Improved optical coherence tomography systems and methods to measure retinal data are presented. The systems may be compact, provide in-home monitoring, and have automation to allow the patient to measure himself or herself.

Systems, methods, and computer readable medium are provided for determining interferometric data and spectral data associated with combustion conditions of a flame in a combustion chamber using a sensor head including a first vacuum cavity, a diaphragm operatively interfaced to an inner portion of the combustion chamber, and an optical sensor interrogator configured on a computing device and coupled to the sensor head via optical fibers. The optical sensor interrogator including an interferometer configured to determine interferometric data associated with the flame based on light transmitted and reflected via a first optical fiber and a spectrometer configured to determine spectral data associated with the flame based on light transmitted via a second optical fiber.

The invention relates to the fields of optical technologies and telecommunication technologies, and is dedicated to determination of the direction of optical beam in free-space optical communication systems. The invention is based on the property of interference optical filters (IOF), that transmittance and reflectance of such filters, for a beam with given optical spectrum, depends on the angle of the beam with respect to IOF surface normal. According to the proposed method, at least one IOF is used, which is rotated by defined angle with respect to the optical axis of the detection device. In the implementation of the detection device with one IOF (4), two optical power detectors (6, 7) are used, which measure optical power of the beam reflected from the IOF (1′) and transmitted through the IOF (1″). Based on these measurements, the angle of the beam, with respect to the optical axis (5) of the device, is determined in one plane. To determine beam angle in another (perpendicular) plane, second beam angle detection device is used, which has IOF rotated in the perpendicular plane. After determining beam angles in both mutually perpendicular planes, full information regarding beam direction with respect of the optical axis of the system is acquired.

An optical sensor system including a semiconductor substrate; a self-mixing interferometry (SMI) sensor formed on the semiconductor substrate and including a semiconductor laser having a resonant cavity; and an array of photodetectors formed on the semiconductor substrate. The SMI sensor is configured to generate an SMI signal responsive to a retro-reflection of electromagnetic radiation emitted by the semiconductor laser and received into the resonant cavity. The array of photodetectors is configured to generate a set of angular-resolved scatter signals responsive to a scatter of the electromagnetic radiation emitted by the semiconductor laser.

Embodiments of systems and methods for measuring a surface topography of a semiconductor chip are disclosed. In an example, a method for measuring a surface topography of a semiconductor chip is disclosed. A plurality of interference signals each corresponding to a respective one of a plurality of positions on a surface of the semiconductor chip are received by at least one processor. The interference signals are classified by the at least one processor into a plurality of categories using a model. Each of the categories corresponds to a region having a same material on the surface of the semiconductor chip. A surface height offset between a surface baseline and at least one of the categories is determined by the at least one processor based, at least in part, on a calibration signal associated with the region corresponding to the at least one of the categories. The surface topography of the semiconductor chip is characterized by the at least one processor based, at least in part, on the surface height offset and the interference signals.

An optical sensor system including a semiconductor substrate; a self-mixing interferometry (SMI) sensor formed on the semiconductor substrate and including a semiconductor laser having a resonant cavity; and an array of photodetectors formed on the semiconductor substrate. The SMI sensor is configured to generate an SMI signal responsive to a retro-reflection of electromagnetic radiation emitted by the semiconductor laser and received into the resonant cavity. The array of photodetectors is configured to generate a set of angular-resolved scatter signals responsive to a scatter of the electromagnetic radiation emitted by the semiconductor laser.

A detection device adapted to detect lens surface and a stitching interferometer including the same are disclosed. The detection device includes: a cylindrical detection frame comprising support bosses arranged on an inner wall of the detection frame in a circumferential direction of the detection frame, the lens to be detected being placed on the support bosses; and a plurality of support units mounted at a bottom of the detection frame in the circumferential direction of the detection frame, each of the support units comprising: a support mechanism configured to be movable in an axial direction of the detection frame and cooperate with the support bosses so as to support the lens to be detected together; and a balance mechanism configured to provide a balancing force for balancing with force of the support mechanism for supporting the lens to be detected, so that axial support force of each supporting unit for the lens to be detected is equal to axial support force of each support boss for the lens to be detected in both cases where the axial direction of the detection frame is parallel to a gravity direction of the lens to be detected and inclined with respect to the gravity direction of the lens to be detected.

Embodiments of systems and methods for measuring a surface topography of a semiconductor structure are disclosed. In certain examples, a plurality of interference signals, each corresponding to a respective one of a plurality of positions on a surface of the semiconductor structure, are measured. Calibration signals, associated with a baseline region corresponding to a first category of a plurality of categories and a calibrated region corresponding to a second category of the plurality of categories, are measured. A surface height offset, associated with the baseline region and the calibrated region, is determined based on original surface heights and the calibration signals. The original surface heights are determined based on the plurality of interference signals corresponding to the baseline region and the calibrated region. The surface topography of the semiconductor structure is characterized based, at least in part, on the surface height offset and the original surface heights.

Various disclosed embodiments provide illustrative interferometers, optical phase locked loops, laser systems, interferometry methods, and phase locked loop methods. In illustrative embodiments, light from a laser is split into a first arm and a second arm. Light in an arm chosen from the first arm and the second arm is time delayed. The light in the first arm is split into third, fourth, and fifth arms. The light in the second arm is split into sixth, seventh, and eighth arms. Light in the seventh and eighth arms is phase shifted relative to light in the sixth arm. Light in the third, fourth, and fifth arms is combined with light in the sixth arm and phase shifted light in the seventh and eighth arms, respectively. A frequency correction signal for the laser is generated.

Exemplary systems, devices, methods, apparatus and computer-accessible media for providing and/or utilizing optical frequency domain imaging (OFDI) and fluorescence of structures and, e.g., multimodality imaging using OFDI techniques and fluorescence imaging techniques are described. For example, an arrangement can provide at least one electro-magnetic radiation to an anatomical structure. Such exemplary arrangement can include at least one optical core and at least one cladding at least partially surrounding the fiber(s). A region between the optical core(s) and the cladding(s) can have an index that is different from indexes of the optical core(s) and the cladding(s). The arrangement can also include at least one apparatus which is configured to transmit the radiation(s) via the optical core(s) and the cladding(s) to the anatomical structure.