Patent · US Expired

In-situ particle detection utilizing optical coupling

US5751422A · kind A · utility

68Cited by
11References
18Claims
0Family size

Assignee

Inventor

Key dates

Filing dateFeb 26, 1996
Grant dateMay 12, 1998
Priority date
Expiry dateFeb 26, 2016

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01N21/53
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A resonant optical cavity having a laser medium therein is positioned within a specific environment, such as a process and/or harsh environment, and a sensing region, also within the resonant optical cavity, receives light whereby particles at the sensing region affect, as by scattering, light at the sensing region. The affected light is optically collected within the specific environment and optically coupled to a processor outside the specific environment where an output is provided that is indicative of particles detected at the sensing region, including small particles having a size at least as small as about 0.05 to 10 microns. With a solid state laser medium utilized within the resonant optical cavity, the solid state laser medium is pumped by an actuator, such as a semiconductor diode laser, providing a light output that is optically coupled to the solid state laser medium. Optical coupling includes fiber optics and lenses for focusing light into and out of the fiber optics, as well as a notch filter through which scattered light is coupled to the processor, and, with the specific environment contained within a housing, an optical feedthrough is utilized to couple light thro…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.