A measurement device characterizes an environment. The measurement device includes a transmitter and a receiver. The transmitter transmits a transmitted light. The transmitter includes an atomically two-dimensional material for emitting the transmitted light. The atomically two-dimensional material is tunable to select a predominate wavelength of the transmitted light within a tunable range of wavelengths. The receiver receives a received light, which is the transmitted light after encountering the environment. The receiver characterizes the environment from a measured change between the received light and the transmitted light.

An imaging system, such as a surgical microscope, laparoscope, or endoscope or integrated with these devices, includes an illuminator providing patterned white light and/or fluorescent stimulus light. The system receives and images light hyperspectrally, in embodiments using a hyperspectral imaging array, and/or using narrowband tunable filters for passing filtered received light to an imager. Embodiments may construct a 3-D surface model from stereo images, and will estimate optical properties of the target using images taken in patterned light or using other approximations obtained from white light exposures. Hyperspectral images taken under stimulus light are displayed as fluorescent images, and corrected for optical properties of tissue to provide quantitative maps of fluorophore concentration. Spectral information from hyperspectral images is processed to provide depth of fluorophore below the tissue surface. Quantitative images of fluorescence at depth are also prepared. The images are displayed to a surgeon for use in surgery.

A system is described that combines spectropolarimetry with scatterometry. The system uses an annular mirror and liquid crystal devices to control the angle of the incident light cone, the polarization and wavelength, an imaging setup and one or more video cameras so that spectroseopic-polarimetric-scatterometric images can be grabbed rapidly. The system is also designed to incorporate additional imaging modes such as interference, phase contrast, fluorescence and Raman spectropolarimetric imaging.

A spectrometer includes an emitter that is configured to emit electromagnetic radiation, a sample area that is arranged at an outer face of the spectrometer, a modulation unit including an electrochromic material, an optical filter, an optical detector, an integrated circuit that has a main plane of extension, and an optical path for electromagnetic radiation emitted by the emitter towards the optical detector via the sample area, the modulation unit and the optical filter, wherein the electrochromic material is electrically connected with the integrated circuit, and the modulation unit is configured to modulate electromagnetic radiation temporally. Furthermore, a method for detecting electromagnetic radiation is provided.

An optical spectrum analyzer (OSA) for measuring an optical spectrum of an input optical signal in a measurement wavelength range is provided. The OSA comprises a modulator, an integrated optical filter, and a photodetector. The modulator modulates the input optical signal by applying a dither modulation to facilitate detection and noise rejection. The integrated optical filter, which may include a ring resonator system, is sequentially tunable to selectively transmit each wavelength of the modulated optical signal in the measurement wavelength range. The photodetector sequentially detects each wavelength of the modulated optical signal in the measurement wavelength range to provide a representative output electrical signal.

A spectroscope device is provided to maintain the uniformity of the central transmitting wavelength in the field of view and to minimize the broaden of the bandwidth of the transmitting wavelengths in an optical lens using an optical tunable filter (variable wavelength filter), even with a wide field of view and/or a large numerical aperture. A space is defined in which, when each beam that is incident from each off-axial object point on the object surface toward the optical lens that includes a plurality of lens elements between an object surface and a conjugate real image surface reaches the optical tunable filter, the chief ray is maintained parallel to the optical axis. Therefore, if an optical tunable filter is disposed in this space, each beam is always incident normal to the filter, so only the narrow band components at the specific central wavelength can be transmitted.

A method of operating a hyperspectral imaging device includes receiving a light beam at a liquid crystal retarding device, and driving the liquid crystal retarding device with a pre-computed voltage waveform, wherein the voltage waveform is selected to reach a target optical retardance over time for the liquid crystal retarding device.

A light modulation device and a single-channel spectrum detection system are provided. The light modulation device includes: a light guide plate; a dispersing component configured to disperse received light into light of different wavelengths and to diffract the light of different wavelengths into the light guide plate at different angles; and a dynamic filtering component configured to prevent light of a selected wavelength in the light guide plate from entering the dynamic filtering component such that the light of the selected wavelength emits out from the light guide plate, and to make light of non-selected wavelengths in the light guide plate enter the dynamic filtering component such that the light of the non-selected wavelengths is filtered out from the light guide plate.

A system and method for analyzing a sample using Raman spectral light includes a light source, a light detector, a narrow band pass filter and an analyzer. Within the system, excitation light is directed to interrogate the sample. The narrow band pass filter is positioned to receive Raman scattered light produced as a result of the interrogation. The light detector is positioned to receive the Raman scattered light that has passed through the at least one narrow band pass filter. The analyzer contains stored instructions that when executed cause the processor to a) control the light source; and b) process signals produced by the light detector to analyze the sample material, the signals representative of the intensity of the Raman scattered light received by the at least one light detector corresponding to one or more wavenumbers in a high wavenumber region of a Raman signal.

The present disclosure provides an approximation-free and iteration-free method for spectral analysis of an intracavity electro-optic modulation type optical frequency comb, a device and a medium. The method includes: calculating a residual phase delay of a single propagation of laser in a resonant cavity, analyzing outgoing transmission characteristics of a light source of the intracavity electro-optic modulation type optical frequency comb, accumulating laser electric field intensities corresponding to all cyclic propagation times n to obtain an outgoing laser electric field intensity E, obtaining a new approximate-free outgoing laser electric field intensity E′ of the intracavity electro-optic modulation type optical frequency comb, obtaining an outgoing laser electric field intensity E.sub.k′ of k.sup.th-order comb teeth, calculating an outgoing laser light intensity I.sub.k of the k.sup.th-order comb teeth and accurately analyzing a spectrum of the intracavity electro-optic modulation type optical frequency comb, determining a working state according to a simulated spectral envelope curve, and guiding the subsequent optimization design and debugging. The method for the spectral analysis of the optical frequency comb is higher in accuracy without approximation and faster in speed without iteration, and can analyze the spectrum of the intracavity electro-optic modulation type optical frequency comb according to any known working mode.