JP2000072455A - Production of optical element using quartz glass - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely remove clouding by arranging quartz glass between a pair of metal molds, subjecting the quartz glass to thermal forming and cooling a formed optical element down to room temp., then polishing the formed surface by a brush-like abrasive polisher. SOLUTION: A quartz fly-eye lens 4 obtd. by forming a quartz glass material is clouded in its surface and the necessary optical characteristics are not obtainable therewith. The clouding is, thereupon, removed by using a device described below. The quartz fly-eye lens 4 is mounted on a stage 7 and a brush-like abrasive polisher 6 is mounted at an upper shaft 8. The pressure of the polisher 6 on the lens 4 is regulated by a load 11. In addition, the polisher 6 is made movable in a lateral direction by a parallel drive shaft 10. The upper shaft 8 is lowered to press the polisher 6 to the lens 4 by the load of about 150 kg and while abrasives are supplied by a nozzle 12, rotation of about 50 rpm is applied to a lower shaft 9 and the polisher 6 is oscillated by the parallel drive shaft 10, by which the polishing is executed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing an optical element using quartz glass, and more particularly to a method for manufacturing a high-precision optical element by removing fogging on a lens surface after heating and softening a quartz glass material and molding. It is about the method.

[0002]

2. Description of the Related Art Conventionally, as a method of forming optical glass at 800 ° C. or lower, a glass material in a solid state is accommodated in a mold, and the glass material is formed by heating and softening the glass material. A molding method for obtaining a lens without performing grinding, polishing, or the like is known. FIG. 1 shows a state in which a lens is molded by using such a molding method, in which a solid glass material is disposed between a pair of molds.

[0003] In a state where the glass material is heated and softened in a vacuum, a mold is pressed against the glass material, and a plurality of concave portions formed adjacently between flat portions on both surfaces of the mold are formed. It is transferred to a glass material and a lens is formed. However, for quartz glass having a softening temperature of 1300 ° C. or higher, the forming temperature range becomes extremely higher than that for optical glass of 800 ° C. or lower. It was difficult to heat-mold.

[0004]

When quartz glass is actually formed by heating at a temperature exceeding 1300 ° C., when the glass material is softened by heating, the glass component volatilizes from the quartz glass material, and the volatilized glass component becomes a metal mold. The surface of the WC mold material is clouded due to, for example, the WC mold material itself being deteriorated by heating at a high temperature due to the accumulation in the molded concave portion of the molding surface, and as a result, the formed quartz fly-eye lens There is a problem that the surface becomes cloudy and a desired optical surface of the lens cannot be obtained.

The present invention has been made in view of the above problems, and has as its object to provide a method of manufacturing an optical element using quartz glass, which can obtain a desired optical surface.

[0006]

A first means for solving the above-mentioned problems is to arrange quartz glass between a pair of dies, heat-mold the quartz glass, and cool the formed optical element to room temperature. A method of manufacturing an optical element, comprising cooling the molded surface of the optical element with a brush-like polishing polisher after cooling the optical element.

In this means, it is possible to remove the fogging by polishing the surface of the formed optical element with a brush-like polishing polisher. A second means for solving the above-described problem is the first means, wherein the optical element is a quartz fly-eye lens.

In particular, when a fly-eye lens is formed, since a plurality of concave portions are provided in the mold as shown in FIG. 1, the above-mentioned effect of applying the present invention is likely to easily accumulate the volatile glass component. Will be noticeable.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIGS. 20 mm square thickness 1 as shown in FIG.
A quartz glass fly-eye lens 4 as shown in FIG. 2 is manufactured by molding a 7 mm quartz glass material 1 with an upper mold 2 and a lower mold 3.

[0010] The surface of the optically effective surface 5 of the quartz glass flyer lens 4 is clouded, and required optical characteristics are not obtained. Therefore, the fogging is removed using the apparatus shown in FIG. In the apparatus shown in FIG. 4, a quartz flyer lens 4 causing cloudiness is attached to a lens mount 8 attached to a lower shaft 8, and a brush polishing polisher 6 shown in FIG. The load 11 adjusts the pressure of the polisher 6 against the quartz fly-eye lens. The polisher 6 is movable along the parallel drive shaft 10 in the horizontal direction on the paper.
The upper shaft 8 is lowered, and the brush-shaped polishing polisher 6 is pressed against the quartz flyer lens 4 with a load of 150 g. Polishing is performed by oscillating 8. When the optically effective surface 5 of the polished quartz fly-eye lens was inspected, the fogging of the surface was removed and a desired quartz fly-eye lens could be produced.

[0011]

As described above, according to the present invention, the fogging on the surface of an optical element using quartz glass can be surely removed by polishing the surface with a brush-like polishing polisher. Therefore, it is possible to stably supply a high-precision optical element having a functional surface.

[Brief description of the drawings]

FIG. 1 is a schematic view showing a molding method.

FIG. 2 is a schematic view showing a quartz fly-eye lens manufactured in the embodiment.

FIG. 3 is a schematic configuration diagram showing a configuration of a polishing apparatus used in the embodiment.

FIG. 4 is a brush-like polishing polisher used in the embodiment.
FIG.

[Explanation of Signs of Main Parts]

 DESCRIPTION OF SYMBOLS 1 Quartz glass material 2 Upper die 3 Lower die 4 Quartz fly-eye lens 5 Optically effective surface 6 Brush-like polishing polisher 7 Placement stand 8 Upper shaft 9 Lower shaft 10 Parallel drive shaft 11 Load 12 Nozzle

 ──────────────────────────────────────────────────の Continued on the front page (72) Inventor Mitsumasa Negishi 3-2-3 Marunouchi, Chiyoda-ku, Tokyo Nikon Corporation

Claims (2)

[Claims] 1. A quartz glass is placed between a pair of molds, the quartz glass is formed by heating, the formed optical element is cooled to room temperature, and a molding surface of the optical element is brushed with a polishing polisher. A method for manufacturing an optical element, characterized by polishing by a method. 2. The method according to claim 1, wherein the optical element is a quartz fly-eye lens.