GB2019595A - Automatic focusing - Google Patents

Automatic focusing

Info

Publication number
GB2019595A
GB2019595A GB7913648A GB7913648A GB2019595A GB 2019595 A GB2019595 A GB 2019595A GB 7913648 A GB7913648 A GB 7913648A GB 7913648 A GB7913648 A GB 7913648A GB 2019595 A GB2019595 A GB 2019595A
Authority
GB
United Kingdom
Prior art keywords
register
lens
rate
signals
camera
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
GB7913648A
Other versions
GB2019595B (en
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Polaroid Corp
Original Assignee
Polaroid Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Polaroid Corp filed Critical Polaroid Corp
Publication of GB2019595A publication Critical patent/GB2019595A/en
Application granted granted Critical
Publication of GB2019595B publication Critical patent/GB2019595B/en
Expired legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B7/00—Mountings, adjusting means, or light-tight connections, for optical elements
    • G02B7/28—Systems for automatic generation of focusing signals
    • G02B7/40—Systems for automatic generation of focusing signals using time delay of the reflected waves, e.g. of ultrasonic waves

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • Focusing (AREA)
  • Automatic Focus Adjustment (AREA)
  • Lens Barrels (AREA)

Abstract

An automatic camera focusing mechanism comprises a first electronic register for storing a number representative of the actual distance of the camera from the object (determined using bounced ultrasonic energy), a second electronic register for storing a number representative of the actual setting of the lens (determined using a grey code disc and grey-to-binary converter), a magnitude comparator which is responsive to a difference in register contents to operate a lens driving motor, and means for inhibiting the motor when the register contents are equal. In a cine camera, the content of the first electronic register varies at a rate dependent on the rate of actual distance determination, and the content of the second electronic register varies at a rate dependent on the rate of change of lens position. A reduction in lens hunting and a smoother change in focusing are effected by passing signals from the comparator to first and second shift registers and operating the motor, after a predetermined number of signals, in dependence on which register has the majority of signals.
GB7913648A 1978-04-25 1979-04-19 Automatic focusing Expired GB2019595B (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US89978578A 1978-04-25 1978-04-25

Publications (2)

Publication Number Publication Date
GB2019595A true GB2019595A (en) 1979-10-31
GB2019595B GB2019595B (en) 1982-09-29

Family

ID=25411561

Family Applications (1)

Application Number Title Priority Date Filing Date
GB7913648A Expired GB2019595B (en) 1978-04-25 1979-04-19 Automatic focusing

Country Status (9)

Country Link
JP (1) JPS54158226A (en)
AT (1) AT370886B (en)
AU (1) AU528360B2 (en)
CA (1) CA1124125A (en)
CH (1) CH646797A5 (en)
DE (1) DE2916569A1 (en)
FR (1) FR2424556B1 (en)
GB (1) GB2019595B (en)
IT (1) IT1112710B (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2503883A1 (en) * 1981-04-10 1982-10-15 West Electric Co AUTOMATIC FOCUSING DEVICE

Families Citing this family (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4335942A (en) * 1979-10-26 1982-06-22 Canon Kabushiki Kaisha Camera provided with automatic focus detector
JPS5749907A (en) * 1980-09-09 1982-03-24 Ricoh Co Ltd Noise eliminating circuit and in-focus detecting circuit
JPS5772115A (en) * 1980-10-23 1982-05-06 Canon Inc Output stablizing circuit for focus detector
JPS57128307A (en) * 1981-02-03 1982-08-09 Nippon Kogaku Kk <Nikon> Automatic focus adjuster
JPS587113A (en) * 1981-07-06 1983-01-14 Fuji Photo Optical Co Ltd Autofocusing device due to multipoint photometry
JPS58198009A (en) * 1982-05-14 1983-11-17 West Electric Co Ltd Ultrasonic auto-focusing device
JPS60135712U (en) * 1984-02-20 1985-09-09 三洋電機株式会社 auto focus camera
JPS60214320A (en) * 1984-04-11 1985-10-26 Kowa Co Automatic focus adjusting device
GB2161947B (en) * 1984-06-08 1988-06-29 Konishiroku Photo Ind Automatic focusing camera
JPS6127107U (en) * 1984-07-23 1986-02-18 ライトロン株式会社 auto focus device
JPH0224421A (en) * 1988-07-13 1990-01-26 Sadajiro Amiya Retaining wall concrete block and forming method thereof
JPH0430024A (en) * 1990-05-25 1992-02-03 Sekisui House Ltd Basement made of precast concrete

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4010479A (en) * 1974-07-10 1977-03-01 Asahi Kogaku Kogyo Kabushiki Kaisha Focusing apparatus for optical systems
DE2522757A1 (en) * 1975-05-22 1976-12-09 Walter Landsrath Automatic rangefinder for cambers - using transmission time of ultrasound to measure object range
US4078171A (en) * 1976-06-14 1978-03-07 Honeywell Inc. Digital auto focus

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2503883A1 (en) * 1981-04-10 1982-10-15 West Electric Co AUTOMATIC FOCUSING DEVICE

Also Published As

Publication number Publication date
IT7922114A0 (en) 1979-04-24
JPS54158226A (en) 1979-12-13
IT1112710B (en) 1986-01-20
CH646797A5 (en) 1984-12-14
FR2424556B1 (en) 1986-01-10
DE2916569A1 (en) 1979-11-08
GB2019595B (en) 1982-09-29
AU528360B2 (en) 1983-04-28
DE2916569C2 (en) 1990-11-08
CA1124125A (en) 1982-05-25
JPS6226449B2 (en) 1987-06-09
ATA309979A (en) 1982-09-15
AU4628679A (en) 1979-11-01
AT370886B (en) 1983-05-10
FR2424556A1 (en) 1979-11-23

Similar Documents

Publication Publication Date Title
GB2019595A (en) Automatic focusing
JPS5644803A (en) System measuring for thickness of nonmetallic sheet like object
US4294531A (en) Auto-focus movie camera
JPS5495117A (en) Automatic light-exposure type pickup unit
JPS5697325A (en) Focus detecting method of camera
JPS51120725A (en) Automatic forcusing camera
JPS5387217A (en) Focusing device
JPS5351736A (en) Film sensitivity presetting system for exposure condition determining circuit
JPS5319805A (en) Automatic focusing optical device
JPS57169710A (en) Automatic focusing device
JPS5538610A (en) Magnetic disc unit
JPS5636632A (en) Self-timer for automatic focusing control camera
JPS53131007A (en) Automatic focusing device
JPS52153454A (en) Automatic focus controlling apparatus
JPS5317329A (en) Lens barrel with change mechanism between tracking control and macro photograph
GB2013353A (en) Camera focus control system
SU1015412A1 (en) Method of checking moving object position
JPS5538583A (en) Exposure control mechanism in cine camera
JPS60107839U (en) Camera shutter control circuit
SU1013383A2 (en) Apparatus for monitoring position of hoistable container in mine shaft
JPS54116223A (en) Exposure time control apparatus
JPS6454409A (en) Automatic focusing camera
JPS56138733A (en) Automatic discriminating device for discriminating simultaneous printing and extra printing
JPS56127255A (en) Automatic operating device
JPS56111840A (en) Autofocus ultrasonic camera

Legal Events

Date Code Title Description
PCNP Patent ceased through non-payment of renewal fee