Methods for wavelength determination of widely tunable lasers and systems thereof may be implemented with solid-state laser based photonic systems based on photonic integrated circuit technology as well as discrete table top systems such as widely-tunable external cavity lasers and systems. The methods allow integrated wavelength control enabling immediate system wavelength calibration without the need for external wavelength monitoring instruments. Wavelength determination is achieved using a monolithic solid-state based optical cavity with a well-defined transmission or reflection function acting as a wavelength etalon. The solid-state etalon may be used with a wavelength shift tracking component, e.g., a non-balanced interferometer, to calibrate the entire laser emission tuning curve within one wavelength sweep. The method is particularly useful for integrated photonic systems based on Vernier-filter mechanism where the starting wavelength is not known a-priori, or for compact widely tunable external cavity lasers eliminating the need for calibration of wavelength via external instruments.

The present invention relates to the design, construction, and operation for a diode-turret. Exemplary embodiments comprise several tens of laser diodes to function as a multiple-line radiation source. The invention further describes the construction for a socket-turret; this socket-turret will flexibly fit any numbers (limited only by the number of sockets available) of laser diodes. The invention further describes two radiation coupling-optics for the output from the turret of laser-diodes, one with an integrating sphere and another with a collimating scope. One operation method allows its user to set for any number of diode, functioning one diode at a time, sequentially, hopping from one diode to another, as a single-line radiation source for the spectrometry. Another operation method permits its user to set a group with any number of diodes, functioning several diodes simultaneously at a time, as a multiple-line radiation source for spectrometry.

A sensing system includes laser diodes with Bragg reflectors generating light having an initial light intensity and one or more near-infrared optical wavelengths. The laser diodes are modulated with a pulsed output with 0.5 to 2 nanosecond pulse duration. A beam splitter receives light from the laser diodes, splits the light into a received sample arm light directed to an object and a received reference arm light. A detection system includes a second lens and spectral filters in front of a photodiode array. The photodiode array is coupled to CMOS transistors and receives at least a portion of the received reference arm light and generates a reference detector signal. The detection system is synchronized with the laser diodes. A time-of-flight measurement is based on a comparison of the sample detector signal and the reference detector signal and measures a temporal distribution of photons in the received reflected sample arm light.

The present invention provides systems and methods for measuring the isotope ratios of one or more trace gases based on optical absorption spectroscopy methods. The system includes an optical cavity containing a gas. The system also includes a laser optically coupled with the optical cavity, and a detector system for measuring absorption of laser light by the gas in the cavity.

The present invention provides a system for measuring concentrations of trace gases in gas mixtures using an absorption spectroscopy method. The system comprising: a resonant optical cavity containing a gas mixture, a continuous-wave external cavity laser, a detector system for measuring an absorption of laser light by the gas in the resonant optical cavity, wherein the ratio of the round-trip length of the external cavity laser to the round-trip length of the resonant optical cavity or its inverse value is between N0.2 and N+0.2, where N is a positive integer number.

An optical particle sensor apparatus is equipped with a housing (MD) having an optical exit region (OF); an optical emitter device (LD) in the housing that is set up to emit an optical measurement beam (OB) for capturing particles; a focusing lens device (LE) in the housing for directing the optical measurement beam through the optical exit region to outside the housing in a focus region (FA), within which particle capturing is performable; an optical detector device (DD) arranged in the housing and set up to capture the measurement beam (OB) scattered by particles (P) and to output information produced using an algorithm relating to the presence of the particles; and a controllable adaptation device (C, E), which is set up to adapt at least one optical property of the lens device and/or of the optical emitter device and/or of the optical detector device based on an input signal (ES; ES) that provides information relating to a presence and to optical properties of an external optical window (EF) arranged between the optical exit region and the focus region, to capture a particle beyond the external optical window.

A fluid analyzer includes an optical source and detector defining a beam path of an optical beam, and a fluid flow cell on the beam path defining an interrogation region in a fluid channel in which the optical beam interacts with fluids. One or more flow-control devices conduct a particle in a fluid through the fluid channel. A motion system moves the interrogation region relative to the fluid channel in response to a motion signal, and a controller (1) generates the motion signal having a time-varying characteristic, (2) samples an output signal from the optical detector at respective intervals of the motion signal during which the interrogation region contains and does not contain the particle, and (3) determines from output signal samples a measurement value indicative of an optically measured characteristic of the particle.

A photo-thermal speckle spectroscopy device having an infrared laser, a visible laser, a foam, and a camera. The infrared and visible lasers are focused on the foam, which causes the visible laser to scatter. A camera records the speckle pattern, which shifts when the IR laser is turned on. The related method of photo-thermal speckle spectroscopy is also disclosed.

A spectrometry device includes a controller that: causes first irradiated light and second irradiated light to be irradiated from a first light emitter and a second light emitter at mutually different timings; stores information relating to a first light reception signal and information relating to a second light reception signal in a storage at mutually different timings, in synchronization with irradiation timings of the first irradiation light and the second irradiation light; acquires information relating to a first optical spectrum based on the information relating to the first light reception signal stored in the storage during a first time period; and acquires information relating to a second optical spectrum based on the information relating to the second reception signal stored in the storage during a second time period.

Systems and method are disclosed for measuring an analyte (e.g., glucose) in a fluid (e.g., blood) using a tunable source. The system can draw blood from a patient and deliver the blood to a sample cell. Some or a particular component of the fluid (e.g., plasma) may be positioned at a sample portion of the sample cell for measurement. The sample cell can include a cuvette with two window pieces defining a gap for fluid analysis. Wider gaps can facilitate measurement of larger biological fluid components, and laser optical sources can provide sufficient power to traverse larger gaps. Tunable sources can provide for measurement of a wider variety of components. Aspects of the system can be adjusted to accommodate measurement of multiple analytes with multiple wavelengths.