US4222663A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Optical pyrometer and technique for temperature measurement
Assignee: Pirelli Tyre SpA
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Filing: 1977-08-01
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Granted: 1980-09-16
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Expires: 1997-08-01
Abstract
Abstract Apparatus for making temperature measurements where reflected energy has an adverse effect on the measured target temperature is disclosed. A pair of detectors see the same target but with the use of at least one filter so that the wavelength interval of one is contained within the other. From the output, calculations are made to correct for the errors due to the reflected energy.
Inventors
- 👤 John R. Gebhart
- 👤 Bruce E. Kinchen
- 👤 Richard R. Strange
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 11:25
CPC Classifications
G; G01; G01J; G01J5/00; G01J5/02; G01J5/08; G01J5/0801; G01J5/0802; G01J5/60; G01J5/602
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
155 words
An optical pyrometer for measuring temperature of a remote target having a lens adapted to collect the energy emitted from the target, means including a fiber optic bundle for transmitting the collected energy picked-up by said lens, a pair of detectors sensitive to both the energy emitted from the target and reflected energy having identical spectral characteristics connected to said fiber optic bundle, a filter imposed between the lens and one of said detectors for limiting the spectral range passing therethrough such that the wavelength interval is contained within the band of the wavelengths sensed by the other detector, comparator means responsive to the output of said detectors for producing an indication whenever the temperature indicated by said two detectors are identical, high speed computer means also responsive to the output of said detectors for producing an output that compensates for the presence of reflected energy by estimating the magnitude of the reflected energy component.
Claim 2
Dependent Claim
155 words
An optical pyrometer for measuring temperature of a remote target having a lens adapted to collect the energy emitted from the target, means including a fiber optic bundle for transmitting the collected energy picked-up by said lens, a pair of detectors sensitive to both the energy emitted from the target and reflected energy having identical spectral characteristics connected to said fiber optic bundle, a filter imposed between the lens and one of said detectors for limiting the spectral range passing therethrough such that the wavelength interval is contained within the band of the wavelengths sensed by the other detector, comparator means responsive to the output of said detectors for producing an indication whenever the temperature indicated by said two detectors are identical, high speed computer means also responsive to the output of said detectors for producing an output that compensates for the presence of reflected energy by estimating the magnitude of the reflected energy component.
Claim 3
Dependent Claim
72 words
Apparatus as in claim 1 wherein the computer means computes the values of the target temperature in accordance with the relationship ##EQU9## where S i is the sensitivity of the pyrometer i at wavelength λ. t b is target temperature P(t) is the monochromatic emissive power of a black body at temperature t C r is a constant t r is an estimate of the temperature of the source of reflected energy
Claim 4
Dependent Claim
11 words
Apparatus as in claim 2 wherein said detectors are silicon photodiodes.
Claim 5
Dependent Claim
21 words
Apparatus as in claim 3 wherein said silicon detectors are sensitive in the spectral range from 0.4 microns to 1.2 microns.
Claim 6
Dependent Claim
18 words
Apparatus as in claim 4 wherein said silicon detectors have a frequency response in excess of 100 kilohertz.
Claim 7
Dependent Claim
21 words
Apparatus as in claim 4 wherein said filter that passes energy in the spectral range from 0.4 microns to 0.85 microns.
Claim 8
Dependent Claim
17 words
Apparatus as in claim 6 including means for linearizing the output signal produced by said computer means.
References Cited (Backward Citations)
US3105905A
Cited
US3795918A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-09-16 | 1984-03-17 | 1984-09-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-09-16 | 1988-03-17 | 1988-09-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-09-16 | 1992-03-17 | 1992-09-16 | $7700.00 | Window Closed / Lapsed |