The invention provides a chirped laser dispersion spectrometer having two tunable lasers each with a bias current supply, a chirp signal source to provide a matching chirp pattern, a beam splitter to produce a single beam from the two first and second tunable lasers and active-phase locking means to render the two beams phase coherent and to produce a radio frequency carrier signal capable of programmable phase modulation by means of an optical beat signal. The invention also provides a method for generating at least two optical frequency signals for use in a frequency modulation spectroscopy (FMS) process for the detection and/or measurement of molecular species in a gas mixture and a method for generating at least two optical frequency signals for use in a chirped laser dispersion spectroscopy (CLaDS) process for the detection and/or measurement of molecular species in a gas mixture. The invention provides an efficient and cost-effective CLaDS system which maintains optical modulation whilst enabling greater change of the modulation frequency.

Provided are an apparatus and method for measuring quantum efficiency of a detector using a single pulse laser. Quantum efficiency of the measurement target detector may be measured from 420 nm to 1600 nm having uncertainty of 2% to 4% (K=2) by comparing the reference detector and the measurement target detector significantly different in sensitivity using a single laser pulse as a spectral light source. Also, it is possible to directly compare the two detectors with a significant difference in sensitivity through a very simple setup that causes a portion of a laser pulse output from a light source part to be absorbed by the reference detector and the laser pulse reflected from the reference detector to be irradiated to the measurement target detector.

Disclosed is a system and method for interrogating a photo-responsive material, such as for authentication purposes, utilizing a light source to illuminate a photo-responsive material, a detector to capture an emission from the photo-responsive material, and a processor to receive a response from the detector while the photo-responsive material is being illuminated after a maximum response has been received, then measuring a change in the received response.

A spectroscopic measurement apparatus includes a pulsed laser light source that emits pulsed laser light, a beam splitter that splits the pulsed laser light into pump light and probe light, a delay circuit that changes a delay time of the pump light with respect to the probe light, a chopper that intensity-modulates the pump light, a wavelength converter that wavelength-converts the probe light into vacuum ultraviolet light, an optical system that guides the pump light and the wavelength-converted probe light to a sample, and a detector that detects the probe light reflected by the sample.

Disclosed herein are a method for diagnosing a disease of a body tissue by using LIBS (Laser-Induced Breakdown Spectroscopy) comprising: preparing a laser device including: a laser projection module, outputting the laser to a suspicious region of the body tissue, a light receiving module, receiving a plurality of light, a spectrum measurement module, and a guide unit; and projecting the laser to generate plasma by inducing tissue ablation in the suspicious region; wherein the laser projected to the suspicious region has a target area, and wherein the target area has smaller size than the suspicious region such that the target area is located inside the suspicious region.

A spectroscopic laser sensor based on hybrid III-V/IV system-on-a-chip technology. The laser sensor is configured to either (i) be used with a fiber-optic probe connected to an intravenous/intra-arterial optical catheter for direct invasive blood analyte concentration level measurement or (ii) be used to measure blood analyte concentration level non-invasively through an optical interface attached, e.g., to the skin or fingernail bed of a human. The sensor includes a III-V gain-chip, e.g., an AlGaInAsSb/GaSb based gain-chip and a photonic integrated circuit, with laser wavelength filtering, laser wavelength tuning, laser wavelength monitoring, laser signal monitoring and signal output sections realized on a chip by combining IV-based semiconductor substrates and flip-chip AlGaInAsSb/GaSb based photodetectors and embedded electronics for signal processing. Embodiments of the invention may be applied for real-time monitoring of critical blood analyte concentration levels such as lactates, urea, glucose, ammonia, albumin, etc.

Disclosed is an optically pumped vertical cavity laser structure operating in the mid-infrared region, which has demonstrated room-temperature continuous wave operation. This structure uses a periodic gain active region with type I quantum wells comprised of InGaAsSb, and barrier/cladding regions which provide strong hole confinement and substantial pump absorption. A preferred embodiment includes at least one wafer bonded GaAs-based mirror. Several preferred embodiments also include means for wavelength tuning of mid-IR VCLs as disclosed, including a MEMS-tuning element. This document also includes systems for optical spectroscopy using the VCL as disclosed, including systems for detection concentrations of industrial and environmentally important gases.

Pulsed hyperspectral, fluorescence, and laser mapping imaging in a light deficient environment is disclosed. A system includes an emitter for emitting pulses of electromagnetic radiation and an image sensor comprising a pixel array for sensing reflected electromagnetic radiation. The system includes a controller configured to synchronize timing of the emitter and the image sensor. The system is such that at least a portion of the pulses of electromagnetic radiation emitted by the emitter comprises one or more of a hyperspectral emission, a fluorescence emission, or a laser mapping pattern.

An ultrahigh-resolution mid-infrared (MIR) dual-comb spectroscopy (DCS) measurement device includes a pump unit, a microring resonator (MRR) unit, a modulation unit, a splitting unit, a testing unit, a signal detection unit, a power balance unit, a reference detection unit and a spectral analysis unit. The measurement method includes: adjusting the laser emitted by the pump unit to the MRR unit; adjusting the modulation unit and performing dual-frequency modulation; generating two sets of MIR optical frequency combs (OFCs) with different repetition rates and splitting the MIR OFCs into the test light and the reference light; performing photoelectric conversion on the test light and injecting the test light to the spectral analysis unit; performing photoelectric conversion on the reference light and injecting the reference light to the spectral analysis unit; and performing Fourier transformation and data processing on test results to obtain absorption spectrum of the to-be-tested sample.

A dual-comb spectrometer 5 with two lasers 10, 12 serving as a local oscillator and an interrogator. The lasers output light beams with respective frequency combs C1, C2 of defined free spectral range, FSR. A detector 30 can detect heterodyne mixing of the combined beams to detect an RF frequency comb C3. Respective control signals are supplied to the lasers which have functional forms configured to cause the frequencies of the lasers' frequency combs C1, C2 to tune over a defined fraction of their FSR. This enables a reduction of the effective spectral sampling period by a factor equal to the ratio of the FSR to the spectral resolution of the spectrometer, which will typically be several orders of magnitude, so that the spectral sampling period can be reduced from the GHz to the MHz range, which in turn enables a gapless spectrum to be obtained in a short time.