Patent EP0365863A2 successfully refreshed from Google Patents.
US3591810A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Temperature monitoring apparatus using a photochromic heat sensor
Assignee: Hawker Siddeley Dynamics Ltd
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Filing: 1969-04-15
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Granted: 1971-07-06
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Expires: 1989-04-15
Abstract
Abstract A temperature sensor is described in which the temperatureresponsive element is a photochromic compound. This compound, in film form, is irradiated by activating and monitoring radiation of appropriate wavelengths. The activating radiation induces a change in the extent to which the monitoring radiation is transmitted by the photochromic compound. The amount of this change is temperature-dependent, thereby giving the required temperature responsiveness.
Inventors
- 👤 Geoffrey Jackson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 11:28
CPC Classifications
G; G01; G01K; G01K11/00; G01K11/12; G01K11/16
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
19 words
A device according to claim 1, further comprising optical filter means disposed between the source and the photochromic sensor.
Claim 2
Dependent Claim
17 words
A device according to claim 1 wherein the activating and monitoring radiation is of the same wavelength.
Claim 3
Dependent Claim
19 words
A device according to claim 1, wherein the monitoring radiation is of a wavelength different from the activating radiation.
Claim 4
Dependent Claim
24 words
A device according to claim 4, wherein the intensity of the activating radiation is variable, without variation in the intensity of the monitoring radiation.
Claim 5
Dependent Claim
22 words
A device according to claim 1 wherein the photochromic sensor has a reflecting backing and the photosensitive detector receives radiation reflected thereby.
Claim 6
Dependent Claim
20 words
A device according to claim 1, further comprising an optical system for directing the source radiation on the photochromic sensor.
Claim 7
Dependent Claim
20 words
A device according to claim 1, further comprising optical filter means disposed between the photochromic sensor and the photosensitive detector.
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) | 1974-07-05 | 1975-01-04 | 1975-07-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-07-05 | 1979-01-04 | 1979-07-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-07-05 | 1983-01-04 | 1983-07-06 | $7700.00 | Window Closed / Lapsed |