An otoscope uses differential reflected response of optical energy at an absorption range and an adjacent wavelength range to determine the presence of water (where the wavelengths are water absorption wavelength and adjacent non-absorption excitation wavelengths). In another example of the invention, the otoscope utilizes OCT in combination with absorption and non-absorption range for bacteria and water.

There is described an infrared spectrometer having an optical circuit which comprises one or more hollow waveguides provided by elongate channels formed in a substrate. The optical circuit is arranged such that infrared light in the optical circuit acquires one or more spectral properties for detection by the spectrometer. A laser source couples laser light into an input hollow waveguide portion of the optical circuit, and an optical detector receives the light from an output hollow waveguide portion of the optical circuit, so that an analyser can determine said one or more spectral properties from the detected light.

A new spectral measurement technique is provided which enables measurement even if the light to be measured exists for a very short period. In one embodiment, a broadband pulsed light wave whose wavelength shifts temporally and continuously in a pulse interferes with a light wave to be measured. The intensity at each wavelength of the light wave to be measured is obtained using a Fourier transform of the output signal from a detector that has detected the intensity of the wave resulting from the interference. A laser beam from a laser source is converted to a supercontinuum wave by a nonlinear optical element, and a pulse extension element extends pulses of the supercontinuum wave, thus generating the broadband pulsed light wave.

Raman spectroscopy data is collected using a Spatial Heterodyne Spectrometer and processed in order to reduce signal noise. The processing of the Raman spectroscopy data includes segmenting generating an interferogram from the Raman spectroscopy data, segmenting the interferogram, determining an estimate of power spectrum density, and averaging the estimates of power spectrum density for each segment to provide an output spectrum. The output spectrum has greatly reduced variance of the individual power measurements, and allows the length of segments to be optimized to balance noise reduction operations and the loss of frequency resolution.

A combining light emitted from a measurement point of an object to be measured into one parallel light beam by combining optical system; dividing, by phase shifter, parallel light beam emitted from combining optical system into first and second light beam, emitting first and second light beam toward light-receiving face while providing an optical path length difference between the first and second light beam, and causing the first and second light beam to planarly enter the light-receiving face so that at least a part of an incident region of first light beam on the light-receiving face and at least a part of an incident region of second light beam overlap with each other; and obtaining an interferogram at measurement point based on intensity distribution of light in a region where an incident region of the first and second light beam on light-receiving face overlap, and acquiring spectrum by Fourier-transforming interferogram.

Fourier Transformation Spectrometer, FT Spectrometer, comprising: Michelson-Type Interferometer (601, 602, 603, 604, 605, 606, 607, 608, 609) comprising: at least one beam splitter unit designed to split an incident light beam (EB) of a spatially expanded object into a first partial beam (TB1) and a second partial beam (TB2); and for at least partially overlaying the first partial beam (TB1) and the second partial beam (TB2) with a lateral shear (s); a first beam deflection unit designed to deflect the first partial beam (TB1) at least once; a second beam deflection unit designed to deflect the second partial beam (TB2) at least once; wherein at least one among the first beam deflection unit and the second beam deflection unit represents a (2n+1) periscope group with (2n+1) mirror surfaces, and all (2n+1) mirror surfaces are arranged vertically in relation to a common reference plane, in order to respectively deflect the first partial beam (TB1) and/or the second partial beam (TB2) (2n+1) times, and wherein the (2n+1)-fold deflection generates the lateral shear (s) between the first partial beam (TB1) and the second partial beam (TB2), and wherein n is a natural number ≥1.

An optical coherence tomography (OCT) engine includes a digital Fourier-Transform (dFT) spectrometer, a tunable delay line, and a high-speed optical phased array (OPA) scanner integrated onto a single chip. The broadband dFT spectrometer offers superior signal-to-noise ratio (SNR) and fine axial resolution; the tunable delay line ensures large imaging depth by circumventing sensitivity roll-off; and the OPA can scan the beams at GHz rates without moving parts. Unlike conventional spectrometers, the dFT spectrometer employs an optical switch network to retrieve spectral information in an exponentially scaling fashion—its performance doubles with every new optical switch added to the network. Moreover, it also benefits from the Fellgett's advantage, which provide a significant SNR edge over conventional spectrometers. The tunable delay line balances the path length difference between the reference and sample arms, avoiding any need to sample high-frequency spectral fringes.

Systems and methods which provide a high-throughput point source light coupling structure implementing a condenser configured according to one or more condenser configuration rules are described. Embodiments of a high-throughput point source light coupling structure utilize a birefringent plate configuration in combination with a condenser and point source to provide a light coupler structure for a birefringent-static-Fourier transform interferometer implementation. According to some examples, the optical axis of a first and second birefringent plate of a birefringent plate configuration are not in the same plane. A condenser of a high-throughput point source light coupling structure of embodiments is provided in a defined (e.g., spaced, relational, etc.) relationship with respect to the point source and/or a camera lens used in capturing an interference pattern generated by the light coupling structure. High-throughput point source light coupling structures herein may be provided as external accessories for processor-based mobile devices having image capturing capabilities.

A waveguide spectrometer includes at least one substrate layer with at least one surface waveguide extending from an inlet face to guide the received light; at least one evanescent field sampler in the waveguide to out-couple light along the waveguide; at least one light sensing unit to detect the out-coupled light, each electrically connected to an electronic read out system; and means to achieve counter propagating optical signals inside the waveguide to obtain interference between the counter propagating optical signals generating an interference pattern along the waveguide. A compact and simple construction with improved spectral range/bandwidth of the spectrometer can be achieved with at least one modulator integrated into the sampling waveguide structure to enable conditioning of the guided optical signals and for changing the refractive index. The integrated modulator is realized by electrodes placed aside directly neighboured to the guiding core resp. waveguide generating an optical phases shift required for scanning the interferogram.

Compact optical spectrometers are provided to measure optical spectral composition of light.