Patent ID: 11953373
Assignee: JAPAN DISPLAY INC.
Field: Audio-visual technology (Electrical engineering)
Classification: CPC G  H | IPC G

Claim 6:
7. A sensing method using a sensor configured to output a sense signal, a value of the sense signal changing over time based on incident light,
wherein
the sensor comprises
a photodiode configured to generate current based on the incident light and including a terminal connected to an output terminal of the sensor,
a capacitor charged with the current,
a first transistor configured to set the voltage of the terminal of the photodiode to a reset voltage based on a reset value,
a second transistor configured to supply a constant current based on a charged voltage of the capacitor, and
a third transistor configured to be conductive for a certain period and output the constant current from the sensor,
a plurality of sensor units in a two-dimensional array of n rows×m columns, where n and m are arbitrary positive integers, the method comprising:

generating, by a first reset circuit having m reset units, a first reset signal when the value of the sense signal is less than or equal to a threshold, each of the m reset units being connected to the sensor units of each of the columns;
generating, by a second reset circuit having n second reset terminals, a second reset signal when the certain period is terminated, each of the n reset terminals being connected to the sensor units of each of the rows;
supplying the first reset signal or the second reset signal to a control terminal of the first transistor;
setting the value of the sense signal to the reset value when the value of the sense signal exceeds the threshold or when the certain period is terminated;
storing a first number of times of reset; and
calculating an amount of incident light of the certain period based on the value of the sense signal, the reset value, and the first number of times of reset.