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US4448506A Expired / Lapsed US ⏱️ 0.0 years remaining

Exposure control device of a camera

Assignee: Nikon Corp
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Filing: 1982-07-07
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Granted: 1984-05-15
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Expires: 2002-07-07
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Abstract

Abstract An exposure control device of a camera comprises first metering means for effecting metering while dividing an object into a plurality of metering areas and for generating a first metering output determining the exposure of the entire object on the basis of a plurality of photoelectric outputs corresponding to said areas, second metering means for generating a second metering output corresponding to the object light passed through the aperture of a phototaking lens, first operational means for generating a first operation output including information on the difference between the first metering output and the second metering output, second operational means for synthesizing the second metering output during the stop-down of said aperture and the first operation output and generating a second operation output, and blocking means for blocking the stop-down when the second operation output and an output corresponding to a preset shutter speed assume a predetermined relation.

Inventors

  • 👤 Takashi Saegusa
  • 👤 Osamu Maida
  • 👤 Toru Fukuhara

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-28 08:40
CPC Classifications
G; G03; G03B; G03B7/00; G03B7/08; G03B7/099; G03B7/0993; G03B7/0997; G03B7/09979; G03B7/091; G03B7/097; G03B7/09971; G03B7/09974; G03B7/09976

Claims Analysis

Total Claims: 27
Claim 1
Independent Claim 161 words
An exposure control device of a camera having aperture control means for varying an aperture of a phototaking lens, said device comprising: first metering means for effecting metering while dividing an object into a plurality of metering areas and for generating a first metering output determining an exposure of the object on the basis of a plurality of photoelectric outputs corresponding to said areas; second metering means for metering said object through said aperture to generate a second metering output; first operational means for generating a first operation output including information on the difference between said first metering output and said second metering output; second operational means for adding said second metering output during operation of said aperture control means and said first operation output and generating a second operation output; and blocking means for blocking said operation of said aperture control means when said second operation output and an output corresponding to a preset shutter speed assume a predetermined relation.
Claim 2
Dependent Claim 161 words
An exposure control device of a camera having aperture control means for varying an aperture of a phototaking lens, said device comprising: first metering means for effecting metering while dividing an object into a plurality of metering areas and for generating a first metering output determining an exposure of the object on the basis of a plurality of photoelectric outputs corresponding to said areas; second metering means for metering said object through said aperture to generate a second metering output; first operational means for generating a first operation output including information on the difference between said first metering output and said second metering output; second operational means for adding said second metering output during operation of said aperture control means and said first operation output and generating a second operation output; and blocking means for blocking said operation of said aperture control means when said second operation output and an output corresponding to a preset shutter speed assume a predetermined relation.
Claim 3
Dependent Claim 72 words
The device according to claim 1, wherein said camera includes finder optical means having a focus plate, and wherein said first metering means includes a plurality of photoelectric converting means provided so as to be capable of receiving a light passed through the focus plate and means for processing the outputs of said plurality of photoelectric converting means, and said second metering means includes at least one of said photoelectric converting means.
Claim 4
Dependent Claim 90 words
The device according to claim 1, wherein said camera includes finder optical means having a focus plate and wherein said first metering means includes a plurality of photoelectric converting means provided so as to be capable of receiving a light passed through said focus plate and means for processing the outputs of said plurality of photoelectric converting means, and said second metering means includes at least one of said photoelectric converting means, said at least one photoelectric converting means being disposed to correspond to the central area of the object.
Claim 5
Dependent Claim 38 words
The device according to claim 1, wherein said second metering means includes photoelectric converting means provided so as to be capable of receiving the light from the object reflected by a film surface and/or a shutter curtain surface.
Claim 6
Dependent Claim 42 words
The device according to claim 1, wherein said first operational means includes: (a) a calculating circuit for effecting the subtraction of said first metering output and said second metering output; and (b) a circuit for holding the output of said calculating circuit.
Claim 7
Dependent Claim 28 words
The device according to claim 5, wherein said second operational means includes a circuit for adding together said second metering output and the output of said holding circuit.
Claim 8
Dependent Claim 168 words
A camera having an aperture of a phototaking lens stopped down from a maximum aperture opening in association with exposure operation and an exposure control device controllable said aperture for adjusting said aperture opening comprising: first metering means for effecting metering while dividing an object into a plurality of areas and for generating a plurality of photoelectric outputs corresponding to said areas and generating, on the basis of said photoelectric outputs, a first metering output which is a proper exposure value; second metering means for metering the light through said aperture opening at least until said stopping down being completed to generate a second metering output according to the intensity of said light varying with said stopping down; means for comparing said first metering output with said second metering output before the initiation of said stopping down and producing an output indicating a relative value between said first metering output and said second metering output; and means for displaying said relative value in response to said relational output.
Claim 9
Dependent Claim 168 words
A camera having an aperture of a phototaking lens stopped down from a maximum aperture opening in association with exposure operation and an exposure control device controllable said aperture for adjusting said aperture opening comprising: first metering means for effecting metering while dividing an object into a plurality of areas and for generating a plurality of photoelectric outputs corresponding to said areas and generating, on the basis of said photoelectric outputs, a first metering output which is a proper exposure value; second metering means for metering the light through said aperture opening at least until said stopping down being completed to generate a second metering output according to the intensity of said light varying with said stopping down; means for comparing said first metering output with said second metering output before the initiation of said stopping down and producing an output indicating a relative value between said first metering output and said second metering output; and means for displaying said relative value in response to said relational output.
Claim 10
Dependent Claim 105 words
The camera according to claim 7 which further comprises a finder optical means having a focus plate on which said phototaking lens forms an image of said object, wherein said firts metering means includes a plurality of photoelectric converting means, means for disposing said plurality of photoelectric converting means relative to said finder optical means so that each of said photoelectric converting means is capable of receiving the light from the different parts of said image one another and means for processing the output of said plurality of photoelectric converting means, and said second metering means includes at least one of said photoelectric converting means.
Claim 11
Dependent Claim 35 words
The camera according to claim 7 which further comprises a shutter curtain adjacent to a film surface, wherein said second metering means includes photoelectric converting means disposed to face the surface of said shutter curtain.
Claim 12
Dependent Claim 21 words
The device according to claim 7, further comprising second display means for displaying exposure information corresponding to said first metering output.
Claim 13
Dependent Claim 30 words
The device according to claim 7, wherein said comparing means includes means for subtracting said first metering output and said second metering output to produce said relative value indicating output.
Claim 14
Dependent Claim 104 words
The device according to claim 7, wherein said comparing means includes a circuit for calculating exposure information corresponding to the difference between said first metering output and said second metering output, and said display means includes: a circuit for operating an aperture value corresponding to said first metering output from said first metering output, film speed and a preset shutter speed; a circuit for operating an aperture value corresponding to said second metering output from the output of said calculating circuit and the aperture value corresponding to said first metering output; and means for displaying the aperture value corresponding to said second metering output.
Claim 15
Dependent Claim 163 words
An exposure control device of a camera having aperture control means for varying an aperture of a phototaking lens, said device comprising: first metering means for effecting metering while dividing an object into a plurality of areas and for generating a first metering output determining an exposure of the object on the basis of a plurality of photoelectric outputs corresponding to said areas; second metering means for metering a part area of said object and generating a second metering output corresponding to the brightness of said part area; first operational means for generating a first operation output corresponding to the difference between said first metering output and said second metering output; second operational means for generating a second operation output which is the second metering output during operation of said aperture control means having the first operation output added thereto; eliminating means capable of arbitrarily eliminating said first operation output; and means for effecting exposure control in response to said second operation output.
Claim 16
Dependent Claim 163 words
An exposure control device of a camera having aperture control means for varying an aperture of a phototaking lens, said device comprising: first metering means for effecting metering while dividing an object into a plurality of areas and for generating a first metering output determining an exposure of the object on the basis of a plurality of photoelectric outputs corresponding to said areas; second metering means for metering a part area of said object and generating a second metering output corresponding to the brightness of said part area; first operational means for generating a first operation output corresponding to the difference between said first metering output and said second metering output; second operational means for generating a second operation output which is the second metering output during operation of said aperture control means having the first operation output added thereto; eliminating means capable of arbitrarily eliminating said first operation output; and means for effecting exposure control in response to said second operation output.
Claim 17
Dependent Claim 73 words
The device according to claim 13, wherein said camera includes a finder optical means having a focus plate, and wherein said first metering means includes a plurality of photoelectric converting means provided so as to be capable of receiving a light passed through the focus plate and means for processing the outputs of said plurality of photoelectric converting means, and said second metering means includes at least one of said photoelectric converting means.
Claim 18
Dependent Claim 31 words
The device according to claim 14, wherein said one photoelectric converting means included in said second metering means is disposed so as to correspond to the central area of said object.
Claim 19
Dependent Claim 29 words
The device according to claim 14, wherein said second metering means includes means for arbitrarily selecting said one photoelectric converting means from among said plurality of photoelectric converting means.
Claim 20
Dependent Claim 183 words
A camera comprising: means for driving an aperture of a phototaking lens to cause a reduction of an aperture diameter; means for driving a shutter of said camera; first metering means for effecting metering while dividing an object into a plurality of metering areas and for generating a first metering output determining an exposure of the object on the basis of plurality of photoelectric outputs corresponding to said area; second metering means for metering said object through said aperture to generate a second metering output; first operational means for generating a first operation output including information on the difference between said first metering output and said second metering output both of which are generated before said reduction of said aperture diameter is caused; second operational means for adding said second metering output generated during said reduction of said aperture diameter and said first operation output and generating a second operation output; and exposure control means for determining at least one of an aperture value depended on said aperture and a time value depended on said shutter in response to said second operation output.
Claim 21
Dependent Claim 183 words
A camera comprising: means for driving an aperture of a phototaking lens to cause a reduction of an aperture diameter; means for driving a shutter of said camera; first metering means for effecting metering while dividing an object into a plurality of metering areas and for generating a first metering output determining an exposure of the object on the basis of plurality of photoelectric outputs corresponding to said area; second metering means for metering said object through said aperture to generate a second metering output; first operational means for generating a first operation output including information on the difference between said first metering output and said second metering output both of which are generated before said reduction of said aperture diameter is caused; second operational means for adding said second metering output generated during said reduction of said aperture diameter and said first operation output and generating a second operation output; and exposure control means for determining at least one of an aperture value depended on said aperture and a time value depended on said shutter in response to said second operation output.
Claim 22
Dependent Claim 56 words
The camera according to claim 17, wherein said exposure control means includes means for presetting said time value and means for blocking said aperture driving means to prevent said reduction of said aperture diameter when said diameter operation output and an output corresponding to said time value present by said presetting means assume a predetermined relation.
Claim 23
Dependent Claim 44 words
The camera according to claim 17, wherein said exposure control means includes means for determining a combination of said aperture value and said time value and means for controlling said aperture driving means and said shutter driving means in accordance with said combination respectively.
Claim 24
Dependent Claim 153 words
An exposure control device of a camera having aperture control means for varying an aperture of a phototaking lens, said device comprising: first metering means for effecting metering while dividing an object into a plurality of areas and for generating a first metering output determining an exposure of the object on the basis of a plurality of photoelectric outputs corresponding to said areas; second metering means for metering a part area of said object and generating a second metering output corresponding to the brightness of said part area; first operational means for generating a first operation output corresponding to the difference between said first metering output and said second metering output; second operational means for generating a second operation output which is the second metering output during operation of said aperture control means having the first operation output added thereto; and means for effecting exposure control in response to said second operation output.
Claim 25
Dependent Claim 153 words
An exposure control device of a camera having aperture control means for varying an aperture of a phototaking lens, said device comprising: first metering means for effecting metering while dividing an object into a plurality of areas and for generating a first metering output determining an exposure of the object on the basis of a plurality of photoelectric outputs corresponding to said areas; second metering means for metering a part area of said object and generating a second metering output corresponding to the brightness of said part area; first operational means for generating a first operation output corresponding to the difference between said first metering output and said second metering output; second operational means for generating a second operation output which is the second metering output during operation of said aperture control means having the first operation output added thereto; and means for effecting exposure control in response to said second operation output.
Claim 26
Dependent Claim 199 words
An exposure control device of a camera having aperture control means for varying an aperture of a phototaking lens, said device comprising: first metering means for effecting metering while dividing an object into a plurality of areas and for generating a first metering output determining an exposure of the object on the basis of a plurality of photoelectric outputs corresponding to said areas; second metering means for metering a part area of said object and generating a second metering output corresponding to the brightness of said part area; first operational means for generating a first operation output corresponding to the difference between said first metering output and said second metering output; second operational means for generating a second operation output which is the second metering output during operation of said aperture control means having the first operation output added thereto; mode selecting means for changing-over the exposure control mode between a first mode and a second mode; first control means for effecting exposure control in response to said second operation output when said first mode is being selected; and second control means effecting exposure control in response to said second metering output when said second mode is being selected.
Claim 27
Dependent Claim 199 words
An exposure control device of a camera having aperture control means for varying an aperture of a phototaking lens, said device comprising: first metering means for effecting metering while dividing an object into a plurality of areas and for generating a first metering output determining an exposure of the object on the basis of a plurality of photoelectric outputs corresponding to said areas; second metering means for metering a part area of said object and generating a second metering output corresponding to the brightness of said part area; first operational means for generating a first operation output corresponding to the difference between said first metering output and said second metering output; second operational means for generating a second operation output which is the second metering output during operation of said aperture control means having the first operation output added thereto; mode selecting means for changing-over the exposure control mode between a first mode and a second mode; first control means for effecting exposure control in response to said second operation output when said first mode is being selected; and second control means effecting exposure control in response to said second metering output when said second mode is being selected.

References Cited (Backward Citations)

US3973266A Cited
US4047187A Cited
US4176955A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1987-05-15 1987-11-14 1988-05-15 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1991-05-15 1991-11-14 1992-05-15 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1995-05-15 1995-11-14 1996-05-15 $7700.00 Window Closed / Lapsed

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