A wafer includes a substrate layer, a first mirror layer having a plurality of two-dimensionally arranged first mirror portions, and a second mirror layer having a plurality of two-dimensionally arranged second mirror portions. In the wafer, a gap is formed between the first mirror portion and the second mirror portion so as to form a plurality of Fabry-Perot interference filter portions. A wafer inspection method according to an embodiment includes a step of performing faulty/non-faulty determination of each of the plurality of Fabry-Perot interference filter portions, and a step of applying ink to at least part of a portion overlapping the gap when viewed in a facing direction on the second mirror layer of the Fabry-Perot interference filter portion determined as faulty.

A hyperspectral imager (HSI) includes a first thin film filter, the first thin film filter including a first quarter wave mirror, a second quarter wave mirror, and a low-refractive-index wedge between the first quarter wave mirror and the second quarter wave mirror. The low-refractive-index wedge has a height dimension such that a distance between the first quarter wave mirror and the second quarter wave mirror increases linearly along a length of the low-refractive-index wedge.

A system and method for automated lens adjustment for hyperspectral imaging is described. The system includes an image sensor and an electrically-controllable element arranged to set a spectral band for image capture by (i) selectively providing light for a selected spectral band or (ii) selectively filtering light to a selected spectral band. The system includes a tunable lens that is adjustable to change a focal length of the lens; and one or more data storage devices storing data that indicates different focus adjustment parameters corresponding to different spectral bands. The system includes a control system configured to perform operations including: selecting a spectral band; controlling the electrically-controllable element to set the spectral band for image capture; retrieving the focus adjustment parameter that corresponds to the spectral band; adjusting the lens based on the retrieved focus adjustment parameter; and capturing an image of the subject while the lens remains adjusted.

A hyperspectral camera based on a continuously variable film filter and a coating method thereof can solve interference between partial bands of the hyperspectral camera based on the continuously variable film filter. The hyperspectral camera includes: a camera body and a detector chip, wherein a continuously variable film is coated on the detector chip; a semi-transmission half-cut filter is provided in front of the continuously variable film, and a distance between the semi-transmission half-cut filter and the continuously variable film is 0 mm. According to the present invention, the semi-transparent half-cut filter and the detector chip are integrated without any gap therebetween. As a result, optical interference caused by incident light sequentially passing through the semi-transparent half-cut filter and the detector chip is greatly reduced, which can reduce distortion of spectral signals, and finally satisfy wide-band application requirements which can be truly realized based on such technology.

A sensor system comprises a plurality of sets optical sensors arranged on an integrated circuit, the plurality of sets optical sensors having a respective top surface. The sensor system further comprising an interface between the plurality of optical sensors and a processing device configured to transmit information there between and an array of optical filters having a respective bottom surface and a respective top surface, where the bottom surface of the optical filter array is located proximal to the top surface of the plurality of sets optical sensors and each optical filter of the optical filter array is configured to pass a target wavelength range of light to a set of optical sensors. The processor is configured to receive an output from each optical sensor in a set of optical sensors and determine a corrected filter response for the set of optical sensors using crosstalk from light transmitted through optical filters adjacent to the set of optical sensors.

Embodiments of the systems can be configured to receive electromagnetic emissions of a substrate (e.g., a build material of a part being made via additive manufacturing) by a detector (e.g., a multi-spectral sensor) and generate a ratio of the electromagnetic emissions to perform spectral analysis with a reduced dependence on location and orientation of a surface of the substrate relative to the multi-spectral sensor. The additive manufacturing process can involve use of a laser to generate a laser beam for fusion of the build material into the part. The system can be configured to set the multi-spectral sensor off-axis with respect to the laser (e.g., an optical path of the multi-spectral sensor is at an angle that is different than the angle of incidence of the laser beam). This can allow the multi-spectral sensor to collect spectral data simultaneously as the laser is used to build the part.

An optical device including slots and an apparatus employing the optical device are provided. An optical unit device for selectively transmitting electromagnetic waves of a wavelength range, includes a material layer including slots. A gap between the slots has a distance such that the optical unit device has a Q-factor of about 5 or more.

An apparatus for detecting an ultraviolet blocking material includes a light receiver configured to acquire detection light from a target object; a spectrum signal generator configured to generate spectrum signals based on the detection light; and a processor configured to: select a reference wavelength from a range from about 290 nm to about 400 nm, and detect an ultraviolet blocking material based on a first spectrum signal of a first wavelength less than the reference wavelength and a second spectrum signal of a second wavelength greater than the reference wavelength, the first spectrum signal and the second spectrum signal being generated by the spectrum signal generator.

Pulsed fluorescence imaging in a light deficient environment is disclosed. A system includes an emitter for emitting pulses of electromagnetic radiation and an image sensor comprising a pixel array for sensing reflected electromagnetic radiation. The system includes a controller configured to synchronize timing of the emitter and the image sensor. The system is such that at least a portion of the pulses of electromagnetic radiation emitted by the emitter comprises electromagnetic radiation having a wavelength from about 795 nm to about 815 nm.

An imaging system uses a dynamically varying coded mask, such as a spatial light modulator (SLM), to time-encode multiple degrees of freedom of a light field in parallel and a detector and processor to decode the encoded information. The encoded information may be decoded at the pixel level (e.g., with independently modulated counters in each pixel), on a read-out integrated circuit coupled to the detector, or on a circuit external to the detector. For example, the SLM, detector, and processor may create modulation sequences representing a system of linear equations where the variables represent a degree of freedom of the light field that is being sensed. If the number of equations and variables form a fully determined or overdetermined system of linear equations, the system of linear equations' solution can be determined through a matrix inverse. Otherwise, a solution can be determined with compressed sensing reconstruction techniques with the constraint that the signal is sparse in the frequency domain.