JPH05164909A - Method for cutting quadrangular prism - Google Patents

Abstract

(57) [Summary] [Object] An object of the present invention is to provide a cutting method for cutting a quadrangular prism exactly at right angles to the longitudinal axis. A reflecting film 20 is provided on the surface of the blade 18 of the dicing saw 16. Further, the laser beam emitting means 24 equipped with the screen 32 having the pinhole 34 is fixed to the parallel plate substrate 10, and the parallel plate glass plate 12 to which the quadratic prism 14 to be cut is adhered is placed on the substrate 10. Then, the reference prism 22, which is a rectangular parallelepiped having an accurate shape, is placed on the glass plate 12 so that one surface thereof contacts the longitudinal surface of the quadratic prism 14 to be cut. Then, the laser beam is emitted toward the reflective film of the dicing saw 16 through the pinhole 34 of the laser beam emitting means 24,
The substrate 10 and the glass plate 12 are arranged so that the reflected light of the reflective film 20 and the reflected light of the reference prism 22 return to the pinhole 34.
Adjust the angle of.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention generally relates to a method of cutting a quadrangular prism, and more particularly to a method of cutting a quadrangular prism having a branch coupling film or a polarization splitting film on a bonding surface of two triangular prisms.

In the field of optical communication or optical transmission, light is used to split a single light beam into two or more light beams or to combine two or more light beams into a single light beam. An optical coupler such as a branch coupling prism is used. With the former function, the transmitted optical signal can be distributed to a plurality of devices, and with the latter function, the signal light of a plurality of channels can be coupled to a single or a plurality of optical transmission lines in the case of multiplex transmission. ..

In the case where the light sources on the transmission side are to be duplicated in order to construct a highly reliable optical communication system, the polarization splitting is performed in order to combine the lights emitted from the two light sources into a common optical transmission line. A prism is used.

This type of optical branching / coupling prism or polarization splitting prism is generally constructed by interposing a branching / coupling film or a polarization splitting film between a pair of transparent prisms. It is created by cutting into pieces.

[0005]

2. Description of the Related Art A conventional method for producing a polarization separation prism will be described with reference to FIG. In addition, the method of creating the optical branching coupling prism is different only in the nature of the intervening film,
Are substantially the same.

As shown in FIG. 4A, after the polarization separation film 5 is deposited on the slope of the glass column 4a having a cross section of an isosceles right triangle, another glass column 4b having the same shape is formed on the slope of the glass column 4a.
The quadrangular prism 4 serving as a base material is formed by adhering to the surface on which is vapor-deposited.

A plurality of the quadrangular prisms 4 thus formed are adhered to each other on the parallel flat glass plate 2 as shown in FIG. Then, visually or using a ruler or the like, the rectangular prism 4 is cut into a predetermined length by the blade 8 of the dicing saw 6 so that the cutting angle θ with respect to the longitudinal axis is 90 °, and FIG. The polarization beam splitter 4'as shown in FIG.

[0008]

However, in the conventional method of cutting a rectangular prism, the squareness at the time of cutting is provided by visual inspection or using a ruler, so that there is an error from a right angle at the time of cutting. There was a problem that it was likely to occur. If such a squareness error occurs, the assembling property may be deteriorated when the polarization beam splitter is incorporated into an optical device.

The present invention has been made in view of the above points, and an object of the present invention is to provide a quadrangular prism which can be cut at a right angle to the longitudinal axis. It is to provide a cutting method.

[0010]

In order to solve the above-mentioned problems, the present invention provides a quadratic prism which is obtained by cutting a quadrangular prism formed by laminating two right-angled prisms at their slopes with a dicing saw. In the cutting method,
A reflective film is provided on the blade surface of the dicing saw, and a laser beam emitting means having a screen having pinholes is fixed to a parallel plate substrate, and a parallel plate glass plate to which a square prism prism to be cut is adhered is formed on the substrate. Put on top,
A reference prism, which is a rectangular parallelepiped having an accurate shape, is placed on the glass plate so that one surface is in contact with the longitudinal surface of the quadratic prism to be cut, and dicing is performed through the pinhole of the laser beam emitting means and the reference prism. A laser beam is emitted toward the reflective film of the saw, and the angle of the substrate and the glass plate is adjusted so that the reflected light of the reflective film and the reflected light of the reference prism return to the pinhole. There is provided a method for cutting a quadrangular prism, wherein the quadratic prism to be cut is cut into a predetermined length by a dicing saw.

[0011]

According to the above-described cutting method of the present invention, since the perpendicularity between the blade surface of the dicing saw and the longitudinal surface of the quadratic prism to be cut is set by using the laser beam, the quadrangular prism to be cut It is possible to cut the prism exactly at right angles to the longitudinal axis.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A method of cutting a rectangular prism according to an embodiment of the present invention will be described below with reference to the drawings. First, the configuration of a cutting jig used in the cutting method of the present invention will be described with reference to FIGS. 1 and 2.

Reference numeral 10 designates a parallel plate substrate.
A laser beam emitting device 24 is fixed to one of the upper ends. The laser beam emitting device 24 includes a holder 26 fixed to the substrate 10, an optical fiber 28 whose end is held by the holder 26, and a lens 30 for converting the laser beam from the optical fiber 28 into a collimated beam.
It is composed of a screen 32 and a pinhole 34 provided at a substantially central portion of the screen 32.

A parallel plate glass plate 12 is further placed on the substrate 10, and a plurality of quadrangular prism prisms 14 to be cut are bonded on the glass plate 12 so that their longitudinal surfaces are in contact with each other. It is glued in.

Further, on the glass plate 12, a reference prism 22 which is a rectangular parallelepiped having an accurate shape is mounted so that one surface thereof is in contact with the surface of the rectangular prism 14 to be cut in the longitudinal direction. A reflective film 20 is provided on the blade 18 of the dicing saw 16.

Hereinafter, a method of cutting a rectangular prism using the above-mentioned cutting jig will be described. First, the glass plate 12 to which the quadratic prism 14 to be cut is bonded is attached to the substrate 10.
The collimated laser beam is emitted toward the reflection film 20 of the dicing saw 16 through the pinhole 34 of the laser beam emitting device 24 without being placed on the top.

Then, the substrate 10 is slightly rotated in the arrow A and B directions so that the reflected light from the reflective film 20 accurately returns to the pinhole 34, and the angle of the substrate 10 with respect to the blade 18 is adjusted. , Reflected light is pinhole 3
The substrate 10 is fixed at the position returning to 4. As a result, the blade 18 of the dicing saw 16 and the upper surface of the substrate 10 are accurately arranged at right angles.

Thus, the substrate 1 for the blade 18
After adjusting the squareness of 0, the glass plate 12 to which a plurality of quadrangular prisms 14 to be cut are adhered is placed on the substrate 10. Then, the reference prism 22 is placed on the glass plate 12 such that one surface thereof is in contact with the surface of the quadrangular prism to be cut 14 in the longitudinal direction.

Then, the laser beam is emitted toward the reflecting film 20 again through the pinhole 34 of the laser beam emitting device 24. Since the reference prism 22 is provided in the middle of the optical path of the laser beam, when the reference surface 22a of the reference prism 22 is not perpendicular to the optical path of the laser beam, the spot of the reflected light from the reference surface 22a is on the screen 32. Will be reflected in. In such a case, by slightly rotating the glass plate 12 in the direction of arrow C,
The reflected return light from the reference surface 22a is accurately pinhole 34.
Adjust to return to.

The blade surface of the dicing saw 16 and the substrate 1
Since the perpendicularity of the 0 to the upper surface has been accurately adjusted by the previous adjustment step, the reflected light from the reflective film 20 on the blade 18 is supposed to return exactly to the pinhole 34, so that the reference prism 22 By adjusting the angle of the glass plate 12 so that the reflected light from the reference surface 22a of the dicing saw 16 accurately returns to the pinhole 34, the longitudinal axis of the quadratic prism 14 to be cut and the blade surface of the dicing saw 16 are accurately adjusted. Can be adjusted to a right angle relationship.

After the adjustment as described above, the glass plate 12 is fixed to the substrate 10, and the dicing saw 16 is rotationally driven to cut the quadratic prism 14 to be cut into a predetermined length. This makes it possible to manufacture a polarization splitting prism (polarization beam splitter) or a light splitting / coupling prism having an exact cubic shape or a rectangular parallelepiped shape.

In the above-mentioned angle adjusting step, when the dicing saw 16 is adjusted while rotating,
Adjustment can be made in consideration of the rotational shake of the dicing saw, and more accurate squareness can be obtained. Reflective film 20
Is applied or affixed to the surface of the blade 18, and is provided annularly around the entire circumference of the blade 18 or the dicing saw 16
When the angle is adjusted while rotating the, it is provided on a part of the blade 18.

In the above-described embodiment, since the squareness between the blade surface and the upper surface of the substrate 10 is first fixed and the substrate 10 is fixed, the reference prism 22 is used to adjust only the angle of the glass plate 12. Only by this, the adhered quadrangular prism 14 bonded to the plurality of glass plates 12 can be cut one after another.

However, the present invention is not limited to the angle adjusting method of the above-described embodiment, and the blade 18 is adjusted so that the reflected light from the reflective film 20 and the reflected light from the reference surface 22a return to the pinhole 34. Rectangular prism 14 to be cut, which is adhered on the verticality of the substrate 10 and the glass plate 12.
The verticality of may be adjusted almost simultaneously.

[0025]

Since the present invention is configured as described above in detail, it has an effect that the quadrangular prism can be cut in a right angle relationship with respect to the longitudinal axis.

[Brief description of drawings]

FIG. 1 is a plan view of a cutting jig used in an embodiment of the present invention.

FIG. 2 is a front view of a cutting jig.

FIG. 3 is a diagram illustrating a conventional cutting method.

FIG. 4 is a perspective view of a polarization beam splitter before cutting and a polarization beam splitter after cutting.

[Explanation of symbols]

 10 substrate 12 glass plate 14 quadrangular prism to be cut 16 dicing saw 18 blade 20 reflective film 22 reference prism 24 laser beam emitting device 32 screen 34 pinhole

Claims (3)

[Claims] 1. A method of cutting a rectangular prism, comprising cutting two rectangular prisms with their slopes bonded together with a dicing saw, wherein a blade (18) surface of the dicing saw (16) is used. A reflecting film (20) is provided on the laser beam emitting means (24) equipped with a screen (32) having a pinhole (34) is fixed to a parallel plate substrate (10), and a square prism prism (14) to be cut is formed. Place the parallel plate glass plate (12) adhered on the substrate (10), the glass plate (12) so that one surface is in contact with the longitudinal surface of the square prism prism (14) to be cut. A reference prism (22) which is a rectangular parallelepiped having an accurate shape is placed on the reflection film of the dicing saw (16) through the pinhole (34) of the laser beam emitting means (24) and the reference prism (22). A laser beam is emitted toward (20), and the reflected light from the reflection film (20) and the front After adjusting the angle of the substrate (10) and the glass plate (12) so that the reflected light of the reference prism (22) returns to the pinhole (34), a predetermined length is obtained by the dicing saw (16). A method of cutting a rectangular prism, comprising cutting the rectangular prism (14) to be cut. 2. The pinhole (3) of the laser beam emitting means (24) before placing the glass plate (12) on the substrate (10).
The laser beam is emitted toward the reflective film (20) of the dicing saw (16) through 4), and the angle of the substrate (10) so that the reflected light of the reflective film (20) returns to the pinhole (34). First, adjustment is performed, and then the glass plate (12) having the square prism prism (14) to be cut adhered is placed on the substrate (10) and the reference prism (22) is placed on the glass plate (12). ) Is mounted and the angle of the glass plate (12) is adjusted so that the reflected light reflected by the reference prism (22) returns to the pinhole (34). How to cut a square prism. 3. The method of cutting a square prism according to claim 1, wherein the angle adjustment is performed while rotating the dicing saw (16).