A low cost, low power, passive optical methane monitoring system for fixed-position installation at oil and gas production well pads and gathering centers is disclosed. The optical methane monitoring system disclosed can be a scannable field of view Near Infrared (NIR) filter photometer to detect and quantify methane concentration in a two dimensional or a three dimensional grid above and around a facility. A randomized fiber optic bundle is disclosed that can be used to direct the total optical power from a collection lens to two or more isolated optical channels. Band pass filters isolate a desired wavelength range for transmission measurements for the two or more channels. Also disclosed is an absorption algorithm which accounts for variable background spectral intensity as well as correcting for water vapor and overall scattering effects to measure methane concentration for a given field of view.

A reflectometry instrument includes a light source for emitting an illumination beam that illuminates the macula. A portion of the illumination beam is reflected from the macula and forms a detection beam. The detection beam is indicative of macular pigment in the macula. The instrument also includes a first mirror for reflecting the illumination beam toward the macula and for reflecting the detection beam from the macula. The instrument is configured so that the illumination beam and the detection beam remain separated between the macula and the first mirror.

Optical spectrometers may be used to determine the spectral components of electromagnetic waves. Spectrometers may be large, bulky devices and may require waves to enter at a nearly direct angle of incidence in order to record a measurement. What is disclosed is an ultra-compact spectrometer with nanophotonic components as light dispersion technology. Nanophotonic components may contain metasurfaces and Bragg filters. Each metasurface may contain light scattering nanostructures that may be randomized to create a large input angle, and the Bragg filter may result in the light dispersion independent of the input angle. The spectrometer may be capable of handling about 200 nm bandwidth. The ultra-compact spectrometer may be able to read image data in the visible (400-600 nm) and to read spectral data in the near-infrared (700-900 nm) wavelength range. The surface area of the spectrometer may be about 1 mm.sup.2, allowing it to fit on mobile devices.

A surgical visualization feedback system is disclosed. The surgical visualization feedback system comprises an emitter assembly configured to emit electromagnetic radiation toward an anatomical structure. The emitter assembly comprises a structured light emitter configured to emit a structured light pattern on a surface of the anatomical structure and a spectral light emitter configured to emit spectral light capable of penetrating the anatomical structure. The surgical visualization feedback system further comprises a waveform sensor assembly configured to detect reflected electromagnetic radiation corresponding to the emitted electromagnetic radiation and a control circuit in signal communication with the waveform sensor assembly. The control circuit is configured to receive an input corresponding to a selected surgical procedure, determine an identity of a targeted structure within the anatomical structure based on the selected surgical procedure and the reflected electromagnetic radiation, and confirm the determined identity of the targeted structure through a user input.

A method of operating a hyperspectral imaging device includes connecting electrodes on a liquid crystal variable retarder to a voltage source, rotating liquid crystal material in the liquid crystal variable retarder between a first orientation with a certain optical phase delay and a second orientation with a different optical phase delay, receiving a beam of light at an image sensor that has passed through the liquid crystal variable retarder, and producing an output signal from the image sensor.

A reflective spatial light modulator (SLM) made of an electro-optic material in a one-sided Fabry-Perot resonator can provide phase and/or amplitude modulation with fine spatial resolution at speeds over a Gigahertz. The light is confined laterally within the electro-optic material/resonator layer stack with microlenses, index perturbations, or by patterning the layer stack into a two-dimensional (2D) array of vertically oriented micropillars. Alternatively, a photonic crystal guided mode resonator can vertically and laterally confine the resonant mode. In phase-only modulation mode, each SLM pixel can produce a π phase shift under a bias voltage below 10 V, while maintaining nearly constant reflection amplitude. This high-speed SLM can be used in a wide range of new applications, from fully tunable metasurfaces to optical computing accelerators, high-speed interconnects, true 2D phased array beam steering, beam forming, or quantum computing with cold atom arrays.

Apparatuses and methods for microscopic analysis of a sample using spatial light manipulation to increase signal to noise ratio are described herein.

A spectrometry system for spectroscopically analyzing a sample is provided. The system includes an excitation source for interacting with the sample; a detector for detecting at least a portion of light absorbed or emitted by the sample, the excitation source and detector being optically coupled via an optical pathway; and an aperture positioned in the optical pathway for limiting transmission of light from the excitation source to the detector; wherein the aperture is configured to have a spatially varying distribution of one or more geometric features that provide regions of variable transmission around an edge of the aperture. Also provided is a mask for use with a spectrometry system, the mask configured to be positioned in an optical pathway between an excitation source and a detector, wherein the mask has a spatially varying distribution of one or more geometric features that provide regions of variable transmission around an edge of the aperture. A method for limiting light throughput from an excitation source to a detector via an aperture in a spectrometry system is also provided.

Apparatus and methods are presented for spectral domain optical imaging, in particular for single shot 3-D spectral domain imaging of the retina of the human eye. In certain embodiments one or more 3-D images across elongated areas of an object are acquired, with scanning perpendicular to the long axis of the elongated areas for imaging extended volumes of the object. In preferred embodiments the captured light is sampled in the Fourier plane, in a dimension substantially perpendicular to the long axis, with a cylindrical lenslet array, while in other embodiments the captured light is sampled in the image plane. Apparatus and methods are also presented for hyperspectral imaging of the retina, with the illuminating beams preferably angled to suppress interference from corneal reflections. Apparatus and methods are also presented for multi-wavelength wavefront sensing, with simultaneous capture of light in two or more paths with different delays.

Spectroferometers and methods of use are provided. The spectroferometers includes an enclosure, one or more interferometer beam-splitting elements, and one or more spectrometer beam-dispersing elements. The one or more interferometer beam-splitting elements and the one or more spectrometer beam-dispersing elements are housed in the enclosure, share one or more radiation sensitive elements, which are arranged to generate a signal in response to incident electromagnetic radiation, and each generate one or more optical outputs. The one or more optical outputs are arranged such that respective optical axes intersect substantially in a plane of the one or more radiation sensitive elements.