A light pixel projection module includes a pixel light source, a light pixel projection assembly for projecting a light pixel generated by the light pixel generating assembly, and an optical time-of-flight (ToF) measurement assembly for measuring a distance between the projection module and an external object. The ToF measurement assembly includes a ToF light source, a beam splitting optical device for splitting an incident light beam into a reflected main beam component and a transmitted and attenuated secondary beam component, and an APD-based ToF photodetector for light detection. The beam splitting optical device is arranged in the optical path of light beams emitted by the ToF light source such that it splits each light beam emitted by the ToF light source into a main beam component leaving the module and heading towards the external object and a secondary beam component remaining within the module and hitting the ToF photodetector.

The present disclosure relates to limitation of noise on light detectors using an aperture. One example embodiment includes a system. The system includes a lens disposed relative to a scene and configured to focus light from the scene onto a focal plane. The system also includes an aperture defined within an opaque material disposed at the focal plane of the lens. The aperture has a cross-sectional area. In addition, the system includes an array of light detectors disposed on a side of the focal plane opposite the lens and configured to intercept and detect diverging light focused by the lens and transmitted through the aperture. A cross-sectional area of the array of light detectors that intercepts the diverging light is greater than the cross-sectional area of the aperture.

A photon detection device having a high light detection efficiency. The photon detection device includes a first light reception part which receives a gate signal and outputs a first signal; a second light reception part which receives a gate signal and outputs a second signal; and a determination part which determines whether or not a photon is received, on the basis of the first signal from the first light reception part and the second signal from the second light reception part. The photon is incident on the first light reception part among the first light reception part and the second light reception part, and the breakdown voltage of the second light reception part is higher than the breakdown voltage of the first light reception part.

A light receiving device according to the present disclosure includes: a light receiving element that generates a signal in response to reception of a photon; a readout circuit that reads out a signal generated by the light receiving element; and a protection circuit that is provided between the light receiving element and the readout circuit and protects a circuit element of the readout circuit from overvoltage. Further, a distance measuring device according to the present disclosure includes a light receiving device of the above configuration.

A photon detection device according to an aspect of the present invention includes: a superconducting photon detector array in which a plurality of superconducting photon detectors (SPDs) are arranged; a plurality of first transmission lines connected to the plurality of SPDs and configured to transmit a detection current output from each of the plurality of SPDs; an address information generation circuit connected to the plurality of first transmission lines and configured to generate, based on the detection current, an address information signal that specifies a superconducting photon detector from which the detection current is output; a second transmission line magnetically coupled to all of the plurality of first transmission lines; and a time information generation circuit connected to the second transmission line and configured to generate, based on the detection current, a time information signal indicating a time at which a photon is incident on the plurality of superconductive photon detection SPDs.

A superconducting nanowire single photon detector (SNSPD) device includes a substrate having a top surface, an optical waveguide on the top surface of the substrate to receive light propagating substantially parallel to the top surface of the substrate, a seed layer of metal nitride on the optical waveguide, and a superconductive wire on the seed layer. The superconductive wire is a metal nitride different from the metal nitride of the seed layer and is optically coupled to the optical waveguide.

The photomultiplier includes a set of macrocells, each comprising at least two microcells, each being connected to an output node according to an OR diagram, and achieving great energy efficiency upon deactivating each of the microcells when these are activated almost simultaneously, and that otherwise would have been masked by the OR diagram. To this end, each of the microcells comprises an active quenching and recharge circuit; an avalanche diode; a first deactivation transistor with its gate connected to an external processor, and its drain and source associated with the active quenching and recharge circuit; a second deactivation transistor with its gate connected to an external processor, and its source associated with the active quenching and recharge circuit.

An optical energy detector and a method for detecting a broad range of optical energy are disclosed. The detector comprising a superconducting nanowire filament on a substrate, an electrical current pulse source, a laser pulse source, a first pickup probe, and a second pickup probe for measuring the voltage across the filament. The filament is maintained below a supercomputing critical temperature. The filament is biased with an electrical current pulses slight below the critical current of the filament which creates nonequilibrium state. The filament is excited by the laser pulses, and as a result, a voltage appears after a delay time. The voltage is measured for determining the amount of the optical energy. A reference curve of the voltage and the corresponding delay time can be used for calibrating any light source.

A method of fluorescence spectroscopy includes providing a high-performance sensor that combines imaging with high intrinsic time resolution and high-rate capability, and resolving fluorescence data in four dimensions.

[Problem to be Solved]

Provided is a fluorescence measuring device that suppresses or eliminates fluctuations in a light source, problems of jitter associated with signal processing, and the influence of background light and performs highly sensitive and accurate quantification even when it is difficult to separate fluorescence from scattered light due to time difference or wavelength difference.

[Solution] The fluorescence measuring device includes a continuous light source 2, an excitation light irradiation unit 3, an excitation light intensity detection unit 4, a photon counting type fluorescence detection unit 5, a rectangular wave modulation circuit 6 of the continuous light source, a timing circuit 7 that generates a rectangular wave pulse to be supplied to the rectangular wave modulation circuit and a gate pulse for signal processing, a gate counter circuit 8 that counts fluorescence photon pulse signals during the gate pulse period, a physical parameter information acquisition unit 9, and a concentration calculator 10. By digitally processing digital signals with this configuration and accurately digitally calculating and subtracting the current background photon count conversion value, it is possible to perform highly sensitive and highly accurate quantification by appropriately removing the influence of the background.