Fiber optic device for sensing the presence of a gas

Patent · Tue Jan 13 04:00:00 EST 1998

OSTI ID:570446

Benson, D K; Bechinger, C S; Tracy, C E

A fiber-optic device for sensing the presence of a gas in an environment is provided. The device comprises a light source for directing a light beam to a layer system having a first surface and a second surface opposite the first surface. The first surface is exposable to the light beam and the second surface is exposable to the environment. A first light portion encounters and reflects from the first surface at an angle of incidence free from optical wave guide resonance phenomenon and the second light portion encounters and reflects from the first surface at an angle of incidence enabling an optical wave guide resonance phenomenon. The layer system is selected to reversibly react with the gas to be detected. The reaction between the gas and the material changes the material`s optical properties and the wavelength at which the optical wave guide resonance occurs. Furthermore, a mechanism for measuring the intensity of the reflected first light portion relative to the reflected second light portion is provided with the ratio of the first and second light portions indicating the concentration of the gas presence in the environment. 5 figs.

• Research Organization: Midwest Research Institute
• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: AC36-83CH10093
• Assignee: PTO; SCA: 440800; SN: 98001912343; PA: EDB-98:029831
• Patent Number(s): US 5,708,735/A/
• Application Number: PAN: 8-624,112
• OSTI ID: 570446
• Country of Publication: United States
• Language: English

Related Subjects

44 INSTRUMENTATION
INCLUDING NUCLEAR AND PARTICLE DETECTORS
DESIGN
FIBER OPTICS
GAS ANALYSIS
MEASURING METHODS
MONITORS
OPTICAL PROPERTIES
REFLECTION
VISIBLE RADIATION