-W3 ... Washer

Claims (4)

a) a fixed reflecting surface and a movable reflecting surface arranged side by side;
b) an introduction optical system that guides measurement light emitted from the measurement point of the object to be measured to the fixed reflection surface and the movable reflection surface;
c) Image formation for condensing the measurement light introduced into the fixed reflection surface and reflected by the fixed reflection surface and the measurement light introduced into the movable reflection surface and reflected by the movable reflection surface on the image formation surface, respectively. Optical system,
d) a light detection unit for detecting the intensity of the light collected on the imaging surface, having a plurality of detection pixels arranged two-dimensionally on the imaging surface;
e) Processing for obtaining an interferogram of the measurement light based on a change in light intensity detected by the light detection unit by moving the movable reflecting surface, and acquiring a spectrum by Fourier transforming the interferogram In a spectral characteristic measuring device comprising a unit,
A spectral characteristic measuring apparatus comprising: a determination unit configured to determine whether or not the movable reflective surface is inclined relative to the fixed reflective surface based on a detection result of the light detection unit. further,
A first jig for adjusting the amount of inclination of the movable reflecting surface around a first axis parallel to the movable reflecting surface; and a second jig around a second axis perpendicular to the first axis and parallel to the fixed reflecting surface. The spectral characteristic measuring apparatus according to claim 1, further comprising a second jig for adjusting an inclination amount of the fixed reflecting surface. An adjusting member having a pinhole, which is installed on the surface of the object to be measured;
The introducing optical system guides the measurement light emitted through the pinhole to the fixed reflecting surface and the movable reflecting surface, thereby determining the discriminating means based on the position of the bright spot image formed on the imaging surface. The spectral characteristic measuring apparatus according to claim 1, wherein it is determined whether or not the movable reflective surface is inclined relative to the fixed reflective surface. a) a fixed reflecting surface and a movable reflecting surface arranged side by side;
b) an introduction optical system that guides measurement light emitted from the measurement point of the object to be measured to the fixed reflection surface and the movable reflection surface;
c) Image formation for condensing the measurement light introduced into the fixed reflection surface and reflected by the fixed reflection surface and the measurement light introduced into the movable reflection surface and reflected by the movable reflection surface on the image formation surface, respectively. Optical system,
d) a light detection unit for detecting the intensity of the light collected on the imaging surface, having a plurality of detection pixels arranged two-dimensionally on the imaging surface;
e) Processing for obtaining an interferogram of the measurement light based on a change in light intensity detected by the light detection unit by moving the movable reflecting surface, and acquiring a spectrum by Fourier transforming the interferogram In a spectral characteristic measuring device comprising a unit,
A method for adjusting a spectral characteristic measuring apparatus, comprising: adjusting a relative inclination of the movable reflective surface with respect to the fixed reflective surface based on a detection result of the light detection unit.