According to the present disclosure, techniques related to manufacturing and applications of power photodiode structures and devices based on group-III metal nitride and gallium-based substrates are provided. More specifically, embodiments of the disclosure include techniques for fabricating photodiode devices comprising one or more of GaN, AlN, InN, InGaN, AlGaN, and AlInGaN, structures and devices. Such structures or devices can be used for a variety of applications including optoelectronic devices, photodiodes, power-over-fiber receivers, and others.

A mode control system and method for controlling an output mode of a broadband radiation source including a photonic crystal fiber (PCF). The mode control system includes at least one detection unit configured to measure one or more parameters of radiation emitted from the broadband radiation source to generate measurement data, and a processing unit configured to evaluate mode purity of the radiation emitted from the broadband radiation source, from the measurement data. Based on the evaluation, the mode control system is configured to generate a control signal for optimization of one or more pump coupling conditions of the broadband radiation source. The one or more pump coupling conditions relate to the coupling of a pump laser beam with respect to a fiber core of the photonic crystal fiber.

A non-power-driven photometer is provided, the photometer comprising: a body; and multiple narrow angle photoreceivers (narrow angle probes) formed in the body, wherein the multiple narrow angle probes receive light in the atmosphere, which is incident over a range of different azimuth angles, and allow the characteristics of the atmosphere to be analyzed with reference to the relationship between the received light and the azimuth angle of the narrow angle probe corresponding to the received light. According to the present invention, since the photometer is driven without being supplied with power, light intensity measurement can be performed in a short time. Further, since light intensity measurement can be performed with no movement or only a short-distance movement of a vehicle or airplane equipped with the photometer, the problem of errors caused by differences in the time and location of measurement can be prevented.

The invention relates to a light module including a laser source capable of emitting a coherent light beam of given wavelength, a first sensor capable of picking up a first light signal of a wavelength lying in a first band of wavelengths centered around the given wavelength and a second sensor capable of picking up a second light signal of a wavelength lying in a second band of wavelengths centered around a wavelength distinct from the given wavelength. In particular, the light module includes a detection module capable of comparing at least one value that is a function of the signals to a threshold value and of commanding the stopping of the laser source as a function of the comparison.

A photon detection device, configured to couple to a multicore optical fibre, the device comprising a plurality of detection regions, each detection region being arranged to align with just a single core of the multicore optical fibre when the device is coupled to the multicore optical fibre.

A system provides light received from NV diamond material to an optical collector. The provision of light received from NV diamond material to an optical collector impacts the efficiency by which light is directed to the optical collector. The system may be employed to efficiently direct light from the NV diamond material to the optical collector.

A polarimetry apparatus comprising a plurality of flexible light conduits each having first and second ends, and a respective polarization modulator associated with each light conduit, wherein each light conduit is configured to receive incident light from a different predetermined region in space via the first end, and deliver said light to a detector unit via the second end, and wherein the polarization modulator is configured to modulate the polarization of the light to enable a partial or complete polarization state of the incident light to be determined by the detector unit for each light conduit.

The present invention provides methods and systems for measuring optical power that require neither alterations to the optical fiber nor physical contact with the optical fiber, the system including an optical fiber configured to propagate an optical signal, wherein the optical fiber includes a core and at least a first cladding layer, wherein a portion of the optical signal scatters out of the optical fiber along a length of the optical fiber to form scattered fiber light; a detector system configured to receive the scattered fiber light along the length of the optical fiber and to output a detection signal based on the received scattered fiber light; and a processor configured to receive the detection signal and to determine a power value of the optical signal based on the received detection signal.

According to one implementation, an optical observation system includes an optical fiber and at least one detection system. The optical fiber has at least one curved portion as a sensor for inputting light which has occurred in a test region. The optical fiber inputs the light from the at least one curved portion and transmits the light. The at least one detection system detects the light transmitted by the optical fiber. Further, according to one implementation, an optical observation method includes: inputting light, which has occurred in a test region, from at least one curved portion of an optical fiber and transmitting the light; and detecting the light transmitted by the optical fiber.

An optical sensor and an electronic device having an optical sensor. The optical sensor includes: an optical waveguide containing a photochromic material; a light emitter that emits visible light to be incident on the optical waveguide; and a light receiver that detects the visible light emitted from the light emitter and progressing through the optical waveguide. A transmittance of the optical waveguide in relation to the visible light may be changed by the photochromic material as the optical waveguide is exposed to UV light. The optical sensor and the electronic device having the same may be variously implemented according to exemplary embodiments.