JPS6322566B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a lens holding device, and more particularly to a lens holding device for supporting a lens system consisting of a plurality of glass lenses.

As is well known, when holding a lens system consisting of multiple glass lenses, the conventional method was to drop the lenses into a lens frame made of a metal tube, etc., and then attach a presser ring to the lens frame to secure it. was. Methods for attaching the retaining ring to the lens frame include screwing, pressing with a bayonut, and fixing a ring. Also, without using a presser ring. There was also a method of fixing the lens directly to the mirror frame by caulking it.

However, in the case of the above-mentioned conventional lens system holding method, the lens system is held by the lens frame, so depending on the dimensional accuracy of the inner diameter of the lens frame and the outer diameter of the lens,
It is no exaggeration to say that the optical precision of a lens system is determined, and for this reason, when manufacturing high-precision lenses, we strive to improve the processing accuracy of the lens frame and ensure that the processing accuracy of lens centering is sufficient. It was necessary to take appropriate precautions.

In addition, plastic lenses are highly susceptible to thermal effects, and when they are fixed in a lens frame, they have the disadvantage that expansion and contraction caused by temperature changes can deteriorate the optical properties of the lens system. .

Furthermore, in the lens system assembly process, if the lens is dropped into the lens frame and fixed, a fairly complex automatic assembly mechanism is required to automatically assemble the entire lens system, resulting in The disadvantage was that automatic assembly was difficult.

In view of the above-mentioned points, it is an object of the present invention to provide a plurality of optical lens composite elements each having a support frame integrally molded with resin on the outer periphery of a glass lens, through a mounting hole provided in the support frame and a connecting rod. To provide a lens holding device which is integrated with the following.

Hereinafter, the present invention will be explained based on illustrated embodiments.

FIG. 1 shows a lens holding device showing one embodiment of the present invention. This lens holding device coaxially supports three glass lenses L ₁ to _{L 3} so that their optical axes coincide. The glass lenses L ₁ to _{L 3} are optical glass lenses after polishing, as shown in FIGS. 2A and 2B, taking the lens L ₁ as an example. On the outer periphery of these lenses L ₁ to _{L 3} , lenses L _{1 are attached as shown in FIGS. 3A and B, and lenses L 1} as shown in FIGS.
As shown in FIG. 3B taking the lens _L3 as an example, the support frames 1 to 3 are integrally molded with resin. The support frames 1 to 3 are formed in an annular plate shape around the lenses L ₁ to L ₃ , and their central axes are arranged around the lenses L _{1 to} L 3 .
It is aligned with the optical axis of L ₃ . Also,
Support frames 1 to 3 have three angles equidistant from the center.
Connection rods 1e are protruded from the inner surface of the support frame 1 at equal positions, and mounting through holes 2a to 2c, 3a to the support frames 2 and 3 are formed in the optical axis direction so as to pass through the connection rods 1e.
3c (however, 2b and 2c are not shown) are bored respectively. Support frames 1 to 3 are glass lenses.
Together with L ₁ to _{L 3} , they form an optical lens complex element used in the lens holding device. That is, the third
As shown in Figures A and B, on the inner surface of the support frame 1,
A connecting rod 1e is integrally formed with the support frame 1 and protrudes by resin molding. A thin cylindrical cover part 1f extending from the outer peripheral edge of the support frame 1 is integrally formed by resin molding. The support frame 1 is made to have a larger outer diameter than the other support frames 2 and 3 so that the inner diameter of the cover part 1f is larger than the outer diameter of the other support frames 2 and 3.

Next, the assembly process of the lens holding device will be explained.

As shown in FIG.
b, 2c, the spacer member 8, and the mounting holes 3a, 3b, 3c of the support frame 3 are sequentially inserted, and the tips thereof are caulked via the washer 9.
Each optical lens complex element is integrated.

In this case, instead of the spacer members 7 and 8 (see FIG. 1) in the above embodiment,
As shown by taking lens L ₂ as an example, support frame 2
Spacer protrusions 2d and 2e may be provided integrally with the frame by resin molding. And the same protrusion 2
Attachment holes 2a, 2b, and 2c are bored through the support frame 2 at d and 2e, respectively. In other words, a short cylindrical spacer protrusion 2 is formed integrally with the support frame 2 at the opening edges of the mounting holes 2a, 2b, and 2c.
d and 2e are provided in a protruding manner. In addition, in this case, the length of the spacer protrusions 2e and 2d is halved,
In the first and third optical lens composite elements located at both left and right ends, spacer protrusions having the length of the other half may be provided only on the other side and one side of the support frames 1 and 3.

6A and 6B show another example of an optical lens composite element in which a mounting notch is provided instead of a mounting through hole in the support frame. This optical lens composite element is a glass lens L, and a support frame 11 that is integrally resin-molded on the outer periphery of the glass lens L, and mounting notches 11a to 11 in the optical axis direction are provided at three equal parts of the outer periphery.
c is drilled. This mounting notch 11a-1
1c has a semicircular shape, and the notches 11a to 11
A connecting rod is inserted into c to fix the optical lens complex element. The optical lens composite element of this example has the advantage that even if the supporting frame 11 cannot be made large due to space constraints, the same element can be integrated with other optical lens composite elements. Furthermore, it has been confirmed that even with three-point support using connecting rods, the same mounting accuracy can be obtained as when the connecting rods are inserted into the through-holes for fixation.

FIG. 7 shows a plastic lens that can be used in place of the second optical lens composite element used in the first embodiment. This lens portion _L4 is formed integrally with a support frame 12 provided on the outer periphery of the lens portion L4 by resin molding. Attachment holes 12a to 12c (12b, 12c) are provided at three equal parts of the support frame 12.
(c not shown) are perforated in each case. As the synthetic resin forming the lens portion _L4 and the support frame 12, thermoplastic resins such as polycarbonate, ABS, polyacetal, and PBT, and thermosetting resins such as epoxy and phenol are used.

As described above, according to the present invention, since the glass lens is held without using a lens frame, the lens accuracy depends on the dimensional accuracy of the inner diameter of the lens frame and the outer diameter of the glass lens. The problems of can be solved.

Further, since the assembly of the lens holding device becomes very simple, automation of the assembly work can be promoted.

Further, since the lens system is equipped with a cover, there is no need for a special cover installation process after the lens system is assembled, and the lens system can be provided with a light shielding effect and a dustproof effect.

Furthermore, if the lens support frame and the spacer member or spacer protrusion are made of the same resin material, each member will expand and contract to the same degree in response to temperature changes, which will improve the optical characteristics of the lens system. impact can be minimized.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a lens holding device showing an embodiment of the present invention, and FIGS. 2A and B are a side view and a front view of a glass lens disposed in the lens holding device shown in FIG. 1 above. Figures 3A and 3A and 4A and 4B are cross-sectional views and front views of the optical lens composite element in which a support frame is formed by resin molding on the outer periphery of the glass lens shown in Figures 2A and B above. 5A and 5B are a cross-sectional view and a front view showing another example of the optical lens complex element, and FIGS. 6A and B are a cross-sectional view and a front view showing still another example of the optical lens complex element. , FIG. 7 is a cross-sectional view of a plastic lens that can be used in the lens holding device of the present invention. 1 to 3, 11, 12...support frame, 2a to 2c,
3a to 3c... Mounting through holes, 2d, 2e... Spacer protrusions, 1e... Connecting rods, 7, 8... Spacer members, L, _L1 to _L3 ... Glass lenses.

Claims (1)

[Scope of Claims] 1. A plurality of optical lens composite elements each having a support frame integrally formed on the outer periphery of a glass lens by resin molding, and a support frame of at least one of the optical lens composite elements; A plurality of connecting rods are integrally formed to stand upright in the optical axis direction of the lens, and a through-hole for attachment or a mounting hole provided in the support frame of the other optical lens composite element so that the connecting rods pass through. a notch, a spacer formed separately or integrally with the support frame, which is fitted into the connecting rod so as to be interposed between the support frames; A lens holding device comprising: a cylindrical cover that is erected in the optical axis direction and integrally formed to enclose another optical lens compound element;