Patent classifications
G01J2001/4466
Open-loop photodiode gain regulation
Apparatus and associated methods relate to an open-loop control circuit (OLCC) configured to determine a photodiode element (PDE) drive voltage as a function of a commanded photodiode gain level and a measured temperature signal. In an illustrative example the OLCC may receive a current temperature of an APD element. The OLCC may, for example, receive a commanded gain for the APD relative to a predetermined reference gain. The OLCC may, for example, retrieve a predetermined efficiency characteristic (PEC) of the APD based on the current temperature. If the temperature corresponds to a substantially non-linear portion of the PEC, the OLCC may, for example, determine the drive voltage as a function of the temperature and the commanded gain based on the PEC. Various embodiments may advantageously provide direct control of output gain of photodiodes over a wide dynamic range of temperature associated with the photodiode.
IMPROVEMENTS IN SPAD-BASED PHOTODETECTORS
An integrated photodetecting optoelectronic semiconductor component configured to deliver an output signal indicative of the intensity of light irradiating the component. The component may include a SPAD-based main detection device configured to detect incoming photons and to deliver an output signal based on the detected photons. The component may also include a SPAD-based reference detection device proximate to the main detection device where the reference detection device has the same electro-optical behaviour as the main detection device, is configured to detect incoming photons, configured to deliver a reference signal based on the detected photons, and has a light inlet for incoming photons. The component may also include a neutral density filtering device and a controller configured to determine a nominal output signal, compare the nominal output signal with the output signal delivered by the main detection device, and adjust an operating parameter based on the comparison.
PHOTON AVALANCHE DIODE HAVING FIRST, SECOND, AND THIRD DIODES FORMED IN A SEMICONDUCTOR BODY
A photon avalanche diode includes: first, second, and third diodes formed in a semiconductor body, the second diode being a photodiode; a main cathode terminal connected to the cathode of the first diode; a main anode terminal connected to the anode of the third diode; an auxiliary cathode terminal connected to the cathode of the second and third diodes; and an auxiliary anode terminal connected to the anode of the first and second diodes. The main anode terminal is electrically connected to ground or a reference potential. The main cathode terminal is electrically connected to a voltage which causes a photocarrier multiplication region to form within the semiconductor body. The auxiliary anode terminal is electrically connected to ground or to a read-out circuit. The auxiliary cathode terminal is electrically connected to a constant bias voltage less than a voltage applied to the main cathode terminal.
LINEAR REGULATION OF SPAD SHUTOFF VOLTAGE
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.
Neuromorphic single photon avalanche detector (SPAD) array microchip
Described is a Single-Photon Avalanche Diode (SPAD) array microchip comprising: a plurality of SPAD sensors; and a triggering circuit configured to detect and read out the triggering order of SPAD sensors over a timing interval wherein the timing interval comprises one or more frames. An event based neuromorphic SPAD array microchip is also described. The chip architecture and triggering methodology takes a local group of SPAD sensors connected in a certain way and by using simple digital circuits emulating how neurons behave, patterns within a local receptive field are identified. Only when these unique patterns or features are identified are “events” triggered for each receptive field in the order they occur, or in an asynchronous manner. Each neuromorphic circuit (or collection of silicon neurons) act over overlapping receptive fields, and are tiled across the entire visual spatial field of the SPAD array to a form a convolution layer.
Apparatus for measuring photon information and photon measurement device
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.
Single-photon avalanche diode-based time-of-flight sensor with two modes of operation
A method may include operating a single-photon avalanche diode (SPAD) in a first mode to determine a light intensity level associated with the SPAD, operating the SPAD in a second mode wherein a reverse bias voltage is applied in the second mode to bias the SPAD beyond its breakdown voltage, such that the SPAD operates in a detection mode, and determining a magnitude of the bias voltage applied to the SPAD in the second mode based on the light intensity level determined in the first mode.
INTEGRATED SEMICONDUCTOR OPTOELECTRONIC COMPONENT
An integrated semiconductor optoelectronic component for sensing ambient light levels includes a silicon photomultiplier configured to deliver an output signal indicative of the intensity of the light that irradiates the component. The silicon photomultiplier has an active surface area for light detection. The component also includes an optical filter covering the active surface area of the silicon photomultiplier. The optical filter is adapted to selectively transmit light onto the active surface area as a function of wavelength. The optical filter is a scotopic filter and has a spectral transmission curve that mimics the spectral response of the human eye under low-light conditions. The component further includes readout electronics for processing the output signal of the silicon photomultiplier.
PHOTOELECTRIC CONVERSION APPARATUS
A photoelectric conversion apparatus includes a plurality of pixels each including a respective avalanche photodiode, wherein the plurality of pixels includes an active pixel that outputs a photon detection signal according to detection of a photon and an inactive pixel that does not output the photon detection signal, and wherein the photoelectric conversion apparatus further includes a control unit that recharges a voltage to be applied between an anode and a cathode of the avalanche photodiode of the inactive pixel.
PHOTOELECTRIC CONVERSION DEVICE
A photoelectric conversion device includes a photodiode configured to perform avalanche multiplication, a recharging circuit configured to perform a recharging operation to bring the photodiode after the avalanche multiplication into a state in which the avalanche multiplication can be performed again based on a first control signal including pulses that periodically repeat transitions from a first level to a second level, and a counter configured to count the number of occurrences of the avalanche multiplication by being enabled based on a second control signal. Before the counter is enabled based on the second control signal, the first control signal transitions from the first level to the second level and transitions from the second level to the first level.