A light detection module has N optical channels, each with an optical filter, a detector, and an amplifier; and an N?1 switch with N input ports each connected to one corresponding output port of each channel to receive an amplified detector output corresponding to a filtered optical intensity incident on that detector. The switch cycles between channels, connecting each amplified detector output in turn to the output port. An ADC samples a time dependent optical intensity signal from the switch, generating a corresponding ADC digital signal output. A microcontroller, connected to the N?1 switch and the ADC, controls acquisition by the ADC to provide a digital voltage data stream from each channel; making the average optical intensity value characterizing the voltage data stream available from each channel at a digital output port of the microcontroller, as N data values, characterizing the light incident on the N channels of the module.

A spectroscopic system may include: a probe having a probe tip and an optical coupler, the optical coupler including an emitting fiber group and first and second receiving fiber groups, each fiber group having a first end and a second end, wherein the first ends of the fiber groups are formed into a bundle and optically exposed through the probe tip; a light source optically coupled to the second end of the emitting fiber group, the light source emitting light in at least a first waveband and a second waveband, the second waveband being different from the first waveband; a first spectrometer optically coupled to the second end of the first receiving fiber group and configured to process light in the first waveband; and a second spectrometer optically coupled to the second end of the second receiving fiber group and configured to process light in the second waveband.

In a method for the spectrally resolved measurement of optical properties of samples, a sample is arranged at a measurement position, and light is generated using a light source. Spectral components of the light are transmitted as excitation light in a first optical path to the sample. Light that has been emitted or transmitted by the sample is transmitted in a second optical path to a detector. A tunable monochromator is arranged in the first optical path and/or in the second optical path. A spectrum of the emitted or transmitted light is recorded over an effective spectral range by shifting a spectral passage range of the tunable monochromator. The method is characterized in that light in the form of light pulses with a specifiable pulse frequency is used. The spectral passage range of the tunable monochromator is shifted at a shifting speed continuously from an initial wavelength to an end wavelength for recording a spectrum. The pulse frequency of the light is synchronized with the shifting speed of the spectral passage range by way of a control such that a plurality of measurements of the emitted or transmitted light takes place within the effective spectral range at a corresponding plurality of spectral support points.

A fiber grating demodulation system for enhancing spectral resolution by finely adjusting an imaging focus mirror, includes a laser pump source, a wavelength division multiplexer, a fiber Bragg grating, a diaphragm, a slit, a collimating mirror, a light splitting grating, an imaging focus mirror, a linear array detector. The laser pump source, the wavelength division multiplexer, the fiber Bragg grating are connected in sequence, the wavelength division multiplexer is connected to the diaphragm. Light emitted from the laser pump source is multiplexed by the wavelength division multiplexer and then enters the fiber Bragg grating, a reflection spectrum of the fiber Bragg grating enters the slit of the fiber grating demodulation system as injected light. After passing through the slit, the injected light is reflected by the collimating mirror, the light splitting grating, and the imaging focus mirror in sequence, and is finally converged to the linear array detector.

A fiber grating demodulation system for enhancing spectral resolution by finely adjusting an imaging focus mirror, includes a laser pump source, a wavelength division multiplexer, a fiber Bragg grating, a diaphragm, a slit, a collimating mirror, a light splitting grating, an imaging focus mirror, a linear array detector. The laser pump source, the wavelength division multiplexer, the fiber Bragg grating are connected in sequence, the wavelength division multiplexer is connected to the diaphragm. Light emitted from the laser pump source is multiplexed by the wavelength division multiplexer and then enters the fiber Bragg grating, a reflection spectrum of the fiber Bragg grating enters the slit of the fiber grating demodulation system as injected light. After passing through the slit, the injected light is reflected by the collimating mirror, the light splitting grating, and the imaging focus mirror in sequence, and is finally converged to the linear array detector.

A spectral imaging device includes an imager, a scanning stage to establish relative motion between the imager and a sample in a scanning direction and an optical system controlling a light characteristic of a light beam constituting an image of the sample to the imager. The optical system includes a light varying element to receive the light beam and provide an output light beam with spatially varying light characteristic over a cross-section thereof. A set of redirecting optical elements direct light rays from the sample to form the light beam, and to focus the output light beam onto the imager. A controller controls the scanning stage and the imager to capture a plurality of image frames with an overlap including a defined shift that is greater than 1 pixel along the scanning direction between consecutive image frames. A computing device consolidates image data to provide an image of the sample.

A spectral imaging device includes an imager, a scanning stage to establish relative motion between the imager and a sample in a scanning direction and an optical system controlling a light characteristic of a light beam constituting an image of the sample to the imager. The optical system includes a light varying element to receive the light beam and provide an output light beam with spatially varying light characteristic over a cross-section thereof. A set of redirecting optical elements direct light rays from the sample to form the light beam, and to focus the output light beam onto the imager. A controller controls the scanning stage and the imager to capture a plurality of image frames with an overlap including a defined shift that is greater than 1 pixel along the scanning direction between consecutive image frames. A computing device consolidates image data to provide an image of the sample.

A light detection module has N optical channels, each with an optical filter, a detector, and an amplifier; and an N1 switch with N input ports each connected to one corresponding output port of each channel to receive an amplified detector output corresponding to a filtered optical intensity incident on that detector. The switch cycles between channels, connecting each amplified detector output in turn to the output port. An ADC samples a time dependent optical intensity signal from the switch, generating a corresponding ADC digital signal output. A microcontroller, connected to the N1 switch and the ADC, controls acquisition by the ADC to provide a digital voltage data stream from each channel; making the average optical intensity value characterizing the voltage data stream available from each channel at a digital output port of the microcontroller, as N data values, characterizing the light incident on the N channels of the module.

A vehicle contains a light-detection module that operates to capture and analyze light emitted from a plurality of sources on the surface of the Earth, while the vehicle is flying above the surface of the Earth. The light detection module is operatively coupled to a processing module with access to a data bank module comprising optical emission spectra data values and flicker spectra data values characteristic of two or more artificial illumination source present on the surface of the Earth. In some cases, the vehicle may, for example, be a satellite, a drone, an airplane, or a balloon.