Stephen Richard Friberg, Age 74129 Concord Cir, Mountain View, CA 94040

6775001, Aug 10, 2004

Feb 28, 2003

10/377976

Stephen R. Friberg - Mountain View CA
Charles C. Harb - Pasadena CA

Lambda Control, Inc. - Mountain View CA

G01N 2100

356437, 356432, 356433, 356435

A laser absorption spectrometer for making measurements of absorption spectra which includes a wavelength sensor that can measure the average wavelength of pulses from a laser on a pulse-by-pulse basis and that can measure the internal wavelength variation of laser pulses. The laser absorption spectrometer can be used with pulsed lasers like the quantum cascade laser to perform sensitive measurements of the absorption spectra even when there is pulse-to-pulse variation of average wavelength and when there are internal changes in the wavelength of the pulses.

6836330, Dec 28, 2004

Mar 28, 2002

10/112985

Stephen R. Friberg - Mountain View CA
Charles C. Harb - Sunnyvale CA

Lambda Control, Inc. - Sunnyvale CA

G01N 2125

356419, 356416, 250225, 250226

A wavelength detector is described. The wavelength detector includes a beamsplitter having a wedged back surface with respect to the front surface to reflect the incoming optical signal into two paths. Filters, at least one of which varies with wavelength of the optical signal are in each of the said paths. The filtered light in the two paths is detected by a photodetector and the output electrical signals are log amplified. The log amplified signals are applied to a difference amplifier whose output is indicative of the wavelength or polarization of the incident optical signal.

2002009, Jul 18, 2002

Sep 17, 2001

09/954086

Stephen Friberg - Mountain View CA, US
Charles Harb - Sunnyvale CA, US

G01J003/52

356/419000

A wavelength detector is described. The wavelength detector directs an incoming optical signal into two paths, at least one of which varies with wavelength of the optical signal. The light in the two paths is detected by a photodetector and the output electrical signals are log amplified. The log amplified signals are applied to a difference amplifier whose output is indicative of the wavelength of the incident optical signal.

2014014, May 29, 2014

Mar 15, 2013

13/835403

- Milpitas CA, US
Marc Shiraki - San Jose CA, US
Stephen Richard Friberg - Mountain View CA, US

H01S 3/04

372 34

Systems and methods to improve the performance of nonlinear crystals in a resonant cavity are presented. A humidified purge gas is supplied to a resonant cavity of a laser based illumination source that includes a nonlinear crystal. A small amount of water vapor is added to a clean, dry purge gas to prevent excessive drying of the nonlinear crystal during storage or operation. In some embodiments, a humidity injection system includes at least two parallel flow paths. One flow path includes a humidity injector and another does not include humidity injection. The amount of water vapor added to the purge gas flow is determined at least in part by the relative flow rate between the parallel flow paths. In some embodiments, the amount of water vapor added to the purge gas flow is regulated based on a measurement of humidity in the resonant cavity.