JPH0650012U - Beam splitter device - Google Patents

Abstract

(57) [Abstract] [Purpose] The present invention positions and fixes a beam splitter with high accuracy without requiring high processing accuracy. [Structure] The beam split (10) formed by the first prism (11) and the second prism (12) is attached to a prism fixing base (2
It is attached to the mounting surface (23, 24) that is formed so as to be inclined to 0). In this case, the first prism (11) and the second prism (1
Since the widths of (2) and (2) are different from each other, one of the prisms (11), for example, has a surface portion (14, 15) that does not become a light flux reflecting surface (13) without making surface contact, and this surface portion (14 , 15) contacts the mounting surface (23, 24) of the prism fixing base (20). As a result, the beam splitter (10) is positioned such that its light flux reflecting surface (13) is perpendicular to the reflected light axis with respect to the incident light axis.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention is applied to optical instruments such as microscopes and measuring instruments, and relates to a beam splitter device that splits a light beam into two directions.

[0002]

[Prior art]

 Among beam splitters applied to optical instruments such as microscopes and measuring instruments, there are some beam splitters arranged in a parallel light flux region within the optical instrument. Such a beam splitter is described, for example, in Japanese Patent Application No. 3-284979, and FIG. 7 is a configuration diagram thereof. This beam splitter is formed by surface-contacting the bottom surfaces of prisms 1 and 2 each having an isosceles triangular cross-section, and this surface-contacting portion serves as a light beam reflecting surface 3. Therefore, a part of the light incident on the beam splitter along the incident optical axis 4 is reflected by the light flux reflecting surface 3 and is branched along the reflected light axis 5, while the other light is transmitted through the light flux reflecting surface 3. Then, the light is split in the direction coaxial with the incident optical axis 4.

In such a beam splitter, it is necessary to position and fix the reflected optical axis 5 with high accuracy so that the reflected optical axis 5 becomes a direction perpendicular to the incident optical axis 4, and this requires a light beam incident surface 6 of the beam splitter. The angle β formed by the normal line to the incident optical axis 4 is accurately fixed.

Specifically, the base angle α of the isosceles triangle in each of the prisms 1 and 2 is to be processed with high precision. Along with this, as shown in FIG. Since the prism fixing base 7 is fixed to the light incident surface 6, the inclination angle β ′ of the mounting surface 8 of the prism fixing base 7 that comes into contact with the light flux incident surface 6 is processed with high precision.

[0005]

[Problems to be solved by the device]

 As described above, in order to accurately position and fix the reflected optical axis 5 of the beam splitter in the vertical direction with respect to the incident optical axis 4, the base angles α of the prisms 1 and 2 are precisely processed, and The inclination angle β ′ of the mounting surface 8 of the prism fixing base 7 must be machined with high precision, which increases the manufacturing cost. Therefore, an object of the present invention is to provide a beam splitter device capable of accurately positioning and fixing the beam splitter without requiring high processing accuracy.

[0006]

[Means for Solving the Problems]

 The present invention provides a first prism having an isosceles triangular cross section, a second prism having an isosceles triangular cross section and a width different from that of the first prism, and the first prism and the second prism. A beam splitter having a light beam reflecting surface formed by making surface contact with a predetermined surface of the beam splitter. The beam splitter is formed to have an inclination to position the incident optical axis at a right angle to the reflected optical axis of the beam splitter, and the first or second prism. A beam splitting device that achieves the above object by including a prism fixing base having a mounting surface that is in contact with a light flux reflecting surface of one of the prisms and a surface on the same plane.

[0007]

[Action]

 By providing such means, the beam splitter formed by the first prism and the second prism is attached to the mounting surface of the prism fixing base that is formed to be inclined. In this case, since the widths of the first prism and the second prism are different from each other, one of the prisms has a surface portion that does not come into surface contact and does not serve as a light beam reflecting surface. Contact a surface. As a result, the beam splitter is positioned such that its light flux reflecting surface is perpendicular to the reflected light axis.

[0008]

【Example】

 Hereinafter, a first embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is an external configuration diagram of the beam splitter device. The beam splitter 10 includes a first prism 11 having an isosceles triangular shape as shown in a cross-sectional shape in the direction of arrow (a) in FIG. 2, and a second prism 1 2 having an isosceles triangular cross-sectional shape similar to the first prism 11. Are in surface contact with each bottom surface.

Further, the first prism 11 is formed to have a width L1 as shown in the external view seen from the arrow (b) direction in FIG. 3, and the other second prism 12 is wider than the width L1 of the first prism 11. The width L2 is narrower by a predetermined width.

In this manner, the light flux reflecting surface 13 is formed by bringing the prisms 11 and 12 into surface contact with each other. It should be noted that in FIG. 1, the light flux reflecting surface 13 is shown by diagonal lines. In this case, since the widths L1 and L2 of the prisms 11 and 12 are different as described above, the abutting surfaces 14 and 15 are formed on the bottom surface of the first prism 11 on both sides of the light flux reflecting surface 13. In addition, in FIG. 1, the contact surfaces 14 and 15 are indicated by diagonal lines.

On the other hand, a U-shaped or U-shaped prism fixing base 20 is provided, on which the beam splitter 10 is positioned and fixed. The prism fixing base 20 has mounting surfaces 23 and 24 formed on the side surfaces 21 and 22, respectively. These mounting surfaces 23 and 24 are formed at an inclination angle θ1 that positions the incident optical axis with respect to the reflected optical axis of the beam splitter 10 at a right angle.

A screw hole 25 and holes 26, 27 for inflowing an adhesive are formed on one side surface 22, and a fixing screw 28 is screwed into the screw hole 25. Has become.

The beam splitter 10 is fixed to the prism fixing base 20. This fixes the contact surfaces 14 and 15 of the beam splitter 10 to the mounting surfaces 23 and 24, respectively. It is supposed to do.

More specifically, first, when the beam splitter 10 is attached to the prism fixing base 20, the abutting surfaces 14 and 15 of the first prism 11 are attached to the attaching surfaces 23 and 24 of the prism fixing base 20. To be provided in contact with.

Next, the fixing screw 28 is screwed into the screw hole 25, that is, by screwing, the side surface 11 a of the first prerhythm 11 is pressed against the side surface 21 of the prism fixing base 20. The dimensions of the second prism 12 are determined so as not to come into contact with the side surface 29 of the prism fixing base 20 in response to the pushing of the first prism 11. Next, the adhesive is poured from the holes 26 and 27, and the prisms 11 and 12 are bonded and fixed to the prism fixing base 20.

With such a configuration, the accuracy of arranging the incident optical axis vertically with respect to the reflected optical axis of the beam splitter 10 depends only on the processing accuracy of the inclination angle θ1 of each mounting surface 23, 24. , The prisms 11 and 12 do not depend on the processing accuracy of the base angle. Therefore, the manufacturing cost can be reduced because it does not directly depend on the processing accuracy of the base angles of the prisms 11 and 12. Further, since the vicinity of the centers of the prisms 11 and 12 are fixed with an adhesive, the adhesive force can reduce the occurrence of cracks in the prisms 11 and 12.

Further, since the positioning and fixing of the beam splitter 10 may be performed by attaching the prisms 11 and 12 in contact with the attachment surfaces 23 and 24, the beam splitter 10 can be incident on the reflected optical axis of the beam splitter 10 with high accuracy by a simple operation. The optical axis can be positioned at a right angle. Next, a second embodiment of the present invention will be described.

FIG. 4 is an external configuration diagram of the prism fixing base 30 of the beam splitter device, and FIGS. 5 and 6 are configuration diagrams of the beam splitter 40 attached and fixed to the prism fixing base 30.

As shown in FIG. 5, the beam splitter 40 includes a first prism 41 having an isosceles triangular cross section, and a second prism 42 having an isosceles triangular cross section similar to the first prism 41. Are in surface contact with each bottom surface.

As shown in FIG. 6, the first prism 41 has a width L3, and the other second prism 42 has a width L4 narrower than the width L3 of the first prism 41 by a predetermined width. .

In this way, the light flux reflecting surface 43 is formed by bringing the prisms 41 and 42 into surface contact with each other. In this case, as shown in FIG. 6, the prisms 41 and 42 are arranged so that their respective side surfaces are aligned so as to be flush with each other. Further, since the respective widths of the prisms 41 and 42 are different as described above, the abutting surface 44 is formed on one side of the light flux reflecting surface 43 on the bottom surface of the first prism 41.

A beam splitter 40 is positioned and fixed on the prism fixing base 30. In this prism fixing base 30, each mounting surface 32 is formed on one side surface 31. The mounting surface 32 is formed at an inclination angle θ2 that positions the incident optical axis of the beam splitter 40 at a right angle to the reflected optical axis. A screw hole 34 is formed in the other side surface 33, and a fixing screw 35 is screwed into the screw hole 34.

The beam splitter 40 is fixed to the prism fixing base 30. This fixes the contact surface 44 of the beam splitter 40 to the mounting surface 32 by contacting it. . More specifically, first, the abutting surface 44 of the first prism 41 forming the beam splitter 40 is provided in contact with the mounting surface 32 of the prism fixing base 30. Next, the fixing screw 35 is screwed into the screw hole 34 to press the side surface 41 a of the first prerhythm 41 against the side surface 31 of the prism fixing base 30.

With such a configuration, the accuracy of arranging the incident optical axis vertically with respect to the reflected optical axis of the beam splitter 40 depends on the processing accuracy of the inclination angle θ2 of the mounting surface 32, and each prism 41, Since it does not directly depend on the machining accuracy of the bottom angle of 42, the manufacturing cost can be reduced.

Further, since the positioning and fixing of the beam splitter 10 may be carried out by mounting each prism 41 in contact with the mounting surface 32, the incident optical axis with respect to the reflected optical axis of the beam splitter 30 can be accurately made at right angles by a simple work. Can be positioned. The present invention is not limited to the above embodiments, and may be modified without changing the gist thereof.

[0027]

[Effect of device]

 As described in detail above, according to the present invention, it is possible to provide a beam splitter device capable of accurately positioning and fixing a beam splitter without requiring high processing accuracy.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing a first embodiment of a beam splitter device according to the present invention.

FIG. 2 is a configuration diagram of a beam splitter in the same apparatus as seen from a lateral direction.

FIG. 3 is a configuration diagram showing each prism width in a beam splitter of the same apparatus.

FIG. 4 is a configuration diagram showing a second embodiment of a beam splitter device according to the present invention.

FIG. 5 is a configuration diagram of a beam splitter in the same apparatus as seen from a lateral direction.

FIG. 6 is a configuration diagram showing each prism width in a beam splitter of the same apparatus.

FIG. 7 is a configuration diagram of a conventional beam splitter.

FIG. 8 is a diagram for explaining optical axis positioning of the beam splitter.

[Explanation of symbols]

10, 40 ... Beam splitter, 11, 41 ... First prism, 12, 42 ... Second prism, 13, 43 ... Light flux reflecting surface, 14, 15, 44 ... Abutting surface, 20, 30 ... Prism fixing base, 21 , 22 ... Side surface, 23, 24, 32 ... Mounting surface, 25, 34 ... Screw hole, 26, 27 ... Hole, 28,
35 ... Fixed screw.

Claims (1)

[Scope of utility model registration request] 1. A first prism having a cross section of an isosceles triangle, a second prism having a cross section of an isosceles triangle and having a width different from that of the first prism, and the first prism.
A beam splitter, in which predetermined surfaces of the prism and the second prism are in surface contact with each other to form a light flux reflecting surface, is fixed, and the beam splitter is formed to have an inclination for positioning the incident optical axis at a right angle to the reflected optical axis of the beam splitter. First or second
A beam splitter device, comprising: a prism fixing base having a mounting surface that is in contact with a surface on the same plane as the light flux reflecting surface of one of the prisms.