JPH01167805A - Optical parts - Google Patents

Abstract

PURPOSE:To obtain optical parts for necessitating no mount nor painting for interrupting an unnecessary light beam by forming a part for necessitating to interrupt a light beam on the surface of the optical parts to a rough surface. CONSTITUTION:A lens 1 is constituted of an effective surface 2, a flat part 3, an intermediate part 4 provided on an intermediate part and an edge 5. Also, the effective surface 2 is brought to specular working, and the intermediate part 4 is formed to a rough surface. At the time of forming the rough surface, in case of polishing an edge 8 by a grindstone in a conventional decentering process, a deformed grindstone is used instead of a conventional grindstone, and by polishing the surface of the lens of the outside of the effective diameter simultaneously with decentering, the rough surface is formed. As a result, a light beam which has been made incident on the outside of the effective diameter is scattered, therefore, the influence is scarcely exerted on an image forming point, and accordingly, the lens for necessitating no mount nor painting for interrupting an unnecessary light beam can be obtained.

Description

[Detailed Description of the Invention] Industrial Field of Application The present invention is directed to increasing the surface roughness of optical parts such as mirrors, prisms, and lenses in order to cut unnecessary light rays when using optical parts such as mirrors, prisms, and lenses. This relates to an optical component that scatters light rays and eliminates the need for conventional apertures or mounts for cutting light rays.

Conventional technology Optical instruments such as cameras, microscopes, binoculars, and telescopes include
Many optical components such as lenses, mirrors, prisms, etc. are used. The purpose of these optical instruments is mainly 2.
It is to form a dimensional or three-dimensional image. Therefore, if a part of the surface of each optical component is not a mirror surface but a rough surface, the light rays will be scattered there, and as a result, the image will be flared and the contrast will be poor. In order to block unnecessary light rays, that is, light rays that are incident on areas other than the effective parts of optical components, measures are taken such as covering those parts with mechanical parts or coating them with black paint to absorb the light.

On the other hand, recently, conventional optical devices have been replaced with big amplifier devices for optical disks and laser beam printers, which use lasers as light sources, instead of forming two-dimensional images.
Rather, optical instruments with the function of concentrating energy have been developed. The optical systems used in these optical devices aim to focus a point light source emitted from a laser into a single image at a desired position. For example, in the case of a laser beam printer, there is no problem as long as the sensitivity is lower than the sensitivity of the photosensitive material. In laser optical systems that do not handle images, light scattering has become less of an important issue. Furthermore, in recent years, many glass and plastic molded parts have been used in these laser optical systems.In particular, the use of aspherical lenses has significantly reduced the number of optical parts and has made assembly easier. Efforts are being made to simplify the process and reduce costs.

(For example, Yoshitomi Nagaoka et al., "Industrial Materials J, April 1987 issue, P-42~).

Problems to be Solved by the Invention However, in the above-mentioned optical equipment, each optical component, such as a lens, prism, mirror, etc., is fitted into a mount in order to block unnecessary light rays other than the effective diameter. However, since it is necessary to paint with black paint or paint with black paint, there are problems such as complicated assembly and adjustment and high cost.

In view of the above problems, the present invention provides an optical component that does not require a mount or painting to block unnecessary light rays.

Means for Solving the Problems In order to solve the above problems, the optical component of the present invention is constructed such that part or all of the portion of the surface of the optical component that needs to be blocked is made into a rough surface. be.

Effect of the Invention With the above-described configuration, the present invention changes the part of the optical component that needs to block the light rays from a conventional mirror surface to a rough surface, so that even when the light rays are incident, the light rays are scattered.
As a result, the influence of unnecessary light rays on the image can be significantly reduced.

EXAMPLE Hereinafter, an optical component according to an example of the present invention will be described with reference to the drawings. FIG. 1 is a side view of an optical component in an embodiment of the present invention. The surface of the lens 1 is composed of an effective surface 2, a flat portion 3, an intermediate portion 4, and an edge 5. The effective surface 2 is a portion through which light rays actually need to pass, and has a mirror surface. The flat portion 3 is a portion that facilitates holding of the lens. The intermediate portion 4 is an extension of the shape of the effective surface 2. For example, if the effective surface 2 is a spherical surface, the intermediate portion 4 is also a part of the spherical surface. The presence of the intermediate portion 4 prevents the surface precision from deteriorating due to sudden changes in the shape of the peripheral portion of the effective surface 2. If the intermediate portion 4 is in a mirror-like state, the light rays will pass through it, which will have a large effect on the image point. Therefore, by making the intermediate portion 4 a rough surface, the light rays are scattered, and as a result, the image forming point can be hardly affected.

FIG. 2 is a cross-sectional view of a centering device showing one method for manufacturing the optical component of the present invention. The lens 6 is fixed from both sides with bell chucks 7. In the conventional coring process,
The edge portion 8 has been polished using a grindstone, but if a modified grindstone 9 is used in place of the conventional grindstone, the lens surface outside the effective diameter can be polished and made into a rough surface at the same time as the centering process.

FIG. 3 is a perspective view of a mold illustrating a second method for manufacturing the optical component of the present invention. In recent years, lenses have increasingly been made from plastic or glass by molding. The mold 10 is for molding one side of the lens, and includes an effective surface 2, a flat portion 3,
Effective surface forming portion 1 of each mold to form the shape of intermediate portion 4
1, a flat part forming part 12, and an intermediate part forming part 13.

The flat part forming part 12 and the intermediate part forming part 13 have rough surfaces, and by transferring these to the lens surface, the surfaces other than the effective surfaces can be made rough and light can be scattered.

FIG. 4 shows a cross-sectional view of an optical system in which the optical components of the present invention are combined. Each lens 14 and spacer 15 are sequentially dropped into the lens barrel 16 and assembled. Conventionally, when assembling such lenses, spacers have had the role of maintaining the distance between the lenses and at the same time setting the effective diameter of each lens.

Therefore, the spacer and the lens were in contact with each other at the curved surface of the lens, that is, in the case of a spherical lens, at the spherical surface. Therefore, it has been difficult to assemble the lenses so that the optical axes of each lens are not tilted. However, when the optical component of the present invention is applied to a lens,
As shown in FIG. 4, each lens 14 and spacer 15 are
The flat parts of each lens 14 touch each other, and each lens 14
can be kept stable and parallel.

On the other hand, since the lens surface is rough, light rays incident on the outside of the effective diameter are scattered there, so a new aperture is not required. Generally, when a two-dimensional image is formed using a camera or a microscope, such scattered light becomes flare and deteriorates the image quality. However, when the purpose is to concentrate the laser beam to one point, such as the collimating lens and f-theta lens used in laser beam printers, and the collimating lens and objective lens used for optical pickup in optical disk devices, unnecessary rays are Even if it is scattered on the surface of the part, it has almost no effect.

Note that in order to sufficiently scatter light rays as a rough surface, it is desirable that the surface roughness is 0.1 micron or more.

Further, although the embodiment of the present invention is a lens, the lens does not need to have a flat portion. Furthermore, similar rough surfaces can be used not only for lenses but also for other optical components, such as prisms and mirrors, to cut light rays outside the effective diameter.

Effects of the Invention As described above, the present invention has a rough surface on part or all of the portion of the surface of the optical component that needs to block the light rays, thereby scattering the light rays incident outside the effective diameter. The present invention provides an optical component that is easy to assemble and eliminates the need for mounting and painting that are required for optical components to cut out unnecessary light rays. Furthermore, by manufacturing the optical component of the present invention by molding, it is possible to easily form a rough surface and mass-produce optical components at low cost.

[Brief explanation of the drawing]

FIG. 1 is a side view of an optical component in an embodiment of the present invention;
FIG. 2 is a cross-sectional view of a centering device showing the first manufacturing method of the optical component of the present invention, FIG. 3 is a perspective view of a molding die showing the second manufacturing method, and FIG. 4 is a cross-sectional view of the optical component of the present invention. FIG. 2 is a cross-sectional view showing an optical system when used in combination. 1... Lens, 2... Effective surface, 3...
...Flat part, 4...Middle part. Name of agent: Patent attorney Toshio Nakao Haka1 List 2 Diagram

Claims (2)

[Claims] (1) An optical component characterized in that part or all of the portion of the surface of the optical component that needs to block light rays has a rough surface. (2) The optical component according to claim (1), wherein the surface of the optical component has a shape transferred thereto by molding.