Hyperspectral imaging spectrometers have applications in environmental monitoring, biomedical imaging, surveillance, biological or chemical hazard detection, agriculture, and minerology. Nevertheless, their high cost and complexity has limited the number of fielded spaceborne hyperspectral imagers. To address these challenges, the wide field-of-view (FOV) hyperspectral imaging spectrometers disclosed here use computational imaging techniques to get high performance from smaller, noisier, and less-expensive components (e.g., uncooled microbolometers). They use platform motion and spectrally coded focal-plane masks to temporally modulate the optical spectrum, enabling simultaneous measurement of multiple spectral bins. Demodulation of this coded pattern returns an optical spectrum in each pixel. As a result, these computational reconfigurable imaging spectrometers are more suitable for small space and air platforms with strict size, weight, and power constraints, as well as applications where smaller or less expensive packaging is desired.

Hyperspectral imaging spectrometers have applications in environmental monitoring, biomedical imaging, surveillance, biological or chemical hazard detection, agriculture, and minerology. Nevertheless, their high cost and complexity has limited the number of fielded spaceborne hyperspectral imagers. To address these challenges, the wide field-of-view (FOV) hyperspectral imaging spectrometers disclosed here use computational imaging techniques to get high performance from smaller, noisier, and less-expensive components (e.g., uncooled microbolometers). They use platform motion and spectrally coded focal-plane masks to temporally modulate the optical spectrum, enabling simultaneous measurement of multiple spectral bins. Demodulation of this coded pattern returns an optical spectrum in each pixel. As a result, these computational reconfigurable imaging spectrometers are more suitable for small space and air platforms with strict size, weight, and power constraints, as well as applications where smaller or less expensive packaging is desired.

A spectroscope for measuring a spectrum of input light includes a fringe former that forms first fringes having a first pitch by splitting the input light, a diffraction grating that disperses each of the first fringes, a moire pattern former that forms a moire pattern by overlaying the first fringes that have been dispersed, on second fringes having a second pitch different from the first pitch, and an image pickup device that measures the spectrum of the input light by detecting the moire pattern. At least one of the fringe former and the moire pattern former includes a cylindrical lens array.

In a method for measuring radiation, the radiation is temporally and/or spatially separated by a modulator to direct at least N different combinations of radiation incident on each region into at least two and fewer than N distinct directions. The total intensity of radiation in each direction is measured with a detector for each modulator configuration and the detector outputs are analyzed statistically to obtain information relating to the spectral properties of the radiation. In this way substantially all of the energy received at the entrance aperture of a measurement device is encoded into multiple outputs and the multiplexed output is received by a small number of detectors.

Embodiments are directed to an optical spectrometry method, comprising: generating a sequence of 2D Hadamard masks along the time dimension, wherein each 2D Hadamard mask is arranged with a wavelength dimension and a coefficient dimension; detecting an optical signal from light transmitted through the sequence of 2D Hadamard masks; and reconstructing a spectrum to be detected by analyzing the optical signal, wherein each 2D Hadamard mask in the sequence of 2D Hadamard masks comprises a plurality of columns along the wavelength dimension, each column corresponding to a different Hadamard coefficient, and having different respective sequency values along the time dimension.

An optical filter including filter regions arrayed two-dimensionally, in which the filter regions include a first region and a second region; a wavelength distribution of an optical transmittance of the first region has a first local maximum in a first wavelength band and a second local maximum in a second wavelength band that differs from the first wavelength band, and a wavelength distribution of an optical transmittance of the second region has a third local maximum in a third wavelength band that differs from each of the first wavelength band and the second wavelength band and a fourth local maximum in a fourth wavelength band that differs from the third wavelength band.

A spectroscope for measuring a spectrum of input light includes a fringe former that forms first fringes having a first pitch by splitting the input light, a diffraction grating that disperses each of the first fringes, a moire pattern former that forms a moire pattern by overlaying the first fringes that have been dispersed, on second fringes having a second pitch different from the first pitch, and an image pickup device that measures the spectrum of the input light by detecting the moire pattern. At least one of the fringe former and the moire pattern former includes a cylindrical lens array.

Infrared (IR) vibrational scattering scanning near-field optical microscopy (s-SNOM) has advanced to become a powerful nanoimaging and spectroscopy technique with applications ranging from biological to quantum materials. However, full spatiospectral s-SNOM continues to be challenged by long measurement times and drift during the acquisition of large associated datasets. Various embodiments provide for a novel approach of computational spatiospectral s-SNOM by transforming the basis from the stationary frame into the rotating frame of the IR carrier frequency. Some embodiments see acceleration of IR s-SNOM data collection by a factor of 10 or more in combination with prior knowledge of the electronic or vibrational resonances to be probed, the IR source excitation spectrum, and other general sample characteristics.

An optical filter including filter regions arrayed two-dimensionally, in which the filter regions include a first region and a second region; a wavelength distribution of an optical transmittance of the first region has a first local maximum in a first wavelength band and a second local maximum in a second wavelength band that differs from the first wavelength band, and a wavelength distribution of an optical transmittance of the second region has a third local maximum in a third wavelength band that differs from each of the first wavelength band and the second wavelength band and a fourth local maximum in a fourth wavelength band that differs from the third wavelength band.

Methods and systems for measuring one or more properties of a sample are disclosed. The methods and systems can include multiplexing measurements of signals associated with a plurality of wavelengths without adding any signal independent noise and without increasing the total measurement time. One or more levels of encoding, where, in some examples, a level of encoding can be nested within one or more other levels of encoding. Multiplexing can include wavelength, position, and detector state multiplexing. In some examples, SNR can be enhanced by grouping together one or more signals based on one or more properties including, but not limited to, signal intensity, drift properties, optical power detected, wavelength, location within one or more components, material properties of the light sources, and electrical power. In some examples, the system can be configured for optimizing the conditions of each group individually based on the properties of a given group.