JPS60222810A - Lens holder - Google Patents

Abstract

PURPOSE:To enable maintenance of the optical characteristic of a lens at high performance by forming the bore of a lens frame to a large diameter in such a way that an adhesive agent layer is freely deformable in the radial direction of the lens and interposing a non-adhesive member in the contact surfaces between the lens frame and the lens. CONSTITUTION:The lens 8 is adhered and fixed to the lens frame 9 via the adhesive agent 10 interposed between the outside periphery of the lens 8 and the inside circumferential peripheral surface of a lens housing part 12. A barrier part 14 having a small coefft. of friction is interposed in the contact surface with the lens 8 in a step part 13 for holding the lens. The adhesive agent 10 is freely deformable in the radial directon according to such constitution and therefore even if the temp. change owing to using environment, the expansion or shrinkage of the lens or the shrinkage of the adhesive agent on curing arises, such change is absorbed. The generation of the optical strain in the lens 8 is thus prevented and the optical characteristic of the lens is maintained at high performance.

Description

TECHNICAL FIELD The present invention relates to a lens holding device, and more particularly to a lens holding device that fixes and holds a lens to a lens frame via an adhesive.

PRIOR ART Conventionally, a structure as shown in FIGS. 1 and 2, for example, has been adopted as a structure for fixing and holding a lens to a mirror frame via an adhesive. That is, the lens holding configuration shown in FIG. 4, and by filling an annular gap between the lens 1 and the inner peripheral surface of the lens storage portion 3 in the lens frame 2 with an adhesive 5 and hardening the lens 1. is fixedly held on the lens frame 2. Examples of means for filling the annular cavity with the adhesive 5 include injecting it through a syringe having a needle at its tip, or filling it through a rod-like member having a sharply shaped tip. It has been adopted. In addition, in FIG. 1, the lens 1 is placed in the lens storage section 3.
Although an example is shown in which the adhesive 5 is filled after the lens 1 is housed in the lens frame 2, as shown in FIG. It is being That is, as shown in FIG. 2, the lens 1 is aligned with the optical axis A.
The needle-shaped member 6 is attached to the outer peripheral surface of the lens 1.
After applying the adhesive 5 through the lens 1, the lens 1 is housed in the lens storage portion 3 of the lens frame 2, and the lens 1 is fixedly held on the lens frame 2 by curing of the adhesive 5. In this lens 1 holding structure, the lens 1 can be fixedly held on the lens frame 2 in exactly the same manner as in FIG. 1.

However, the conventional lens holding structure described above has the following problems and is not satisfactory as a lens holding device.

(1) Since the outer periphery of the lens 1 was directly fixed and held on the lens frame 2 via the adhesive 5, when the adhesive 5 hardens and contracts, the outer periphery of the lens 1 moves toward the inner periphery of the lens frame 2. As a result of the strong pulling, distortions (backslashes, cracks) occurred in the precision of one surface of the lens, and the optical characteristics of the lens 1 were significantly deteriorated.

(2) In the above conventional configuration, the centering of the lens 1 may be adjusted before the adhesive 5 hardens, but even in this case, the gap between the outer circumference of the lens 1 and the inner circumference of the lens frame 2 is small (o ,
oi ~ 0.02), the thickness of the adhesive layer becomes uneven,
As a result, the centering position of the lens 1 was shifted, and the centering of the lens 1 could not be performed accurately after the adhesive 5 had hardened.

(3) Because the adhesive 5 had gotten around and hardened between the lower surface of the lens 1 and the lens holding part 4, the accuracy of the lens 1 surface was distorted (
As a result, the optical characteristics of the lens 1 were significantly deteriorated. That is, when a part of the adhesive 5 wraps around between the lower surface of the lens 1 and the lens holding part 4 and hardens, the lower surface of the lens 1 does not expand or contract with respect to the contraction of the adhesive 5.
The upper surface 1a of the lens 1 expands and contracts, and as a result, stress is generated inside the lens, causing distortions (backslashes and cracks) in the precision of the lens surface.

The present invention was made in view of the problems of the prior art described above, and its purpose is to prevent the optical properties of the lens from being affected in any way even when shrinkage occurs due to curing of the adhesive. An object of the present invention is to provide a lens holding device capable of holding a lens without causing damage to the lens.

SUMMARY OF THE INVENTION The present invention provides a lens frame with a large inner diameter so that an adhesive layer can be deformed in the radial direction of the lens, and a contact surface of the lens frame with the lens or the lens side. The above object of the present invention is achieved by interposing a non-adhesive member on the surface so that the lens and the contact surface do not directly bond to each other.

Embodiments Hereinafter, embodiments of the present invention will be described in detail using the drawings from FIG. 3 onwards. In addition, in the following explanatory diagram, the third
In Figures 5 and 6, the right side of the optical axis ρ shows the cross section of the adhesive before it hardens (uncured), and the left side shows the cross section of the adhesive after it hardens. It shows.

FIG. 3 shows a first embodiment of the lens holding device 7 according to the present invention. Lens holding device 7 as shown in the figure
It is composed of a lens 8 as a held object, a lens frame 9 for holding the lens 8, an adhesive 10 for adhesively fixing the lens 8 to the lens frame 9, and a fixing jig 11.

The lens 8 is housed in a lens accommodating part 12 provided in the lens frame 9, and comes into contact with a lens holding step 13 formed in the lens accommodating part 12 in a direction perpendicular to the optical axis ρ direction, so that its light is The configuration is configured such that axial positioning is performed. The inner diameter of the lens accommodating portion 12 is appropriately larger than the outer diameter of the lens 8 (the outer circumference of the lens 8 and the lens accommodating portion 12
The gap with the inner circumference is 0.02 mm or more, and 0.05
The lens 8 is adhesively fixed to the lens frame 9 via an adhesive 10 interposed between the outer circumferential surface 8a of the lens 8 and the inner circumferential surface of the lens storage portion 12. has been done.

When the adhesive 10 is in an uncured state, as shown in the right sectional view, the adhesive 10 is attached to a fixing jig 11 having an annular or divided structure.
For example, when the fixing jig 11 is removed after the adhesive 10 has hardened,
As shown in the left sectional view, the lens 8 is fixed to the lens frame 9 via an annular adhesive 10, and the lens 8 is attached to the upper part of the lens frame 9.
A lens holding portion 11m is provided to securely hold the outer peripheral edge of the lens.

That is, the lens 8 can be fixedly held at a predetermined position until the uncured adhesive 10 is cured.

The adhesive 10 may be attached to the entire outer periphery of the lens 8, or as shown in FIG. It's okay.

A barrier is provided at the contact portion of the lens frame 9 with the lens 8, that is, the contact portion of the lens holding step portion 13 with the lens 8 to prevent the lens 8 and the lens holding step portion 13 from directly coming into contact with each other. A portion (non-adhesive member) 14 is interposed. As a release agent for the barrier part 14 and the fixing jig 11, for example, a silicone film, a Teflon sheet (non-adhesive sheet),
Liquid materials containing oil components such as glycerin and petrolatum, non-adhesive materials such as crystalline resins such as Teflon powder and nylon,
It uses matter.

According to the above configuration, since the adhesive layer of the adhesive 10 attached to the lens outer circumferential surface 8a can be freely deformed in the radial direction, the temperature changes depending on the usage environment, and the lens 8a
Even if the adhesive layer expands or contracts to some extent, it can be absorbed by the radial deformation of the adhesive layer. Similarly, even if the adhesive 10 shrinks when it hardens, the adhesive layer on the outer circumferential surface 8a of the lens deforms in the radial direction, thereby preventing optical distortion of the lens 8.

In particular, according to the present invention, the barrier portion 14 is provided at the contact portion of the lens holding step 13 with the lens 8, so that the lower surface of the lens 8 and the lens holding step 13 are not directly joined. Therefore, the lens 8 can move freely in the radial direction.

Due to the function of this barrier part 14, even if the temperature changes depending on the usage environment and the lens 8 expands or contracts to some extent, or even if an external force is applied to the lens 8 due to contraction when the adhesive 10 hardens, Since the lens 8 can freely change in the radial direction, stress can be prevented from being generated in the lens 8 in cooperation with the radial deformation of the adhesive layer on the lens outer peripheral surface 8a. As a result, even if the lens 8 itself expands or contracts due to contraction force acting on the adhesive 10 during curing or temperature changes depending on the usage environment, optical distortion will not occur in the lens 8. This allows the optical characteristics of the lens 8 to be maintained in the best condition at all times. Further, according to the above configuration, it is possible to sufficiently secure the holding force of the lens 8 in the optical axis direction and the holding force between the lens 8 and the lens frame 9, and the lens 8 can be stably held.

Further, the gap between the outer circumference of the lens 8 and the lens storage portion 12 is set to at least 0.02 m or more, and the adhesive 10 is applied almost uniformly to the entire circumference of the lens 8 via the fixing jig 11. With this structure, the shrinkage force generated when the adhesive 10 hardens, etc. acts uniformly on the lens 8, and after the lens 8 is fixed at the axial center position via the fixing jig 11, the lens 8 is This allows the optical characteristics of the lens 8 to be maintained in the best condition at all times without causing misalignment.

FIG. 5 shows a second embodiment of the invention. The feature of this embodiment is that the contact portion of the lens holding step portion 13 with the lower surface of the lens 8 is configured to have a semicircular cross section. In addition,
The contact portion of the lens holding step 13 with the lower surface of the lens 8 may have a circular cross-section, a triangular cross-section, a polygonal cross-section, or a surface roughened with grains or the like. good. The rest of the structure is the same as that of the first embodiment, so the same members are given the same reference numerals and their explanations will be omitted.

According to the above configuration, the lower surface of the lens 8 and the lens holding step portion 13
The lens 8 is in contact with the lens 8 in a so-called point contact state, and the degree of freedom of the lens 8 in the radial direction is further increased, and the functions and effects described in the first embodiment can be improved. It is.

FIG. 6 shows a third embodiment of the present invention. The feature of this embodiment is that the layer of adhesive 10 interposed between the lens outer circumferential surface 8a and the inner circumferential surface of the lens housing portion 12 is formed to have a U-shaped cross section, and the deformation absorbing portion 15 is It is at the point that I have set. The rest of the structure is the same as that of the first embodiment, so the same members are given the same reference numerals and the explanation thereof will be omitted.

According to the above configuration, the adhesive layer 10a bonded to the outer peripheral portion of the lens 8 can be more easily deformed in the radial direction, and optical distortion of the lens 8 can be more reliably prevented from occurring. Other functions and effects are the same as those of the first embodiment, so their explanation will be omitted.

As a fourth embodiment of the present invention, although not shown, the lens holding step portion 1 in each of the first to third embodiments described above is
The material No. 3 may be made of a material having a small coefficient of friction, such as Teflon. In addition, a wear-damping sheet (for example, Teflon-based material) may be interposed between the lower surface of the lens 8 and the lens holding step 13. Moreover, in the above configuration,
The lens frame 9 itself may be made of Teflon, or the entire lens frame 9 may be coated with Teflon, or only the lens holding step 13 may be made of Teflon and molded in two colors.

According to the above configuration, in addition to the functions and effects of the first embodiment, the degree of freedom of the lens 8 in the radial direction can be further increased.

Note that in each of the above embodiments, only convex lenses are illustrated, but it goes without saying that the present invention can also be applied to concave lenses. Further, in each embodiment, the lens 8 is centered with the inner diameter of the lens frame 9 as the opposite, but it may also be centered with the outer diameter of the lens frame 9 as the opposite. 14 is the mirror frame 9 in advance
Although it is configured to be applied to the side of the lens 8, it may also be applied to the contact portion of the lens 8 and its outer diameter.

Effects of the Invention As described above, according to the present invention, the degree of freedom of the lens in the radial direction can be increased, so that the internal stress caused by the shrinkage of the adhesive when it hardens and the temperature increase when the lens is used can be reduced by this deformation. The optical properties of the lens can be maintained at high performance.

[Brief explanation of drawings]

1 and 2 are explanatory diagrams of the prior art of the apparatus according to the present invention, FIG. 3 is a cross-sectional explanatory diagram showing the first embodiment of the present invention, and FIG. 4 is an illustration of an example of adhesive adhesion structure. A plan view, FIG. 5 is an explanatory cross-sectional view showing a second embodiment of the present invention, and FIG. 6 is an explanatory cross-sectional view showing a third embodiment of the present invention. 8... Lens 9... Lens frame 10... Adhesive 12... Lens housing section 13... Lens holding step section 14... Non-adhesive member (part of barrier) Fig. 1 Fig. 2 Figure 3 Figure 4 Figure 0 Figure 5 Procedural amendment voluntary writing) October 11, 1980 1, Display of the incident Showa IIJ5! ]Year Patent Application No. 79188/2, Title of Invention Lens Holding Device 3, Relationship with the Amendment Case Patent Applicant Address 2-43-2-4 Hatagaya, Shibuya-ku, Tokyo, Agent 6, Subject of Amendment In the "Detailed Description of the Invention" column and Drawing 7 of the specification, contents of amendment (1) The statement "so that the cross section is in the shape of a cursor" in the third line of page 8 of the specification is deleted. (2) The description '0.02mmJ' on page 10, line 18 of the specification is corrected to '0.05mm.' (3) Figure 5 is corrected as shown in the attached drawing. 8. Attached documents Inventory (1) Revised drawings (1 copy, Figure 5)

Claims (6)

[Claims] (1) In a lens holding device capable of fixing and holding a lens via an adhesive interposed between an outer circumference of the lens and an inner circumferential surface of a lens frame, the inner diameter of the lens frame is controlled by the adhesive layer. The lens is formed to have a large diameter so that it can be freely deformed in the radial direction, and the lens and the contact surface are not directly bonded to the contact surface with the lens in the lens frame or the surface on the lens side. 1. A lens holding device characterized in that a non-adhesive member is interposed between the lens holding device and the lens holding device. (2) The lens holding device according to claim 1, wherein the contact surface of the lens frame that contacts the lens has a semicircular, triangular, or polygonal cross section. (3) The lens holding device according to claim 1, wherein at least the contact surface of the lens frame that contacts the lens is made of a non-adhesive member with a small coefficient of friction. (4) The lens holding device according to claim 1, wherein the non-adhesive member is a non-adhesive sheet. (5) Claim 1 or 4, wherein the non-adhesive member is a non-adhesive friction damping sheet.
Lens holding device as described in section. (6) A patent characterized in that the non-adhesive member is composed of a non-adhesive liquid, powder, or crystalline resin that is painted or coated on the lens-contacting surface of the lens frame. A lens holding device according to claim 1. (Force) Claims 1 and 2, characterized in that the adhesive layer has a gap formed therein so that the lens can be deformed in the radial direction.Claims 3 and 4 , the lens holding device according to item 5 or 6.