JPH04274201A - Lens array - Google Patents

Abstract

PURPOSE:To provide a lens array formed with plural lens elements arranged in two dimensional configuration which can be manufactured easily with small dispersion in the quality of lens elements. CONSTITUTION:A plurality of half split transparent members 6, each having a shape made by removing part of a cylindrical column up to the rectangular side face parallel to the center line of the cylindrical column, are arranged side by side on a same plane in two sets. A lens array 10 comprises two sets of the divided half transparent members 6 so that the longitudinal direction of said rectangular side face of one set of two may intersect that of the other set at approximately right angles, and these rectangular side faces may come in tight contact with each other.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lens array comprising a two-dimensional plurality of lens elements.

[0002] In response to the increasing number of channels and high functionality of optical circuits in optical communication systems, etc., two or more lens elements are used.
Dimensional lens arrays have come into use. This type of lens array optically combines, for example, an optical semiconductor array formed by two-dimensionally arranging a plurality of optical semiconductor elements, and an optical fiber array formed by two-dimensionally arranging the end faces of a plurality of optical fibers. There is a need for a lens array that is easy to manufacture and has small variations between lens elements.

0003

2. Description of the Related Art Conventionally, as shown in FIG. 6, there has been a microlens array in which a plurality of lens elements 4 are formed by increasing the refractive index of a plurality of locations on a glass substrate 2 using, for example, an ion diffusion method. Are known.

0004

However, the above-mentioned conventional lens array has a problem in that there are large variations in quality between lens elements. Another problem is that large-scale manufacturing equipment such as an ion diffusion device is required, making it difficult to manufacture the lens array.

The present invention was created in view of the above circumstances, and an object of the present invention is to provide a lens array that has small quality variations in lens elements and is easy to manufacture.

[0006]

[Means for Solving the Problems] The lens array of the present invention created to solve the above-mentioned technical problem has a shape in which a cylinder is removed up to a rectangular side surface parallel to its center line, and the rectangular side surface is Two sets of a plurality of semi-split transparent members are arranged in parallel so as to be located on the same plane, and the longitudinal direction of the rectangular side surface in one set is substantially perpendicular to the longitudinal direction of the rectangular side surface in the other set. It is constructed by bringing these rectangular sides into close contact with each other.

[0007]

[Operation] According to the structure of the present invention, a plurality of half-split transparent members arranged in parallel so that their rectangular side surfaces are located on the same plane are divided into two parts.
Since the rectangular side surfaces of one set and the rectangular side faces of the other set are brought into close contact with each other so as to be almost perpendicular to form an integral lens array, the shape of the half-transparent member is uniform for each set. If so, it is possible to provide a lens array with extremely small variations in quality such as focal length. Further, since a large-scale device such as an ion diffusion device is not required during manufacturing, the lens array can be easily manufactured.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Examples of the present invention will be described below with reference to the drawings.

FIG. 1 is a perspective view of a lens array showing an embodiment of the present invention, and FIG. 2 is a perspective view of a half-split transparent member. In this embodiment, eight half-split transparent members 6 (6-1, 2, 3, . . .
, 8) are integrated to form a lens array 10. The half-split transparent member 6 has a shape in which a cylindrical glass block is removed by polishing or the like up to a rectangular side surface 6a parallel to its center line (rotational symmetry axis of the cylinder), and a region near the rectangular side surface 6a on the surface of the cylinder is removed. Two light-shielding films 8 are formed in a strip shape. As the cylindrical glass block serving as the base material of the semi-transparent member 6, a glass rod with a uniform composition can be used, but a glass rod with a refractive index distribution in the radial direction, such as an optical fiber, may also be used. .

The half-transparent members 6-1, 2, 3, and 4 constituting the lower side of the lens array shown in FIG. The half transparent members 6-5, 6, 7, which constitute the upper part of the lens array, are arranged so that the members are in close contact with each other in parallel.
8 is arranged in the same way. The longitudinal direction of the half-transparent members 6-1, 2, 3, and 4 constituting the lower portion is substantially perpendicular to the longitudinal direction of the half-transparent members 6-5, 6, 7, and 8 constituting the upper portion. The rectangular side surfaces 6a are bonded together using an optical adhesive or the like so that the rectangular side surfaces 6a are bonded to each other using an optical adhesive or the like.

According to this configuration, 16
It is possible to provide a lens array in which lens elements are two-dimensionally arranged. If the refractive index or refractive index distribution and shape of each half-transparent member are the same, the focusing action in each lens element will be the same, so that it is possible to provide a lens array with extremely small quality variations between lens elements. Can be done. Further, since the lens array can be constructed by processing such as polishing and integrating the half-transparent members, manufacturing work is easy.

In this embodiment, as explained with reference to FIG. 2, the light-shielding film 8 is formed in the area near the rectangular side surface 6a on the cylindrical surface 6 of the half-split transparent member. This is to minimize crosstalk.

FIG. 3 is an exploded perspective view of a multi-channel light source module constructed using the lens array 10 shown in FIG. 14 is a surface emitting L including a plurality of light emitting parts 12
It is a D array, and the number and arrangement pitch of light emitting parts match the number and pitch of lens elements in the lens array. 18 is a fiber array formed by holding a plurality of optical fibers 16 in parallel, and the number of optical fibers 16 and the arrangement pitch of the optical fiber end faces match the number and arrangement pitch of lens elements in the lens array. When optically coupling the surface emitting LD array 14 and the fiber array 18 having such a configuration, the optical coupling can be easily and reliably achieved by interposing the lens array 10 as shown in FIG. 1 between them. is possible.

Surface emitting LD array 14 and fiber array 1
When building a module by fixing each member with the lens array 10 interposed in a predetermined positional relationship between the lens arrays 10 and 8, a metal frame 20 is placed around the lens array 10 as shown in FIG. It's good to have one. In order to join the lens array 10 made of glass or the like and the metal frame 20, for example, the end surfaces 6b, 6c (
A metal vapor deposition film may be formed in advance in FIG. 2), and this metal vapor deposition film and the inner portion of the metal frame 20 may be soldered. By providing a metal frame around the lens array in this way, when incorporating the lens array into a module, the metal frame can be fixed to the module housing (not shown) by, for example, laser welding, and the lens array can be securely fixed. It becomes possible.

FIG. 5 is a perspective view of a lens array showing another embodiment of the present invention. In this embodiment, the shapes of the half-transparent members 6-1, 2, 3, and 4 that constitute the lower part of the lens array, and the shapes of the half-transparent members 6-9, 10, and 11 that constitute the upper part of the lens array are explained. , 12 have different shapes. That is, by using cylindrical rods with different diameters, or by using cylindrical rods with the same diameter and varying the amount of polishing, a difference is created in the focusing effect between the lower and upper parts of the lens array. be. As a result, each lens element has a function such as converting a circular light beam into an elliptical light beam or an elliptical light beam into a circular light beam, which improves the coupling between optical components with different beam parameters. Be able to do it efficiently. Instead of making the shapes of the half-transparent members different between the upper part and the lower part of the lens array, it is also possible to use half-transparent members of the same shape and have different refractive indexes or refractive index distributions.

In the embodiments described above, the lens array is configured such that the half-transparent member constituting the lower part of the lens array and the half-transparent member constituting the upper part are perpendicular to each other. The half-transparent member constituting the portion and the half-transparent member constituting the upper portion may be inclined at an appropriate angle.

[0017]

[Effects of the Invention] As explained above, according to the present invention,
This has the effect that it is possible to provide a lens array that has small quality variations in lens elements and is easy to manufacture.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a lens array showing an embodiment of the present invention.

FIG. 2 is a perspective view of a semi-transparent member that is a component of the lens array shown in FIG. 1;

FIG. 3 is an exploded perspective view of a multi-channel light source module showing an embodiment of the present invention.

FIG. 4 is a front view showing an example in which the lens array shown in FIG. 1 is provided with a metal frame.

FIG. 5 is a perspective view of a lens array showing another embodiment of the present invention.

FIG. 6 is an explanatory diagram of the prior art.

[Explanation of symbols]

6　Half-split transparent member 10 Lens array

Claims (3)

[Claims] [Claim 1] A plurality of half-split transparent members (6) each having a shape in which the rectangular side surfaces parallel to the center line of the cylinder are removed, and arranged in parallel so that the rectangular side surfaces are located on the same plane.
A lens array comprising two sets of rectangular side surfaces, the rectangular side surfaces of which are brought into close contact with each other such that the longitudinal direction of the rectangular side surfaces of one set and the longitudinal direction of the rectangular side surfaces of the other set are substantially orthogonal. 2. A light shielding film (8) is provided in a region near the rectangular side surface of the cylindrical surface of the half transparent member (6).
2. The lens array according to claim 1, wherein a lens array is formed. 3. The diameter of the semi-transparent member (6) in the one set is different from the diameter of the semi-transparent member (6) in the other set. lens array.