US4872759A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Sensor for gases or ions
Assignee: Siemens AG
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Filing: 1988-07-07
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Granted: 1989-10-10
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Expires: 2008-07-07
Abstract
Abstract A sensor for gases or ions with a light source, a detector and a sensor layer all of which are attached to a carrier. A thin sensor film, the absorptivity of which changes through the action of the measurement medium, is arranged on a light waveguide, the one flat side of which covers a flat end face of the light source, the end face of the carrier and a plane receiving surface of the detector. Thus, a sensitive sensor, especially for gases, is obtained in which the sensor layer, the light source and the detector form an integrated structural unit.
Inventors
- 👤 Eva-M. Stich-Baumeister
- 👤 Karl-Otto Dohnke
- 👤 Albrecht Winnacker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 07:31
CPC Classifications
G; G02; G02B; G02B6/00; G02B6/24; G02B6/42; G01; G01N; G01N21/00; G01N21/75; G01N21/77; G01N21/7703; G02B6/10; G02B6/12; G02B6/12004; G02B6/4295; G01N21/78; G01N21/783; G01N2201/00; G01N2201/06; G01N2201/062; G01N2201/0622
Claims Analysis
Total Claims: 29
Claim 1
Independent Claim
203 words
A sensor for detecting gases and ions comprising: carrier means with at least one flat surface; light source means with a light emitting surface for generating light and attached to the carrier means so that the light emitting surface of the source is in the same plane as the flat surface of the carrier; light detector means with a flat detecting surface for detecting and quantifying light falling thereon, attached to the carrier means on the side of the carrier means opposite that to which the source means is attached, the detector being mounted so that its flat detecting surface is in the same plane as the flat surface of the carrier; light wave guide means with at least one flat side mounted on the flat surface of the carrier, covering the light means, the detector means, and the flat surface with the waveguide's flat side, conveying light of various intensities from said source means to said detector means; and thin sensor layer means attached to the waveguide means on the side of the waveguide opposite to the side attached to the carrier for analyzing the gases and ions by changing its absorptivity, and thereby altering light flow through the light waveguide means.
Claim 2
Dependent Claim
203 words
A sensor for detecting gases and ions comprising: carrier means with at least one flat surface; light source means with a light emitting surface for generating light and attached to the carrier means so that the light emitting surface of the source is in the same plane as the flat surface of the carrier; light detector means with a flat detecting surface for detecting and quantifying light falling thereon, attached to the carrier means on the side of the carrier means opposite that to which the source means is attached, the detector being mounted so that its flat detecting surface is in the same plane as the flat surface of the carrier; light wave guide means with at least one flat side mounted on the flat surface of the carrier, covering the light means, the detector means, and the flat surface with the waveguide's flat side, conveying light of various intensities from said source means to said detector means; and thin sensor layer means attached to the waveguide means on the side of the waveguide opposite to the side attached to the carrier for analyzing the gases and ions by changing its absorptivity, and thereby altering light flow through the light waveguide means.
Claim 3
Dependent Claim
32 words
The sensor of claim 1 further comprising a matching layer placed between the light source means and the light waveguide means for improving the light coupling between the waveguide and the source.
Claim 4
Dependent Claim
15 words
The sensor of claim 2 wherein the matching layer is comprised of an ultraviolet-hardening adhesive.
Claim 5
Dependent Claim
32 words
The sensor of claim 1 further comprising a matching layer placed between the light waveguide means and the detector means for improving the light coupling between the waveguide means and the detector.
Claim 6
Dependent Claim
15 words
The sensor of claim 4 wherein the matching layer is comprised of an ultraviolet-hardening adhesive.
Claim 7
Dependent Claim
16 words
The sensor of claim 1 wherein the waveguide means is comprised of a III-V semiconductor compound.
Claim 8
Dependent Claim
14 words
The sensor of claim 6 wherein the waveguide is further comprised of gallium phosphide.
Claim 9
Dependent Claim
40 words
The sensor of claim 1 wherein the waveguide means is provided with a mirror surface on the side of the waveguide which is attached to the flat surface of the carrier, in the region where the waveguide contacts the carrier.
Claim 10
Dependent Claim
49 words
The sensor of claim 8 wherein the waveguide means is provided with a mirror surface on the side of the waveguide which is not attached to the flat surface of the carrier in the region where the light source contacts the waveguide and where the detector contacts the waveguide.
Claim 11
Dependent Claim
46 words
The sensor of claim 1, further comprising a second light detector means for monitoring the variability of the light source attached to the light waveguide means on the opposite side of the light waveguide and in the same region where the light source contacts the waveguide.
Claim 12
Dependent Claim
18 words
The sensor of claim 1 wherein the light source applies light to the waveguide at a oblique angle.
Claim 13
Dependent Claim
18 words
The sensor of claim 1 wherein the thin sensor layer is between 50 and 200 nanometers in thickness.
Claim 14
Dependent Claim
28 words
The sensor of claim 1 wherein the thin sensor layer comprises an optical filter with a reversible color change having at least one alkaline or acid color pigment.
Claim 15
Dependent Claim
13 words
The sensor of claim 13 wherein the color pigment contains the triphenylmethane system.
Claim 16
Dependent Claim
13 words
The sensor of claim 13 wherein the pigment contains malachite-green or crystal-violet lacton.
Claim 17
Dependent Claim
16 words
The sensor of claim 13 wherein the sensor layer contains phthaleins or sulfonephthaleins as the pigment.
Claim 18
Dependent Claim
15 words
The sensor of claim 13 where the acid color pigment contains bisphenol-A and salicic acid.
Claim 19
Dependent Claim
13 words
The sensor of claim 13 wherein the sensor layer contains p-toluidin or p-chloroanilin.
Claim 20
Dependent Claim
37 words
The sensor of claim 1 wherein the thin sensor layer comprises an optical filter with a reversible color change having at least one alkaline or acid color pigment and at least one complementary acid or alkaline compound.
Claim 21
Dependent Claim
16 words
The sensor of claim 19 wherein the pigment and compound are embedded in a matrix substance.
Claim 22
Dependent Claim
18 words
The sensor of claim 1 wherein the sensor layer is comprised at least partially of a chemosensitive material.
Claim 23
Dependent Claim
15 words
The sensor of claim 1 wherein the waveguide is between 100 and 400 micrometers thick.
Claim 24
Dependent Claim
30 words
The sensor of claim 1 wherein the light source means is a light-emitting diode, the diode and the waveguide both comprising a III-V semiconductor and being fabricated as one unit.
Claim 25
Dependent Claim
16 words
The sensor of claim 1 wherein the detector and the waveguide are fabricated as one unit.
Claim 26
Dependent Claim
12 words
The sensor of claim 1 wherein the detector contains a pn junction.
Claim 27
Dependent Claim
13 words
The sensor of claim 1 wherein the detector contains a metal-semiconductor schottky-type junction.
Claim 28
Dependent Claim
14 words
The sensor of claim 1 wherein the light waveguide is of the multimode type.
Claim 29
Dependent Claim
25 words
The sensor of claim 1 wherein two moats are etched into the III-V semiconductor material between the light source and the detector for optical insulation.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-10-09 | 1993-04-10 | 1993-10-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-10-09 | 1997-04-10 | 1997-10-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-10-09 | 2001-04-10 | 2001-10-10 | $7700.00 | Window Closed / Lapsed |