Sanyo Electric Co., Ltd.

Nara Corporation

Institute of Science and Technology Sanyo Electric Co., Ltd.

Hajime Takashima

Atsushi Wada

Kuniyuki Tani

Jun Ohta

Yugo Nose

Keiichiro Kagawa

A pixel includes a photodiode, an overflow circuit, a first sensing circuit, and a second sensing circuit. The first sensing circuit charges and discharges a cathode capacitance by a photocurrent flowing through a photodiode, and amplifies an obtained voltage by a source follower amplifier so as to be outputted to a data line. The second sensing circuit charges and discharged the cathode capacitance by the photocurrent flowing through the photodiode, and outputs electric charge stored in the cathode capacitance via the data line. A pixel circuit is configured so that a first mode in which the first sensing circuit becomes active and a second mode in which the second sensing circuit becomes active can be switched. The first mode and the second mode are switched according to an amount of light received by the photodiode included in each pixel circuit. Gain is controlled according to the amount of light received, in the first mode, and the storage time is controlled in the second mode.

Photo detection device

In a photo detecting apparatus, a first capacitance is caused by a photo detecting element and the first capacitance is charged or discharged by current flowing through the photo detecting element. A second capacitance is connected in parallel with the photo detecting element, and the second capacitance charges or discharges an electric charge overflowing from the first capacitance. A current control element is connected to a terminal of the second capacitance on a side where the electric charge flows in, and the current control element delivers a current to cancel part of an electric charge when the electric charge overflowing from the first capacitance is stored in the second capacitance.

Photo detecting apparatus comprising a current control element

A pixel circuit includes a first detector which amplifies a voltage obtained by charging and discharging a capacitance with a photocurrent flowing through a photo detecting element and then outputs it to a first data line, and a second detector which outputs an electric charge stored in the capacitance by the photocurrent, to a second data line. The pixel circuit operates in a first operation mode where the first detector is activated, a second operation mode where the second detector is activated and an initialization mode where the photo detecting element is initialized. With a first transistor turned on, the second detector outputs an electric charge stored in the capacitance in the second operation mode, and in the initialization mode a reset voltage set in the second data line is applied to the other end of the photo detecting element to initialize the photo detecting element.

Photo detecting apparatus

Growing community of inventors

Atsugi, Japan

Hajime Takashima