JPS60114834A - Reticle and its production - Google Patents

Abstract

PURPOSE:To produce reticles simply and economically by working a pyramid- like regular uneven relief, electroplating the relief surface to form a lens surface and forming many fine recessed parts on the lens to transfer the electroplating surface to an optical element. CONSTITUTION:Nickel is plated on the mechanically worked pyramid-like relief to turn the pyramids to a shape arraying smooth semisperical surfaces regulately. When the arraying pitches of the relief is 20mu or less and an angle formed by the fine lens-like shapes turned from the pyramids by the nickel plating with the bottom is 15 deg. or less, required brightness and focusing are obtained. Since the fine lens group has regularity due to the mechanical working, diffraction phenomenon is generated, an interference color is generated on the reticle and a out-of-focus image is made like a ring. Since the extremely fine recessed parts are formed on the plated surface, coloring due to the diffraction phenomenon and the ring formation can be removed and a particle-less and bright reticle having high focusing property is obtained.

Description

[Detailed description of the invention] Technical field The present invention relates to a focusing plate for a camera and a method for manufacturing the same.

Prior Art Conventionally, the entire metal surface of the focal plate for cameras such as reflex cameras was sand-sanded. ! It was widely used, and acrylic-like transfers were widely used. The focusing plate made by this manufacturing method has a surface w
The shape of the T surface becomes irregular and sharp, which makes it difficult to see.If the diffusivity is improved, it becomes easier to achieve sharp focus with large blur, but the granules on the matte surface become larger and the viewfinder becomes noticeably darker. If you reduce the diffusivity, the viewfinder will become brighter, but the ability to detect blur will decrease. Various improvements have been attempted to overcome this drawback.

For example, JP-A-53-42726 1% JP-A-54-92
No. 232 devised a method in which a speckle pattern was recorded on a sensitive material. This produces a bright reticle with less graininess, but the graininess becomes more noticeable as the aperture becomes smaller.

In order to eliminate this graininess, in Japanese Patent Publication No. 54-83846, a photosensitive resin was applied onto a metal substrate, a fine pattern mask image was exposed and developed, and etched. and form it. Special Public Service 1986-1990
In No. 931, a regular interference pattern of a laser beam was printed on a dry plate.

Perform pleat processing. However, with the etching method, it is extremely difficult to adjust the depth uniformly, and with the laser method, the equipment is extremely large and adjustment control is difficult. F)
The actuality is small.

The focus plate described in Japanese Patent Application Laid-Open No. 57-148728 is as follows.

An image of a regular fine structure pattern is recorded on a photosensitive material that has the property of converting the original intensity distribution into a surface unevenness distribution, the surface of the photosensitive material is made with gold fine unevenness, and this mold is created by electroforming. In this method as well, it is difficult to obtain uniform unevenness over the entire surface of the reticle, and mold manufacturing becomes expensive.

There are various advantages in making the focusing plate surface a collection of lenses. That is, by controlling the arrangement pitch and lens power between each lens, it is easy to control the blur intensity and brightness. Furthermore, since there is no clarinet of diffused light, there is no black dot-like graininess, and there is little darkness even when a small diameter lens is used.

However, this has the disadvantage that a diffraction phenomenon occurs due to the regular arrangement, and interference colors appear on the reticle.

Furthermore, the blurred image does not turn out to be an unnatural ring-like image, and the sand-printed mat eliminates the natural blur that is characteristic of focusing plates. When the finder magnification is 4 to 5 times, the resolution is below the limit of the human eye's resolution. It is possible to reduce the attenuation of the amount of light due to the original diffusion by adjusting the angle lo' formed with the bottom surface of the lens.

However, it is extremely difficult to manufacture molds with uniformly sized and precisely arranged microlenses, and the various patents mentioned above are extremely expensive and provide only approximate lenses.

OBJECTS OF THE INVENTION It is an object of the present invention to provide a reticle and a method for manufacturing the reticle, which do not suffer from the above-mentioned drawbacks and can be manufactured extremely simply and at low cost.

General In order to achieve the above-mentioned object, the reticle according to the present invention is manufactured by processing a pyramid-shaped regular uneven relief, electroplating the pyramid-shaped uneven relief surface, and forming each pyramid by the electroplating. In addition to forming a lens surface, a large number of minute dents are completely formed on the lens.

Transfer the electroplated surface to an optical material.

Example A preferred embodiment of the invention is as follows.

First, a regular uneven relief consisting of a collection of pyramids is formed by a machine. Next, electroplating is applied to the pyramidal surface, and the smoothing power of the plating causes the pyramidal top and ridgeline to be rounded into a lens shape. At the same time, the finely dispersed emulsion dispersed in the nickel electroplating bath adheres to and separates from the uneven relief surface through an electrical process, thereby forming a large number of minute dents on the lens surface.

The focusing plate thus formed does not suffer from the graininess caused by a sandy surface or the darkening of the finder, and eliminates the annular blur due to the coloring caused by the regularly arranged lens surface.

The reticle manufacturing method of the present invention is extremely simple and inexpensive, requiring only simple gland machining and nickel electroplating;
The reproducibility is high and the performance is excellent.

(Other Embodiment) As an embodiment illustrating the present invention, the drawing shows a characteristic 4 in which a light ray 3 is scattered at a large angle α by a reticle 2 having the entire diffuser relief 1 of the turn. This n' is improved to a relatively narrow angle β as shown in FIG. 2, and a focusing plate 70 having a microlens-like relief 6 with low scattering property and good blurring property is produced. An accurate manufacturing method is provided by the present invention.

FIG. 3 shows the first stage of the manufacturing process of the reticle according to the present invention, with a pitch of 20 μm and an angle of 20 μm with respect to the bottom surface.
A perspective view of a regularly machined relief mold 12 made of a combination of a hexagonal pyramid 10 and a pentagonal pyramid 11 is shown.

Relief machining of pyramids can be easily done with a diamond cutting tool using a grinder or the like. With the recent development of high-precision machining machines, if the material to be cut is appropriately selected, it is easy to machine a pyramid using a simple combination of three straight lines as shown in Figure 3.

The accuracy is also extremely high.

By performing nickel plating on the above-mentioned machined pyramidal relief, the pyramid easily becomes a shape in which smooth hemispherical surfaces are regularly arranged.

The shape of the hemisphere in this case can be easily changed by changing the angle it makes with the base of the pyramid.

In this process, the power of the microlens is related to the brightness of the focusing plate when used as a focusing plate, and also controls the focusing ability, and the array pitch is 4 to 4 times the magnification of the camera's 7-in-dah.
There is a mechanism for making the resolution smaller than the eye's resolution under 5x. In order to satisfy all of these conditions, we machined the array pitch and the angle with the bottom of the pyramid to various values, and experimented by changing the nickel plating thickness, electrolytic dye, and bath composition. The array pitch should be 20p or less.

By setting the angle between the pyramid and the bottom when it is shaped like a microlens by nickel plating to be 15° or less, it is possible to obtain the desired brightness and focusability.

However, since the microlens group has regularity due to machining, a diffraction phenomenon occurs, and interference colors appear on the focus plate, v n ,
The blurred image becomes ring-shaped. Even when the pyramids were made of triangular, square, hexagonal and triangular combinations, or pyramids with different arrangement pitches, the performance was insufficient.

According to the present invention, in addition to obtaining the above-mentioned effects of nickel plating, by creating extremely small indentations on the plated surface, coloring and single ring formation due to diffraction phenomenon do not occur,
Bright, grain-free, even when stopped down to a small aperture lens.
@-I learned that it is possible to obtain a focusing plate with good focusing. This n″f: This is shown in FIG. 4 as an explanatory diagram, and a fine concave relief 13 is formed on the focus plate 12.

A first embodiment of the invention for this purpose is to plate the pyramidal reliefs in addition to ethylene oxide or propylene oxide or ethylene oxide propylene oxide adducts as a component of the acidic nickel electroplating bath. This makes it possible to change a part of a machined pattern into an irregular pattern. A mold having this plated relief shape is used to transfer it to a transparent optical plastic to obtain the desired reticle.

The plated relief surface (turn can be used as a transfer mold as it is, and a mold reversed by electroforming can also be used. When transferred to transparent optical plastic, the unevenness will be opposite, but the performance will be the same. Become.

Nickel plating according to this example uses nickel sulfate, nickel chloride, boric acid, and an all-based nickel bath, with an electrolyte pH of
Keep the value between 4.4 and 4.6 and use A/7 as a basic brightener.
Using onic acid powder, add the above-mentioned finely dispersed emulsion according to Japanese Patent Publication No. 46-644, and adjust the bath temperature to 48-52°C.
In this case, the satin effect due to the finely dispersed emulsion is less effective below a certain amount added.

- It was found that even if the plating time was increased, the satin properties remained constant even if the plating time was increased.

(Second Embodiment) According to the 22 embodiments of the present invention, it was learned that the satin effect described above is controlled by the nickel concentration in the nickel plating bath. (West Germany) product name: Velor A30t - Plating solution 1 when used! Approximately 1 i of 2 tar is appropriate.

To increase the satin effect, the nickel concentration is nickel sulfate (including 5 H, 0) and 380 to 4 per plating solution 11.
00 gr, nickel chloride 7I/(including sH, 0) from 35 to
Good effects were obtained by using a high concentration of about 55 g. At this time, when plating with a high electrolytic current density, the boric acid content should be changed to plating solution 17fi, 955-6
(It is possible to achieve a high level of lr, and prevent the precipitation of hollow nickel.

When plating in a plating bath with a low nickel concentration, satin tends to become uneven due to the shape of the object to be plated, uneven electrolytic current distribution at the point of plating failure, and convection due to heat generated by the plating solution.

This example improves the satin effect and uniformity by increasing the plating density! 11 hits.

Next, if the finely divided emulsion that is added to the nickel plating bath produces a fine satin-like effect, and if the decomposition products adhere to the plated surface due to its own decomposition, the nickel will remain on the plated surface until the plating is completed. inhibits electrodeposition.

The disturbed surface has a normal finely dispersed emulsion particle size of 3.
It has a wide area of about 60 to 100p for ~20μ, and is a fatal defect for a precision diffusion plate mold. Cleaning of plating solution and addition of chemicals.

Changing the solution conditions does not eliminate this defect.

(23 Embodiments) According to the 23 embodiments of the present invention, for example, when the required plating film thickness is obtained in one continuous plating for about 15 minutes, IM
The continuous plating time is 3 to 5 minutes, and the plating is repeated 5 to 3 times.
The bare plating surface was activated and washed in several times while applying ultrasonic waves to the bare plated surface between the seven sides. This removed the decomposition products from the sonoplated surface to obtain the required plating thickness. By adding this midway cleaning process, the electrodeposition inhibiting portion of the 1 decomposition product was reduced to such an extent that it did not pose a problem as a focusing plate mold. In this way, plating work with good yield could be carried out in the presence of decomposition products. The reason for this is.

This seems to be because the probability that the decomposition products will adhere to the same site as before is extremely small.

Advantages of the Invention As revealed above, the advantages of the present invention are as follows.

In the reticle of the present invention, a lens having the same dimensions as the pyramid is obtained by plating a minute pyramid that can be easily obtained by machining, and a mold is obtained in which a large number of extremely small concave portions, that is, lenses are formed on the lens surface. I can do it. A focus plate that has this mold transferred onto transparent optical plastic eliminates the moiré phenomenon and annular blur that occurs when lenses of the same size as the tiny pyramids are arranged. In this way, a focusing plate with reproducibility can be obtained easily and inexpensively.

The shape of the pyramid to be machined can be triangular, square, hexagonal, or a combination thereof, and one dimension can be determined arbitrarily. By arbitrarily selecting functions such as the angle of the pyramid, the thickness of the plating film, and the density of the satin-like particles, it is possible to easily produce a focal sheet metal sheet having characteristics suited to the purpose.

A plated pyramidal relief obtained by machining can also be used as a mold, and after plating,
It is also possible to perform tIL casting and use the reversed image as a mold.

It is possible to perform plating with a high yield by fully selecting the composition of the plating bath and the plating method, the W processing of the mold is easy and reliable, the reproducibility is high, and the focus plate can be manufactured at low cost.

[Brief explanation of the drawing]

FIG. 1 is a diagram illustrating a focus plate with an uneven relief shape obtained by known sand printing and the scattering characteristics of light rays. Figure 2 is a diagram showing the scattering characteristics of light rays and a focus plate with a concave-convex relief of microlenses.
A diagram illustrating an example of a machining surface as a process. FIG. 4 is an enlarged explanatory view of the uneven relief of the focusing plate of the present invention. 1.6.12... Diffusion relief 2.7.12... Focal plate 4.5... Scattering characteristics 10.11... Pyramid l3... Fine mouth relief. Patent applicant Olympus Optical Industry Co., Ltd. - Figure 1
Figure 2 Figure 3 2 Procedural amendment (voluntary) 1987! E281J Manabu Shiga, Commissioner of the Patent Office1, Indication of the case, Patent Application No. 2227G1 of 1982, Name of the invention Focus plate and its manufacturing method3, Relationship with the amended person case Patent applicant address Shibuya, Tokyo Ward Hatagaya 2-43-2 Name
(037) Olympus Optical Industry (1) President Shimoyama 4, Agent 6, Detailed explanation of the specification subject to amendment 7, Contents of amendment (1) Page 6 of the specification Correct 1 in the r electrical process written in line 10 to "in an electrolytic process." (2) In the specification, page 7, line 9, page 11, line 11, and page 9, line 5, respectively. (3) Correct "grinding machine, etc." described in page 7, line 16 of the specification to "grinding machine, etc.". (4) Correct the statement "Finely dispersed chemical emulsion" stated on page 10, line 11 of the specification, by adding "in addition to ". (6) Correct "finely dispersed emulsion" stated in page 10, line 14 of the specification to "finely dispersed emulsion." (7) Specification No. "Great luck" written in line 6 of page 11 is corrected to "great luck." (8) Written in line 7 of page 11 of the specification and line 8 of the same page, respectively. Correct r (including 5H20) J to ``(including 6H20) J and a]. (9) Specification 'as l 2 ) 7im Line I ljL
Correct "Finely dispersed emulsion" to "Finely dispersed one emulsion".

Claims (1)

[Claims] A method for manufacturing an 11+ reticle, comprising: processing a pyramid-shaped regular uneven relief surface, electroplating the pyramid-shaped uneven relief surface, and forming each pyramid with a lens surface by the electroplating. At the same time, a large number of microscopic dents are completely formed in the lens,
A method for manufacturing a focusing plate, characterized in that the electroplated surface is transferred onto a vi-gen material. (2) A method for manufacturing a focusing plate, in which a regular pyramid-shaped uneven relief t'' is processed, electroplating is performed on the uneven relief surface, and each pyramid is made into a lens surface by the electroplating, and the lens surface is A method for manufacturing a focusing plate characterized in that a large number of minute depressions are formed, the electroplated surface is transferred to a mold by the electroforming method, and the surface transferred to the mold is transferred to an optical character material. ( 3) The regular pyramid-shaped uneven relief is a pentagonal pyramid. The method according to claim i-1 or 2, which is obtained by mechanical work as a combination of a square pyramid, a pentagonal pyramid, and a hexagonal pyramid. The method according to claim 1 or 3 and 2, wherein the electroplating is carried out using a Nikke A/'#L plating acidic bath containing finely dispersed emulsion. The method according to claim 4, which is carried out in multiple steps through the process. (6) Completely equipped with a large number of regularly arranged lens-like concavities and convexities. Each lens-like concave and convex surface has a large number of 6 rays that are significantly smaller than a lens. 1. A focusing plate characterized by having a direction.