In one example, an apparatus is provided. The apparatus includes a photodiode, a charge sensing unit, an analog-to-digital converter (ADC), and a controller. The controller is configured to: enable the photodiode to generate charge in response to incident light, accumulate at least a portion of the charge as residual charge until the photodiode becomes saturated by the residual charge, and transfer the remaining portion of the charge to the charge sensing unit as overflow charge if the photodiode becomes saturated by the residual charge. The controller is further configured to: generate, using the ADC, a first digital output based on the residual charge; after generating the first digital output, generate, using the ADC, a second digital output based on the overflow charge; and generate a digital representation of an intensity of the incident light based on at least one of the first digital output or the second digital output.

A counter is provided. A charge distributing circuit includes a first switch, a second switch, a third switch, a fourth switch, a third capacitor and a fourth capacitor. A first terminal of the first switch and a first terminal of the third switch are connected to a first input terminal of an operational amplifier. A second terminal of the first switch is connected to a first terminal of the third capacitor and a first terminal of the fourth switch. A second terminal of the third switch is connected to a first terminal of the fourth capacitor and a first terminal of the second switch. A second terminal of the third capacitor and a second terminal of the fourth capacitor are grounded. A second terminal of the second switch and a second terminal of the fourth switch are coupled to a reference voltage.

A method and a detection circuit. The detection circuit may include (a) a photodiode that is configured to convert radiation to a photodiode current; (b) a photodiode bias circuit that is configured to bias the photodiode; (c) a dynamic resistance circuit that has a first terminal and a second terminal; (d) a transimpedance amplifier that is configured to amplify an output current of the dynamic resistance circuit to provide an output voltage, wherein the second terminal is coupled to a negative input port of the amplification circuit; and (e) a conductor that is coupled between the first terminal and an anode of the photodiode.

A system for generating clock signals for a photonic quantum computing system includes a pump photon source configured to generate a plurality of pump photon pulses at a first repetition rate, a waveguide optically coupled to the pump photon source, and a photon-pair source optically coupled to the first waveguide. The system also includes a photodetector optically coupled to the photon-pair source and configured to generate a plurality of electrical pulses in response to detection of at least a portion of the plurality of pump photon pulses at the first repetition rate and a clock generator coupled to the photodetector and configured to convert the plurality of electrical pulses into a plurality of clock signals at the first repetition rate.

A UV detection device is removably attached to a surface of a structure and includes a photodetector to detect UV light incident on the structure. The UV detection device includes signal processing and a transmitter that wirelessly transmits UV detection data to a remote monitoring station where the detection signals are accumulated and analyzed to determine the total exposure of the structure to UV light.

An optical sensor includes at least one photodetector configured to be reverse biased at a voltage exceeding a breakdown voltage by an excess bias voltage. At least one control unit is configured to adjust the reverse bias of the at least one photodetector. A method of operating an optical sensor is also disclosed.

An optical sensor includes at least one photodetector configured to be reverse biased at a voltage exceeding a breakdown voltage by an excess bias voltage. At least one control unit is configured to adjust the reverse bias of the at least one photodetector. A method of operating an optical sensor is also disclosed.

A counter is provided. A charge distributing circuit includes a first switch, a second switch, a third switch, a fourth switch, a third capacitor and a fourth capacitor. A first terminal of the first switch and a first terminal of the third switch are connected to a first input terminal of an operational amplifier. A second terminal of the first switch is connected to a first terminal of the third capacitor and a first terminal of the fourth switch. A second terminal of the third switch is connected to a first terminal of the fourth capacitor and a first terminal of the second switch. A second terminal of the third capacitor and a second terminal of the fourth capacitor are grounded. A second terminal of the second switch and a second terminal of the fourth switch are coupled to a reference voltage.

An optical tomography imaging system includes a signal generator, at least one light emitter, at least one light receiver, a signal processor, and an image processor. The signal generator is configured to generate a periodic signal and a reference signal. The light emitter is configured to be activated by the periodic signal to generate an optical signal passing through an object under test. The light receiver is configured to receive and convert the optical signal passing through the object under test into an electrical signal. The signal processor is configured to generate a comparison signal according to the electrical signal and the reference signal. The image processor is configured to acquire a plurality of disassembled sine waves from the comparison signal and generate a reconstructed image according to the disassembled sine waves.

According to one embodiment, an automatic analyzing apparatus includes: a holder including a plurality of placement portions for a reaction tube to be placed thereon; a photometry unit for performing photometry on a solution inside the reaction tube, the photometry unit including a plurality of light emitters and a plurality of first light receivers respectively disposed in the plurality of placement portions; and processing circuitry configured to adjust quantities of light of the plurality of light emitters based on a light quantity signal from a second light receiver that receives light generated by the light emitters and guided by jig inserted into the placement portions.