Optical element producing device, optical element producing method, controlling program, and recording medium

Patent metadata

Field	Value
Publication number	US-9427919-B2
Application number	US-201213628506-A
Country	US
Kind code	B2
Filing date	Sep 27, 2012
Priority date	Sep 30, 2011
Publication date	Aug 30, 2016
Grant date	Aug 30, 2016

Abstract

When an optical element is produced by sandwiching a resin between a pair of molds, the resin is cured while a mold is kept in contact with the resin until the temperature of the resin reaches a gel point. Throughout the process, a load cell monitors pressure exerted to the mold. After detection of a state in which the pressure exerted to the mold is a negative pressure, the resin is cured while the position of the mold is controlled so that the pressure exerted to the mold is increased to a predetermined positive pressure and thereafter the positive pressure is maintained.

First claim

The invention claimed is:

1. An optical element producing method for shaping a resin by sandwiching the resin between a pair of molds, comprising the steps of:
(1) applying the resin to one of the pair of molds;
(2) causing the other of the pair of molds and the resin to contact with each other and curing the resin until the temperature of the resin reaches a gel point; and
(3) curing the resin, the step (3) including starting, at a time when the temperature of the resin reaches the gel point, control of the position of the one and/or the other of the pair of molds so that pressure exerted from the resin to the other of the pair of molds, which resin is curing and shrinking, is kept at a predetermined pressure;
the pressure exerted from the resin to the other of the pair of molds is monitored throughout the step (2);
at detection of a state in which the pressure exerted to the other of the pair of molds is a negative pressure, the step (2) is switched to the step (3); and
in the step (3), the position of the one and/or the other of the pair of molds is controlled so that the pressure exerted to the other of the pair of molds is increased to a predetermined positive pressure and thereafter the positive pressure maintained.

2. The optical element producing method as set forth in claim 1 , wherein:
the optical element is a composite optical element obtained by forming, on a base which has an optical function, a synthetic resin layer to which a desired optical functional surface has been transferred; and
one of the pair of molds, to which one the resin is applied, serves as the base.

3. The optical element producing method as set forth in claim 1 , wherein step (2) comprises stopping movement of the one and/or the other of the pair of molds at the detection of a minimum detectable positive pressure; and thereafter staring to cure the resin.

Assignees

• Sharp Kk

Inventors

• Nakahashi Takahiro
• Hanato Hiroyuki

Classifications

• B29C2043/5833

  movement of moulds or mould parts, e.g. opening or closing, actuating · CPC title

• B29C2043/5808

  pressure or compressing force · CPC title

• B29C43/58 Primary

  Measuring, controlling or regulating {(for bank adjustment in calendering B29C43/245)} · CPC title

• B29D11/00 Primary

  Producing optical elements, e.g. lenses or prisms (grinding or polishing of optical elements B24B; constructional form of optical elements G02B; {optical parts of spectacles G02C7/00}) · CPC title