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US4005443A Expired / Lapsed US ⏱️ 0.0 years remaining

Scanning device and method for automatic focusing

Assignee: Individual
•
Filing: 1975-09-11
•
Granted: 1977-01-25
•
Expires: 1995-09-11
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Abstract

Abstract A device for automatically focusing an image in an optical system such as a camera wherein a photosensitive array having a plurality of discrete sites is positioned in the focal plane of the optical system to dissect the image into segments and determine the light intensity at each segment. Means are interposed in the focal plane to vary the focus of the image, the illumination of the photosensitive array being dependent on the degree of focus of the image. The discrete sites have a charge produced thereon depending on the degree of illumination. Address means scan the photosensitive array and read out the charges on the discrete sites to form a pulse train. Discrimination means are connected to the address means to determine when the frequency of the pulse train is maximized to indicate sharp focusing of the image, as the focus of the image is varied.

Inventors

  • 👤 Fritz Albrecht

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 01:41
CPC Classifications
G; G02; G02B; G02B7/00; G02B7/28; G02B7/36

Claims Analysis

Total Claims: 7
Claim 1
Independent Claim 183 words
A device for automatically focusing an image in an optical system comprising: a photosensitive array having a plurality of discrete sites positioned in the focal plane of the optical system to dissect the image into segments crosswise and determine the light intensity at each segment, means interposed in the focal plane to vary the focus of the image, the illumination of the photosensitive array being dependent on the degree of focus of the image, said discrete sites having a charge produced depending on the degree of illumination, plural means to scan vertically and horizontally the photosensitive array and read out the charges on said discrete sites to form a pulse train, and discrimination means connected to the address means to determine when the frequency of the pulse train is maximized to indicate sharp focusing of the image, as the focus of the image is varied; means connected to the photosensitive array to delay activation of the discrimination means for a predetermined time sufficient to clear spurious charges from sites on the photosensitive array to preclude erroneous indication of sharp focusing of the image.
Claim 2
Independent Claim 183 words
A device for automatically focusing an image in an optical system comprising: a photosensitive array having a plurality of discrete sites positioned in the focal plane of the optical system to dissect the image into segments crosswise and determine the light intensity at each segment, means interposed in the focal plane to vary the focus of the image, the illumination of the photosensitive array being dependent on the degree of focus of the image, said discrete sites having a charge produced depending on the degree of illumination, plural means to scan vertically and horizontally the photosensitive array and read out the charges on said discrete sites to form a pulse train, and discrimination means connected to the address means to determine when the frequency of the pulse train is maximized to indicate sharp focusing of the image, as the focus of the image is varied; means connected to the photosensitive array to delay activation of the discrimination means for a predetermined time sufficient to clear spurious charges from sites on the photosensitive array to preclude erroneous indication of sharp focusing of the image.
Claim 3
Independent Claim 162 words
A device for automatically focusing an image in an optical system comprising: a photosensitive array having a plurality of discrete sites positioned in the focal plane of the optical system to dissect the image into segments crosswise and determine the light intensity at each segment, means interposed in the focal plane to vary the focus of the image, the illumination of the photosensitive array being dependent on the degree of focus of the image, said discrete sites having a charge produced depending on the degree of illumination, plural means to scan vertically and horizontally the photosensitive array and read out the charges on said discrete sites to form a pulse train, discrimination means connected to the address means to determine when the frequency of the pulse train is maximized to indicate sharp focusing of the image, as the focus of the image is varied; and means connected to the photosensitive array to normalize illumination thereof under excessive light or insufficient light conditions.
Claim 4
Independent Claim 162 words
A device for automatically focusing an image in an optical system comprising: a photosensitive array having a plurality of discrete sites positioned in the focal plane of the optical system to dissect the image into segments crosswise and determine the light intensity at each segment, means interposed in the focal plane to vary the focus of the image, the illumination of the photosensitive array being dependent on the degree of focus of the image, said discrete sites having a charge produced depending on the degree of illumination, plural means to scan vertically and horizontally the photosensitive array and read out the charges on said discrete sites to form a pulse train, discrimination means connected to the address means to determine when the frequency of the pulse train is maximized to indicate sharp focusing of the image, as the focus of the image is varied; and means connected to the photosensitive array to normalize illumination thereof under excessive light or insufficient light conditions.
Claim 5
Independent Claim 204 words
A device for automatically focusing an image in an optical system wherein the optical system is part of a camera comprising: a photosensitive array which is shaped to approximate the format of the image, said array having a plurality of discrete sites positioned in the focal plane of the optical system to dissect the image and to segments cross-wise and determine the light intensity at each segment, means interposed in the focal plane to vary the focus of the image, the illumination of the photosensitive array being dependent on the degree of focus of the image, said discrete sites having a charge produced depending on the degree of illumination, plural means to scan vertically and horizontally the photosensitive array and read out the charges on said discrete sites to form a pulse train, discrimination means connected to the address means to determine when the frequency of the pulse train is maximized to indicate sharp focusing of the image, as the focus of the image is varied; means connected to the photosensitive array to delay activation of the discrimination means for a predetermined time sufficient to clear spurious charges from sites on the photosensitive array to preclude erroneous indication of sharp focusing of the image.
Claim 6
Independent Claim 204 words
A device for automatically focusing an image in an optical system wherein the optical system is part of a camera comprising: a photosensitive array which is shaped to approximate the format of the image, said array having a plurality of discrete sites positioned in the focal plane of the optical system to dissect the image and to segments cross-wise and determine the light intensity at each segment, means interposed in the focal plane to vary the focus of the image, the illumination of the photosensitive array being dependent on the degree of focus of the image, said discrete sites having a charge produced depending on the degree of illumination, plural means to scan vertically and horizontally the photosensitive array and read out the charges on said discrete sites to form a pulse train, discrimination means connected to the address means to determine when the frequency of the pulse train is maximized to indicate sharp focusing of the image, as the focus of the image is varied; means connected to the photosensitive array to delay activation of the discrimination means for a predetermined time sufficient to clear spurious charges from sites on the photosensitive array to preclude erroneous indication of sharp focusing of the image.
Claim 7
Dependent Claim 35 words
A device for automatically focusing an image in an optical system as recited in claim 1, further comprising: means connected to the photosensitive array to normalize illumination thereof under excessive light or insufficient light conditions.

References Cited (Backward Citations)

US3909520A Cited
US3896304A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1980-01-25 1980-07-26 1981-01-25 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1984-01-25 1984-07-26 1985-01-25 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1988-01-25 1988-07-26 1989-01-25 $7700.00 Window Closed / Lapsed

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