Patent US3887930A successfully refreshed from Google Patents.
US3887930A
Expired / Lapsed
US
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Light compensation for exposure control cameras
Assignee: Eastman Kodak Co
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Filing: 1974-07-12
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Granted: 1975-06-03
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Expires: 1994-07-12
Abstract
Abstract A camera includes a primary lens, a converter lens selectively usable to change the camera''s effective focal length and an exposure control device which includes a photocell. The converter lens, movable into and out of the camera''s optical path, has predetermined light loss and color contribution factors. A cover glass having approximately one-half the light loss factor and approximately the same color contribution factor as the converter lens is movable from a position affecting the light directed toward the photocell when the converter lens is in the camera''s optical path to a position affecting light directed toward the primary lens when the converter lens is removed from the optical path.
Inventors
- 👤 Richard J Bresson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 04:21
CPC Classifications
G; G03; G03B; G03B33/00; G03B7/00; G03B7/08; G03B7/099; G03B7/0993
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
161 words
In a camera having a primary lens; a converter lens having a predetermined light loss factor and a predetermined color contribution factor, said converter lens being movable between a taking position in optical alignment with said primary lens and a stored position out of optical alignment with said primary lens; and a photocell which is part of an exposure control device; the improvement comprising: optical means having a light loss factor of approximately onehalf that of said converter lens and a color contribution factor substantially the same as that of said converter lens; means for mounting said optical means for movement between a first position affecting light directed toward said primary lens and a second position affecting light directed toward said photocell; and means for moving said optical means to its first position when said converter lens is in its stored position and for moving said optical means to its second position when said converter lens is in its taking position.
Claim 2
Dependent Claim
161 words
In a camera having a primary lens; a converter lens having a predetermined light loss factor and a predetermined color contribution factor, said converter lens being movable between a taking position in optical alignment with said primary lens and a stored position out of optical alignment with said primary lens; and a photocell which is part of an exposure control device; the improvement comprising: optical means having a light loss factor of approximately onehalf that of said converter lens and a color contribution factor substantially the same as that of said converter lens; means for mounting said optical means for movement between a first position affecting light directed toward said primary lens and a second position affecting light directed toward said photocell; and means for moving said optical means to its first position when said converter lens is in its stored position and for moving said optical means to its second position when said converter lens is in its taking position.
Claim 3
Dependent Claim
161 words
In a camera having a primary lens; a converter lens having a predetermined light loss factor and a predetermined color contribution factor, said converter lens being movable between a taking position in optical alignment with said primary lens and a stored position out of optical alignment with said primary lens; and a photocell which is part of an exposure control device; the improvement comprising: optical means having a light loss factor of approximately one-half that of said converter lens and a color contribution factor substantially the same as that of said converter lens; means for mounting said optical means for movement between a first position affecting light directed toward said primary lens and a second position affecting light directed toward said photocell; and means for moving said optical means to its first position when said converter lens is in its stored position and for moving said optical means to its second position when said converter lens is in its taking position.
Claim 4
Dependent Claim
161 words
In a camera having a primary lens; a converter lens having a predetermined light loss factor and a predetermined color contribution factor, said converter lens being movable between a taking position in optical alignment with said primary lens and a stored position out of optical alignment with said primary lens; and a photocell which is part of an exposure control device; the improvement comprising: optical means having a light loss factor of approximately one-half that of said converter lens and a color contribution factor substantially the same as that of said converter lens; means for mounting said optical means for movement between a first position affecting light directed toward said primary lens and a second position affecting light directed toward said photocell; and means for moving said optical means to its first position when said converter lens is in its stored position and for moving said optical means to its second position when said converter lens is in its taking position.
Claim 5
Dependent Claim
166 words
In a camera having a primary lens; a converter lens having a predetermined light loss factor and a predetermined color contribution factor; a lens mount for said converter lens, said lens mount being movable in a plane perpendicular to the optical axis of said primary lens for moving said converter lens between a taking position in alignment with said optical axis and a stored position out of alignment with said optical axis; and a photocell which is part of an exposure control device; the improvement comprising: optical means having a light loss factor of approximately one-half that of said converter lens and having substantially the same color contribution factor as said coverter lens; and means on said lens mount for mounting said optical means in a position wherein said optical means is (1) aligned with said photocell when said converter lens is in its taking position and (2) aligned with the optical axis of said primary lens when said converter lens is in its stored position.
Claim 6
Dependent Claim
166 words
In a camera having a primary lens; a converter lens having a predetermined light loss factor and a predetermined color contribution factor; a lens mount for said converter lens, said lens mount being movable in a plane perpendicular to the optical axis of said primary lens for moving said converter lens between a taking position in alignment with said optical axis and a stored position out of alignment with said optical axis; and a photocell which is part of an exposure control device; the improvement comprising: optical means having a light loss factor of approximately one-half that of said converter lens and having substantially the same color contribution factor as said coverter lens; and means on said lens mount for mounting said optical means in a position wherein said optical means is (1) aligned with said photocell when said converter lens is in its taking position and (2) aligned with the optical axis of said primary lens when said converter lens is in its stored position.
Claim 7
Dependent Claim
148 words
In a camera having a casing defining an aperture; a primary lens aligned with said aperture; a shutter mechanism between said primary lens contribution sAid aperture; a converter lens having a predetermined color conbribution factor; a lens mount for said converter lens, said lens mount being movable for moving said converter lens between a taking position between said aperture and said shutter mechanism and a stored position out of alignment with said aperture; the improvement comprising: a cover glass having substantially the same color contribution factor as said converter lens; and means on said lens mount for mounting said cover glass in a position wherein said cover glass is (1) aligned with said aperture and between said aperture and said shutter mechanism when said converter lens is in its stored position and (2) out of alignment with said aperture when said converter lens is in its taking position.
Claim 8
Dependent Claim
148 words
In a camera having a casing defining an aperture; a primary lens aligned with said aperture; a shutter mechanism between said primary lens contribution sAid aperture; a converter lens having a predetermined color conbribution factor; a lens mount for said converter lens, said lens mount being movable for moving said converter lens between a taking position between said aperture and said shutter mechanism and a stored position out of alignment with said aperture; the improvement comprising: a cover glass having substantially the same color contribution factor as said converter lens; and means on said lens mount for mounting said cover glass in a position wherein said cover glass is (1) aligned with said aperture and between said aperture and said shutter mechanism when said converter lens is in its stored position and (2) out of alignment with said aperture when said converter lens is in its taking position.
Claim 9
Dependent Claim
35 words
The improvement as defined in claim 3 wherein said converter lens has a predetermined light loss factor and wherein said cover glass has a light loss factor of approximately one-half that of said converter lens.
Claim 10
Dependent Claim
193 words
In a camera having a casing defining first and second apertures; a primary lens aligned with said first aperture; a shutter mechanism between said primary lens and said first aperture; a photocell which is part of an exposure control device and which is aligned with said second aperture; a converter lens having a predetermined light loss factor; a lens mount for said converter lens and movable between a position in which said converter lens is in a taking position between said first aperture and said shutter mechanism and a position in which said converter lens is in a stored position out of alignment with said first aperture; the improvement comprising: a cover glass having a light loss factor of approximately one-half that of said converter lens; and means on said lens mount for mounting said cover glass in a position wherein said cover glass is (1) aligned with said first aperture and between said first aperture and said shutter mechanism when said converter lens is in its stored position and (2) aligned with said second aperture and between said second aperture and said photocell when said converter lens is in its taking position.
Claim 11
Dependent Claim
193 words
In a camera having a casing defining first and second apertures; a primary lens aligned with said first aperture; a shutter mechanism between said primary lens and said first aperture; a photocell which is part of an exposure control device and which is aligned with said second aperture; a converter lens having a predetermined light loss factor; a lens mount for said converter lens and movable between a position in which said converter lens is in a taking position between said first aperture and said shutter mechanism and a position in which said converter lens is in a stored position out of alignment with said first aperture; the improvement comprising: a cover glass having a light loss factor of approximately one-half that of said converter lens; and means on said lens mount for mounting said cover glass in a position wherein said cover glass is (1) aligned with said first aperture and between said first aperture and said shutter mechanism when said converter lens is in its stored position and (2) aligned with said second aperture and between said second aperture and said photocell when said converter lens is in its taking position.
References Cited (Backward Citations)
US3454323A
Cited
US3836934A
Cited
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| 3.5 Years (Year 4) | 1978-06-02 | 1978-12-02 | 1979-06-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-06-02 | 1982-12-02 | 1983-06-03 | $3760.00 | Window Closed / Lapsed |
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