JPH0469762B2 - - Google Patents

Description

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

BACKGROUND ART Conventionally, as a structure for fixing and holding a lens to a lens frame via an adhesive, a structure as shown in FIGS. 1 and 2, for example, has been adopted. That is, the lens holding structure shown in FIG. 1 is such that the lens 1 is dropped into the lens storage part 3 of the lens frame 2, and the lens 1 is placed in the lens holding part 4 that protrudes in the radial direction inside the lens frame 2. By filling the annular gap between the lens 1 and the inner circumferential surface of the lens storage portion 3 in the lens frame 2 with adhesive 5 and hardening the lens 1, the lens 1 can be held in a predetermined position. It is fixedly held in the frame 2. The means for filling the annular gap with the adhesive 5 include, for example,
Means such as injecting through a syringe with a needle at the tip, or filling through a rod-like member with a sharply shaped tip, etc., have been adopted. Further, in FIG. 1, an example is shown in which the adhesive 5 is filled after the lens 1 is stored in the lens storage part 3.
As shown in FIG. 2, a means for applying (adhering) an adhesive 5 to the lens 1 before housing it in the lens frame 2 is also generally used. That is, as shown in FIG. 2, the lens 1 is rotated around the optical axis l, the adhesive 5 is applied to the outer peripheral surface of the lens 1 via the needle-like member 6, and then the lens 1 is attached to the lens frame 2. When the adhesive 5 hardens, the lens 1 is
This is a means for fixing and holding the lens frame 2 to the lens frame 2. 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 peripheral part of the lens was directly fixed and held on the lens frame 2 via the thin layer of adhesive 5, when the adhesive 5 hardened and shrunk, the outer peripheral surface of the lens 1 was attached to the lens frame 2.
It is strongly pulled in the direction of the inner circumferential surface, and therefore,
Distortion (ascus, crack) 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; 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 entered between the lower surface of the lens 1 and the lens holding part 4 and had hardened, the lens 1
Distortion (asperity, crack) occurred in the surface accuracy, and 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.

Purpose of the Invention The present invention was made in view of the above-mentioned problems of the prior art, and its purpose is to prevent contraction of the adhesive due to curing, expansion and contraction of the lens due to changes in the environment in which the lens is used, etc. It is an object of the present invention to provide a lens holding device capable of holding a lens without affecting the optical characteristics of the lens in any case.

Summary of the Invention The present invention has a structure in which both the lens and the lens frame are provided with a jig fitting part for centering the lens and holding and curing adhesive in cooperation with a jig for centering the lens. By doing so, the above object of the present invention is attempted to be achieved.

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 drawings, in FIGS. 3 and 4, the right side of the optical axis l shows the cross section of the adhesive before hardening (uncured), and the left side shows the cross section of the adhesive in the hardened state. It shows a cross section of the later state.

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

The lens 8 is housed in a lens housing section 12 provided in the lens frame 9, and the lens housing section 12
A lens support portion 13 provided perpendicularly to the optical axis l direction.
The setting structure is such that the optical axis direction of the optical axis is determined by contacting the optical axis. The inner diameter of the lens storage portion 12 is appropriately larger than the outer diameter of the lens 8, and the lens 8 is adhesively fixed to the lens frame 9 via a thick adhesive 10. ing.

The outer peripheral edge of the lens 8 and the inner peripheral surface of the lens housing portion 12 in the lens frame 9 are provided with a fitting surface 15 that fits with the operating portion 14 of the lens centering operation jig 11.
16 are formed respectively, and each mating surface 15,1
6 and the operation part 14 of the jig 11 are fitted together to complete the jig 1.
The setting structure is such that by pressing 1, the centering of the lens 8 and the holding and curing of the adhesive 10 can be performed simultaneously. That is, the fitting surface 15 of the lens 8
is formed on an inclined surface so that the centering operation can be performed via the operation part 14 of the centering operation jig 11,
By pressing the jig 11 in the direction of the optical axis l, the lens 8 can be automatically centered. During this centering operation, the adhesive 10 in an uncured state moves onto the jig 11 as shown in the right sectional view.
The adhesive 10 is pressed and held by the operating portion 14 of the lens 8, and is configured so that the adhesive 10 can be pressed and held while the lens 8 is kept centered and cured. The operating portion 14 of the wedge-shaped jig 11 is guided by an inclined fitting surface 16 on the lens frame 9 side, so that the centering of the lens 8 can be performed more reliably. Note that the jig 11 is designed to be removed after the adhesive 10 has hardened, as shown in the left sectional view.

The adhesive 10 may be attached to the entire outer circumference of the lens 8, or may be attached to the outer circumference of the lens 8 by being divided into a plurality of parts. Moreover, the shape of the adhesive 10 after curing is as follows:
It may have any shape as long as it can be deformed in the radial direction, and is not limited to the illustrated shape. Further, the shape of the lens support portion 13 is not limited to a flat surface, and may be, for example, a curved surface. Further, the deformation absorbing portion 17 of the lens 8 is formed in the adhesive 10 by the operating portion 14 of the jig 11.

According to the above configuration, the deformation absorbing portion 17 of the adhesive 10 attached to the outer peripheral surface of the lens 8 can freely deform in the radial direction, so the temperature changes depending on the usage environment, and the lens 8 Even if the adhesive 10 expands or contracts to some extent, it can be absorbed by the deformation of the deformation absorbing part 17. Similarly, even if the adhesive 10 contracts when it hardens, it can be absorbed by the deformation of the deformation absorbing part 17. As a result, optical distortion can be prevented from occurring in the lens 8, and the optical performance of the lens system can always be maintained at its best.

In particular, according to the invention, the lens 8 and the lens frame 9
In addition, jig fitting surfaces 15 and 16 are respectively formed for centering the lens 8 and for holding and curing the adhesive 10 in cooperation with the centering jig 11.
At the same time as the centering operation of the lens 8 is performed, the deformation absorbing portion 17 is held to be formed and hardened via the centering operation jig 11, so that the centering of the lens 8 can be performed reliably. . In addition, even if the lens 8 expands or contracts to some extent depending on the usage environment, it will deform uniformly in a centered state and the deformation will be uniformly absorbed, so the lens 8 will always remain the same even after the adhesive 10 has hardened. maintains a centered state, making it possible to provide a highly accurate lens system.

FIG. 4 shows a second embodiment of the invention. The feature of this embodiment is that the fitting surface 16 of the lens frame 9 with the jig 11 is formed not as an inclined surface but as a vertical surface, and that the lens 8
A barrier section 18 made of a non-adhesive material is interposed between the lower surface 8a and the lens support section 13 of the lens frame 9. Also, on the mirror frame 9 side,
A dovetail groove 19 is formed to strengthen the bonding force with the adhesive 10.
9 can also be applied to the first embodiment or the embodiments described below. Note that the barrier portion 18
Alternatively, silicon or Teflon may be applied, or the lens support portion 13 itself may be made of crystalline resin or the like. 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 10 does not enter between the lower surface 8a of the lens 8 and the lens support portion 13, and it is possible to further prevent optical distortion from occurring in the lens 8, and to reduce the bonding force of the adhesive 10. It can be made stronger. Other functions and effects are the same as those of the first embodiment, so their explanation will be omitted.

Third, fourth and fifth embodiments of the present invention are shown in FIGS. 5, 6 and 7, respectively. Each example is
The third embodiment shown in FIG. Centering operation part 1 of the jig 11 on the 9 side
The fitting surface 16 with the centering operation part 14a is formed into an inclined surface that gradually becomes lower in the outer radial direction, corresponding to the inclined surface of the centering operation part 14a. Further, in the fourth embodiment shown in FIG. 6, the fitting surface 16 of the lens frame 9 with the centering operation part 14a of the jig 11 is formed by slanting the outer peripheral surface of the lens frame 9. In the fifth embodiment shown in FIG. 7, the fitting surface 16 of the lens frame 9 with the centering operation part 14a of the jig 11 is constructed from the outer peripheral surface of the lens frame 9 itself. be. 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.

In each of the embodiments described above, the same functions and effects as in the first embodiment can be achieved.

Effects of the Invention As described above, according to the present invention, the deformation absorbing portion of the adhesive can absorb the deformation of the lens in the radial direction. Stress can be absorbed by this deformation, and the optical properties of the lens can always be maintained in the best condition. In addition, since it is set to hold and cure the adhesive while accurately centering the lens, it is possible to not only accurately center the lens, but also to align the optical axis of the lens with the mirror after the adhesive has hardened. Since alignment with the axis of the frame can always be maintained, a highly accurate lens system can be provided.

[Brief explanation of drawings]

1 and 2 are explanatory diagrams of the prior art, FIG. 3 is a sectional explanatory diagram showing a first embodiment of the device according to the present invention, and FIG. 4 is a second embodiment of the device according to the present invention. The cross-sectional explanatory diagrams, FIGS. 5, 6, and 7, show
FIG. 7 is an explanatory cross-sectional view of main parts showing third, fourth, and fifth embodiments of the present invention, respectively. 8...Lens, 9...Mirror frame, 10...Adhesive,
11... jig for centering operation, 15, 16... jig fitting surface.

Claims (1)

[Scope of Claims] 1. A lens holding device capable of fixedly holding a lens via an adhesive interposed between an outer circumference of the lens and an inner circumferential surface of a lens frame, wherein a lens is attached to the lens and the lens frame. A lens holding device comprising a jig fitting part for centering the lens and holding and curing the adhesive in cooperation with a centering jig. 2. The lens holding device according to claim 1, wherein the jig fitting portion is formed with an inclined surface and/or a vertical surface. 3. Claim 1, wherein the adhesive layer made of the adhesive has a deformation absorbing portion.
The lens holding device according to item 1 or 2. 4. The lens holding device according to claim 1, 2, or 3, wherein the adhesive layer is also filled in a groove for increasing adhesive force. 5. The method according to claim 1, 2, 3, or 4, wherein a non-adhesive member is interposed between the lens and the lens support portion of the lens frame. Lens holding device.