Photoconversion device having reset control circuitry

A control circuit for a photoconversion cell which cell has a photoconversion element which stores charges in a control region thereof in response to incident light and a reset switch means for resetting the control region, the control circuit comprising:

• connection means connecting to a control terminal of the reset switch means and a main terminal of the reset switch means;
• and
• means for applying a turn-on voltage for the reset switch to the connection means connecting to said main terminal of the reset switch means to vary a voltage at the main electrode of the reset switch while keeping a voltage at the control terminal of the reset switch substantially constant.

A method of resetting a photoconversion element which stores charge in a control region thereof in response to incident light, comprising turning on a reset switch having first and second main terminals and a control terminal by applying a turn-on voltage to its first main terminal to cause a variation in a voltage of one of the main terminals of the reset switch while keeping a voltage at the control terminal of the reset switch substantially constant.

A photoconversion device comprising:

• a plurality of rows of photoconversion elements, each of which comprises first and second main electrode regions and a control region, charges being stored in the control region in response to incident light;
• first reset means for conducting a first reset operation at the same time for the photoconversion elements of more than one of the rows;
• a plurality of reset switches, one coupled to each of said photoconversion elements and having at least one main electrode and a control electrode, each reset switch for resetting the corresponding photoconversion element by varying the voltage at said main electrode thereof while keeping the voltage at said control electrode thereof substantially constant.

A control circuit for a photoconversion array having (i) a plurality of rows of photoconversion elements each of which stores charges in a control region thereof in response to incident light and (ii) a plurality of reset switches one coupled to each of said photoconversion elements and having at least one main electrode and a control electrode, the control circuit comprising circuitry to reset photoconversion elements of more than one of the rows at the same time, said reset circuitry varying the voltage at said main electrode of said reset switch while keeping the voltage at said control electrode of said reset switch substantially constant.

A method of operating a photoconversion device having (i) a plurality of rows of photoconversion elements each of which stores charge in a control region thereof in response to incident light and (ii) a plurality of reset switches each coupled to a corresponding photoconversion element and having a main electrode and a control electrode, the method comprising the step of resetting photoconversion elements of a plurality of rows at the same time using said reset switch, each reset switch being turned on to reset the corresponding photoconversion element by varying the voltage at said reset switch main electrode while keeping the voltage at said reset switch control electrode substantially constant.

A control circuit for a photoconversion element which has (i) first and second main electrode regions and a control region in which charge is stored in response to incident light and (ii) a reset switch having a main electrode and a control electrode, the circuit comprising:

• connection means for connected to the photoconversion element;
• and
• means for altering the potential of the first main electrode region to forward bias the control region relative to the first main electrode region, said means for altering turning-on said reset switch by varying the voltage at said reset switch main electrode while keeping the voltage at said reset switch control electrode substantially constant.

A method of resetting a photoconversion element having (i) first and second main electrode regions and a control region on which charges are accumulated in response to incident light and (ii) a reset switch having a main electrode and a control electrode, in which a reset operation for the control region includes the step of altering the potential of the first main electrode region to forward bias the control region relative to the first main electrode region by turning on the reset switch by varying the voltage of the reset switch main electrode while keeping the voltage of the reset switch control electrode substantially constant.