Apparatus having a photoelectric conversion element and a transistor, in which the duration of the on time of the transistor is based on a detected temperature of the conversion element or transistor
AssigneeCanon Kabushiki Kaisha
InventorsToshio Kameshima, Noriyuki Kaifu
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Abstract
A photoelectric conversion apparatus has a photoelectric conversion element, a transistor for transferring a signal from the photoelectric conversion element, and a driver for supplying a drive pulse to the control electrode of the transistor. A temperature of the photoelectric conversion element and/or transistor is measured. The measured temperature is compared to a reference temperature, and based on that comparison, a length of the supplied drive pulse is made shorter or longer.
Claims25
A photoelectric conversion apparatus comprising a photoelectric conversion element for converting an incident light signal to an electric signal, a transistor for performing a transfer control of the electric signal from the photoelectric conversion element, and driving means for applying a transfer control signal having a pulse length to a control electrode of the transistor, said photoelectric conversion apparatus comprising:
- control means for controlling said driving means so as to detect a temperature of said photoelectric conversion element or said transistor and to cause a change in the pulse length of the transfer control signal, so that in a case where the detected temperature is higher than a reference temperature, the pulse length of the transfer control signal is made shorter relative to a pulse length corresponding to the reference temperature, thereby shortening a transfer time of the electric signal, and in a case where the detected temperature is lower than the reference temperature, the pulse length of the transfer control signal is made longer relative to the pulse length corresponding to the reference temperature, thereby lengthening the transfer time of the electric signal.
A driving method of a photoelectric conversion apparatus having a photoelectric conversion element, a transistor for transferring a signal from said photoelectric conversion element, and driving means for supplying a drive pulse having a pulse length to a control electrode of said transistor, said driving method comprising:
- a first step of measuring a temperature of said photoelectric conversion element or transistor;
- and
- a second step of comparing a measured temperature obtained in the first step with a reference temperature, and changing the pulse length of said drive pulse according to the compared temperatures.
An image input apparatus comprising:
- a two dimensional area sensor having a plurality of pixels each comprising a thin film transistor for converting an incident quantity of X-rays into an electric signal and for outputting the electric signal;
- temperature detecting means arranged for obtaining information regarding temperature of at least one of said plurality of pixels;
- and
- control means for determining a pulse length of a drive pulse to be applied to a control electrode of the thin film transistor, wherein the drive pulse length is based on the temperature information obtained from said temperature detecting means.
Dependencies are inferred from the claim text.