JPH0547082B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an optical lens fixing device for fixing an optical lens to a lens barrel, which is a holding member, using an adhesive.

[Prior Art] A conventional method of fixing an optical lens to a lens barrel using an adhesive is, for example, as shown in Japanese Patent Application Laid-open No. 58-195811. A syringe or a thin rod was used to fill the space between the two with adhesive, which was then allowed to harden to make the two stick together.

[Problems to be Solved by the Invention] However, in the lens fixing means using an adhesive as described above, the filled adhesive may protrude or flow out within the plane of the effective diameter of the lens.
This may cause serious problems in terms of optical performance and appearance. The increase in the number of man-hours for wiping off and cleaning the protruding adhesive and the occurrence of defects in the lenses and lens barrels that occur during this process are also problems that cannot be ignored. In particular, if the lens is made of plastic, the solvent resistance of the plastic is extremely low, so it cannot be cleaned, and if the adhesive oozes out, the entire product, including the lens barrel, will be defective. Shrinkage force due to curing of the adhesive acts in the outer circumferential direction of the lens, which may cause distortion in the lens. In addition, as a means disclosed in the above-mentioned Japanese Patent Application Laid-Open No. 195811, there is an adhesive injection port (see Figure 6 of the same publication) provided on the lens barrel side; Since the injection port is perpendicular to the direction in which the lens is assembled, there are significant design constraints on the components disposed outside the lens barrel, leading to further disadvantages such as poor assembly workability. Added.

The present invention was made in view of the above-mentioned problems, and by skillfully configuring the part for fixing the lens to the lens barrel, the present invention overcomes the drawbacks of the conventional means for fixing the lens using adhesive. The purpose of the present invention is to provide an optical lens fixing device that completely solves the problem.

[Means for Solving the Problems] In the present invention, a plurality of adhesive injection holes are provided in the peripheral edge of the lens outside the plane of the effective diameter, and a plurality of adhesive injection holes are provided parallel to the optical axis. A space such as a groove and/or hole is provided on the abutting surface of the attachment part to directly face the injection hole of the lens to vent air and prevent the adhesive from extruding, and when bonding, form the groove and/or hole between the two. An adhesive is injected and filled into the space through the adhesive injection hole to bond the two together.

[Function] From the injection hole provided on the peripheral edge outside the effective surface of the lens to the groove and/or hole provided on the abutting surface of the barrel attachment part, or between the peripheral edge of the lens and the abutting surface. Adhesive is injected and filled into the formed space.

[Example] Figures 1A, B, and C show an example of the present invention, and are a fixing device for an optical lens. Figure 1A is a front view of the right half of the optical lens, and Figure 1B is a front view of the right half of the optical lens. Figure 1 A above
FIG. 1C is a sectional view taken along the stepped surface of the lens barrel shown in FIG. 1B.

As shown in FIG. 1B, the optical lens 1 in this embodiment has a flange 2 extending from the periphery outside the effective surface thereof, and the flange 2 is located at equal intervals on the periphery of the flange 2. A plurality of adhesive injection holes 3 are bored through the optical axis in parallel with the optical axis.

On the other hand, on the abutment surface 5 of the barrel portion of the lens barrel 4 to which the lens 1 is attached, as shown in FIGS. 1B and 1C,
A circumferential groove 6 is provided so as to face the plurality of adhesive injection holes 3 . Note that the adhesive injection hole 3 is not limited to a circular hole as shown in FIG. 1A, but may be an arcuate hole 3a that is horizontally elongated in the circumferential direction, as shown in FIG. 1D. The circumferential groove 6 on the abutment surface 5 of the lens barrel 4 may also be a partially arcuate groove 6a formed intermittently in the circumferential direction, as shown in FIG. Injected adhesive 7
The structure is not limited to the above example, as long as the injection hole and the groove are connected so that the injection hole and groove can flow properly (see Fig. 1 F) and the air in the injection hole and groove can be discharged. . In addition, the injection holes 3, 3
If the diameter or width of a is A, and the width of the grooves 6, 6a is B, generally, as shown in FIG. 1F,
Although it is normal that B>A, this relationship is not limited to this because of the adhesive strength depending on the type of adhesive 7.

In the optical lens fixing device of this embodiment configured as described above, first, the optical lens 1 is
As shown in FIG. Inject using a similar method. At this time,
If there is the above-mentioned circumferential groove 6, the same circumferential groove 6 and the injection hole 3
The air inside is preferably discharged from the other injection holes, and the adhesive 7 is smoothly filled into the circumferential groove 6 and the injection hole 3, and is reliably prevented from protruding outside the bonded area. Furthermore, even if the circumferential groove 6 is like the circumferential groove 6a described above, by appropriately forming the shape of the injection hole and groove and the type of adhesive, it is possible to reliably prevent the adhesive from extruding as in the case described above. It's easy to do. Furthermore, the distortion of the lens in the outer circumferential direction due to the shrinkage force during the adhesive curing described above is also successfully eliminated.

FIG. 2A is a sectional view of a main part of an optical lens fixing device showing another embodiment of the present invention, showing a state in which the lens is dropped into a lens barrel. The lens 11 in this embodiment has a convex surface to be adhered, and when the lens is dropped into the lens barrel, the peripheral edge outside the effective surface of the lens 11 and the lens barrel 14 As shown in the figure, a ring-shaped cavity 16 having a wedge-shaped cross-section and a ring-like shape when viewed from the front is formed between it and the abutment surface 15 of the barrel attachment part. In this embodiment, this hole 16 is used as it is as the circumferential groove 6 in FIGS. 1B and 1C.

That is, on the peripheral edge outside the effective diameter of the lens 11 whose adhesive surface is a convex surface, there are a plurality of adhesives penetrating in parallel with the optical axis, exactly the same as the adhesive injection hole 3 in the lens 1 shown in FIG. An injection hole 13 is provided. When the lens 11 configured in this manner is dropped toward the stepped abutment surface 15 of the lens barrel 14, a cross-sectional shape is created between the adhesive surface of the lens 11 and the abutment surface 15 of the lens barrel 14 as shown in the figure. A cavity 16 is formed which is wedge-shaped and ring-shaped when viewed from the front. Just like in the case of the lens 1 shown in FIG. 1, adhesive 17 ( 2B), the air in the cavity 16 and the injection hole 13 will be discharged from the other injection holes, so that the air in the cavity 16 will be filled as shown in the diagram B
As shown in FIG. 2, the adhesive 17 is suitably filled and the adhesive 17 is reliably prevented from protruding into the effective surface. In the case of lenses where the adhesive surface is part of a spherical surface, the adhesive injection hole can also be a simple arc, and there is no need to provide a circumferential groove on the abutment surface of the lens barrel barrel, making it extremely easy to adhere. It is possible to prevent the agent from spilling out.

Although the above embodiments have been described with respect to the case where an optical lens is fixed to a lens barrel, it goes without saying that the present invention can also be applied to optical elements other than lenses, such as flat plates and prisms. It goes without saying that the element may be made of glass or plastic.

[Effects of the Invention] As described above, according to the present invention, with an extremely simple structure, it is possible to reliably prevent the adhesive from protruding onto the effective surface of the lens, and to prevent distortion of the lens due to contractile force when the adhesive hardens. It is possible to provide an optical lens fixing device that has many effects, such as eliminating the occurrence of the problem and having good air flowability, making it extremely easy to inject adhesive.

[Brief explanation of drawings]

FIG. 1 shows an optical lens fixing device showing one embodiment of the present invention, in which A is a front view of the right half of the lens, and B is a sectional view showing the lens A above dropped into a lens barrel. , C is a front view showing the right half of the abutment surface of the barrel attachment part of the lens barrel, D is a front view of the upper right half of the lens showing a modified example of the adhesive injection hole, and E is a front view showing the abutment surface of the lens barrel. A front view of the upper right half of the abutting surface showing a modified example of the circumferential groove, F is an enlarged sectional view of the main part of FIG. 1B, and FIG. 2 is an optical lens fixing device showing another embodiment of the present invention. A is a cross-sectional view showing a state in which the lens is dropped into the lens barrel, and B is an enlarged cross-sectional view of a main part showing a state in which the adhesive is filled in the adhesive portion between the lens and the lens barrel. 1, 11... Optical lens, 3, 13... Adhesive injection hole, 4, 14... Lens barrel, 6... Circumferential groove (space), 7, 17... Adhesive, 16... Empty ( space part).

Claims (1)

[Scope of Claims] 1. A lens barrel for fixing an optical lens with an adhesive; an optical lens having an adhesive injection hole penetrating outside the effective surface of the optical lens; holding the optical lens; An adhesive filling space is provided on the abutting surface of the barreled portion of the lens barrel, directly facing the adhesive injection hole, for venting air and preventing adhesive from running out. Optical lens fixing device.