Micromachined integrated opto-flow gas/liquid sensor
AssigneeHoneywell Inc.
InventorsUlrich Bonne, Barrett E. Cole, Robert E. Higashi
Life of this patent
Estimating the term…
Abstract
A micromachined integrated opto-fluidic or opto-acoustic sensor having a rapidly intensity-varying or pulsing light source, an interference filter, a gas cavity, which may or may not be an optical and/or acoustic resonator tuned to a particular wavelength of light, or sound frequency, into which the detected gas can diffuse into via a filter, and a fluidic or pressure sensor to detect the heating and cooling, and the resulting expansion and contraction of the gas due to the absorption of light at the particular wavelength by the specific gas being detected. The presence of other gases is inferred from the detected gas.
Claims27
A micromachined integrated gas/liquid sensor comprising:
- a wafer;
- a light source formed on said wafer;
- a layer formed on said wafer;
- an optical filter formed on said layer;
- a cavity formed on said layer;
- a flow sensor formed proximate to said cavity;
- and
- a porous filter formed on said cavity.
A micromachined integrated circuit gas/liquid sensor comprising:
- a first layer;
- a set of microemitters formed on a first surface of said first layer;
- a second layer;
- a narrow band pass filter for a first wavelength formed on a first surface of said second layer;
- a third layer;
- a fourth layer having a first surface adjacent to a first surface of said third layer, wherein said third and fourth layers have central portions removed to form a cavity;
- a channel formed in at least one first surface of said third and fourth layers, from the cavity to an outer edge of said third and fourth layers;
- a detector formed in said channel;
- a porous filter layer formed on a second surface of said fourth layer;
- and
- wherein:
- the first surface of said first layer is adjacent to a second surface of said second layer;
- and
- the first surface of said second layer is adjacent to a second surface of said third layer.
Means for sensing a gas or liquid, comprising:
- means for providing radiation;
- means for filtering radiation, proximate to said means for providing radiation;
- means for containing the gas or liquid, proximate to said means for filtering radiation;
- first means for permitting the gas or liquid to enter or leave said means for containing the gas or liquid, proximate to said means for containing the gas or liquid;
- second means for permitting the gas or liquid to enter or leave said means for containing the gas or liquid, proximate to said means for containing the gas or liquid;
- and
- means for detecting a rate of flow of the gas or liquid in or out of said means for containing the gas or liquid, proximate to said second means for permitting the gas or liquid to enter or leave means for containing the gas or liquid;
- and
- wherein:
- said means for filtering radiation is a narrow band pass filter for passing radiation at a first wavelength;
- radiation from said means for providing radiation has a varying intensity;
- the gas or liquid having an absorption of radiation at the first wavelength will vary in temperature, pressure, and volume, in that order, due to absorption of radiation having a varying intensity;
- and
- said means for detecting a rate of flow of the gas or liquid in or out of said means for containing the gas or liquid, will detect a variation in volume of the gas or liquid in said means for containing the gas or liquid .
Dependencies are inferred from the claim text.