ROTARY POLYHEDRAL MIRROR MADE OF SYNTHETIC RESIN AND PRODUCTION OF ROTARY POLYHEDRAL MIRROR MADE OF SYNTHETIC RESIN

• Main Author: TERAI YUJI
• Format: Patent
• Language: English
• Published: 08.04.1997
• Edition: 6
• Subjects: OPTICAL ELEMENTS, SYSTEMS, OR APPARATUS; OPTICS; PHYSICS

PROBLEM TO BE SOLVED: To provide a rotary polyhedral mirror made of a synthetic resin which is improved in the flatness of reflection surfaces by making the temp. distribution on the reflection surfaces after parting from molds uniform and obviates the occurrence of unequal rotation by high-speed rotation. SOLUTION: The upper surface of a body 51 having flanks 516 which becomes the reflection surfaces is projectingly provided with a placing section 53 which is specified in the size of a height direction nearly to 10% of the plate thickness of the body and to nearly 5mm in the spacing between the external shape line thereof and the external shape line of the body. The placing section 53 is cooled in the state of bringing this section into contact with the surface of the flat plate in a cooling stage. The flanks 516 which are the reflection surfaces are rested in the air without coming into contact with any point in the cooling and, therefore, the temp. fall state to the height direction of the flanks is made uniform and the degree of shrinkage of the resin is made uniform. The flat plate on which the synthetic resin member formed by molding is placed and which cools this member is otherwise projectingly provided with a projection for placement to avert the contact of the flanks which are the reflection surfaces and to make the temp. fall state uniform.