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US4557137A
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Photoacoustic analyzer
Assignee: Hitachi Ltd
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Filing: 1983-09-07
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Granted: 1985-12-10
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Expires: 2003-09-07
Abstract
Abstract A photoacoustic analyzer comprises an analyzing cell having a beam entrance window and including a cylindrical piezoelectric transducer element forming at least a part of the wall thereof, and a laser beam emitter emitting a laser beam directed toward and into the analyzing cell through the beam entrance window. In the photoacoustic analyzer, the ratio r/r o between the radius r of the inner side of the analyzing cell and the radius r o of the incident laser beam is selected to lie within the range of 1≦r/r o ≦8.
Inventors
- 👤 Takehiko Kitamori
- 👤 Masaaki Fujii
- 👤 Tsuguo Sawada
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 14:44
CPC Classifications
G; G01; G01N; G01N21/00; G01N21/17; G01N21/1702
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
86 words
A photoacoustic analyzer comprising an analyzing cell having a beam entrance window and including a cylindrical piezoelectric transducer element forming at least a part of the wall thereof, and beam emitting means emitting a light beam directed toward and into said analyzing cell through said beam entrance window, wherein the ratio r/r o between the radius r of the inner side of said analyzing cell and the radius r o of said incident light beam is selected to lie within the range of 1≦r/r o ≦8.
Claim 2
Dependent Claim
86 words
A photoacoustic analyzer comprising an analyzing cell having a beam entrance window and including a cylindrical piezoelectric transducer element forming at least a part of the wall thereof, and beam emitting means emitting a light beam directed toward and into said analyzing cell through said beam entrance window, wherein the ratio r/r o between the radius r of the inner side of said analyzing cell and the radius r o of said incident light beam is selected to lie within the range of 1≦r/r o ≦8.
Claim 3
Dependent Claim
17 words
A photoacoustic analyzer as claimed in claim 1, wherein said beam emitting means emits a laser beam.
Claim 4
Dependent Claim
49 words
A photoacoustic analyzer as claimed in claim 1, wherein for maximum sensitivity of said analyzing cell in which the radius r of the inner side of said analyzing cell is about 1.2 mm, the radius r o of said incident light beam is selected to be about 0.6 mm.
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) | 1988-12-09 | 1989-06-10 | 1989-12-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-12-09 | 1993-06-10 | 1993-12-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-12-09 | 1997-06-10 | 1997-12-10 | $7700.00 | Window Closed / Lapsed |