Sohrab N Zarrabian

6785002, Aug 31, 2004

Mar 16, 2001

09/810828

Sohrab Zarrabian - Santa Rosa CA
Fred J. Van Milligen - Santa Rosa CA
Kenneth P. Rosenberg - Windsor CA
John D. Sonderman - Santa Rosa CA

Optical Coating Laboratory, Inc. - Santa Rosa CA

G01B 902

356454

An optical spectrometer uses a tapered Fabry-Perot type variable optical filter in conjunction with an optical detector array. The filter can be a long-pass, short-pass, or narrow bandpass filter. The stability of the variable optical filter allows high resolution, depending on the number and spacing of the detectors used. In a further embodiment, signal-processing techniques are used to enhance the resolution of the spectrometer beyond the measured response.

7581877, Sep 1, 2009

May 25, 2007

11/805925

Sohrab Zarrabian - Gaithersburg MD, US

G01N 25/02

374 16, 374 18, 374 20, 73 232, 73 2504

A new method and apparatus is described for measurement of the dew point, and thus the vapor pressure of various gases and gas mixtures. In this method an optical element which is exposed to a gas atmosphere is cooled while its temperature is being monitored. At the same time an optical signal is sent through the back of the optical element. The optical signal goes through internal reflections. As soon as dew forms on the surface of the element, the optical signal will exhibit selective absorption due to the interaction of the evanescent tail of the optical signal and based on the chemical nature of the condensate. This invention can also be used to characterize condensable content of gas mixtures. The method allows for the spectral characterization and determination of the condensed vapor. It offers several advantages over existing methods.

61066761, Aug 22, 2000

Apr 16, 1998

9/061578

Robert Terry - Livermore CA
Kevin Gibbons - Benicia CA
Sohrab Zarrabian - Santa Rosa CA

The BOC Group, Inc. - Murray Hill NJ

C23C 1434

20419213

The present invention is a cascade control system for reactive sputtering deposition. A first control loop modifies the power supply in order to keep a monitored value nearly constant. This first control loop can be done relatively quickly. A second control loop monitors a second measure parameter in order to control the reactive gas flow to the system. In a preferred embodiment, the slower control loop is used to maintain a relatively constant power at the power supply.

20210396660, Dec 23, 2021

Sep 3, 2021

17/466005

Sohrab ZARRABIAN - Gaithersburg MD, US

G01N 21/3554
G01N 21/25
G01N 21/3504
G01N 21/41

Systems and methods are described, and one method includes providing an optical fiber extending into a chamber with a volume of the gas; passing an optical beam, from an optical source, through the optical fiber; applying a spectral analysis to the optical beam as received after passing through the optical fiber, and outputting a corresponding spectral analysis signal; and determining, based on the output spectral analysis signal, whether a liquid is carried by the volume of the gas.

20200088631, Mar 19, 2020

Sep 13, 2019

16/570709

Sohrab Zarrabian - Gaithersburg MD, US
Sohrab ZARRABIAN - Gaithersburg MD, US

G01N 21/3554
G01N 21/25
G01N 21/3504
G01N 21/41

Systems and methods are described, and one method includes passing an optical beam through a volume of the gas to a reception surface, applying spectroanalysis to the optical beam received at the reception surface, and determining from the spectroanalysis whether a liquid is carried by the volume of the gas.