An optical sensor, especially an artificial retina, that includes at least one photosensitive cell. Each cell includes a integration capacitor, a read circuit the operation of which depends on the charge of the integration capacitor, at least one MOS transistor operating subthreshold, and the drain-source current of which influences the charge on the integration capacitor, and at least one photodiode operating in photovoltaic mode and connected to the gate of this transistor, such that the drain-source current of the MOS transistor depends on the optical power received by the photodiode.

An optical sensor, especially an artificial retina, that includes at least one photosensitive cell. Each cell includes a integration capacitor, a read circuit the operation of which depends on the charge of the integration capacitor, at least one MOS transistor operating subthreshold, and the drain-source current of which influences the charge on the integration capacitor, and at least one photodiode operating in photovoltaic mode and connected to the gate of this transistor, such that the drain-source current of the MOS transistor depends on the optical power received by the photodiode.

A photometer and a method of performing photometric measurements with this photometer are described. The photometer comprises a photodetector providing a detector signal corresponding to an intensity of light received by the photodetector; and measurement electronics including: an amplifier and a signal processing device configured to determine and to provide a measurement result based on a measurement signal determined by the signal processing device as or based on an amplified detector signal provided by the amplifier. The signal processing device is configured to determine the measurement signal: a) as or based on the amplified detector signal provided by the amplifier being a multistage amplifier including a transimpedance converter and a voltage to current amplifier; and/or b) in form of a noise reduced signal determined by subtracting a previously determined noise offset included in the amplified detector signal from the amplified detector signal.

A photometer and a method of performing photometric measurements with this photometer are described. The photometer comprises a photodetector providing a detector signal corresponding to an intensity of light received by the photodetector; and measurement electronics including: an amplifier and a signal processing device configured to determine and to provide a measurement result based on a measurement signal determined by the signal processing device as or based on an amplified detector signal provided by the amplifier. The signal processing device is configured to determine the measurement signal: a) as or based on the amplified detector signal provided by the amplifier being a multistage amplifier including a transimpedance converter and a voltage to current amplifier; and/or b) in form of a noise reduced signal determined by subtracting a previously determined noise offset included in the amplified detector signal from the amplified detector signal.

Disclosed herein is a device including: at least one array of photoconductors, where each photoconductor is configured for exhibiting an electrical resistance dependent on an illumination of its light-sensitive region, where at least one photoconductor of the array is designed as characterizing photoconductor; at least one bias voltage source, where the bias voltage source is configured for applying at least one alternating bias voltage to the characterizing photoconductor or at least one direct current (DC) bias voltage to the characterizing photoconductor; at least one photoconductor readout circuit, where the photoconductor readout circuit is configured for determining of a response voltage of the characterizing photoconductor generated in response to the bias voltage, where the response voltage is proportional to a variable characterizing the array of photoconductors, where the photoconductor readout circuit is configured for determining of the response voltage of the characterizing photoconductor during operation of the array of photoconductors.

Disclosed herein is a device including: at least one array of photoconductors, where each photoconductor is configured for exhibiting an electrical resistance dependent on an illumination of its light-sensitive region, where at least one photoconductor of the array is designed as characterizing photoconductor; at least one bias voltage source, where the bias voltage source is configured for applying at least one alternating bias voltage to the characterizing photoconductor or at least one direct current (DC) bias voltage to the characterizing photoconductor; at least one photoconductor readout circuit, where the photoconductor readout circuit is configured for determining of a response voltage of the characterizing photoconductor generated in response to the bias voltage, where the response voltage is proportional to a variable characterizing the array of photoconductors, where the photoconductor readout circuit is configured for determining of the response voltage of the characterizing photoconductor during operation of the array of photoconductors.

A sensing pixel includes a single photon avalanche diode (SPAD) coupled between a first node and a second node, with a clamp diode being coupled between a turn-off voltage node and the second node. A turn-off circuit includes a sense circuit configured to generate a feedback voltage based upon a voltage at the turn-off voltage node, a transistor having a first conduction terminal coupled to the turn-off voltage node, a second conduction terminal coupled to ground, and a control terminal, and an amplifier having a first input coupled to a reference voltage, a second input coupled to receive the feedback voltage, and an output coupled to the control terminal of the transistor. A readout circuit is coupled to the SPAD by a decoupling capacitor.

This disclosure is directed to a high-speed avalanche photodiode device configured to detect single photons. The avalanche photodiode device may include a passive quenching circuitry. The passive quenching circuitry may include a quenching resistor having a resistivity spontaneously adaptive to a bias voltage applied across the quenching resistor. Such adaptive resistivity enables a fast response time for the avalanche photodiode device when used to detect single photos in Geiger mode.

An apparatus for measuring photon information and a photon measurement device are disclosed. The apparatus comprises a signal conversion module for converting an initial signal outputted by the photoelectric sensor into a converted signal in a voltage form, an integral comparison module for integrating a difference between the initial signal and a feedback signal from the negative feedback module and generating a comparison signal based on a magnitude relationship between a reference level and a combination result of an integral signal and the converted signal, wherein the integral signal is a signal for representing an integral of the difference between the initial signal and the feedback signal, a transmission control module for controlling the comparison signal to be transmit based on a clock signal to output a digital signal, a negative feedback module for converting the digital signal into the feedback signal and feeding the feedback signal back to the integral comparison module, and a measurement module for determining, based on the comparison signal and/or the digital signal, an arrival time of a high-energy photon detected by the photoelectric sensor. The apparatus and the device require few circuit components, and can realize high-precision time measurement.

An apparatus for measuring photon information and a photon measurement device are disclosed. The apparatus comprises a signal conversion module for converting an initial signal outputted by the photoelectric sensor into a converted signal in a voltage form, an integral comparison module for integrating a difference between the initial signal and a feedback signal from the negative feedback module and generating a comparison signal based on a magnitude relationship between a reference level and a combination result of an integral signal and the converted signal, wherein the integral signal is a signal for representing an integral of the difference between the initial signal and the feedback signal, a transmission control module for controlling the comparison signal to be transmit based on a clock signal to output a digital signal, a negative feedback module for converting the digital signal into the feedback signal and feeding the feedback signal back to the integral comparison module, and a measurement module for determining, based on the comparison signal and/or the digital signal, an arrival time of a high-energy photon detected by the photoelectric sensor. The apparatus and the device require few circuit components, and can realize high-precision time measurement.