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US4530583A Expired / Lapsed US ⏱️ 0.0 years remaining

Display device for view finder

Assignee: Canon Inc
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Filing: 1983-03-03
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Granted: 1985-07-23
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Expires: 2003-03-03
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Abstract

Abstract A display device in a view finder of a camera includes an illumination light source for illuminating the display portion and an illumination light leading body. The body has a reflecting surface and two permeable surfaces having such a refracting force such that the light emitting portion of the illumination light source is almost conjugate with the position of the pupil while observing the image in the view finder. The apparatus is arranged in such a manner that the illumination light beam is incident upon the one permeable surface of the illumination light leading body and goes out at the other permeable surface so as to illuminate the display portion. Accordingly, the display portion is observed together with the image in the view finder.

Inventors

  • 👤 Yasuyuki Yamada

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-08 08:20
CPC Classifications
G; G03; G03B; G03B17/00; G03B17/18; G03B17/20; G03B13/00; G03B13/02; G03B13/06; G03B13/08

Claims Analysis

Total Claims: 2
Claim 1
Independent Claim 237 words
A display device within a view finder of a camera, comprising: an albada finder optics, having an objective lens and an eyepiece lens, with a semi-trasparent reflective film applied on the side of the objective lens opposite to the eyepiece lens; a display portion provided between said objective lens and the eyepiece lens for making a display within a view finder field of vision; an illumination light source provided outside of an effective light beam of said finder optics; and an illumination light leading body consisting of a prism having a light incident surface, a light emitting surface and a light reflecting surface, said light incident surface being flat and said light emitting surface having a converging refractive force, said illumination light leading body being arranged on the eyepiece lens side of the display portion with said light incident surface being opposed to the illumination light source and said light emitting surface being closely opposed to the display portion, so that the light beam from the illumination light source is incident on the light incident surface, reflected by the light reflecting surface and emitting through the light emitted surface to illuminate the display portion, and the light beam from the display portion is led to the objective lens, reflected by the semi-transparent reflective film and enters the eyepiece lens, said light emitting surface placing the illuminating light source and the pupil position in an optically conjugate relation.
Claim 2
Dependent Claim 237 words
A display device within a view finder of a camera, comprising: an albada finder optics, having an objective lens and an eyepiece lens, with a semi-trasparent reflective film applied on the side of the objective lens opposite to the eyepiece lens; a display portion provided between said objective lens and the eyepiece lens for making a display within a view finder field of vision; an illumination light source provided outside of an effective light beam of said finder optics; and an illumination light leading body consisting of a prism having a light incident surface, a light emitting surface and a light reflecting surface, said light incident surface being flat and said light emitting surface having a converging refractive force, said illumination light leading body being arranged on the eyepiece lens side of the display portion with said light incident surface being opposed to the illumination light source and said light emitting surface being closely opposed to the display portion, so that the light beam from the illumination light source is incident on the light incident surface, reflected by the light reflecting surface and emitting through the light emitted surface to illuminate the display portion, and the light beam from the display portion is led to the objective lens, reflected by the semi-transparent reflective film and enters the eyepiece lens, said light emitting surface placing the illuminating light source and the pupil position in an optically conjugate relation.

References Cited (Backward Citations)

US4217044A Cited
JPS5528088A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1988-07-22 1989-01-21 1989-07-23 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1992-07-22 1993-01-21 1993-07-23 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1996-07-22 1997-01-21 1997-07-23 $7700.00 Window Closed / Lapsed

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