Title:
OPTICAL SYSTEM FOR IMAGE FORMATION
Document Type and Number:
Japanese Patent JP3636319
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To provide a very compact and light-weight optical system for image formation in which a clear image is formed and the brightness of the image is scarcely decreased at a wide viewing angle.
SOLUTION: The optical system for image formation is composed of an aperture diaphragm D and an optical system DS for image formation which forms the image of an object by focusing a light beam which passes through the aperture diaphragm D. The optical system DS has at least three faces and a space which is formed by at least three faces and is filled with a first medium of which the refractivity is larger than 1, and being arranged in the order from the diaphragm D to the image of the object, a first face is a refractive face and at the same time an internal reflective face, a second face is a reflective face having a positive power, opposed to the first face, and eccentrically placed or inclined to an optical axis, and a third face is a refractive face closest to the image of the object. At least two of the three faces have a finite radius of curvature, the second face which is opposite to the first medium side is in contact with a medium of the air.
Inventors:
Koichi Takahashi
Application Number:
JP2002026988A
Publication Date:
April 06, 2005
Filing Date:
May 18, 1995
Export Citation:
Assignee:
Olympus Endo Technology America Inc.
International Classes:
G03B13/02; G02B13/08; G02B13/18; G02B17/08; G02B25/00; G02B27/02; G02F1/13; (IPC1-7): G02B17/08; G02B13/08; G02B13/18; G02B25/00; G02B27/02; G02F1/13
Domestic Patent References:
| JP8234137A | ||||
| JP58078116A | ||||
| JP7120676A | ||||
| JP2297516A | ||||
| JP6121256A |
Foreign References:
| US4874214 | ||||
| WO1994024658A1 |
Attorney, Agent or Firm:
Hiroshi Nagisawa
Ryukichi Abe
Hirukawa Masanobu
Norihiko Uchida
Hideo Sugai
Kenji Aoki
Akira Yonezawa
Ryukichi Abe
Hirukawa Masanobu
Norihiko Uchida
Hideo Sugai
Kenji Aoki
Akira Yonezawa