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US4572900A
Expired / Lapsed
US
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Organic semiconductor vapor sensing method
Assignee: United States Department of the Navy
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Filing: 1984-04-25
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Granted: 1986-02-25
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Expires: 2004-04-25
Abstract
Abstract A method and apparatus to automatically compensate for temperature variation in a vapor detection system. In one embodiment, two identical organic semiconductor film sensors in close thermal contact with each other are used in the feedback circuit of an inverting amplifier supplied by constant voltage. One of the sensors is isolated from vapor exposure to act as a reference for the other sensor which is used for vapor sampling. The output of the inverting amplifier provides an indication of the presence and relative concentration of vapor exposure. Variation in sample sensor resistance due to a change in temperature is accompanied by the same corresponding change in the reference sensor, which stabilizes the ratio of the feedback circuit resistances and therefore the gain of the inverting amplifier to exactly compensate for the temperature induced resistance variations automatically.
Inventors
- 👤 Henry Wohltjen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 12:37
CPC Classifications
G; G01; G01N; G01N27/00; G01N27/02; G01N27/04; G01N27/12; G01N27/122; G01N27/125; G01N27/126
Claims Analysis
Total Claims: 40
Claim 1
Independent Claim
112 words
A vapor detection apparatus having automatic temperature compensation comprising: vapor sensitive variable electric resistance means for detecting the presence of vapor; reference electrical resistance means having a temperature coefficient corresponding to said vapor sensitive resistance means for balancing thermal variation of said vapor sensitive resistance means; coupling means thermally coupling said vapor sensitive resistance means and said reference resistance means; electric potential means for generating a first current signal through one of said resistance means; and electrical current-to-potential converting means for generating a second current signal through the other of said reistance means and developing an electric output potential inversely proportional to said first current signal combined with said second current signal.
Claim 2
Dependent Claim
112 words
A vapor detection apparatus having automatic temperature compensation comprising: vapor sensitive variable electric resistance means for detecting the presence of vapor; reference electrical resistance means having a temperature coefficient corresponding to said vapor sensitive resistance means for balancing thermal variation of said vapor sensitive resistance means; coupling means thermally coupling said vapor sensitive resistance means and said reference resistance means; electric potential means for generating a first current signal through one of said resistance means; and electrical current-to-potential converting means for generating a second current signal through the other of said reistance means and developing an electric output potential inversely proportional to said first current signal combined with said second current signal.
Claim 3
Dependent Claim
22 words
The vapor detection apparatus according to claim 1, wherein said vapor sensitive variable electrical resistance means comprises an organic semiconductor film sensor.
Claim 4
Dependent Claim
28 words
The vapor detection apparatus according to claim 2, wherein said reference electrical resistance means comprises a vapor sensitive organic film sensor with isolation means for blocking vapor contact.
Claim 5
Dependent Claim
26 words
The vapor detection apparatus according to claim 3, wherein said organic film sensors each comprise an organic semiconductor film deposited onto an interdigitated surface conductivity cell.
Claim 6
Dependent Claim
18 words
The vapor detection apparatus according to claim 4, wherein said electric potential means comprises a constant voltage source.
Claim 7
Dependent Claim
18 words
The vapor detection apparatus according to claim 5, wherein said electric potential means comprises a constant voltage regulator.
Claim 8
Dependent Claim
17 words
The vapor detection apparatus according to claim 6, wherein said electrical current-to-potentital means comprises an operational amplifier.
Claim 9
Dependent Claim
16 words
The vapor detection apparatus according to claim 7, wherein said coupling means comprises a heat sink.
Claim 10
Dependent Claim
22 words
The vapor detection apparatus according to claim 8, wherein said heat sink comprises a common substrate for said organic semiconductor film sensors.
Claim 11
Dependent Claim
18 words
The vapor detection apparatus according to claim 9, wherein said isolation means comprises an inert passivating film covering.
Claim 12
Dependent Claim
22 words
The vapor detection apparatus according to claim 10, further comprising electric potential sensing means for determining the level of said potential output.
Claim 13
Dependent Claim
17 words
The vapor detection apparatus according to claim 11, wherein said electric potential sensing means comprises a voltmeter.
Claim 14
Dependent Claim
28 words
The vapor sensing apparatus according to claim 12, wherein said organic semiconductor films each comprise a metal-phthalocyanine film wherein one constituent of said metal-phthalocyanine film is a metal.
Claim 15
Dependent Claim
25 words
The vapor sensing apparatus according to claim 13, wherein said metal is selected from the group consisting of copper, nickel, iron, lead, manganese and cobalt.
Claim 16
Dependent Claim
13 words
The vapor sensing apparatus according to claim 13, wherein said metal comprises iron.
Claim 17
Dependent Claim
129 words
A temperature compensated vapor detection circuit for a vapor analysis system comprising: a voltage regulator circuit having a regulated output: an operational amplifier having a negative input, a positive input connected to ground potential and an amplifier output having an electric potential output inversely proportional to current fed into said negative input; a vapor sensor having electrical resistance proportional to vapor exposure connected between said regulated output and said negative input; an electrical reference resistance having a temperature coefficient corresponding to said vapor sensor connected between said amplifier output and said negative input; a thermal coupling thermally linking said reference resistance to said vapor sensor: a vapor isolation barrier for protecting said reference resistance from exposure to vapor; and an electric potential output sensor connected to said amplifier output.
Claim 18
Dependent Claim
129 words
A temperature compensated vapor detection circuit for a vapor analysis system comprising: a voltage regulator circuit having a regulated output: an operational amplifier having a negative input, a positive input connected to ground potential and an amplifier output having an electric potential output inversely proportional to current fed into said negative input; a vapor sensor having electrical resistance proportional to vapor exposure connected between said regulated output and said negative input; an electrical reference resistance having a temperature coefficient corresponding to said vapor sensor connected between said amplifier output and said negative input; a thermal coupling thermally linking said reference resistance to said vapor sensor: a vapor isolation barrier for protecting said reference resistance from exposure to vapor; and an electric potential output sensor connected to said amplifier output.
Claim 19
Dependent Claim
24 words
The vapor detection circuit according to claim 16, wherein said vapor sensor comprises an organic semiconductor film deposited onto an interdigitated surface conductivity cell.
Claim 20
Dependent Claim
24 words
The vapor detection circuit according to claim 17, where said reference resistance comprises an organic semiconductor film deposited onto an interdigitated surface conductivity cell.
Claim 21
Dependent Claim
23 words
The vapor detection circuit according to claim 18, wherein said vapor isolation barrier comprises an inert passivating film coating over said reference resistance.
Claim 22
Dependent Claim
24 words
The vapor detection apparatus according to claim 19, wherein said thermal coupling comprises a common substrate for said vapor sensor and said reference resistance.
Claim 23
Dependent Claim
17 words
The vapor detection apparatus according to claim 20, wherein said electrical potential output sensor comprises a voltmeter.
Claim 24
Dependent Claim
28 words
The vapor detection circuit according to claim 21, wherein said organic semiconductor films each comprise a metal-phthalocyanine film wherein one constituent of said metal-phthalocyanine film is a metal.
Claim 25
Dependent Claim
25 words
The vapor detection circuit according to claim 22, wherein said metal is selected from the group consisting of copper, nickel, iron, lead, manganese and cobalt.
Claim 26
Dependent Claim
13 words
The vapor detection circuit according to claim 22, wherein said metal comprises iron.
Claim 27
Dependent Claim
129 words
A temperature compensated vapor detection circuit for a vapor analysis system comprising: a voltage regulator circuit having a regulated output; an operational amplifier having a negative input, a positive input connected to ground potential and an amplifier output having an electric potential output inversely proportional to current fed into said negative input; a vapor sensor having electrical resistance proportional to vapor exposure connected between said amplifier output and said negative input; an electrical reference resistance having a temperature coefficient corresponding to said vapor sensor connected between said regulated output and said negative input; a thermal coupling thermally linking said reference resistance to said vapor sensor; a vapor isolation barrier for protecting said reference resistance from exposure to vapor; and an electric potential output sensor connected to said amplifier output.
Claim 28
Dependent Claim
129 words
A temperature compensated vapor detection circuit for a vapor analysis system comprising: a voltage regulator circuit having a regulated output; an operational amplifier having a negative input, a positive input connected to ground potential and an amplifier output having an electric potential output inversely proportional to current fed into said negative input; a vapor sensor having electrical resistance proportional to vapor exposure connected between said amplifier output and said negative input; an electrical reference resistance having a temperature coefficient corresponding to said vapor sensor connected between said regulated output and said negative input; a thermal coupling thermally linking said reference resistance to said vapor sensor; a vapor isolation barrier for protecting said reference resistance from exposure to vapor; and an electric potential output sensor connected to said amplifier output.
Claim 29
Dependent Claim
24 words
The vapor detection circuit according to claim 25, wherein said vapor sensor comprises an organic semiconductor film deposited onto an interdigitated surface conductivity cell.
Claim 30
Dependent Claim
24 words
The vapor detection circuit according to claim 26, wherein said reference resistance comprises an organic semiconductor film deposited onto an interdigitated surface conductivity cell.
Claim 31
Dependent Claim
23 words
The vapor detection circuit according to claim 27, wherein said vapor isolation barrier comprises an inert passivating film coating over said reference resistance.
Claim 32
Dependent Claim
24 words
The vapor detection apparatus according to claim 28, wherein said thermal coupling comprises a common substrate for said vapor sensor and said reference resistance.
Claim 33
Dependent Claim
16 words
The vapor detection apparatus according to claim 29, wherein electrical potential output sensor comprises a voltmeter.
Claim 34
Dependent Claim
28 words
The vapor detection circuit according to claim 30, wherein said organic semiconductor films each comprise a metal-phthalocyanine film wherein one constituent of said metal-phthalocyanine film is a metal.
Claim 35
Dependent Claim
25 words
The vapor detection circuit according to claim 31, wherein said metal is selected from the group consisting of copper, nickel, iron, lead, manganese and cobalt.
Claim 36
Dependent Claim
14 words
The vapor detection circuit according to the claim 31, wherein said metal comprises iron.
Claim 37
Independent Claim
126 words
A method of vapor detection having automatic temperature compensation comprising: selecting a vapor sensitive variable electrical resistance means for detecting the presence of vapor; selecting a reference electrical resistance means having a temperature coefficient corresponding to said vapor sensitive resistance means, isolation from vapor contact and thermally coupled to said vapor sensitive resistance means; generating a first current signal through one of said resistance means with the application of a constant electric potential: generating a second current signal through the other of said resistance means with the application of an electric output potential proportional to said first current signal combined with said second signal; converting said first current signal combined with said second current signal into said electric output potential; and measuring said electric potential output.
Claim 38
Independent Claim
126 words
A method of vapor detection having automatic temperature compensation comprising: selecting a vapor sensitive variable electrical resistance means for detecting the presence of vapor; selecting a reference electrical resistance means having a temperature coefficient corresponding to said vapor sensitive resistance means, isolation from vapor contact and thermally coupled to said vapor sensitive resistance means; generating a first current signal through one of said resistance means with the application of a constant electric potential: generating a second current signal through the other of said resistance means with the application of an electric output potential proportional to said first current signal combined with said second signal; converting said first current signal combined with said second current signal into said electric output potential; and measuring said electric potential output.
Claim 39
Dependent Claim
39 words
A method of vapor detection according to claim 34 wherein the step of selecting said vapor sensitive resistance means comprises the step of selecting said vapor sensitive resistance means from the class of vapor sensitive organic semiconductor film resistances.
Claim 40
Dependent Claim
56 words
A method of vapor detection according to claim 35, wherein the step of selecting said reference resistance means comprises the steps of: selecting said reference means from the class of vapor sensitive organic film resistance; isolating said reference resistance means from vapor contact; and coupling said reference resistance means to said vapor sensitive resistance means thermally.
References Cited (Backward Citations)
US4112356A
Cited
US4381922A
Cited
US4217544A
Cited
JPS55149834A
Cited
JPS55159146A
Cited
FR2460480A1
Cited
US4361802A
Cited
GB2077437A
Cited
US4350660A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-02-24 | 1989-08-26 | 1990-02-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-02-24 | 1993-08-26 | 1994-02-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-02-24 | 1997-08-26 | 1998-02-25 | $7700.00 | Window Closed / Lapsed |