JPH09243892A - Optical element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical lens having a high airtight property by providing plural steps of projection parts along an inner peripheral surface of a lens barrel and integrally engaging an engagement part of an optical lens ranging to plural steps of the projection parts. SOLUTION: Two steps of projection parts 1a are provided in the inside of the cylindrical lens barrel 1 along the inner periphery of the lens barrel 1. The optical lens 2 has the valid radial part 2a of the lens whose central part surface is bent and the engagement part of its periphery. For forming such a optical element, lens nitric material 3 such as glass, plastics, etc., is arranged in the lens barrel 1, and the lens nitric material 3 is heated to a deformable temp. to be pressure molded by a die 4 from upper and lower sides. Thereafter, the lens nitric material 3 deformed to the shape of the optical lens 2 is cooled to the transition temp. of the lens nitric material 3 in the die 4. Plural steps of projection parts 1a of the lens barrel 1 are preferred to be provided spirally along the inner peripheral surface of the lens barrel 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical element used in optical communication equipment and the like.

[0002]

2. Description of the Related Art A conventional optical element is disclosed in Japanese Patent Application No. 6-21116.
As shown in FIG. 1 of No. 8, it is composed of a cylindrical lens barrel and an optical lens incorporated in the lens barrel,
The optical lens sandwiches and engages with a protrusion provided along the inner peripheral surface of the lens barrel.

[0003]

With the diversification of methods of using optical elements, mutual airtightness becomes important in the space inside the lens barrel bordering the optical lens. In such a configuration, there is a problem that mutual airtightness cannot be ensured to a high degree in the space inside the lens barrel that is bounded by the optical lens.

Therefore, the present invention solves such a problem,
It is an object to provide an optical lens having a high degree of airtightness.

[0005]

In order to achieve this object, the present invention provides a plurality of stages of protrusions along the inner peripheral surface of the lens barrel and engages the optical lens over the plurality of stages of the protrusions. The parts are engaged together, thereby achieving the intended purpose.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The invention according to claim 1 of the present invention is an optical lens comprising a lens effective diameter portion and an engaging portion,
A cylindrical lens barrel having the optical lens disposed therein, a plurality of steps of protrusions are provided along the inner peripheral surface of the lens barrel, and an engaging portion of the optical lens is provided in the plurality of protrusions. This is an optical element characterized by being integrally engaged over steps, and has an effect of improving mutual airtightness in a space before and after the optical lens in the lens barrel as a boundary.

According to a second aspect of the present invention, the optical element according to the first aspect is characterized in that a plurality of steps of protrusions provided on the inner peripheral surface of the lens barrel are continuous to form a spiral shape. And has an action of strengthening the engagement between the optical lens and the lens barrel.

The invention according to claim 3 of the present invention is the optical element according to claim 2, characterized in that the spiral protrusion is provided from one end to the other end of the lens barrel. It has the effect of improving the productivity of optical elements.

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a cross-sectional view of an optical element. Reference numeral 1 denotes a lens barrel, which is formed by molding a nickel alloy into a cylindrical shape. Inside, a two-stage protruding portion 1a is provided along the inner circumference of the lens barrel 1. There is. Reference numeral 2 denotes an optical lens, which has an effective diameter portion 2a of the lens having a curved central surface and an engaging portion 2b around the effective diameter portion 2a.
It is composed of

To mold such an optical element, as shown in FIG. 2, a lens glass material 3 such as glass or plastic is arranged in the lens barrel 1, and the lens glass material 3 is heated to a deformable temperature, Pressure molding is performed with a mold 4 from above and below. After that, the lens glass material 3 deformed into the shape of the optical lens 2 is cooled in the mold 4 to the transition point of the lens glass material 3.

The heat-molded lens glass material 3 spreads in the lens barrel 1 by the mold 4 and reaches the inside of the gap between the plurality of protrusions 1a provided on the lens barrel 1. If the lens glass material 3 is cooled in this state, the coefficient of linear thermal expansion of the lens glass material 3 is set to be larger than that of the lens barrel 1. Therefore, as shown in FIG. 3, the optical lens 2 shrinks toward the center thereof as it cools. In the process of doing, the engaging portion 2b of the optical lens 2 clamps the protruding portion 1a of the lens barrel 1.

Further, during the press molding of the lens glass material 3 described above, the deformed lens glass material 3 reaches the surface of the lens barrel 1 and is bonded to the surface of the lens barrel 1 due to the wetting property of the lens barrel 1.
Since it cools and contracts in this state, no gap is created at the boundary between the lens barrel 1 and the optical lens 2, and the airtightness between the optical lens 2 in the lens barrel 1 and the space before and after the boundary is maintained. It is kept.

Further, the optical lens 2 sandwiches the projecting portion 1a of the lens barrel 1 in a plurality of steps, whereby strong engagement is obtained and at the same time, the lens barrel 1 and the optical lens 2 are formed. The distance of the boundary portion becomes longer than that of the conventional one, and the airtightness between the optical lens 2 in the lens barrel 1 and the space before and after the boundary is further enhanced.

Further, as shown in FIG. 4, by providing a plurality of stages of protrusions 1a of the lens barrel 1 in a spiral shape along the inner peripheral surface of the lens barrel 1, the depressions between the adjacent protrusions 1a are continuous. Therefore, when the lens glass material 3 is pressed, the optical lens 2 can be molded while removing the air accumulated in the depression to the outside.
It is possible to prevent a space from being generated in the engaging portion 2b of the optical lens 2 and to make the engagement between the optical lens 2 and the lens barrel 1 stronger.

Further, as shown in FIG. 5, by providing a spiral protrusion 1a from one end side to the other end side of the lens barrel 1 provided in the lens barrel 1, the cylindrical lens barrel 1 can be threaded or the like. The spiral protrusion 1a can be formed only by performing a simple process, and the productivity is improved. Further, since the surface of the spiral protrusion 1a formed by the threading process becomes rough, when the optical element is formed as described above, the anchor is formed at the boundary between the lens barrel 1 and the optical lens 2. The effect is added and a stronger engagement is obtained.

[0016]

As is apparent from the above description, according to the present invention, a plurality of steps are provided along the inner peripheral surface of the lens barrel, and the engaging portions of the optical lens are integrated over the steps. The lens barrel and the optical lens can be more firmly engaged with each other, the independence of the spaces between them can be improved, and a high-performance optical lens can be provided.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of an optical element according to an embodiment of the present invention.

FIG. 2 is a sectional view of the same optical element when molded.

FIG. 3 is a sectional view of the optical element.

FIG. 4 is a sectional view of a lens barrel of an optical element according to another embodiment.

FIG. 5 is a sectional view of an optical element according to still another embodiment.

[Explanation of symbols]

 1 lens barrel 1a protruding portion 2 optical lens 2a lens effective diameter portion 2b engaging portion

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Eiji Tanaka, Eiji Tanaka, Kyoto, Tsubaki-machi, Tanabe-machi, Oumi 55-12, Matsuzumi Nitto Electric Co., Ltd. Sumikojihama 55-12 Matsushita Nitto Electric Co., Ltd.

Claims (3)

[Claims] 1. An optical lens comprising a lens effective diameter portion and an engaging portion, and a cylindrical lens barrel having the optical lens arranged therein, wherein a plurality of stages are provided along an inner peripheral surface of the lens barrel. And an engaging portion of the optical lens is integrally engaged over a plurality of stages of the protruding portion. 2. A plurality of steps of protrusions provided on the inner peripheral surface of the lens barrel are continuous to form a spiral shape.
The optical element described. 3. The optical element according to claim 2, wherein the spiral protrusion is provided from one end to the other end of the lens barrel.