JPS62278136A - Production of optical element - Google Patents

Abstract

PURPOSE:To produce a great number of optical elements from a lamellar glass material continuously and at low cost, by heating the lamellar glass material, pressing and premolding the material by a great number of premolds and molding the material by molds under pressure. CONSTITUTION:A plate glass 1 having both ground sides 1a and 1b is heated to a softening temperature by a heater 2. Then, when the plate glass 1 is suspended between a pair of a top and a bottom premolds 3 and 4, the plate glass 1 is pressed by the top mold 3 and the bottom mold 4. Plural mold holes 3a and 4a are opposingly bored in the transfer direction of the plate glass 1 through the premolds 3 and 4 and plural protruded parts are made by press molding. A plate glass 5 having passed the premolding process has optical element corresponding parts approximate to a spherical-surface shape of convex lens by protruded parts 5a and 5b opposingly projected on both the sides of the plate glass. Then, when the plate glass 5 reaches a molding process position, a molding top mold 6 and a molding bottom mold 7 are transferred towards the plate glass 5, each pair of opposing protruded parts 5a and 5b is press molded and a plate glass 8 having functional faces 8a and 8b of a great number of optical elements is molded.

Description

Detailed Description of the Invention 3. Detailed Description of the Invention [Field of Application of the Invention] The present invention relates to a method for manufacturing an optical element, and a method for continuously pressurizing a large number of optical elements by using a plate-shaped molding material. The present invention relates to a manufacturing method that allows molding.

[Background of the invention]

In recent years, various methods have been proposed for manufacturing optical elements such as glass lenses by pressure molding.

An example of such a manufacturing method is JP-A-59-150.
There is a publication No. 728. In this process, a material for molding an optical element (hereinafter referred to as a blank) that has been pre-formed into a shape similar to that of the optical element is held in a mold, and after heating this blank to a temperature that allows it to soften and deform, it is pressed. It is designed to be molded.

By the way, in such a manufacturing method, since the blanks are supplied to the mold one by one, it is necessary to prepare a large number of molds in order to produce optical elements in a single manner.

Furthermore, in order to manufacture optical elements in large quantities, if one blank is used for one optical element, there is a limit to the number of products that can be produced in one manufacturing apparatus, and furthermore, the thermal efficiency is also poor.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for manufacturing an optical element, which eliminates the above-mentioned drawbacks and enables mass production of optical elements at low manufacturing costs.

[Summary of the invention]

The method for manufacturing an optical element of the present invention includes a heating step of heating a plate-shaped glass material, and a pressurizing of the glass material that has undergone the heating step using a preforming mold in which a large number of preforming mold sections are formed to form a large number of optical elements. A preforming process of forming a glass plate having an element-equivalent part; and a preforming process in which the optical element-equivalent part of the glass plate that has gone through the preforming process is pressure-molded using a main mold that provides the functional aspects of the optical element to form a large number of optical elements. This method is characterized by comprising a main molding step of molding a glass plate having.

[Embodiments of the invention]

The method of the present invention will be explained with reference to the drawings.

j1! In Figure 1 and Figure 2, 1 is 1m + 1b on both sides.
The glass plates are each polished and transported in the direction indicated by the arrow in the figure by a transport means (not shown). 2 is a heating device installed on the conveyance path of the glass plate 1;
t-Heating to a temperature that allows softening and deformation. Reference numerals 3 and 4 denote a pair of upper and lower preforming molds, which are also arranged downstream of the heating device 2 in the transport direction of the glass plate 1. The preforming upper mold 3 and the preforming lower mold 4 are each connected to a press cylinder (not shown), and when the glass plate 1 is conveyed and stopped, they move in directions facing each other as shown in FIG. 2 to form the glass plate 1t. - Press. In these preforming upper mold 3 and lower mold 4, a plurality (six in this example) of mold holes 3a and 4m are formed facing each other along the conveyance direction of the glass plate 1, and press Sometimes this mold hole is 3m.

A plus is inserted into 4a to press-form a plurality of convex portions on both the upper and lower surfaces of the glass plate 1 at once. That is, the spherical shape of a convex lens is approximated by the convex portions 5m and 5b protruding from the upper and lower surfaces of the glass plate 5, which have undergone a molding process using the preforming molds 3 and 4 (hereinafter referred to as the preforming process), respectively. A portion corresponding to the optical element is formed. When this preforming process is completed, the upper and lower preforming molds 3 and 4 are moved in the vertical direction, and the glass plate 1 is conveyed through a heating process, and this preforming process is completed. The glass plate 5 that has undergone the process is transported to the next main forming process position described later.At this time, the rear end of the glass plate 5 is cut from the plastic plate 1.

The shape of the convex portion 5a*5h forming the part corresponding to the optical element molded in this preforming step is the shape of the mold hole 3&.

The glass plate 1 can be formed into a desired shape by changing the diameter of the glass plate 1 or by changing the heating temperature of the glass plate 1.

In addition, as a heating device, a resistance heating device such as a Nichrome heater or a Moriprun heater, or an infrared heater,
The heating temperature can be easily controlled by using a high frequency induction heating device or the like.

Next, the main molding process will be explained based on FIG. 3.

6.7 is a pair of upper and lower main molds, and mold surfaces 6m+6b, which provide functional surfaces of optical elements, are formed on opposing surfaces, respectively.
In this embodiment, this mold surface 6 a * for molding a convex lens
6 b e It is molded into a concave shape. The main molding upper mold 6 and the main molding lower mold 7 are each connected to a cylinder device (not shown), and are arranged downstream of the preforming mold 3.4 in the conveying direction of the glass plate 1.

When the glass plate 5 on which the convex portions 5 & 15b have been molded in the portion corresponding to the optical element reaches the main molding step position, the main molding upper mold 6 and the main molding lower mold 7 move toward the glass plate 5, and the glass plate 5 A plastic plate 8 having a large number of functional surfaces 8m and 8b of optical elements is formed by press-molding one pair of convex portions 5m and 5b that face each other vertically.

After completing this main molding process, the glass plate 8 is slowly cooled, and the molded optical element is cut into a desired shape.

FIG. 4 shows an example of the cutting process, in which the optical element 101 is cut from the lath board 8 by thermal shock caused by the laser beam from the radar generator 9. As shown in FIG.

In this example, this cutting step is performed after the slow cooling step, but when the glass plate 8 is still in a high temperature state after the main forming step, the diameter of the V-dice I is reduced. It is also possible to cut into a desired shape using radar light with high energy density.

In addition, although only one set of main molding dies 6 and 7 is placed at the main molding process position, the same number of main molding dies as the number of parts corresponding to optical elements to be molded at one time in the preforming process are arranged. In this case, the convex portion 5a formed on the glass plate 5
Since the entire t 5 b can be fully formed at once, there is no need to cut the rear end of the glass plate 5 that has been preformed from the glass plate 1 .

FIG. 5 shows another embodiment of the preforming process.

In this embodiment, protrusions 3b and 4 are provided on the opposing surfaces of the preforming molds 3 and 40.
b is provided, and these protrusions 3b and 4b form the notches 5c and 5dfe at the same time as forming the protrusions 5m and 5'b in preforming.
Shape. Glass plate 5 that has undergone this preforming process
is actually formed in the same manner as in the above-mentioned embodiment, and the cutout portions 8a,
A glass plate 8 having a diameter of 8d is formed.

In other words, since the strength of these notches 8c and 8d is weak compared to other parts, they can be easily cut by mechanical force after cooling the glass plate 8, and depending on the dimensions of the notches, It has become possible to fold optical elements by hand, and it has become possible to transport optical elements in their plate form as shown in Figure 6, and then fold them when incorporating them into a product, making it possible to store, transport, and incorporate optical elements. Easy to handle.

In each of the above embodiments, the process of heat forming the convex portion having an approximate spherical shape, the process of forming the functional surface of the optical element, and the process of cutting the glass plate having a large number of functional surfaces are separated. By performing these steps in succession, it is possible to efficiently mold a large number of optical elements in a short period of time.

In addition, in each of the above embodiments, a large number of holes in the upper and lower molds are arranged one-dimensionally in the heat molding of the convex portion having an approximate spherical shape, but by changing the diameter of the holes, various types of optical element functions can be achieved. It is now possible to mold convex parts with an approximate spherical shape used for forming surfaces, and it is also possible to continuously form a large number of convex parts with an approximate spherical shape than by arranging holes two-dimensionally. It becomes possible to do so.

〔Effect of the invention〕

As described above, according to the present invention, it is possible to continuously manufacture a large number of optical elements from a plate-shaped glass material.

[Brief explanation of the drawing]

1 to 4 are schematic diagrams of a molding apparatus for carrying out the present invention, FIG. 1 is a schematic side sectional view of a heating device and a preforming mold, and FIG. 2 is a diagram showing its press molding state. FIG. 3 is a schematic side sectional view of the mold, and FIG. 4 is a schematic diagram of the radar oscillation device. FIG. 5 is a schematic side sectional view showing another embodiment of the preforming mold, and FIG. 6 is a side view of a glass plate that has been fully formed through the preforming mold.

Claims (1)

[Claims] A heating step of heating a plate-shaped glass material, and pressurizing the glass material that has undergone the heating step using a preforming mold in which a large number of preforming mold sections are formed to form a glass plate having a large number of optical element corresponding parts. A preforming step, and a main forming step in which a portion of the glass plate that has undergone the preforming step that corresponds to the optical element is pressure-molded using a main mold that provides the functional aspects of the optical element to form a glass plate having a large number of optical elements. A method for manufacturing an optical element, comprising: