A method includes directing a first plurality of probe laser pulses through a sample, dividing each of the first plurality of probe laser pulses to generate a first interferogram, and generating first image data reproducible as a first phase image of the sample. A plurality of pump laser bursts are directed onto the sample to heat the sample. A second plurality of probe laser pulses are directed through the sample at a predetermined time delay. Each of the second plurality of probe laser pulses are divided to generate a second interferogram. Second image data is generated that is reproducible as a second phase image of the sample. A transient phase shift is determined in the second phase image relative to the first phase image. A vibrational spectroscopy property is determined of the sample based on the transient phase shift, thereby allowing an identification of chemical bond information of within the sample.

Improved cavity enhanced absorption spectroscopy is provided using a piecewise tunable laser by using a lookup table for laser tuning that is configured specifically for this application. In preferred embodiments this is done in combination with a laser control strategy that provides precise wavelength determination using cavity modes of the instrument as a reference.

The present invention relates to the design, construction, and operation of a laser air-sampling multi-spectrometer; its operation with variable laser energy to simultaneously and/or sequentially perform spectrometric techniques of LAS, LEFS, RSS, and LIBS. The combined spectrometric operation will detect gas and particulate chemicals directly in a flowing stream of air sample and/or particulate chemicals on filter collected from the flowing stream of air sample.

Methods and apparatus are disclosed for detecting one or more species in a sample, wherein laser probe light is frequency swept across at least one infra red absorption spectrum feature of each of the species. A path from the probe light source to a single detector element may be switched between at least one sample absorption cell or volume and one or more reference cells or volumes.

A standard reference material interface for a Raman probe includes a locator including a housing having a first end and a second end, the first end including an attachment portion configured to mate with an attachment portion of the Raman probe. The locator defines a central axis that intersects the first end and the second end. The standard reference material interface also includes a hermetically sealed standard reference material enclosure positioned at the second end of the housing and enclosing a standard reference material. An optical port is positioned within the housing between the Raman probe and the standard reference material relative to the central axis. The optical port includes a window.

A method of quantifying at least one property of interest of an oil sands ore sample is provided using a laser-induced breakdown spectroscopy (LIBS) method. The property of interest may include bitumen content, water content, particle size information, cation exchange capacity, methylene blue index, mineralogical content (e.g., quartz, total clay, and clay components), amorphous material content, total ash content, and connate water parameter (e.g., conductivity, chloride content, or alkalinity).

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 comprising two lasers outputting respective frequency combs having a frequency offset between their intermode beat frequencies. One laser acts as a master and the other as a follower. Although the master laser is driven nominally with a DC drive signal, the current on its drive input line nevertheless oscillates with an AC component that follows the beating of the intermode comb lines lasing in the driven master laser. This effect is exploited by tapping off this AC component and mixing it with a reference frequency to provide the required frequency offset, the mixed signal then being supplied to the follower laser as the AC component of its drive signal. The respective frequency combs in the optical domain are thus phase-locked relative to each other in one degree of freedom, so that the electrical signals obtained by multi-heterodyning the two optical signals are frequency stabilized.

A gas measurement system as disclosed can include a coherent light source, which emits a light beam; a detector; a beam path formed between the light source) and the detector; and a gas cell arranged in the beam path such that the detector receives light transmitted through the gas cell. The gas cell can include a porous ceramic and have an optical path length which is a multiple of the actual layer thickness of the gas cell. A optical element can be arranged in the beam path between the light source and the gas cell with the light beam emitted by the light being widened and unfocussed as the light beam enters the gas cell.

Disclosed herein are a diagnostic method using laser induced breakdown spectrum analysis and a diagnostic device for performing the same. The diagnostic device may include a laser projection module projecting a pulsed laser to a specimen, a light receiving module receiving a light generated by a plasma ablation induced at the specimen by the pulsed laser, a spectral member receiving and dividing the light generated by the plasma ablation; a sensor array including a plurality of sensors arranged to receive the divided light for each wavelength, and a controller obtaining spectrum data of the light generated by the plasma ablation from a specific exposure period, and determining whether or not the specimen is diseased based on the spectrum data of the light generated by the plasma ablation.