Measuring and testing – Gas analysis – Moisture content or vapor pressure
Patent
1975-11-28
1976-10-26
Swisher, S. Clement
Measuring and testing
Gas analysis
Moisture content or vapor pressure
204 38A, 338 35, G01N 2556
Patent
active
039876764
ABSTRACT:
A relative humidity detector, is formed upon a substrate such as glass or amorphous quartz. An aluminum layer evaporated onto the substrate has a layer of Al.sub.2 O.sub.3 anodized thereover to a thickness of 5,000 to 10,000 angstroms. A gold upper metallic layer overlies an adherent layer of chromium upon the Al.sub.2 O.sub.3 to a combined thickness of 1000 Angstroms. After the substrate has been mounted onto an appropriate header, it is submerged in a water bath for about 8 to 12 hours. It is then heated at a temperature of about 120.degree. C. for 6 to 12 hours. The submersion and heating process produces an impedance variation at 1000 Hz which is linear over the relative humidity range of between zero and 100%.
In another embodiment, an electrode of gold over chromium evaporated onto a portion of the substrate forms a first electrode. A layer of aluminum evaporated over the substrate and a portion of the first electrode has a layer of Al.sub.2 O.sub.3 thereover. A layer of gold overlying an adherant layer of chromium is formed over a portion of the layer of Al.sub.2 O.sub.3. A second electrode of gold and chrome overlies an edge portion of the top gold layer, and extends away from it onto the underlying substrate. Electrical connections are made to the first and second electrodes.
REFERENCES:
patent: 3075385 (1963-01-01), Stover
patent: 3121853 (1964-02-01), Jason
patent: 3345596 (1967-10-01), Delaney
patent: 3440372 (1969-04-01), Cecil
patent: 3523244 (1970-08-01), Goodman
patent: 3540278 (1970-11-01), Diamond
patent: 3550057 (1970-12-01), Young
patent: 3683243 (1972-08-01), Rockliff
patent: 3861031 (1975-01-01), Furuichi
Storer, C. M., New Aluminum Oxide Humidity Element, (second report), Sandia Laboratories Publication SC-4667(RR), Mar. 1962.
LandOfFree
Relative humidity detector does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Relative humidity detector, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Relative humidity detector will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-178549