Colorado State University Research Foundation

National Technology & Engineering Solutions of Sandia, LLC

Azer P Yalin

Bryan Willson

Morgan Defoort

Sachin Joshi

Adam Reynolds

John Volckens

David Leith

Kimberly Anderson

Owen Johns

Mwangi T Ndonga

Charles E Rose

Christopher M Limbach

Sean Simpson

Ciprian Dumitrache

Systems and methods are disclosed to determine the concentration of a species within a sample. An example method may include collecting optical loss data over a range of frequencies from the sample using a spectroscopy system; placing the optical loss data into a plurality of bins, each bin having a defined frequency width; determining an average optical loss data value for the optical loss values within each bin that have an optical loss value less than a threshold value; removing the optical loss data within each bin having a value outside a tolerance range bounding the average optical loss data value for the respective bin; fitting a spectral curve to the remaining optical loss data; and determining the concentration of the species within the sample based on the spectral curve.

Laser sensor for trace gas detection

A photonic-crystal-fiber-delivered laser-triggered high-voltage gas switch can deliver a peak irradiance of greater than 5.1&#xd7;10W/cmto the AK gap for a laser having a wavelength of 1064 nm. The switch is capable of operating at pressures up to 2200 psi; voltages across the gap of greater than 200 kV; operation at less than 70% self-break voltage; shot-to-shot jitter of less than 3 ns; AK gap distances of 3 mm or smaller; and triggering via a fiber-delivered laser pulse energy of as low as 500 &#x3bc;J.

Photonic-crystal-fiber-delivered laser-triggered high-voltage gas switch

Methods and systems for characterizing particles in an aerosol are disclosed. A system includes a collection container that utilizes the principles of elutriation to collect particles of selected aerodynamic diameter ranges within a measurement region. A particle detector is used to detect and characterize particles that have settled into the measurement region.

Portable particle spectrometer

An apparatus and method for transmission of laser pulses with high output beam quality using large core step-index silica optical fibers having thick cladding, are described. The thick cladding suppresses diffusion of modal power to higher order modes at the core-cladding interface, thereby enabling higher beam quality, M, than are observed for large core, thin cladding optical fibers. For a given NA and core size, the thicker the cladding, the better the output beam quality. Mode coupling coefficients, D, has been found to scale approximately as the inverse square of the cladding dimension and the inverse square root of the wavelength. Output from a 2 m long silica optical fiber having a 100 &#x3bc;m core and a 660 &#x3bc;m cladding was found to be close to single mode, with an M=1.6. Another thick cladding fiber (400 &#x3bc;m core and 720 &#x3bc;m clad) was used to transmit 1064 nm pulses of nanosecond duration with high beam quality to form gas sparks at the focused output (focused intensity of &#x3e;100 GW/cm), wherein the energy in the core was &#x3c;6 mJ, and the duration of the laser pulses was about 6 ns. Extending the pulse duration provided the ability to increase the delivered pulse energy (&#x3e;20 mJ delivered for 50 ns pulses) without damaging the silica fiber.

Transmission of laser pulses with high output beam quality using step-index fibers having large cladding

A spark delivery system for generating a spark using a laser beam is provided, and includes a laser light source and a laser delivery assembly. The laser delivery assembly includes a hollow fiber and a launch assembly comprising launch focusing optics to input the laser beam in the hollow fiber. The laser delivery assembly further includes exit focusing optics that demagnify an exit beam of laser light from the hollow fiber, thereby increasing the intensity of the laser beam and creating a spark. Other embodiments use a fiber laser to generate a spark. Embodiments of the present invention may be used to create a spark in an engine. Yet other embodiments include collecting light from the spark or a flame resulting from the spark and conveying the light for diagnostics. Methods of using the spark delivery systems and diagnostic systems are provided.

Optical diagnostics integrated with laser spark delivery system

A spark delivery system for generating a spark using a laser beam is provided, the spark delivery system including a laser light source and a laser delivery assembly. The laser delivery assembly includes a hollow fiber and a launch assembly comprising launch focusing optics to input the laser beam in the hollow fiber. In addition, the laser delivery assembly includes exit focusing optics that demagnify an exit beam of laser light from the hollow fiber, thereby increasing the intensity of the laser beam and creating a spark. In accordance with embodiments of the present invention, the assembly may be used to create a spark in a combustion engine. In accordance with other embodiments of the present invention, a method of using the spark delivery system is provided. In addition, a method of choosing an appropriate fiber for creating a spark using a laser beam is also presented.

Growing community of inventors

Fort Collins, CO, United States of America

Azer P Yalin