The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 02, 1993
Filed:
Mar. 30, 1992
Nippon Oil Co., Ltd., Tokyo, JP;
Abstract
The present invention provides a CFRP-made optical cylinder comprising (a) CFRP layers containing a carbon fiber arranged in a direction substantially parallel to the cylinder axial direction and (b) CFRP layers containing a carbon fiber arranged in a direction nearly orthogonal to the cylinder axial direction, in which cylinder the carbon fiber arranged in a direction substantially parallel to the cylinder axial direction has a minus thermal expansion coefficient and the cylinder axial direction has a thermal expansion coefficient of -0.5.times.10.sup.-6 /.degree.C. to 0.5.times.10.sup.-6 /.degree.C. In the present optical cylinder, a sharp image can be maintained without making the correction of the optical axis even when the atmospheric temperature changes largely.