JPS6358301A - Preparation of lens - Google Patents

Abstract

PURPOSE:To shorten the time for adhesion and to improve productivity and accuracy by adhering the convex face of a 1st lens and the concave face of the 2nd lens with a photosetting adhesive agent and projecting a luminous flux from a high luminance spot light source uniformly to the lens from the 1st lens side. CONSTITUTION:The convex face of the 1st lens 4 is pressed or imposed to the concave face of the 2nd lens via the photosetting adhesive agent. The luminous flux from the spot light source having the high luminance; for example, short arc type ultra-high-pressure mercury lamp is uniformly distributed by a concave reflection mirror 2 and a plane mirror 6 and is projected to the lens from the 1st lens 4 side to cure the adhesive agent. The time for adhesion is thereby shortened, the leakage of the projection is eliminated and the accuracy is improved.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention achieves achromatization by bonding a convex lens and a concave lens with different refractive index dispersions, which are widely used in telescopes, twin 11m mirrors, camera cameras, etc. Regarding the production of lenses and tablets.

[Prior art and its problems]

Conventionally, two or three laminated lenses called tablets are used to prevent reflections on the lens surface and remove chromatic aberration, and are made by pressing two or three lenses together using an adhesive called balsam. Alternatively, after mounting and aligning the axis, it is left to stand overnight and allowed to slowly and quietly harden and dry, thereby adhering.

However, such an adhesion method takes a long time to manufacture, does not increase productivity, and is also not very workable because the lens being manufactured must be left in a state where it must not be subjected to even the slightest impact for a long time. Furthermore, this also affects the accuracy of the lens.

[Purpose of the invention]

Therefore, the present invention aims to improve productivity and workability by performing the lens bonding process in a short time in the production of achromatic lenses and tablets by bonding convex and concave lenses together, and by irradiating light without leakage. The aim is to create lenses with high precision.

[Structure of the invention and its operation]

In order to achieve this object, the present invention uses a photocurable adhesive as the adhesive and uses a high-intensity point light source as the irradiation light source. Further, with the direction of irradiation of the light beam being vertical, the first lens with a convex adhesive surface is placed on top, and the second lens with a concave adhesive surface is placed on the bottom, so that the lens side of the nail is placed. It is characterized by irradiation with a radially spreading light beam emitted from a light source.

In the case of a generally well-known achromatic lens, the first surface of the first lens is convex and the second surface is convex, and this second surface serves as the adhesive surface. The radially spreading light flux emitted from the high-intensity point light source first reaches the convex surface, which is the first surface of the first lens, and
After being refracted toward the center of the first lens by several surfaces, it passes through the first lens and reaches the bonding surface between the first lens and the second lens. The photocurable adhesive applied to the adhesive surface reacts to the irradiated light, causing a crosslinking/polymerization reaction and hardening and drying in a short time, thereby completing the bonding process in a short time. In reality, it is necessary to align the optical axes of the two lenses, which is called centering, so first, temporary bonding is performed with short-time irradiation, and then the axis alignment of the two lenses is performed, and then long-term irradiation is performed to align the optical axes of the two lenses. Perform gluing. For example, the irradiation intensity of light is 80m
Using a W/cm2 device, the irradiation time for preliminary curing (temporary adhesion) is about 10 seconds at most, and the irradiation time for main adhesion is about 1 minute.

Here, when the light beam reaching the first convex surface of the first lens is parallel light or condensed light, the convex surface refracts the light beam toward the center, so that the adhesive surface at the corner near the outer periphery of the lens is sufficiently illuminated. However, since the present invention is characterized in that it irradiates from the side of the convex surface with a light beam that spreads radially, even if the light beam is refracted toward the center of the first lens by several surfaces, the adhesive surface at the corner Irradiation is ensured without any leakage.

〔Example〕

Embodiments of the present invention will be specifically described below based on the drawings.

Figure J is a schematic explanatory diagram of the basic optical system of the embodiment. A short-arc type ultra-high pressure mercury discharge lamp is most suitable as the high-intensity point light source l. This mercury discharge lamp has a wavelength of 365nr.
Light of a, 405 nm, 436 nm, etc. is emitted and adhesion progresses with these lights. The mirror 2 is a spherical mirror for condensing light, and is provided on the opposite side of the discharge lamp 1 from the first lens 4 and the second lens 5 to be irradiated.
Both are adjusted so that the entire area of the first lens 4 and the second lens 5 is irradiated. In this embodiment, a radially expanding light beam 3 emitted from a discharge lamp 1 illuminates a first lens 4 and a second lens 5 via a plane mirror 6.

FIG. 2 is an explanatory diagram showing the state of light irradiation at the end near the outer periphery of the first and second lenses, where 41 is the first convex surface on the light source side of the first lens, and 42 is the adhesive surface. The second convex surface 7 is a photocurable adhesive.

As mentioned above, the radially expanding light beam X emitted from the light source reaches the first convex surface 41 on the light source side of the first lens, is refracted by the convex surface toward the center of the first lens, and then further The adhesive surface 42 is irradiated while maintaining the radiation state. Therefore, the corner edge 421 near the outer periphery of the lens will not be exposed to radiation leakage, and the entire photocurable adhesive 7 will react to the light and harden and dry.

Although the present invention can be implemented using the embodiments described above, if it is desired to improve the light utilization efficiency, it is preferable to use an integrator lens 8 as shown in FIG.

First, in order to condense the emitted light from the discharge lamp 1 onto the integrator lens 8, an elliptical condensing mirror is provided as the mirror 2. The position of the lamp is adjusted so that the dot is on. The integrator lens 8 is provided at a position that coincides with the second focal point of the condenser mirror 2 . The luminous flux emitted from the discharge lamp 1 becomes a condensed luminous flux 9 by the condenser mirror 2, and after passing through the integrator lens 8, becomes a luminous flux 3 that spreads radially. Irradiation is ensured up to the corner edge 421 near the outer periphery. In this case, the optical axis of the optical system of the irradiation device and the optical axis of the lens to be bonded are arranged so as to coincide or be close to coincide with each other. The illuminance distribution on the bonding surface centered on the optical axis is a symmetrical distribution centered on the optical axis and has good uniformity, allowing for highly accurate bonding.

In this example, the use of the integrator lens 8 increases the utilization efficiency of the luminous flux and improves the illuminance on the bonding surface, so the photocurable adhesive hardens and dries in a shorter time, and the bonding process can be completed in a shorter time. ends at By the way, two lenses, the first lens has a diameter of 50 ma+ and the maximum thickness is 12 mm, and the second lens has a diameter of 50 mm and a center thickness of 3ou++ are pressed together with a light-curing adhesive in between, and the rated When irradiated with an ultra-high pressure mercury discharge lamp with a power consumption of 250 W, the bonding process was completed in 7 seconds for temporary bonding and 58 seconds for main bonding per piece.

The irradiation intensity at this time is approximately 80m when measured at a wavelength of 365nm.
W/cm".

FIG. 4 is an explanatory diagram of another example of a combination of the first and second lenses combined. The figure (a) shows a combination in which the first lens is a biconvex lens and the second lens is a biconcave lens, and the figure (b) shows a combination in which the first lens is a plano-convex lens and the second lens is a biconcave lens. In (c), the first lens is a biconvex lens and the second lens is a meniscus lens. Even in the case of bonding three lenses together, it is possible to manufacture the lens by bonding three lenses at the same time, or by bonding two lenses and then bonding three lenses.

In either combination, the convex surface of the first lens is pressed against or placed on the concave surface of the second lens from above, so the work is stable and safe.

〔Effect of the invention〕

As explained above, by using a light-curing adhesive and using a radially spreading light beam emitted from a high-intensity point light source, the bonding time can be reduced in the process of joining two or three lenses together. can be completed in a short time, improving productivity and work efficiency. Furthermore, since the light beam can be irradiated almost uniformly to the edges of the bonding surface near the outer periphery of the lens, it is possible to manufacture a bone-aligned lens with no omission of irradiation and with higher accuracy.

[Brief explanation of drawings]

Figure 1 is a schematic explanatory diagram of the basic optical system of the embodiment of the present invention,
The second figure is an explanatory diagram showing the irradiation state of the light beam at the end near the outer periphery of the lens, the third figure is a schematic explanatory diagram of an example using an integrator lens, and the fourth figure is an example of other combinations of lenses. FIG. 1 is a short arc type ultra-high pressure mercury discharge lamp, 2 is a mirror,
3 is a radially expanding light beam, 4 is a first lens, 5 is a second lens, 6 is a plane mirror, 7 is a photocurable adhesive, 8 is an integrator lens, 9 is a condensing light beam, 41 is a first lens The first convex surface of the lens, 42, is the second convex surface of the first lens which is the adhesive surface, and 421 is the corner end near the outer periphery of the lens.

Claims (1)

[Claims] A first lens having a convex surface on at least one surface and a second lens having a concave surface on at least one surface are bonded together by bonding the convex surface and the concave surface. In a lens manufacturing method for making a laminated lens, the convex surface of a first lens is pressed or placed on the concave surface of a second lens via a light-curing adhesive, and a high-intensity point light source is inserted from the side of the first lens. A method for manufacturing a lens, comprising the step of bonding a first lens and a second lens by irradiating them with a radially spreading light beam emitted from the lens.