A method of identifying substances, such as atmospheric and greenhouse gases, comprises emitting modulated radiation of different wavelengths towards a target area, wherein the radiation is modulated using respective modulation codes for a predetermined number n of wavelength bands that correspond to a range across an absorption spectrum for the substance, and analyzing the spectrum of radiation from the target area to identify the gas in the target area. The spectrum is analyzed using a time correlation of the emitted modulated radiation and the detected radiation. The radiation is modulated using respective modulation codes for the different wavelengths, and the modulation codes may be modified by insertion of a gap between each bit of the modulation code, the gap having a duration of at least n-1 bits.

A device for real-time analysis of airborne chemical, biological and explosive substances has at least a gas analysis sensor, a fluorescence/luminescence sensor and a sensor for determining the particle size and number of particles. Each of the sensors is connected to a multireflection cell (multipass laser cell) as an open measurement path. In addition, the device also includes an evaluation unit for the real-time analysis of chemical, biological and explosive substances.

A system for measuring a target gas via laser absorption spectroscopy in an open-air configuration, comprising a mid-infrared distributed feedback interband cascade laser (mid-IR DFB-ICL) having a wavelength selected to correspond with a spectral absorption line of the target gas and first electronic circuitry to control the laser temperature, current and modulation frequency. The mid-IR DFB-ICL is mounted to a heat sink. The system includes an optical component that projects a beam of the mid-IR DFB-ICL onto a distal backscattering directionally-reflective target and an optical receiver assembly that receives a fraction of the laser light that is backscattered from the directionally-reflective target and focuses the collected light onto an uncooled photodetector having a spectral bandwidth and optical configuration selected to optimize signal-to-noise response to received laser light. The optical receiver assembly comprises a primary mirror for receiving laser light backscattered from the directionally-reflective target and focusing the collected light onto the uncooled photodetector.

Apparatus and associated methods relate to mode matching a plurality of optical beams to a corresponding plurality of optical power amplifiers. The mode-matched plurality of beams is generated by mode matching a single laser beam and then splitting the mode-matched beam into the plurality of beam-split portions. Each of the plurality of beam-split portions is then guided to a corresponding one of a plurality of optical power amplifiers that amplifies the beam-split portion guided thereto. Optical path lengths between the mode-matching optics and the plurality of optical power amplifiers are created to be substantially equal to one another thereby enabling optical mode matching of the mode-matched optical beam to each of the plurality of optical power amplifiers.

A floodwater risk assessment system for a vehicle includes one or more cameras oriented to collect image data of floodwater located along a roadway the vehicle is traveling along, a time-of-flight sensor system that directs a laser beam towards a plurality of target points disposed along the floodwater one or more controllers in electronic communication with the one or more cameras and the time-of-flight sensor system. The one or more controllers execute instructions to determine a risk associated with crossing the floodwater at each of the plurality of target points located along the floodwater based on a flow speed of the floodwater and a floodwater depth. The one or more controllers generate a notification indicating the risk associated with crossing the floodwater at the plurality of target points located along the floodwater.

According to a method for cavity enhanced microscopy, a sample is arranged on a sample carrier of an optical cavity, which is formed by a pair of opposing mirrors. A description defining a lateral motion of the sample during a predefined time interval and a variation of the cavity length during the time interval in a temporally synchronized manner is stored and an actuator system is triggered to move the sample carrier and/or at least one mirror of the pair of mirrors to effect the lateral motion of the sample with respect to the cavity and the variation of the cavity length according to the description. Light is introduced into the cavity and transmitted portions and/or reflected portions and/or scattered portions and/or emitted portions are detected to generate a sensor dataset.

The application relates to a method for determining at least one speed component of a fluid stream, in particular for laser Doppler anemometry, the method having at least the steps of: providing at least a first part-beam and a second part-beam; directing the first part-beam along a first optical path and directing the second part-beam along a second optical path onto a superimposition region within the fluid stream so that the first optical path and the second optical path intersect in the superimposition region; detecting a Doppler-shifted first part-beam scattered light signal, which was back-scattered by tracer particles in the fluid stream in the superimposition region, at least partially following the first optical path; detecting a Doppler-shifted solid angle scattered light signal, which was scattered by the tracer particles in the superimposition region into a path different at least from the first optical path and from the second optical path. The application also relates to a corresponding device.