Title:
REAL IMAGE TYPE FINDER SYSTEM
Document Type and Number:
Japanese Patent JP3039171
Kind Code:
B2
Abstract:
PURPOSE: To enable the observation of a good finder image while reducing the size over the entire part of an optical system by utilizing prisms having adequately set roof faces as prisms for an erecting image.
CONSTITUTION: The first prism 6 receives the incidence of the luminous fluxes from an objective lens 1 on the incident face 6a and totally reflects all the incident luminous fluxes at the face 6b toward the face 6c. The face 6c reflects the luminous fluxes from the face 6b and makes the luminous fluxes incident perpendicularly on the face 6d on the same plane as the face 6b, thereby emitting the luminous fluxes to the outside therefrom. The second prism 7 receives the incidence of the luminous fluxes from the face 6d of the first prism 6 on the face 7a, totally reflects the luminous fluxes on the face 7b provided approximately perpendicularly to the optical axis 1a of the objective lens 1 and introduces the luminous fluxes to the face 7d on the same plane as the plane of the face 7a. The luminous fluxes totally reflected by the face 7d are made incident perpendicularly on the face 7e on the same plane as the face 7b and are emitted therefrom to the outside. The finder system is miniaturized by effectively utilizing the total reflection in such a manner and folding the optical paths.
Inventors:
Takeshi Koyama
Akiichi Yamazaki
Akiichi Yamazaki
Application Number:
JP34555292A
Publication Date:
May 08, 2000
Filing Date:
November 30, 1992
Export Citation:
Assignee:
Canon Inc
International Classes:
G03B13/06; (IPC1-7): G03B13/06
Domestic Patent References:
| JP1209432A |
Other References:
【文献】米国特許4673262(US,A)
Attorney, Agent or Firm:
Yukio Takanashi