US5041723A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Infrared ray detector with multiple optical filters
Assignee: Horiba Ltd
•
Filing: 1990-09-28
•
Granted: 1991-08-20
•
Expires: 2010-09-28
Abstract
Abstract An infrared ray detector assembly for detecting a plurality of components such as hydrocarbons, CO 2 and CO gases includes a housing member having a hollow interior and a portion transmissible to infrared rays and a holder member mounted within the hollow interior and having a plurality of separate compartments. An infrared detector is mounted in each compartment, and an optical filter is mounted over each compartment, abutting adjacent filters to respectively limit the wavelength band to each infrared detector, each optical filter having a substrate of approximately the same material and thickness.
Inventors
- 👤 Masahiko Ishida
- 👤 Toshikazu Ohnishi
- 👤 Syuji Takada
- 👤 Kimio Miyatake
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 20:31
CPC Classifications
G; G01; G01N; G01N21/00; G01N21/17; G01N21/25; G01N21/31; G01N21/35; G01N21/3504; G01N2021/3129; G01N2021/3137; G01N21/314; G01N2021/3166
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
122 words
An infrared ray detector assembly for detecting a plurality of components, including HC, CO 2 , and CO, comprising: a holder member; infrared detectors mounted on the holder member corresponding to each component to be detected; optical filters mounted across each infrared detector having a design wavelength and a half-bandwidth as follows: Optical filter for use in HC: Central wavelength: 3.4 μm; Half-bandwidth: 8.6% Optical filter for use in CO 2 : Central wavelength: 4.3 μm; Half-bandwidth: 4.2% Optical filter for use in CO: Central wavelength: 4.7 μm; Half-bandwidth: 8.6% Optical filter for use in the standard gas: Central wavelength: 3.8 μm; Half-bandwidth: 3.0% wherein each half-bandwidth value represents a percentage of the associated central design wavelength and can vary by ±5%.
Claim 2
Dependent Claim
122 words
An infrared ray detector assembly for detecting a plurality of components, including HC, CO 2 , and CO, comprising: a holder member; infrared detectors mounted on the holder member corresponding to each component to be detected; optical filters mounted across each infrared detector having a design wavelength and a half-bandwidth as follows: Optical filter for use in HC: Central wavelength: 3.4 μm; Half-bandwidth: 8.6% Optical filter for use in CO 2 : Central wavelength: 4.3 μm; Half-bandwidth: 4.2% Optical filter for use in CO: Central wavelength: 4.7 μm; Half-bandwidth: 8.6% Optical filter for use in the standard gas: Central wavelength: 3.8 μm; Half-bandwidth: 3.0% wherein each half-bandwidth value represents a percentage of the associated central design wavelength and can vary by ±5%.
Claim 3
Dependent Claim
24 words
The invention of claim 1 wherein each optical filter has a substrate of the same thickness, each adhered together to provide a continuous surface.
Claim 4
Dependent Claim
16 words
The invention of claim 1 further including means for regulating the temperature of the optical filters.
Claim 5
Dependent Claim
21 words
The invention of claim 1 wherein the holder member includes a series of slots, each slot supporting a different infrared detector.
Claim 6
Dependent Claim
27 words
The invention of claim 1 further including a housing member extending over the holder member, the housing member having an inner surface roughened to absorb infrared rays.
Claim 7
Dependent Claim
20 words
The invention of claim 2 wherein each substrate is formed of a material consisting of one of Si or Ge.
Claim 8
Dependent Claim
30 words
The invention of claim 3 wherein the temperature regulating means includes a thermomodule and a thermistor, the thermistor mounted on the holder member and overlapping one end of the thermomodule.
Claim 9
Dependent Claim
22 words
An infrared ray detector as set forth in claim 2, wherein all substrates composing the respective optical filters are made of Si.
Claim 10
Dependent Claim
91 words
An infrared ray detector assembly for detecting a plurality of components in automotive exhaust gases, comprising: a housing member having a hollow interior and a portion transmissible to infrared rays; a holder member mounted within the hollow interior and having a plurality of separate compartments; an infrared detector mounted in each compartment, and an optical filter mounted over each compartment to respectively limit the wavelength band to each infrared detector, each optical filter having a substrate of approximately the same thickness and abutting an optical filter extending over an adjacent compartment.
Claim 11
Dependent Claim
91 words
An infrared ray detector assembly for detecting a plurality of components in automotive exhaust gases, comprising: a housing member having a hollow interior and a portion transmissible to infrared rays; a holder member mounted within the hollow interior and having a plurality of separate compartments; an infrared detector mounted in each compartment, and an optical filter mounted over each compartment to respectively limit the wavelength band to each infrared detector, each optical filter having a substrate of approximately the same thickness and abutting an optical filter extending over an adjacent compartment.
Claim 12
Dependent Claim
93 words
The invention of claim 9 wherein the optical filters have a design wavelength and a half-bandwidth as follows: Optical filter for use in HC: Design wavelength: 3.4 μm; Half-bandwidth: 8.6% Optical filter for use in CO 2 : Design wavelength: 4.3 μm; Half-bandwidth: 4.2% Optical filter for use in CO: Design wavelength: 4.7 μm; Half-bandwidth: 8.6% Optical filter for use in the standard gas: Design wavelength: 3.8 μm; Half-bandwidth: 3.0% wherein each half-bandwidth value represents a percentage of the associated design wavelength at one-half of the peak transmittance and can vary by ±5%.
Claim 13
Dependent Claim
16 words
The invention of claim 9 further including means for regulating the temperature of the optical filters.
Claim 14
Dependent Claim
18 words
The invention of claim 9 wherein the housing member has an inner surface roughened to absorb infrared rays.
Claim 15
Dependent Claim
20 words
The invention of claim 9 wherein each substrate is formed of a material consisting of one of Si or Ge.
Claim 16
Dependent Claim
30 words
The invention of claim 11 wherein the temperature regulating means includes a thermomodule and a thermistor, the thermistor mounted on the holder member and overlapping one end of the thermomodule.
Claim 17
Dependent Claim
168 words
In an infrared ray detector, in which four infrared ray detecting elements are arranged to receive infrared rays through a window in a sealed case, the improvement comprising: respective optical filters transmissible to infrared rays having respective wavelength bands absorbed by an HC gas, a CO 2 gas, a CO gas, and a standard gas are arranged between the respective windows and said respective infrared ray detecting elements; a central wavelength and a half-bandwidth of said wavelength bands of infrared rays transmissible through the respective optical filters and set within a range of the following standard values ±5%: Optical filter for use in HC: Central wavelength: 3.4 μm; Half-bandwidth: 8.6% Optical filter for use in CO 2 : Central wavelength: 4.3 μm; Half-bandwidth: 4.2% Optical filter for use in CO: Central wavelength: 4.7 μm; Half-bandwidth: 8.6% Optical filter for use in the standard gas: Central wavelength: 3.8 μm; Half-bandwidth: 3.0% wherein each half-bandwidth value represents a percentage of the associated central wavelength at one-half of the peak transmittance.
Claim 18
Dependent Claim
168 words
In an infrared ray detector, in which four infrared ray detecting elements are arranged to receive infrared rays through a window in a sealed case, the improvement comprising: respective optical filters transmissible to infrared rays having respective wavelength bands absorbed by an HC gas, a CO 2 gas, a CO gas, and a standard gas are arranged between the respective windows and said respective infrared ray detecting elements; a central wavelength and a half-bandwidth of said wavelength bands of infrared rays transmissible through the respective optical filters and set within a range of the following standard values ±5%: Optical filter for use in HC: Central wavelength: 3.4 μm; Half-bandwidth: 8.6% Optical filter for use in CO 2 : Central wavelength: 4.3 μm; Half-bandwidth: 4.2% Optical filter for use in CO: Central wavelength: 4.7 μm; Half-bandwidth: 8.6% Optical filter for use in the standard gas: Central wavelength: 3.8 μm; Half-bandwidth: 3.0% wherein each half-bandwidth value represents a percentage of the associated central wavelength at one-half of the peak transmittance.
Claim 19
Dependent Claim
58 words
An infrared ray detector as set forth in claim 15, wherein all substrates of said respective optical filters have the same thickness and are adhered to each other at respective end faces, to form one continuous surface, and said respective optical filters are fixedly mounted on a holder in which the respective infrared ray detecting elements are housed.
References Cited (Backward Citations)
JPS5017276A
Cited
JPS604110A
Cited
US4678914A
Cited
US4771176A
Cited
JPS6448637A
Cited
US4914719A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-08-19 | 1995-02-18 | 1995-08-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-08-19 | 1999-02-18 | 1999-08-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-08-19 | 2003-02-18 | 2003-08-20 | $7700.00 | Window Closed / Lapsed |