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US4825239A Expired / Lapsed US ⏱️ 0.0 years remaining

Distance detection method and apparatus

Assignee: Canon Inc
•
Filing: 1988-08-01
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Granted: 1989-04-25
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Expires: 2008-08-01
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Abstract

Abstract A distance detection apparatus comprising: a distance detection unit for detecting information on a distance to an object, a controller for operating the detection means a plurality of times, and for processing a plurality of information on the distance and outputting an optimum distance information; a status detector for detecting a status of the object for outputting information on the status; and a circuit for altering an information processing method of the controller, in accordance with the output of the status detection means.

Inventors

  • 👤 Yasuo Suda
  • 👤 Akira Akashi
  • 👤 Akira Ishizaki
  • 👤 Hiroshi Ohmura
  • 👤 Keiji Ohtaka

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-02 07:52
CPC Classifications
G; G02; G02B; G02B7/00; G02B7/28; G02B7/34

Claims Analysis

Total Claims: 20
Claim 1
Independent Claim 80 words
A focus state detection method comprising steps of: detecting information on a focus state a plurality of times; storing the detected information; comparing the latest detected information with a predetermined information; adjusting the focus state in accordance with the latest detected information when focus state is worse than a predetermined state; and adjusting the focus state in accordance with a plurality of stored information detected before the immediately previous detection when the focus state is better than the predetermined state.
Claim 2
Dependent Claim 80 words
A focus state detection method comprising steps of: detecting information on a focus state a plurality of times; storing the detected information; comparing the latest detected information with a predetermined information; adjusting the focus state in accordance with the latest detected information when focus state is worse than a predetermined state; and adjusting the focus state in accordance with a plurality of stored information detected before the immediately previous detection when the focus state is better than the predetermined state.
Claim 3
Dependent Claim 44 words
A focus state detection method according to claim 1, wherein said second adjusting step includes a step of comparing the immediately previously detected information with a second predetermined information and a step of comparing the next previously detected information with a third predetermined information.
Claim 4
Dependent Claim 104 words
A focus state detection method comprising steps of: detecting information on a focus state a plurality of times; storing the detected information; detecting a contrast of an object; storing a signal for maintaining focus adjustment as a latest signal when the detected contrast is low; comparing the latest detected information with a predetermined information; adjusting the focus state in accordance with the latest detected information when the focus state is worse than a predetermined state; and adjusting the focus state in accordance with a plurality of stored information detected before the immediately previous detection when the focus state is better than the predetermined state.
Claim 5
Dependent Claim 104 words
A focus state detection method comprising steps of: detecting information on a focus state a plurality of times; storing the detected information; detecting a contrast of an object; storing a signal for maintaining focus adjustment as a latest signal when the detected contrast is low; comparing the latest detected information with a predetermined information; adjusting the focus state in accordance with the latest detected information when the focus state is worse than a predetermined state; and adjusting the focus state in accordance with a plurality of stored information detected before the immediately previous detection when the focus state is better than the predetermined state.
Claim 6
Dependent Claim 44 words
A focus state detection method according to claim 3 wherein said second adjusting step includes a step of comparing the immediately previously detected information with a second predetermined information and a step of comparing the next previously detected information with a third predetermined information.
Claim 7
Independent Claim 103 words
An apparatus for causing an optical device to focus an object, comprising: detection means for detecting information on a focus detection condition of the optical device; information processing means for operating said detection means a plurality of times and for processing each said information detected by said detection means to form a plurality of focus informations used for causing the optical device to focus on the object; and selecting means for comparing said focus informations with a predetermined condition in a predetermined order to select one of said focus informations to provide a signal, as focus adjustment information, corresponding to the selected information.
Claim 8
Independent Claim 103 words
An apparatus for causing an optical device to focus an object, comprising: detection means for detecting information on a focus detection condition of the optical device; information processing means for operating said detection means a plurality of times and for processing each said information detected by said detection means to form a plurality of focus informations used for causing the optical device to focus on the object; and selecting means for comparing said focus informations with a predetermined condition in a predetermined order to select one of said focus informations to provide a signal, as focus adjustment information, corresponding to the selected information.
Claim 9
Dependent Claim 40 words
An apparatus according to claim 5, further comprising: object state detection means for detecting a state of the object and, in accordance with the object state detected, for storing as focus information, information for overriding the selected focus adjustment information.
Claim 10
Dependent Claim 17 words
An apparatus according to claim 6, wherein said object state detection means detects contrast of the object.
Claim 11
Dependent Claim 59 words
An apparatus according to claim 5, wherein said predetermined condition of said selection means comprises an in-focus state, a state slightly deviated from the in-focus state, and a state largely deviated from the in-focus state, and wherein when the current information of said focus information indicates the state largely deviated from the in-focus state, the current information is selected.
Claim 12
Dependent Claim 41 words
An apparatus according to claim 5, wherein said information processing means includes a memory, and wherein said selecting means selects between one of two informations from previous detection operations stored in said memory and the information from the latest detection operation.
Claim 13
Independent Claim 146 words
An apparatus for causing an optical device to focus an object, comprising: detection means for detecting information on a focus detection condition of the optical device; information processing means for operating said detection means a plurality of times and for processing each said information detected by said detection means to form a plurality of focus informations used for causing the optical device to focus on the object; and discrimination means for discriminating the focus information in one of an in-focus state, a state largely deviated from the in-focus state, and a state slightly deviated from the in-focus state, said discrimination means first discriminating the current focus information and thereafter discriminating the other focus information, and said discrimination means selecting the current focus information regardless of the content of the other focus information when the current focus information indicates the state largely deviated from the in-focus state.
Claim 14
Independent Claim 146 words
An apparatus for causing an optical device to focus an object, comprising: detection means for detecting information on a focus detection condition of the optical device; information processing means for operating said detection means a plurality of times and for processing each said information detected by said detection means to form a plurality of focus informations used for causing the optical device to focus on the object; and discrimination means for discriminating the focus information in one of an in-focus state, a state largely deviated from the in-focus state, and a state slightly deviated from the in-focus state, said discrimination means first discriminating the current focus information and thereafter discriminating the other focus information, and said discrimination means selecting the current focus information regardless of the content of the other focus information when the current focus information indicates the state largely deviated from the in-focus state.
Claim 15
Independent Claim 123 words
An apparatus for detecting a focus adjusting state of an optical device, comprising: light receiving means for generating a signal with respect to a light flux which is received by said light receiving means through said optical device; information processing means for generating condition information concerning a focus adjusting state of said optical device, said information processing means generating a plurality of said condition information by time serially operating said light receiving means plural times; and comparing means for comparing a latest condition information with a predetermined condition, said comparing means outputting said latest condition information when said predetermined condition is satisfied, and for comparing preceding condition information with a condition representing the focus adjusting state when said predetermined condition is not satisfied.
Claim 16
Independent Claim 123 words
An apparatus for detecting a focus adjusting state of an optical device, comprising: light receiving means for generating a signal with respect to a light flux which is received by said light receiving means through said optical device; information processing means for generating condition information concerning a focus adjusting state of said optical device, said information processing means generating a plurality of said condition information by time serially operating said light receiving means plural times; and comparing means for comparing a latest condition information with a predetermined condition, said comparing means outputting said latest condition information when said predetermined condition is satisfied, and for comparing preceding condition information with a condition representing the focus adjusting state when said predetermined condition is not satisfied.
Claim 17
Dependent Claim 22 words
An apparatus according to claim 11, wherein said predetermined condition is determined on the basis of the contrast of an object image.
Claim 18
Dependent Claim 21 words
An apparatus according to claim 11, wherein said condition representing the focus adjusting state is a condition of an in-focus state.
Claim 19
Independent Claim 108 words
An apparatus for focus adjusting an optical device, comprising: first means for outputting a condition signal representing a focusing condition state of said optical device upon receiving a light flux through said optical device; second means for making said first means output a plurality of condition signal by time serially operating said first means plural times; third means for memorizing the plurality of condition signals; fourth means for producing adjusting information concerning an adjusting state of said optical device on the basis of said plurality of condition signals memorized by said third means; and fifth means for outputting information concerning a latest condition signal or said adjusting information.
Claim 20
Independent Claim 108 words
An apparatus for focus adjusting an optical device, comprising: first means for outputting a condition signal representing a focusing condition state of said optical device upon receiving a light flux through said optical device; second means for making said first means output a plurality of condition signal by time serially operating said first means plural times; third means for memorizing the plurality of condition signals; fourth means for producing adjusting information concerning an adjusting state of said optical device on the basis of said plurality of condition signals memorized by said third means; and fifth means for outputting information concerning a latest condition signal or said adjusting information.

References Cited (Backward Citations)

US4492448A Cited
US4542289A Cited
US4492449A Cited
US4560863A Cited
US4614865A Cited
US4561750A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1992-04-24 1992-10-24 1993-04-25 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1996-04-24 1996-10-24 1997-04-25 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2000-04-24 2000-10-24 2001-04-25 $7700.00 Window Closed / Lapsed

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