FIXED MIRROR, INTERFEROMETER, AND FOURIER TRANSFORM SPECTROPHOTOMETER

Abstract

Provided is a fixed mirror unit capable of adjusting the inclination of a reflection surface and moving the reflection surface in a direction intersecting with the reflection surface with a simple configuration, an interferometer equipped with the fixed mirror unit, and a Fourier transform spectrophotometer. The fixed mirror unit 8 is provided with a plurality of actuators 83 for axially displacing the mirror 87. By displacing the mirror 87 by different amounts of displacements with the plurality of actuators 83, the angle of the reflection surface 87A can be adjusted, while by displacing the mirror 87 by the same amount of displacement with the plurality of actuators 83, the reflection surface 87A can be moved while keeping the angle of the reflection surface 87A constant. As a result, with a simple configuration, the angle of the reflection surface 87A can be adjusted and the reflection surface 87A can be moved along the axial direction.

Claims

1. A fixed mirror unit adjusted for an interferometer and configured to reflect light from a light source into first reflected light to interfere the first reflected light with second reflected light reflected by a movable mirror unit from the light source, resulting in interference light, the fixed mirror unit comprising: a mirror having a reflection surface for reflecting light from the light source; and a plurality of actuators each operable to displace the mirror in a direction intersecting with the reflection surface, the displacements of the plurality of actuators allowing the reflection surface to have an adjustable angle by different amounts of displacements of the mirror with the plurality of actuators and the reflection surface to be moved with the angle of the reflection surface kept constant by the same amount of displacements of the mirror with the plurality of actuators.

2. The fixed mirror unit as recited in claim 1, wherein the plurality of actuators is arranged at equal intervals in a circumferential direction with respect to a center position of the reflection surface.

3. The fixed mirror unit as recited in claim 1, wherein the plurality of actuators are each composed of a piezoelectric element.

4. The fixed mirror unit as recited in claim 1, further comprising: a flexure portion connecting the mirror and each of the plurality of actuators, wherein the flexure portion is provided with a secured fixing portion, a displacement portion configured to be displaced in accordance with an operation of each of the plurality of actuators, and a beam portion which connects the fixing portion and the displacement portion and elastically displaces the displacement portion with respect to the fixing portion.

5. The fixed mirror unit as recited in claim 4, further comprising: an elastic hinge interposed between the flexure portion and the mirror and elastically deformable in a direction intersecting with the reflection surface.

6. An interferometer comprising: the fixed mirror unit as recited in claim 1; a movable mirror unit movable by an amount of displacement larger than an amount of displacement of the mirror in the fixed mirror unit; and a light source configured to emit light to the fixed mirror unit and the movable mirror unit, wherein the reflected light from the fixed mirror unit and the reflected light from the movable mirror unit are interfered with each other to generate interference light.

7. The interferometer as recited in claim 6, further comprising: a main body to which the fixed mirror unit and the movable mirror unit are attached; and a coarse adjustment mechanism configured to change the angle of the reflection surface by adjusting an angle of the fixed mirror unit attached to the main body.

8. A Fourier transform spectrophotometer, comprising: the interferometer as recited in claim 6; and a detector configured to detect reflected light or transmitted light from a sample generated by irradiating the sample with interference light from the interferometer.

Description

DESCRIPTION OF REFERENCE SYMBOLS

[0079] 1: Fourier transform spectrophotometer [0080] 2: interferometer [0081] 3: light source [0082] 4: main body [0083] 6: movable mirror [0084] 8: fixed mirror unit [0085] 9: coarse adjustment mechanism [0086] 12: detector [0087] 82: flexure portion [0088] 83: actuator [0089] 85: elastic hinge [0090] 87: mirror [0091] 87A: reflection surface [0092] 821: fixing portion [0093] 822: displacement portion [0094] 823: beam portion