US3860935A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Auto focus camera
Assignee: Honeywell Inc
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Filing: 1973-12-19
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Granted: 1975-01-14
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Expires: 1993-12-19
Abstract
Abstract An auto-focus camera including an objective lens device and a focal plane shutter has a first deflector device mounted on the focal plane shutter to reflect light from the objective lens device toward a second deflection device when the shutter is closed. The second deflection device, in turn, deflects radiation received thereby to form first and second auxiliary images of an object to be photographed on first and second arrays of light responsive elements, respectively. The second deflection device and the first and second arrays of light responsive elements are positioned out of the light path between the objective lens device and the focal plane shutter. As the objective lens is moved to vary the focus of the principal image to be formed on the light sensitive film of the camera, the intensity distribution of the first and second auxiliary images is also varied. The apparatus is so arranged that when the distributions of the first and second images are substantially equal, the objective lens is in a position to properly focus the principal image, of the object to be photographed, on the light sensitive film. A signal processing circuit connected between the light responsive elements and a control circuit responds to signals provided by the light responsive elements to determine when the distribution of the first and second auxiliary images are substantially equal at which time an ''''in focus'''' signal is provided to the control circuit to terminate the movement of the objective lens device. In another embodiment, the first and second arrays of light responsive elements are mounted on a nonreflective side of a reflex mirror in a single lens reflex camera.
Inventors
- 👤 Norman L Stauffer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 16:18
CPC Classifications
G; G02; G02B; G02B7/00; G02B7/28; G02B7/34
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
207 words
A camera means comprising: means defining a plane for receiving a light sensitive film; lens means for receiving light from an object to be photographed and forming a principal image of the object on the light sensitive film along a first light path; shutter means disposed between said lens means and the light sensitive film, said shutter means being selectively operable to open and close thereby selectively exposing said light sensitive film to the light from said lens means; first diversion means operable only when said shutter means is closed for reflecting said light from said lens means along a second light path; second diversion means in said second light path for receiving said reflected light and forming a plurality of discretely identifiable portions of radiation from which first and second auxiliary images are formed; first and second sensing means arranged to sense the intensities of said first and second auxiliary images, respectively, and to provide difference signals representative of the difference in intensities therebetween, which intensities vary as a function of the condition of focus of the principal image, and signal processing means connected to said first and second sensing means for providing an output signal indicative of the condition of focus of said principal image.
Claim 2
Dependent Claim
207 words
A camera means comprising: means defining a plane for receiving a light sensitive film; lens means for receiving light from an object to be photographed and forming a principal image of the object on the light sensitive film along a first light path; shutter means disposed between said lens means and the light sensitive film, said shutter means being selectively operable to open and close thereby selectively exposing said light sensitive film to the light from said lens means; first diversion means operable only when said shutter means is closed for reflecting said light from said lens means along a second light path; second diversion means in said second light path for receiving said reflected light and forming a plurality of discretely identifiable portions of radiation from which first and second auxiliary images are formed; first and second sensing means arranged to sense the intensities of said first and second auxiliary images, respectively, and to provide difference signals representative of the difference in intensities therebetween, which intensities vary as a function of the condition of focus of the principal image, and signal processing means connected to said first and second sensing means for providing an output signal indicative of the condition of focus of said principal image.
Claim 3
Dependent Claim
66 words
The camera means as set forth in claim 1 wherein said camera means further includes: means for moving said lens means whereby to vary the condition of focus of said principal image; and control means responsive to said output signal for controlling the position of said lens means whereby said lens means is moved to a positon which effects the best focus of said principal image.
Claim 4
Dependent Claim
25 words
The camera means as set forth in claim 1 wherein said first and second sensing means are fixedly mounted with respect to said camera means.
Claim 5
Dependent Claim
44 words
The camera means as set forth in claim 1 wherein said camera means is a single lens reflex camera including a reflex mirror having reflective and non-reflective faces, said first and second sensing means being mounted on the non-reflective face of said reflex mirror.
Claim 6
Dependent Claim
24 words
The camera means as set forth in claim 1 wherein each of said first and second sensing means includes a plurality of photoresponsive elements.
Claim 7
Dependent Claim
44 words
The camera means as set forth in claim 1 wherein said camera means includes a curtain-type shutter, said first diversion means being mounted on said curtain-type shutter in a position to lie in said first light path only when said shutter means is closed.
Claim 8
Dependent Claim
58 words
The camera means as set forth in claim 6 wherein said second diversion means includes first and second curvilinear reflector devices, said first curvilinear reflector device being operable to form said first auxiliary image on said first sensing means, and said second curvilinear reflecting device being operable to form said second auxiliary image on said second sensing means.
Claim 9
Dependent Claim
123 words
The camera means as set forth in claim 5 wherein said photoresponsive elements are photoresistors, each element of said first sensing means havIng a corresponding element in said second sensing means, the correspondence being based on the relative position of each light responsive element with respect to the sensing means of which it forms a part, said photoresistors of said first sensing means having a common terminal connected to means for connection to a potential of a first polarity, said photoresistors of said second sensing means having a common terminal connected to means for connection to a potential of an opposite polarity, the other terminals of corresponding photoresistors being connected together at separate common junctions to provide a plurality of said difference signals.
Claim 10
Dependent Claim
48 words
The camera means as set forth in claim 8 wherein said signal processing means includes squaring means responsive to each difference signal to provide a squared signal representative of the square of each difference signal and means for summing said squared difference signal to provide said output signals.
Claim 11
Dependent Claim
48 words
The camera means as set forth in claim 8 wherein said signal processing means includes absolute value means for providing an absolute value signal representative of the absolute value of each of said difference signals and means for summing said absolute valve signals to provide said output signal.
Claim 12
Dependent Claim
41 words
The camera means as set forth in claim 8 wherein said signal processing means includes a rectifier means fo rectifying each of said difference signals and summing means for summing all of said rectified difference signals to provide said output signal.
Claim 13
Dependent Claim
16 words
The camera means as set forth in claim 5 wherein said photoresponsive elements are photovoltaic cells.
Claim 14
Dependent Claim
111 words
The camera means as set forth in claim 12 wherein each of said photovoltaic cells includes a common terminal for connection to a common reference potential, each of said photovoltaic cells of said first sensing means having a corresponding photovoltaic cell in said second sensing means, the correspondence being based on the relative position of each photovoltaic cell with respect to the sensingmeans of which it forms a part, a plurality of differential amplifier means, the other terminals of corresponding photovoltaic cells being connected to separate terminals of separate ones of said differential amplifier means, said differential amplifier means being operable to provide said difference signals at the output terminals thereof.
Claim 15
Dependent Claim
49 words
The camera means as set forth in claim 13 wherein said signal processing means includes squaring means responsive to each difference signal for providing a squared signal representative of the square of each difference signal and summing means for summing said squared difference signals to provide said output signal.
Claim 16
Dependent Claim
48 words
The camera means as set forth in claim 13 wherein said signal processing means includes absolute value circuits for providing absolute value signals representative of the absolute value of each of said difference signals and summing means for summing said absolute value signals to provide said output signal.
Claim 17
Dependent Claim
38 words
The camera means as set forth in claim 13 wherein said signal processing means includes rectifier means for rectifying each of said difference signals and summing means for summing said rectified difference signals to provide said output signal.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-01-13 | 1978-07-15 | 1979-01-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-01-13 | 1982-07-15 | 1983-01-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-01-13 | 1986-07-15 | 1987-01-14 | $7700.00 | Window Closed / Lapsed |