JPS5770552A - Circuit for compensating deterioration of standard density pattern - Google Patents

Circuit for compensating deterioration of standard density pattern

Info

Publication number
JPS5770552A
JPS5770552A JP55145737A JP14573780A JPS5770552A JP S5770552 A JPS5770552 A JP S5770552A JP 55145737 A JP55145737 A JP 55145737A JP 14573780 A JP14573780 A JP 14573780A JP S5770552 A JPS5770552 A JP S5770552A
Authority
JP
Japan
Prior art keywords
signal
circuit
sent
density pattern
standard density
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
JP55145737A
Other languages
Japanese (ja)
Inventor
Hiroaki Ueno
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.)
Ricoh Co Ltd
Original Assignee
Ricoh Co Ltd
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 Ricoh Co Ltd filed Critical Ricoh Co Ltd
Priority to JP55145737A priority Critical patent/JPS5770552A/en
Publication of JPS5770552A publication Critical patent/JPS5770552A/en
Pending legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G15/00—Apparatus for electrographic processes using a charge pattern
    • G03G15/50—Machine control of apparatus for electrographic processes using a charge pattern, e.g. regulating differents parts of the machine, multimode copiers, microprocessor control
    • G03G15/5033—Machine control of apparatus for electrographic processes using a charge pattern, e.g. regulating differents parts of the machine, multimode copiers, microprocessor control by measuring the photoconductor characteristics, e.g. temperature, or the characteristics of an image on the photoconductor
    • G03G15/5037—Machine control of apparatus for electrographic processes using a charge pattern, e.g. regulating differents parts of the machine, multimode copiers, microprocessor control by measuring the photoconductor characteristics, e.g. temperature, or the characteristics of an image on the photoconductor the characteristics being an electrical parameter, e.g. voltage

Abstract

PURPOSE:To obtain a copy having always constant image quality, by compensating the change of detection voltage of photoreceptor surface potential of a standard density pattern due to aging change. CONSTITUTION:When a scanner returns, light emitted from the light emitting device of a standard density pattern deterioration detector 19 illuminates the standard density pattern 3, and its reflected light is detected with a photodiode 20. The time of returning of the scanner is detected with a sensor 21, and sent from a copying process control circuit 11 to sample holding circuits 23, 24 as a detection timing signal. The signal sent from the detector 19 passes through an amplifier 22, held with the circuit 23, and added to an addition circuit 25 as the correction signal Ea of a signal Eb for setting a reference latent image potential sent from the control signal 11. This output signal is compared with a signal Es sent from a surface potential detector 10 and the circuit 24 in a comparator 26, and its output is fed to the circuit 11, thus permitting a copy obtained to have always constant image quality.
JP55145737A 1980-10-20 1980-10-20 Circuit for compensating deterioration of standard density pattern Pending JPS5770552A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP55145737A JPS5770552A (en) 1980-10-20 1980-10-20 Circuit for compensating deterioration of standard density pattern

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP55145737A JPS5770552A (en) 1980-10-20 1980-10-20 Circuit for compensating deterioration of standard density pattern

Publications (1)

Publication Number Publication Date
JPS5770552A true JPS5770552A (en) 1982-05-01

Family

ID=15391969

Family Applications (1)

Application Number Title Priority Date Filing Date
JP55145737A Pending JPS5770552A (en) 1980-10-20 1980-10-20 Circuit for compensating deterioration of standard density pattern

Country Status (1)

Country Link
JP (1) JPS5770552A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS58224355A (en) * 1982-06-24 1983-12-26 Ricoh Co Ltd Method for correcting surface potential of photoreceptor of electrophotographic copying machine
JPS5912456A (en) * 1982-07-13 1984-01-23 Canon Inc Picture forming device

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS58224355A (en) * 1982-06-24 1983-12-26 Ricoh Co Ltd Method for correcting surface potential of photoreceptor of electrophotographic copying machine
JPS5912456A (en) * 1982-07-13 1984-01-23 Canon Inc Picture forming device

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