A dual optical frequency comb light-emitting device includes a first optical-frequency-comb laser source that includes a first laser resonator having a first optical path length, a second optical-frequency-comb laser source that includes a second laser resonator having a second optical path length different from the first optical path length, and an optical coupler that causes a first portion of first optical-frequency-comb laser light emitted from the first laser resonator to enter the second laser resonator. The first optical-frequency-comb laser source outputs a second portion of the first optical-frequency-comb laser light to an outside. The second optical-frequency-comb laser source outputs second optical-frequency-comb laser light emitted from the second laser resonator to the outside.

Systems and method for analysing contaminants of a gas sample of natural gas are provided. An interrogation light beam propagates into a chamber of a multipass gas cell receiving the gas sample. The interrogation light beam has a wavelength controlled to alternately correspond to an absorption wavelength of H.sub.2S and an absorption wavelength of an additional gas contaminant. The additional gas contaminant may for example be CO.sub.2 or H.sub.2O. In some implementation, a single laser emitter may be used to generate the interrogation light beam at the H.sub.2S and CO.sub.2 wavelengths. In some implementations, two different laser emitters may be used to generate the interrogation light beam at the H.sub.2S and H.sub.2O wavelengths. A WMS detection scheme may be used.

Systems and method for analysing contaminants of a gas sample of natural gas are provided. An interrogation light beam propagates into a chamber of a multipass gas cell receiving the gas sample. The interrogation light beam has a wavelength controlled to alternately correspond to an absorption wavelength of H.sub.2S and an absorption wavelength of an additional gas contaminant. The additional gas contaminant may for example be CO.sub.2 or H.sub.2O. In some implementation, a single laser emitter may be used to generate the interrogation light beam at the H.sub.2S and CO.sub.2 wavelengths. In some implementations, two different laser emitters may be used to generate the interrogation light beam at the H.sub.2S and H.sub.2O wavelengths. A WMS detection scheme may be used.

Method and gas analyzer for measuring the concentration of a gas component in a measurement gas, a wavelength-tunable laser diode is actuated with a current, one part of the light generated by the laser diode is guided through the measurement gas to a measuring detector to generate a measuring signal, the other part of the light is guided to a monitor detector to generate a monitor signal, the current is varied in periodically consecutive scanning intervals to scan an absorption line of interest of the gas component as a function of the wavelength, the current is further modulated with a radio-frequency noise signal having a lower cut-off frequency selected as a function of the properties of the laser diode and high enough to ensure no wavelength modulation occurs and the measuring signal is correlated with the monitor signal and then evaluated to generate a measurement result.

In swept source Raman (SSR) spectroscopy, a swept laser beam illuminates a sample, which inelastically scatters some of the incident light. This inelastically scattered light is shifted in wavelength by an amount called the Raman shift. The Raman-shifted light can be measured with a fixed spectrally selective filter and a detector. The Raman spectrum can be obtained by sweeping the wavelength of the excitation source and, therefore, the Raman shift. The resolution of the Raman spectrum is determined by the filter bandwidth and the frequency resolution of the swept source. An SSR spectrometer can be smaller, more sensitive, and less expensive than a conventional Raman spectrometer because it uses a tunable laser and a fixed filter instead of free-space propagation for spectral separation. Its sensitivity depends on the size of the collection optics. And it can use a nonlinearly swept laser beam thanks to a wavemeter that measures the beam's absolute wavelength during Raman spectrum acquisition.

A spectroscopic apparatus includes a splitter that receives a first detected signal output from a sample to which an incident beam is irradiated, and outputs a reflected signal and a second detected signal by splitting the first detected signal, and a signal processor that receives the reflected signal and the second detected signal, and extracts a Raman signal from the second detected signal in response to the received reflected signal.

The present invention relates to an analysis apparatus adapted to analyze a measurement target component contained in a sample by irradiating a measurement cell into which the sample is introduced with pulse-oscillated light, whereby suppressing reduction in wavelength resolution without shortening the pulse width. The analysis apparatus includes multiple light sources adapted to produce pulse oscillations, a light detector adapted to detect light emitted from the light source and transmitted through the measurement cell, and a signal separation part adapted to separate, from a light intensity signal obtained by the light detector, signals corresponding to a part of pulses from the light sources.

The present disclosure provides a method and device for identifying a light source. The method includes as follows. M stripe sets in an image may be detected. A first energy spectrum data corresponding to each of M stripe sets may be obtained. A second energy spectrum data corresponding to each light source in a database may be obtained. The database may include K light sources, and the energy spectrum data corresponds to an identity of the light source. A correlation coefficient between the second energy spectrum data and the first energy spectrum data may be calculated to obtain M*K correlation coefficients. The identity of each stripe set corresponding to the light source in the database may be determined according to the M*K correlation coefficients. With this disclosure, the tracking of the light source emitted by a controller can be achieved.

In multicolor Coherent anti-Stokes Raman Scattering, a fingerprint region is a region densely filled with signals, and information about an intensity or spatial distribution of the signals is important for cell analysis. However, when laser power was increased due to the low signal intensity, there was a problem that cells were damaged. Thus, the present invention was configured such that the number of pulses of laser light emitted from a short pulse laser light source was changed by a pulse modulator. Accordingly, damage to the cells can be suppressed without significant reduction in signal intensity.

A spectroscopic analysis apparatus includes a laser light source that emits laser light, of which wavelength changes, toward a reflector inside a probe, the probe being configured to be disposed in a flow passage of a measurement target fluid, a light receiver that receives the laser light reflected by the reflector, and a controller that analyzes the measurement target fluid using a result of reception acquired by the light receiver and controlling the laser light source. The controller controls the laser light source to perform at least one scan of the laser light, the controller controlling the laser light source such that a scanning time of the laser light is equal to or shorter than a light-receivable time of the laser, the scanning time being a time to scan the laser light emitted from the laser light source in a certain wavelength range, the light-receivable time being a time in which the laser light reflected by the reflector can be received by the light receiver.