Technologies are generally described for spectroscopic determination of one or more optical properties of a gemstone. An imaging device may include one or more light sources configured to illuminate one or more portions of the gemstone, and one or more photo detectors configured to detect reflected light from the portions of the gemstone in response to the illumination. An analysis module may be communicatively coupled to the imaging device, and configured to analyze the reflected light to determine the optical properties of the portions of the gemstone. The optical properties may include at least one of a clarity, color, fluorescence, birefringence, dichroism, and brilliance of the portions of the gemstone. In some examples, an optical fingerprint of the gemstone may be created based on one or more determined optical characteristics of the portions of the gemstone, where the optical fingerprint may uniquely identify the gemstone.

A measurement system is provided with an array of laser diodes with one or more Bragg reflectors. At least a portion of the light generated by the array is configured to penetrate tissue comprising skin. A detection system configured to: measure a phase shift, and a time-of-flight, of at least a portion of the light from the array of laser diodes reflected from the tissue relative to the portion of the light generated by the array; generate one or more images of the tissue; detect oxy- or deoxy-hemoglobin in the tissue; non-invasively measure blood in blood vessels within or below a dermis layer within the skin; measure one or more physiological parameters based at least in part on the non-invasively measured blood; and measure a variation in the blood or physiological parameter over a period of time.

An active remote sensing system is provided with an array of laser diodes that generate light directed to an object having one or more optical wavelengths that include at least one near-infrared wavelength between 600 nanometers and 1000 nanometers. One of the laser diodes pulses at a modulation frequency between 10 Megahertz and 1 Gigahertz and has a phase associated with the modulation frequency. A detection system includes a photo-detector, a lens, a spectral filter at an input to the photo-detector, and a processor that processes digitized signals received from the photo-detector to generate an output signal. The detection system uses a lock-in technique that synchronizes pulsing the one laser diode. The active remote sensing system is configured to be mounted on a vehicle or an airborne platform to provide distance information based on a time-of-flight measurement.

A Raman spectroscopy system is provided. The spectroscopy system includes an optical switch including a pump inlet, a return outlet, a plurality of pump outlets, and a plurality of return inlets. The spectroscopy system includes a plurality of radiation sources optically coupled to the pump inlet of the optical switch, and a detector optically coupled to the return outlet of the optical switch. The spectroscopy system further includes a plurality of probes, each probe optically connected to at least one of the plurality of pump outlets of the optical switch by at least one excitation fiber and optically coupled to one of the return inlets of the optical switch by at least one emission fiber.

Systems for measuring optical properties of a specimen are disclosed. The systems are configured to sample signals related to the measurement of the properties of a specimen, and perform software-based coherent detection of the signals to generate resulting measurements are based on the signals acquired at substantially the same time instance. This facilitates the displaying or generating of the desired measurements in real time. In one configuration, the system is configured to direct a modulated light signal at a selected wavelength incident upon a specimen. In another configuration, the system is configured to direct a combined light signal, derived from a plurality of light signals at different wavelengths and modulated with different frequencies, incident upon a specimen. In yet another configuration, the system is configured to direct a plurality of light signals modulated with different frequencies incident upon different regions of a specimen.

An optical module 1 includes: a mirror unit 2 including a base 21, a movable mirror 22, and a fixed mirror 16; a beam splitter unit 3 that is disposed on one side of the mirror unit 2 in a Z-axis direction; a light incident unit 4 that causes measurement light L0 to be incident to the beam splitter unit 3; a first light detector 6 that is disposed on the one side of the beam splitter unit 3 in the Z-axis direction, and detects interference light L1 of measurement light which is emitted from the beam splitter unit 3; a support 9 to which the mirror unit 2 is attached; a first support structure 11 that supports the beam splitter unit 3; and a second support structure 12 that is attached to the support 9 and supports the first light detector 6.

An example system includes a light source, a first spectrometer, a second spectrometer, and an electronic control module. The light source is operable to emit light within a first range of wavelengths in a field of illumination. The first spectrometer is operable to measure first sample light reflected from an object within a second range of wavelengths and in a first field of detection. The second spectrometer is operable to measure second sample light reflected from the object within a third range of wavelengths and in a second field of detection. The electronic control module operable to determine, based on the measured first sample light and the measured second sample light, a distance between the system and the object, and determine, based on the measured first sample light and the measured second sample light, a spectral distribution of light corresponding to the object.

Apparatus and methods are described for use with feces of a subject that are disposed within a toilet bowl, and an output device. One or more light sensors are configured to receive light from the toilet bowl, while the feces are disposed within the toilet bowl. A computer processor analyzes the received light, and, in response thereto, detects a currently-occurring inflammatory bowel disease episode, and/or a predicted upcoming inflammatory bowel disease episode. The computer processor generates an output on the output device, at least partially in response thereto. Other applications are also described.

An apparatus for measuring a spectrum includes a light source array configured to emit light towards an object, a photodetector configured to detect light reflected by the object; and a processor configured to measure, using the light source array and the photodetector, a plurality of temperature correction spectra based on a temperature change of the light source array, obtain a light source temperature drift vector by analyzing the measured plurality of temperature correction spectra, measure, using the light source array and the photodetector, an analysis spectrum by using the light source array and the photodetector, and adjust the measured analysis spectrum to reduce an effect of the temperature change of the light source array by using the obtained light source temperature drift vector.

A Skin Tanning Measuring Device is provided to determine tanning level and skin penetration to various wavelengths, comprising of a device capable to inject light into the skin and monitor the light level emerging out from the skin tissue at a different location. By measuring the amount of emerging light, an individual tanning level could be deducted based on at least one additional measurement performed at an untanned location. The measurements will be used to compare between those levels and the saturated tanning levels, and will issue out a warning when the tanning is too high and additional exposure may be hazardous. Moreover, the offered system will measure skin penetration to UV hazardous radiation with and without sunscreen protection. The device will also provide information regarding melanin absorption as a function of UV exposure, and monitor those values over time and issue out a warning to users.