A tunable spectral filter includes a first tunable dispersive element, a first optical element, a spatial filtering element located at the focal plane, a second optical element, and a second dispersive element. The first tunable dispersive element introduces spectral dispersion to an illumination beam with an adjustable dispersion. The first optical element focuses the illumination beam at a focal plane in which a distribution of a spectrum of the spectrally-dispersed illumination beam at the focal plane is controllable by adjusting the dispersion of the first tunable dispersive element. The spatial filtering element filters the spectrum of the illumination beam based on the distribution of the spectrum of the illumination beam at the focal plane. The second optical element collects the spectrally-dispersed illumination beam transmitted from the spatial filtering element. The second tunable dispersive element removes the dispersion introduced by the first tunable dispersive element from the illumination beam.

A spectral measurement device includes a light reflection grating having a plurality of movable gratings and a movable grating drive unit that displaces the movable gratings to alter a grating pattern of the light reflection grating, a light detecting element that detects light incident on the light reflection grating, a storage unit storing a relationship between a light quantity to be detected by the light detecting element and corresponding light intensities at differing wavelengths for different grating patterns, and a computation unit that calculates light intensities at the differing wavelengths of the light incident on the light reflection grating based on the light quantity of the incident light detected by the light detecting element for each of the different grating patterns by altering the grating pattern based on the relationship between the light quantity and the corresponding light intensities for the different grating patterns stored in the storage unit.

A method comprises obtaining reference data about a 3D calibration object, the reference data comprising known coordinates for a plurality of points on the object, and obtaining measurement data comprising measurements for the plurality of points on the object, the measurement data having been generated based on scanning of the object by an uncalibrated intraoral scanner. The method comprises comparing the measurement data to the reference data to determine differences therebetween and applying the determined differences between the measurement data and the reference data for the plurality of points to a function to generate a compensation model that compensates for one or more inaccuracies of the intraoral scanner. The compensation model is then stored, wherein the compensation model causes the intraoral scanner to be a calibrated intraoral scanner and is usable to correct measurement errors of the intraoral scanner caused by the one or more inaccuracies of the intraoral scanner.

A fluid medium monitoring apparatus of the present invention comprises: a light source unit for irradiating light; a first collimator unit for collimating light irradiated from the light source unit; a flow cell unit in which a fluid medium flows and light is allowed to absorb the wavelength of the fluid medium while proceeding along the moving direction of the fluid medium; and a light detection unit for detecting the wavelength of the light passing through the flow cell unit.

An optical system operating in the near or short-wave infrared wavelength range identifies an object based on water absorption. The system comprises a light source with modulated light emitting diodes operating at wavelengths near 1090 and 1440 nanometers, corresponding to lower and higher water absorption. The system further comprises one or more wavelength selective filters and a housing that is further coupled to an electrical circuit and a processor. The detection system comprises photodetectors that are synchronized to the light source, and the detection system receives at least a portion of light reflected from the object. The system is configured to identify the object by comparing the reflected light at the first and second wavelength to generate an output value, and then comparing the output value to a threshold. The optical system may be further coupled to a wearable device or a remote sensing system with a time-of-flight sensor.

A printer includes a spectroscope and a carriage moving unit. The spectroscope includes a wavelength-selective interference filter on which light from a measurement target is incident, and the carriage moving unit moves the spectroscope in an X direction with respect to the measurement target. If the measurement target is a color patch, the spectroscope performs spectrometry by changing a wavelength of light passing through the wavelength-selective interference filter in a first period during which the spectroscope is moved in the X direction, and passes light of an initial wavelength through the wavelength-selective interference filter at a start of measurement and at an end of measurement in the first period. A first output value that is a measured value from the spectrometry at the start of measurement is compared with a second output value that is a measured value from the spectrometry at the end of measurement.

A printer includes a spectroscope and a carriage moving unit. The spectroscope includes a wavelength-selective interference filter on which light from a measurement target is incident, and the carriage moving unit moves the spectroscope in an X direction with respect to the measurement target. If the measurement target is a color patch, the spectroscope performs spectrometry by changing a wavelength of light passing through the wavelength-selective interference filter in a first period during which the spectroscope is moved in the X direction, and passes light of an initial wavelength through the wavelength-selective interference filter at a start of measurement and at an end of measurement in the first period. A first output value that is a measured value from the spectrometry at the start of measurement is compared with a second output value that is a measured value from the spectrometry at the end of measurement.

An example system for inspecting a surface includes a laser, an optical system, a gated camera, and a control system. The laser is configured to emit pulses of light, with respective wavelengths of the pulses of light varying over time. The optical system includes at least one optical element, and is configured to direct light emitted by the laser to points along a scan line one point at a time. The gated camera is configured to record a fluorescent response of the surface from light having each wavelength of a plurality of wavelengths at each point along the scan line. The control system is configured to control the gated camera such that an aperture of the gated camera is open during fluorescence of the surface but closed during exposure of the surface to light emitted by the laser.

A flow cell device of the present invention comprises a flow path part in which a flow medium flows, and a flow cell part in which a flow path is formed.

A fluid medium monitoring apparatus of the present invention comprises: a light source unit for irradiating light; a first collimator unit for collimating light irradiated from the light source unit; a flow cell unit in which a fluid medium flows and light is allowed to absorb the wavelength of the fluid medium while proceeding along the moving direction of the fluid medium; and a light detection unit for detecting the wavelength of the light passing through the flow cell unit.