Title:
GLASS, ITS PRODUCTION AND ITS SLOW COOLING METHOD
Document Type and Number:
Japanese Patent JP3435753
Kind Code:
B2
Abstract:
PURPOSE: To improve optical characteristics and productivity by regularly rotationally symmetrically distributing refractive indices in one direction, thereby forming the glass.
CONSTITUTION: The refractive indices are regularly rotationally symmetrically distributed in one direction. More particularly, the refractive indices of a glass member are distributed rotationally symmetrically with the optical axis of a luminous flux as a center when the glass is used as the optical glass member to be used by making the luminous flux incident thereon. Further, residual stresses are rotationally symmetrically distributed by lowering the temp. of the glass while rotating the glass at the time of a slow cooling operation, by which the glass rotationally symmetrically distributed with the refractive indices is obtd. Then, the physical properties of the glass are rotationally symmetrical as well and the glass having the excellent optical characteristics is obtd. The shortening of the time for the slow cooling operation is possible and the productivity is improved.
Inventors:
Kazufumi Ishibashi
Hiroshi Yamamoto
Atsuzo Yamamoto
Hiroshi Yamamoto
Atsuzo Yamamoto
Application Number:
JP25986093A
Publication Date:
August 11, 2003
Filing Date:
October 18, 1993
Export Citation:
Assignee:
NIKON CORPORATION
International Classes:
G02B3/00; C03B25/00; C03B32/00; (IPC1-7): G02B3/00; C03B25/00; C03B32/00
Domestic Patent References:
| JP5688849A | ||||
| JP416589A | ||||
| JP63230532A |