An active remote sensing system is provided with an array of laser diodes that generate light directed to an object having one or more optical wavelengths that include at least one near-infrared wavelength between 700 nanometers and 2500 nanometers. One of the laser diodes pulses with pulse duration of approximately 0.5 to 2 nanoseconds at repetition rate between one kilohertz and about 100 megahertz. A beam splitter receives the laser light, separates the light into a plurality of spatially separated lights and directs the lights to the object. A detection system includes a photodiode array synchronized to the array of laser diodes and performs a time-of-flight measurement by measuring a temporal distribution of photons received from the object. The time-of-flight measurement is combined with images from a camera system, and the remote sensing system is configured to be coupled to a wearable device, a smart phone or a tablet.

The present disclosure provides a Scheimpflug LIDAR apparatus for detecting a property of a gas comprising: a light source configured to emit a light along at least a first axis, a light detection arrangement, and an optical configuration fulfilling the Scheimpflug condition and Hinge rule. The light source comprises an expander aperture, and wherein the expander aperture and light detection arrangement are configured such that: a spot size of the emitted light along the first axis is matched to a pixel footprint of pixels configured to receive light from corresponding distances along the first axis, and an effective range resolution of at least one column of pixels or probe volume deteriorates linearly with respect to the range.

An optical system measures one or more physiological parameters with a wearable device that includes a light emitting diode (LED) source including a driver and a plurality of semiconductor sources that generate an output optical light. One or more lenses deliver a lens output light to tissue of a user. A detection system receives at least a portion of the lens output light reflected from the tissue and generates an output signal having a signal-to-noise ratio. The detection system comprises a plurality of spatially separated detectors and an analog to digital converter. The detection system increases the signal-to-noised ratio by comparing a first signal with the LEDs off to a second signal with the LEDs on. An imaging system including a Bragg reflector is pulsed and has a near infrared wavelength. A beam splitter splits the light into a sample arm and a reference arm to measure time-of-flight.

Devices, systems, and methods for determining gas characteristics to monitor transformer operation include extracting gas from transformer fluid for analysis.

A photonic millimeter-wave oscillator is based on a heterodyne beatnote of two continuous wave lasers and is configured to provide a narrow linewidth output when the frequency difference is disciplined with rotational spectroscopy of molecules using frequency modulation spectroscopy.

A method of measuring the concentration of a gas in a target environment using a laser lidar system, comprises directing a laser beam towards an environment containing the gas, tuning the laser wavelength over a wavelength range including the absorption line of the gas, and measuring intensity of laser light returned from the environment containing the gas, as a result of scattering as a function of time. The intensity vs time is then converted into gas absorption vs wavelength, and the gas absorption vs wavelength is used to determine the concentration of the gas in the target environment.

Sensor and method for detecting road conditions while a vehicle is moving, the sensor comprising a dual optical frequency comb, optical means for directing the output beam of the comb towards a verification site of the road, a photodetector and receiving optics for directing the back reflected light towards the photodetector, the photodetector being provided with electronics for obtaining the RF spectrum of the detected signal and resolving the optical spectrum of the verification region from the RF spectrum.

A method of operating an optical device, the method comprising tuning a first emission wavelength of a first output radiation of a laser device continuously within a first wavelength spectrum by modulating a drive current thereof with a first drive current modulation having a frequency of at least 100 kHz. The first wavelength spectrum comprises a first spectral feature associated with at least part of a gas absorption spectrum of at least one gas. The method comprises the steps of modulating the first output radiation of the laser device with a first output modulation, the first output modulation comprising a first plurality of binary pulses, scanning the first wavelength spectrum at a rate of at least 1 μm per second, projecting the first output radiation towards a first target area, receiving scattered radiation from the first target area, and processing the scattered radiation.

The invention relates to a method for controlling a semiconductor-laser-diode-based SS-interferometer system (SS=swept source), which allows for a wide range of application and is suitable for use in ophthalmology, in particular for imaging and for determining biometric measurement values of the eye. In the method according to the invention, by means of periodic current modulation, the operation of single semiconductor laser diodes is designed such that a highly coherent spectral laser line can be adjusted with a highest possible repetition rate and over a wide wavelength range. In addition, the following parameters: centre wavelength, sweep rate, sweep range, optical power in the eye and coherence length are adjusted such that the method is suitable for imaging and biometric applications via whole-eye scans. The proposed semiconductor-laser-diode-based SS-interferometer system is provided, in particular, for biometric measuring of the eye. Given that the embodiments are based preferably on optical, coherence tomographic scan images, the main application lies in opthalmological diagnostics, treatment and the preparation of surgical procedures and follow-up thereof.

A method or system of determining integrity of a closed container comprising at least one gas. The determination is based on applying a mechanical force to at least one side of the container and transmitting a light signal across at least a portion of an outside surface of at least one side of the container using an optical sensor. The optical sensor is sensitive to the at least one gas inside the container. Detecting a transmitted light signal and determining, based on the detected light signal, if the at least one gas inside the container has been detected outside of the container.