Dustproof view finder
A dustproof view finder in which an image formed by an objective optical system is made erect by an image erecting optical system and is observed through an ocular optical system as an erect image, the optical system including a pair of front and rear optical elements spaced from one another at a predetermined distance to define an aerial space therebetween, and a seal member which encloses the aerial space.
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Claims
2. A dustproof view finder according to claim 1, further comprising a field frame provided on a surface of one of the optical elements located in the closed aerial space.
3. A dustproof view finder according to claim 1, wherein said enclosing device comprises a seal member which is mounted to the optical elements to enclose the aerial space.
4. A dustproof view finder according to claim 3, wherein said seal member is provided with a fitting portion in which the optical elements are fitted.
5. A dustproof view finder according to claim 4, wherein said seal member has an adhesive surface.
6. A dustproof view finder according to claim 5, wherein said seal member is made of an adhesive material.
7. A dustproof view finder according to claim 5, wherein said seal member is made of an adhesive tape.
9. A dustproof view finder according to claim 8, wherein one of the optical elements is a field plate which is provided thereon with said field frame.
10. A dustproof view finder according to claim 9, wherein said seal member surrounds the other optical element and said field plate.
11. A dustproof view finder according to claim 10, wherein said seal member has an adhesive surface.
12. A dustproof view finder according to claim 11, wherein said seal member is made of an adhesive material.
13. A dustproof view finder according to claim 8, wherein said seal member is made of an adhesive tape.
14. A dustproof view finder according to claim 10, wherein said seal member is provided with mounting portions to which the other optical element and said field plate are mounted.
15. A dustproof view finder according to claim 8, wherein the space defined between the optical elements defines therein an image forming position at which an object image is formed by the objective optical system.
16. A dustproof view finder according to claim 8, further comprising a field frame provided on a surface of one of the optical elements located in the closed aerial space.
3915552 | October 1975 | Rickert |
4119985 | October 10, 1978 | Ando et al. |
4209247 | June 24, 1980 | Urano et al. |
4294529 | October 13, 1981 | Sato et al. |
4381892 | May 3, 1983 | Someya |
4452522 | June 5, 1984 | Murakami et al. |
4705374 | November 10, 1987 | Robings |
4969723 | November 13, 1990 | Kato et al. |
1844211 | December 1961 | DEX |
3213457 | October 1983 | DEX |
3624821 | February 1988 | DEX |
489125 | July 1938 | GBX |
784014 | October 1957 | GBX |
924757 | May 1963 | GBX |
1035990 | July 1966 | GBX |
1052168 | December 1966 | GBX |
1341140 | December 1973 | GBX |
- United Kingdom Search Report, dated Mar. 18, 1992. English Translation of German Office Action, dated Jan. 26, 1993.
Type: Grant
Filed: Oct 3, 1995
Date of Patent: Dec 29, 1998
Assignee: Asahi Kogaku Kogyo Kabushiki Kaisha (Tokyo)
Inventors: Tetsuya Abe (Hokkaido), Katsuhiko Nozaki (Tokyo)
Primary Examiner: Safet Metjahic
Assistant Examiner: Nicholas J. Tuccillo
Law Firm: Geenblum & Bernstein P.L.C.
Application Number: 8/538,619
International Classification: G03B 1302;