JPS62227110A - Assembling method for concave surface optical element - Google Patents

Abstract

PURPOSE:To secure the parallelism between the surface of a concave surface optical element and a rotating shaft and to easily obtain the concave optical element by adhering the concave optical element on a base atop the rotating shaft while fixing the position relation between the surface of a concave diffraction grating or concave optical element like a concave mirror and the rotating shaft. CONSTITUTION:A V groove 36 for positioning the rotating shaft which rotates the concave diffraction grating is formed in a main jig body 34 and the V groove 36 and the plane which contains projection parts 32a-232d of a convex surface member 30 are fixed in parallel position relation. Further, the main jig body 34 is provided with a pressure member which presses the concave diffraction grating brought into contact with the concave surface member 30 toward the convex surface member 30. The peripheral part of the surface 4 of the concave diffraction grating 2 is brought into contact with projection parts 32a-32d of the convex surface member 30 of the jig and the pressure member 38 presses the concave diffraction grating 2 toward the convex surface member 30. Further, the gap between the rotating shaft 8 where a diffraction grating base 10 is fixed atop is fitted in and positioned in the V groove 36 of the main jig body 34. In this state, the lower end surface of the concave surface diffraction grating 2 and the diffraction grating base 10 is fixed with an adhesive 12.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method of assembling concave optical elements such as concave diffraction gratings or concave mirrors used in spectrometers, spectrophotometers or spectrofluorometers. In particular, the present invention relates to an assembly method that includes a step of bonding such a concave optical element onto a table at the tip of a rotating shaft using an adhesive.

(Prior Art) FIG. 7 shows a conventional method for assembling a concave optical element. In the conventional example and the embodiment of the present invention, a concave diffraction grating will be explained as an example of the concave optical element, but in the case of a concave mirror, is exactly the same.

In FIG. 7, 2 is a concave diffraction grating, 4 is its front surface or diffraction surface, and 6 is its back surface.

Reference numeral 8 denotes a rotating shaft, and a diffraction grating stand 10 as a support is fixed to the tip of the rotating shaft 8, and the lower end surface of the concave diffraction grating 2 is adhered onto the diffraction grating stand 10 with an adhesive 12.

14 is a jig used in the conventional method of assembling the concave diffraction grating 2. The jig 14 is integrally provided with a surface 16 in close contact with the back surface 6 of the concave diffraction grating 2 and a V-groove 18 for positioning the rotating shaft 8 so as to maintain a mutually parallel positional relationship.

To assemble the concave diffraction grating 2 using this jig 14,
The concave diffraction grating 2 and the diffraction grating stand 10 are bonded together with an adhesive 12 while the mutual positional relationship between the rotating shaft 8 and the back surface 6 of the concave diffraction grating 2 is fixed by the V groove 18 of the jig 14.

(Problems to be Solved by the Invention) In the concave diffraction grating 2 assembled in this way, parallelism between the back surface 6 and the front surface 4 is required, and the center position of the surface 4 of the concave diffraction grating 2 is Although it is required to match the center of the outer shape of the diffraction grating 2, it is difficult to achieve mechanical precision such as parallelism in the concave diffraction grating 2, and it is also expensive. It has become.

This situation also applies to concave mirrors.

In order to mount a concave diffraction grating assembly with insufficient mechanical precision on a base, as shown in FIG.
The rotating shaft 8 is attached to the mount 22 via bearings 24 and 26.
be attached rotatably. An adjustment screw 28 is provided between the mount 22 and the base 20. The adjustment screw 28 adjusts the swivel 30 of the concave diffraction grating 2 and the direction of the concave diffraction grating 2.

If an inexpensive spectrometer is to be produced, it is desirable to eliminate the adjustment mechanism shown in FIG. 8 as much as possible. This situation also exists when assembling concave mirrors.

An object of the present invention is to provide an assembly method that does not require three-dimensional adjustment of a concave optical element using a mount.

(Means for Solving the Problems) The assembly method of the present invention includes a convex member that contacts at least a portion of the concave surface of a concave optical element and whose contact portion has the same curvature as the concave surface, and a convex member that rotates the concave optical element. Using a jig in which a member for positioning the rotational axis is integrally provided while maintaining a mutual positional relationship, the concave optical element is fixed in the relative position of the concave surface of the concave optical element and the rotational axis. Glue it onto the support stand at the tip of the rotating shaft.

(Example) FIG. 1 shows an example of a jig used in the method of the present invention.

Reference numeral 30 denotes a convex member having white parts 32a to 32d of the same curvature as the surface (diffraction surface) of a square concave diffraction grating. Close contact with the department. The convex member 20 is fixed to the jig main body 34.

The jig main body 34 is provided with a V-groove 36 for positioning the rotation axis for rotating the concave diffraction grating, and the groove 36 and the plane containing the white portions 32a to 32d of the convex member 30 are in a parallel positional relationship. is fixed.

Also on the jig main body 34. A suppressing member 38 is provided for pushing the back surface of the concave diffraction grating that is in close contact with the concave member 30 in the direction of the convex member 30 .
0 biases the concave diffraction grating in a direction toward the convex member 30.

The convex member 30 can be formed by polishing a rectangular member using a polishing plate having the same curvature as the concave diffraction grating that is assembled.

FIG. 2 shows a method of bonding a concave diffraction grating to a diffraction grating stand at the tip of a rotating shaft using the jig shown in FIG. 1.

The peripheral part of the surface 4 of the concave diffraction grating 2 is connected to the convex member 30 of the jig.
The concave diffraction grating 2 is pressed in the direction of the convex member 30 by the suppressing member 38.

Of the convex member 30, the white portions 32a to 32d are in contact with the concave diffraction grating 2, as shown in FIG.

Further, the rotating shaft 8 to which the diffraction grating stand 10 is fixed at the tip is fitted into the V-groove 36 of the jig main body 34 for positioning.

In this state, the gap between the lower end surface of the concave diffraction grating 2 and the diffraction grating stand 10 is bonded and fixed with adhesive 12.

An example of a convex member 30 of a jig used when the concave diffraction grating 2 is circular is shown in FIGS. 4 and 5.

The convex member 30 in FIG. 4 is obtained by polishing the periphery of a disc with a polishing plate having the same curvature as the concave diffraction grating.
A shaded portion 40 has the same curvature as the concave diffraction grating and is in close contact with the surface of the concave diffraction grating.

The convex member 30 in FIG. 5 is located at three locations 42a to 4 around the disk.
2c is protruded, and its portions 42a to 42C are polished with a polishing plate having the same curvature as the concave diffraction grating, and it is in close contact with the surface of the concave diffraction grating at three locations 42a to 42C.

(Effects of the Invention) In the method of the present invention, a concave optical element, such as a concave diffraction grating or a concave mirror, is bonded onto a stand at the tip of the rotating shaft while the relative position of the surface of the concave optical element and the rotating shaft is fixed.

According to this method, the surface and the back surface of the concave optical element do not have to be parallel in principle, that is, as shown in FIG. Even if the plane 4a including the four side corners and the back surface 6 are tilted,
The parallelism between the surface 4 of the concave optical element and the axis of rotation 8 is ensured. Therefore, the concave optical element can be manufactured easily.

Further, even if the center of the concave optical element is not in the middle of the outer shape of the concave optical element, adjustment of the concave optical element is not necessary.

Consequently, in the concave optical element assembly according to the invention, as long as the curvatures of the concave surfaces are the same.

Since the centers of curvature of the concave optical elements are located at the same point, compatibility is excellent.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing an example of a jig used in the present invention;
Fig. 2 is a sectional view showing how to assemble a concave diffraction grating using the jig shown in Fig. 1, Fig. 3 is a plan view showing the convex member of the jig shown in Fig. 1, and Figs. 4 and 5 are A plan view showing convex members of other jigs used in the present invention, FIG. 6 is a sectional view showing a concave diffraction grating assembly assembled by the method of the present invention, and FIG. 7 shows a conventional assembly method. Cross-sectional view. FIG. 8 is a sectional view showing a conventional method of mounting a concave diffraction grating assembly. 2...Concave diffraction grating, 4...Surface. 8...Rotating shaft, 30...Convex surface member, 32a to 32d, 40, 42a to 42cm convex portion, 36...V groove.

Claims (1)

[Claims] (1) A convex member that contacts at least a portion of the concave surface of the concave optical element and whose contact portion has the same curvature as the concave surface, and a member that positions the rotation axis for rotating the concave optical element maintain a mutual positional relationship. A concave optical element, in which the concave optical element is bonded onto a support at the tip of the rotational axis while fixing the relative position of the concave surface of the concave optical element and the rotational axis using a jig integrally provided with the concave optical element. How to assemble.