JPH11156628A - Optical transmission surface processing method for barlike optical transmission body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase productive and reduce production costs by moving an optical transmission body array and/or a single crystal cutter so as to sequentially bring the respective optical transmission body end parts of the optical transmission body array into contact with the cutting edge of the single crystal cutter having a linear cutting edge, and cutting the optical transmission surfaces of the optical transmission body end parts. SOLUTION: For cutting the optical transmission surface of an optical transmission body end surface to be smooth, preferably RMAX 2 μm or lower, and mirror finished, an optical transmission body array 1 constructed by arraying a plurality of optical transmission bodies fixed by a fixing unit 2 is moved along a moving guide 5 with respect to the linear cutting edge of a single crystal cutter 3 fixed to a cutter fixing part 4. This optical transmission body array 1 is made by exposing the optical transmission body end parts on a resin plate made of a phenol resin, an acrylic resin or the like, or a substrate made of a non ferrous-metal plate such as copper, brass or the like and fixing the same by an adhesive. The single crystal cutter 3 has a structure where a single crystal tip is attached to a shank.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for treating an optical transmission surface of a rod-shaped optical transmission body.

[0002]

2. Description of the Related Art Usually, mirror processing of an optical transmission surface of an optical transmission body such as an optical fiber and a rod-shaped lens is performed after primary processing such as cutting.
A polishing treatment method in which rough polishing to finish polishing is performed while sequentially changing the abrasive grains of the abrasive material from coarse to fine, and a transparent resin is applied to the surface after rough polishing by spraying or dipping and subjected to a hardening treatment. Milling method, in which a diamond cutting blade is attached to a rotating head and cut by a milling method to obtain a mirror finish (Japanese Patent Laid-Open No. 9-152518).
Gazette).

However, in the polishing method, it is necessary to carry out the polishing while changing the abrasive grains of the abrasive material from coarser to finer ones sequentially, and the final stage of polishing to finish the light transmitting surface usable as an optical component. Then, the particle size is 0.5
It is necessary to use abrasive grains of μm or less. In addition, if the abrasive used in the polishing in the previous step remains, the abrasive grains cause scratches on the light transmission surface during processing, and the productivity is significantly reduced. Therefore, it is necessary to completely remove the abrasive in the previous step when making the abrasive grains finer, but as a result, there is a problem that the entire processing steps and equipment become complicated and the productivity is low.

[0004] In the coating method, the surface remaining usable as an optical component can be finished by filling the remaining scratches in the rough polishing with a coating material. At this time, the rough polishing is performed by polishing with abrasive grains having a grain size of about 3 μm. Although the productivity is higher than that of the polishing treatment method, if there is a difference in the refractive index between the light transmitting material and the coating material, light is refracted and scattered at the scratched portion. Also, in the coating process, unevenness of the light transmission surface due to the adhesion of foreign matter to the coating material, unevenness of the light transmission surface before coating and poor adhesion of the coating material due to repelling of the coating material are likely to occur. There is a problem that an optical defect is more likely to occur.

[0005] In the diamond milling method,
Knife marks and undulations are likely to occur on the optical transmission surface, and play of the optical transmission component parts and eccentricity of the rotating shaft are combined, so that the quality of the finished surface is likely to deteriorate. In order to further reduce the number of knife marks, the light transmission surface must be repeatedly cut with a small amount of feed, and the cutting distance becomes several tens to several hundred times the entire length of the light transmission surface, and the wear of the cutting edge is extremely low. In addition, there is a problem that the life of the diamond cutting blade is shortened and the cost is increased.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to provide an optical transmission surface processing method for obtaining a rod-shaped optical transmission body having excellent optical characteristics and a smooth optical transmission surface at high productivity and low production cost. Is to do.

[0007]

SUMMARY OF THE INVENTION The present invention provides an optical transmitter array having a plurality of optical transmitters arrayed with respect to a cutting edge of a single crystal cutting blade having a linear cutting edge. A light transmission surface of a rod-shaped light transmission body, wherein the light transmission surface at the end of the light transmission body is cut by moving the light transmission body array body and / or the single crystal body cutting blade so that the portions come into contact sequentially. ,It is in.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention is preferably applied to a rod-shaped optical transmission member, particularly a plastic rod-shaped optical transmission member. Hereinafter, the present invention will be described in detail with reference to the drawings. FIG. 1 is a perspective view of an example of an apparatus used for processing an optical transmission surface of a rod-shaped optical transmission body according to the present invention. In FIG. 1, 1 is an optical transmission body array body, 2 is an optical transmission body array fixing unit, 3 is a single crystal cutting blade, 4 is a cutting blade fixing section, 5 is an optical transmission body array fixing unit moving guide, 6 Denotes an end mill, 7 denotes an end mill drive motor, and 8 denotes a fixed clamp. FIG. 2 is a perspective view of an example of the optical transmission body array according to the present invention. In FIG. 2, 2
1 is a rod-shaped optical transmission body, 22 is a substrate, and 23 is an adhesive.
FIG. 3 is a perspective view of an example of the single crystal cutting blade according to the present invention. In FIG. 3, 31 is a shank, 32 is a single crystal chip,
33 represents a cutting edge.

In FIG. 1, the end of each light transmitting body in which a plurality of light transmitting bodies are arranged is sequentially arranged with respect to the cutting edge of a single crystal cutting blade 3 having a linear cutting edge fixed by a cutting blade fixing portion 4. By moving the optical transmission body array 1 fixed by the fixing unit 2 in the direction of the cutting blade fixing portion 4 so as to abut, the light transmission surface at the end of the optical transmission body is smooth, preferably R.
_MAX 2 μm or less, and can be cut to a mirror surface. In FIG. 1, the single crystal body cutting blade 3 is fixed, and the optical transmission body array 1 side is moved along the movement guide 5.
The single crystal cutting blade 3 may be moved while the light transmitting body array 1 is fixed, or the light transmitting body array 1 and the single crystal cutting blade 3 may be moved.

[0010] As shown in FIG.
In a state where a plurality of rod-shaped optical transmission bodies 21 are arranged, an end of the optical transmission body is exposed to a substrate 22 such as a resin plate such as phenol resin or acrylic resin or a non-ferrous metal plate such as copper or brass, and an adhesive 23 is formed.
It is fixed by. As shown in FIG. 3, the single crystal cutting blade 3 has a single crystal chip 32 attached to a shank 31, and the cutting blade fixing portion 4 is used to connect the light transmitting body end of the light transmitting body array 1 to the light transmitting body end. Is adjusted. The cutting edge 33 of the single crystal chip 32 is straight.

The single crystal body of the single crystal body cutting blade used in the present invention includes diamond, sapphire, ruby and the like, and since the cutting life varies greatly depending on the hardness thereof, it is particularly preferable to use diamond from the viewpoint of hardness. preferable.

There are two types of diamond, natural and artificial, and both can be used. Since the cutting life of each of these greatly differs depending on the crystal orientation of the blade surface, it is desirable to select an appropriate crystal orientation in order to obtain a stable light transmission surface for a long time. In addition, when obtaining a cutting edge made of natural diamond, if the width of the linear portion of the cutting edge is small, it is easy to obtain an appropriate crystal orientation when cutting, but if the width of the linear portion of the cutting edge is large, Since a large base material itself for processing is required, it becomes difficult to obtain a cutting blade having an appropriate crystal orientation. In addition, natural diamond often includes impurities and scratches in the base material itself, and may adversely affect the finish quality of the light transmission surface,
It is more preferable to use artificial diamond as the single crystal of the single crystal cutting blade of the present invention.

Since the size of a diamond cutting blade increases exponentially as it becomes larger, the width of a blade generally used industrially is 11 mm or less. When one single-crystal diamond cutting blade is used, the width of the light transmission surface that can be processed at one time is not wider than the width of the linear portion of the blade edge,
By arranging a plurality of single-crystal diamond cutting blades in parallel so that the linear portions of the cutting edges overlap, a wide light transmission surface width can be cut at a time.

The cutting of the light transmitting surface at the end of the light transmitting body of the light transmitting body array is performed by sequentially bringing the light transmitting body end of the light transmitting body array into contact with the single crystal cutting blade in accordance with the arrangement order. . The cut amount, that is, the length of the optical transmission body cut by cutting is usually 200 μm or less, preferably 100 μm or less,
More preferably, it is set within a range of 50 μm or less. The smaller the cutting depth, the less the load on the single crystal cutting blade and the longer the cutting life.However, to cut the entire light transmission surface into a mirror surface, the light transmission surface before cutting by the single crystal cutting blade is required. It is preferable to set the cut amount according to the flatness, the parallel movement accuracy of the apparatus moving unit, and the like.

If the optical transmission surface has severe irregularities and warpage,
In the pre-stage of cutting by the single crystal cutting blade, for example, a cutting blade having a linear cutting edge as in the present invention, or a preliminary cutting process using a cutting tool such as a milling cutter or an end mill, and a light transmitting surface in advance. It is desirable to improve the degree of cutting and to reduce the cutting depth during cutting by the single crystal cutting blade as much as possible. The cutting blade in the preliminary cutting process may be either a single crystal or a polycrystal.

According to the above-mentioned method, the light transmission surface of the light transmission body can be cut into a smooth surface, preferably a surface roughness R _{MAX of} 2 μm or less measured according to JIS B0601, and a mirror surface state. An optical transmission surface having substantially the same optical characteristics can be obtained, and the processing steps can be greatly simplified as compared with the polishing method and the coating method. In addition, since the cutting length of the single crystal cutting blade, that is, the relative movement of the cutting blade from the start to the end of cutting is the same as the entire length of the light transmission surface, the wear of the cutting edge is smaller than that of the diamond milling method. , The life of the single crystal diamond cutting blade is extended, and the production cost of the optical transmission component can be significantly reduced. Furthermore, since the relative speed between the single crystal cutting blade and the optical transmission component can be made the same level as that of the diamond milling method, high-speed cutting of the optical transmission surface becomes possible, and the productivity of the optical transmission component is greatly improved. it can.

[0017]

The present invention will be described below in more detail with reference to examples.

(Embodiment 1) A black resin plate was used as a substrate, and a plastic rod-shaped lens was used as an optical transmission body. 2 wt.% Of carbon black was used between the substrate and the rod-shaped lens on an epiform (manufactured by Somar, reactive epoxy adhesive). % Kneaded, and the mixture was cured to prepare an optical transmission element array base plate having a structure in which a number of rod-shaped lenses were arranged in parallel between two substrates. The end of the lens on which the original plate was arranged was exposed and cut into a strip having a width of 5 mm perpendicular to the length direction of the lens.

The apparatus shown in FIG. 1 clamps the cut strip-shaped lens array so that the exposed end face of the lens projects about 0.5 mm from one side of the jig to 4.26 m.
800m between end mills arranged opposite to each other with a gap of m
4.26 mm by passing at a moving speed of m / min
Preliminary cutting was performed to a width and flatness of 20 μm or less. The preliminarily cut lens array is cut with an artificial single crystal diamond having a blade width of 9 mm, which is opposed to a gap of 4.20 mm in width, with straight portions arranged in parallel, and adjusted so as to have a cutting depth of 30 μm on one side. The lens array was cut to a width of 4.20 mm while passing between the blades at a moving speed of 10,000 mm / min. For one lens in the obtained lens array, the surface roughness R _MAX of the light transmission surface and the M
TF (8 line pairs / mm, MTF is Modul
ation Transfer Function, which is generally used as a value representing the resolution of a lens), and the results are shown in Table 1.

(Comparative Example 1) A strip-shaped lens array having a width of 5 mm cut out from the same original plate as in Example 1 was clamped in such a manner that the exposed end face of the lens protruded from the jig by about 0.5 mm to one side, and 4.25 mm. Preliminary cutting to 4.25 mm width and flatness of 20 μm or less by passing in parallel between end mills that are arranged opposite to each other with a gap, and the end surfaces of which are roughened by abrasive treatment using lapping paper The polishing was proceeded while sequentially changing to finer ones, and the polishing in the final stage was finished to a mirror surface of 4.20 mm width with a grain size of 0.3 μm. For one lens in the obtained lens array, the light transmission surface surface roughness R
The _MAX and the optical properties MTF were measured, and the results are shown in Table 1. According to this polishing method, R _MAX and MTF were equivalent to those in Example 1, but the polishing operation required a long time.

(Comparative Example 2) A strip-shaped lens array having a width of 5 mm cut out from the same original plate as in Example 1 was clamped so that the exposed end face of the lens protruded from the jig by about 0.5 mm to one side, and was 4.22 mm. Preliminary cutting to a width of 4.22 mm and a flatness of 20 μm or less is performed by passing in parallel between end mills that are opposed to each other with a gap of.
The surface was roughly polished, and a photopolymerizable transparent resin was sprayed on the surface to apply and photopolymerize and cure. For one lens in the obtained lens array, the light transmission surface surface roughness R _MAX
The optical properties MTF were measured, and the results are shown in Table 1. According to this coating method, R _MAX and MTF were inferior to those according to Example 1.

[0022]

[Table 1]

[0023]

According to the present invention, a light transmitting surface having good optical characteristics can be obtained in a light transmitting body by a greatly simplified processing step. In addition, since the cutting length of the single crystal cutting blade can be made the same as the entire length of the light transmission surface, the wear of the cutting edge is suppressed as compared with the diamond milling method, the life of the single crystal diamond cutting blade is extended, and the The production cost of parts can be significantly reduced. Furthermore, since the relative speed between the single crystal cutting blade and the optical transmission component can be set to the same level as that of the diamond milling method, high-speed cutting of the optical transmission surface becomes possible, and the productivity of the optical transmission component is greatly improved. Can be done.

[Brief description of the drawings]

FIG. 1 is a perspective view of an example of an apparatus used for processing an optical transmission surface of a rod-shaped optical transmission body according to the present invention.

FIG. 2 is a perspective view of an example of an optical transmission body array according to the present invention.

FIG. 3 is a perspective view of an example of a single crystal cutting blade according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Optical transmission body array body 2 Optical transmission body array body fixing unit 3 Single crystal body cutting blade 4 Cutting blade fixing part 5 Optical transmission body array fixing unit moving guide 6 End mill 7 End mill drive motor 8 Fixed clamp 21 Rod-shaped optical transmission body 22 Substrate 23 Adhesive 31 Shank 32 Single crystal chip 33 Cutting edge

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Kazuyoshi Koike 20-1 Miyukicho, Otake City, Hiroshima Prefecture Inside Mitsubishi Rayon Co., Ltd. Otake Works (72) Inventor Nobuhiko Toyota 201-1 Miyukicho, Otake City, Hiroshima Prefecture Mitsubishi Rayon Co., Ltd. Otake Office

Claims (3)

[Claims] 1. An optical transmitter in which a plurality of optical transmitters are arranged so that the ends of the optical transmitters sequentially contact the cutting edge of a single crystal cutting blade having a linear cutting edge. An optical transmission surface treatment method for a rod-shaped optical transmission body, wherein a light transmission surface at an end of the optical transmission body is cut by moving a transmission body array and / or a single crystal body cutting blade. 2. The method according to claim 1, wherein diamond is used as the single crystal body. 3. The optical transmission surface treatment method for a rod-shaped optical transmission body according to claim 1, wherein the optical transmission body array is an optical transmission body array in which an end of the optical transmission body is preliminarily cut.