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JPS57185429A - Measuring device for shutter exposure time - Google Patents

Measuring device for shutter exposure time

Info

Publication number
JPS57185429A
JPS57185429A JP6930281A JP6930281A JPS57185429A JP S57185429 A JPS57185429 A JP S57185429A JP 6930281 A JP6930281 A JP 6930281A JP 6930281 A JP6930281 A JP 6930281A JP S57185429 A JPS57185429 A JP S57185429A
Authority
JP
Japan
Prior art keywords
exposure time
computer
shutter
drift
receiving
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.)
Pending
Application number
JP6930281A
Other languages
Japanese (ja)
Inventor
Ichiro Ono
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.)
Nikon Corp
Original Assignee
Nikon Corp
Nippon Kogaku KK
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 Nikon Corp, Nippon Kogaku KK filed Critical Nikon Corp
Priority to JP6930281A priority Critical patent/JPS57185429A/en
Publication of JPS57185429A publication Critical patent/JPS57185429A/en
Pending legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03B—APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FOR PROJECTING OR VIEWING THEM; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ACCESSORIES THEREFOR
    • G03B7/00—Control of exposure by setting shutters, diaphragms or filters, separately or conjointly
    • G03B7/08—Control effected solely on the basis of the response, to the intensity of the light received by the camera, of a built-in light-sensitive device
    • G03B7/091—Digital circuits
    • G03B7/093—Digital circuits for control of exposure time

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Control Of Exposure In Printing And Copying (AREA)
  • Exposure Control For Cameras (AREA)

Abstract

PURPOSE:To ensure the accurate measurement for shutter exposure time without receiving the effect of a drift, etc., by calculating the exposure time through the process of a computer in place of a comparator. CONSTITUTION:The shutter opening/closing waveform obtained by a photodetector PC is amplified up to a proper level through an amplifier AMP and then fed to an A/D converter ADC. This input signal is sampled synchronously with the clock pulse supplied from an oscillator OSC and then successively converted into the digital code to be supplied to a computer CP which functions as a storage arithmetic means. The computer CP stores the sample value corresponding to the sampling time and sets the reference value from the storage value. Then two sampling times corresponding to the two sample values equal to the reference value are obtained to calculate the exposure time. In such a way, the shutter exposure time can be measured with high accuracy and without receiving an effect of a drift, etc.
JP6930281A 1981-05-11 1981-05-11 Measuring device for shutter exposure time Pending JPS57185429A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP6930281A JPS57185429A (en) 1981-05-11 1981-05-11 Measuring device for shutter exposure time

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP6930281A JPS57185429A (en) 1981-05-11 1981-05-11 Measuring device for shutter exposure time

Publications (1)

Publication Number Publication Date
JPS57185429A true JPS57185429A (en) 1982-11-15

Family

ID=13398627

Family Applications (1)

Application Number Title Priority Date Filing Date
JP6930281A Pending JPS57185429A (en) 1981-05-11 1981-05-11 Measuring device for shutter exposure time

Country Status (1)

Country Link
JP (1) JPS57185429A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4598575A (en) * 1985-01-24 1986-07-08 Tektronix, Inc. Timer calibration method and apparatus

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4598575A (en) * 1985-01-24 1986-07-08 Tektronix, Inc. Timer calibration method and apparatus

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