JPH083570B2 - Optical element holding method - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method of holding an optical element for fixing and holding an optical element such as a lens and a prism on a lens frame.

[Prior Art] As the above-mentioned optical element holding device, generally, the constitutions shown in FIG. 4, FIG. 5 a, b and FIG. 6 are known.

In the structure shown in FIG. 4, a housing 4 having a supporting step 3 for the optical element 2 is formed in the lens frame 1, and the optical element 2 is housed in the housing 4 and then the housing is formed thinly. The upper portion of the portion 4 is bent inward, and the bent claw portion 5 is configured to fix and hold the optical element 2. Such a technique is disclosed in Japanese Utility Model Laid-Open No. 58-18211. Further, in the above-mentioned configuration, the filler may be applied to the gap between the inner peripheral surface of the housing portion 4 and the outer peripheral surface of the optical element 2 and caulking may be used together.

In the configuration shown in FIGS. 5A and 5B, after the optical element 2 is housed in the housing portion 4 of the lens frame 1, the optical element 2 can be fixedly held via the press ring 7 with the elastic member 6 interposed. 5a is a space between the inner surface of the housing 4 and the outer surface of the optical element 2, and FIG. The elastic members 6 are interposed between the respective parts. Such a technique is disclosed in JP-A-59-31915.

In the configuration shown in FIG. 6, the optical element 2 is fixedly held by filling the adhesive 8 into the space between the inner peripheral surface of the housing portion 4 and the outer peripheral surface of the optical element 2 in the lens frame 1 and curing it. This technique is disclosed in JP-A-59-
It is disclosed in Japanese Patent No. 135406.

[Problems to be Solved by the Invention] Among the above-mentioned conventional techniques, the structure for fixing the optical element 2 by the crimping means as shown in FIG. 4 and the presser ring 7 as shown in FIGS. In the configuration in which the optical element 2 is fixed by using the optical element 2, when the caulking force amount (fixing force) or the pressing force of the holding ring 7 is large, there is a big problem that the optical element 2 is optically distorted. In this case, for example, in the case of the fixing structure by caulking means, a filler is used as a means for suppressing the optical distortion, but both the epoxy type and the silicon type have a long curing time of 24 hours, and the misalignment occurs within this curing time. Is likely to occur, which requires a centering adjustment work for that purpose, resulting in extremely poor workability. In addition, a long centering time is required.

In addition, the optical element 2 is formed by an adhesive means as shown in FIG.
In the configuration of fixing and holding, the adhesive 8 is easily deteriorated due to the change of environment, and there is a problem that the quality (appearance) of the optical system is significantly deteriorated.

The present invention has been made in view of the above-mentioned problems of the prior art, and it is possible to fix and hold the optical element in the lens frame in a short time without causing misalignment and prevent deterioration of the adhesive. It is an object of the present invention to provide a method of holding an optical element that can maintain the quality (appearance) of an optical system in a good state.

[Means and Actions for Solving Problems] The present invention provides an anaerobic adhesive in a space between an inner peripheral surface of an optical element housing portion of a lens frame and an outer peripheral surface of an optical element housed in the housing portion. It is possible to cure the adhesive for a short period of time and prevent the adhesive from deteriorating by providing a sealing portion for sealing the void with the agent interposed.

[Example] Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

(First Embodiment) FIGS. 1a and 1b show a first embodiment of an optical element holding device 10 for carrying out the method according to the present invention. FIG. FIG. 1B shows an example in which a lens is applied to a prism as the optical element 11.

As shown in the figure, the lens frame 12 is formed with a housing portion 13 for housing the optical element 11 and an optical element supporting step portion 14, and the optical element (the figure illustrates a lens is illustrated in the housing portion 13. 11) are to be stored. When stored, the optical element 11
It is set so as to come into contact with a support step portion 14 formed in a direction orthogonal to the optical axis 1 to perform positioning in the optical axis direction.

An anaerobic adhesive (for example, Loctite 325, 326, 638, etc.) 15 is filled as a filler in the annular space formed between the inner peripheral surface of the housing portion 13 and the outer peripheral surface of the optical element 11. The housing portion 13 that houses the optical element 11 and is filled with the anaerobic adhesive 15 is configured to be hermetically sealed via the hermetically sealing portion 16. The hermetically sealed portion 16 is formed by bending the opening end side of the storage portion 13 formed in a thin shape inward in a direction orthogonal to the optical axis l. The hermetically sealing part 16 is configured to have a function of lightly fixing and holding the optical element 11 to the extent that the optical element 11 is not distorted while the accommodating part 13 is hermetically sealed. The anaerobic adhesive 15 may be added with a plasticizer or filler (filler made of glass fiber, glass powder or the like) for alleviating generation of optical strain due to curing of the adhesive. When the lens frame 12 is made of plastic, the use of a primer for the contact portion of the anaerobic adhesive 15 ensures sufficient curing.

Next, a method for fixing and holding the optical element 11 by the optical element holding device 10 having the above configuration will be described.

First, the optical element 11 including a lens or a prism is used as a lens frame.
Drop it into the storage 13 at 12. Next, the anaerobic adhesive 15 is filled in the space between the inner peripheral surface of the housing portion 13 and the outer peripheral surface of the optical element 11. Next, the opening end side of the thin storage portion 13 is bent inward to seal the storage portion 13 and the optical element 11
Hold lightly. When the anaerobic adhesive 15 is sealed via the bent sealing portion 16, the anaerobic adhesive 15 is cut off from the outside air (air) to start a chemical reaction and is completely cured in a short time. Therefore, the optical element 11 is securely held via the anaerobic adhesive 15 and the sealing portion 16 without causing optical distortion.

Further, according to the above-mentioned embodiment, since the anaerobic adhesive 15 is completely hardened in a short time, the optical element 11 can be securely held without causing the misalignment, and the workability and the quality can be improved. Further, since the hermetically sealing portion 16 only needs to hold the optical element 11 lightly, no optical distortion occurs in the optical element 11.
Further, by interposing the adhesive 15 having the function of a filling material and an adhesive, it is possible to reliably prevent the occurrence of backlash between the hermetically sealed portion 16 and the optical element 11 which occurs when the environment changes, and to seal the hermetically sealed portion 16 Due to the action, the adhesive 15 does not come into direct contact with the outside air (air), and the deterioration of the adhesive 15 can be prevented. As a result, the environment resistance can be improved, and the deterioration of quality can be prevented.

(Second Embodiment) FIGS. 2a and 2b show a second embodiment of the present invention. The feature of this embodiment is that the holding ring 17 is configured as a sealing portion instead of the sealing portion 16 by the caulking means in FIGS. The holding ring 17 is set so as to be screwed into a screw portion 18 engraved on the inner peripheral surface or the outer peripheral surface of the housing portion 13 of the lens frame 12, and the holding ring 17 can seal the housing portion 13 and the optical axis. The device 11 is configured and set so that it can be held lightly. 2a shows that the press ring 17 is screwed onto the inner peripheral surface of the storage portion 13, and FIG. 2b shows that the press ring 17 is screwed onto the outer peripheral surface of the storage portion 13. It is composed. The other structure is similar to that shown in FIG.
The same components will be assigned the same reference numerals and explanations thereof will be omitted.

According to the above configuration, the storage portion 13 can be sealed via the holding ring 17, and thus the anaerobic adhesive 15 having both the functions of the filler and the adhesive can be cured in a short time. The optical element 11 can be held lightly via the holding ring 17. Other functions and effects are the same as those in the first embodiment, and therefore their explanations are omitted.

Third Embodiment FIGS. 3A and 3B show a third embodiment of the optical element holding device 10 for carrying out the method according to the present invention. The feature of this embodiment is that the outer circumference or the inner circumference of the presser ring 17 has three circumferences.
The point is that one or more springs 19 are additionally provided, and on the other hand, a spring receiving portion 20 that engages with the spring 19 is concavely provided on the inner peripheral surface or the outer peripheral surface of the storage portion 13. That is, the press ring 17 is fitted in the optical axis direction and the spring 19 is locked (locked) to the spring receiving portion 20, thereby sealing the storage part 13 through the press ring 17 and holding the optical element 11 lightly. It is configured so that it can. Since other configurations are similar to those shown in FIGS. 2A and 2B, the same components are designated by the same reference numerals and the description thereof will be omitted.

According to the above configuration, there is an advantage that the presser ring 17 can be set in a state where its function can be exerted by a simple operation. The other actions and effects are similar to those of the first embodiment, and therefore the description thereof is omitted.

In the above embodiment, the lens and the prism are shown as the optical element 11, but the present invention is not limited to this, and it is needless to say that the optical element 11 can be applied to a mirror and other optical elements.

[Advantages of the Invention] As described above, according to the present invention, the anaerobic adhesive cut off from the outside air (air) in the hermetically sealed portion is cured in a short time to prevent misalignment of the optical element. The property is extremely improved. Further, since the anaerobic adhesive and the sealing portion can hold the optical element to such an extent that optical distortion does not occur, it is possible to prevent rattling even if a temperature change or the like occurs due to a change in the environment, and the environment resistance is high. Can be improved. Further, since the adhesive does not come into contact with the outside air due to the closed portion, deterioration can be prevented, the appearance is improved, and the quality can be maintained.

[Brief description of drawings]

1A and 1B are front sectional views showing a first embodiment of the device according to the present invention, and FIGS. 2A and 2B are front sectional views showing a second embodiment of the device according to the present invention, and FIG. , b are front sectional views showing a third embodiment of the device according to the present invention, and FIGS. 4, 5 a, b and 6 are front sectional views showing the constitution of the prior art. 11 …… Optical element 12 …… Lens frame 13 …… Storage section 15 …… Anaerobic adhesive 16 …… Sealing section 17 …… Holding ring (sealing section)

Claims (1)

[Claims] 1. An inner peripheral surface of the lens frame and an outer peripheral surface of the optical element while positioning one side of an optical function surface of the optical element in contact with a supporting step portion in the lens frame in the optical axis direction. An anaerobic adhesive is filled in the void formed between the two, and the filled adhesive is sealed together with the supporting step and the inner peripheral surface, and is provided on the other side of the optical function surface of the optical element. A hermetically-sealing portion that holds lightly so as not to cause optical distortion is arranged on the lens frame on the other side of the optical element, and the adhesive is cut off from the outside air to be cured and the cured adhesive is exposed to the outside air by the sealing portion. A method for holding an optical element, which is characterized by cutting.