EP0588643A1
Expired / Lapsed
EP
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Thermal image detecting apparatus
Assignee: Panasonic Holdings Corp
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Filing: 1993-09-16
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Granted: —
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Expires: 2013-09-16
Abstract
Abstract An infrared sensor composed of an array of pyroelectric type heat detecting elements, a chopper, a chopper operation detecting means for detecting the operation of the chopper, a duty compensating means and a chopper failure detecting means are arranged. Thus, the actual opening and closing duty of the chopper can maintained to be uniform so as to detect a thermal image with a high degree of accuracy, and a failure of the chopper can be detected, thereby it is possible to enhance the reliability of the operation.
Inventors
- 👤 Takuo Shimada
- 👤 Isamu Okuda
- 👤 Takashi Deguchi
- 👤 Morihiro Nakayama
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-08 06:50
CPC Classifications
G; G01; G01J; G01J5/00; G01J5/02; G08; G08B; G08B13/00; G08B13/18; G08B13/189; G08B13/19; G08B13/191
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
118 words
A two-dimensional thermal image detecting apparatus comprising: an array of pyroelectric type heat detecting elements arranged one-dimensionally on a straight line; an infrared ray transmission lens integrally incorporated with the array of pyroelectric type heat detecting elements; a chopper for limiting the quantity of infrared lays incident upon said array of pyroelectric type heat detecting elements through the intermediary of said infrared ray transmission lens; a chopper operation detecting means for detecting the operation of said chopper; and a rotary shaft laid in parallel with or inclined at a predetermined angle from said straight line, whereby said array of pyroelectric type heat detecting elements is rotated about said rotary shaft so as to obtain a two-dimensional thermal image.
Claim 2
Dependent Claim
57 words
An apparatus as set forth in claim 1, wherein said chopper is composed of a shutter which blocks light and infrared rays, and said chopper operation detecting means is composed of an optical detecting element for determining whether said shutter is in an opening condition or a closing condition in accordance with the presence of light transmission.
Claim 3
Dependent Claim
77 words
An apparatus as set forth in claim 1, further comprising a duty compensating means, wherein said duty compensating means changes the opening control time and the closing control time of said chopper so as to maintain the time ratio between the opening condition and the closing condition of said chopper within a predetermined range in accordance with a signal from said chopper operation detecting means which is delivered during detection of a two-dimensional thermal image by rotation.
Claim 4
Dependent Claim
75 words
An apparatus as set forth in claim 1, further comprising a duty compensating means, wherein said chopper is driven before detection of a two-dimensional thermal image by rotation, and said duty compensating means changes the opening control time and the closing control time of said chopper so as to maintain the time ratio between the opening condition and the closing condition of said chopper in accordance with a signal from said chopper operation detecting means.
Claim 5
Dependent Claim
54 words
An apparatus as set forth in claim 1, further comprising a failure detecting means, wherein said failure detecting means detects a failure of said chopper in accordance with a signal from said chopper operation detection means, which is delivered from said chopper operation detecting means during detection of a two-dimensional thermal image by rotation.
Claim 6
Dependent Claim
50 words
An apparatus as set forth in claim 1, further comprising a failure detecting means, wherein said chopper is driven before detection of a two-dimensional thermal image by rotation, and said failure detecting means detects a failure of said chopper in accordance with a signal from said chopper operation detecting means.
References Cited (Backward Citations)
US4684804A
Cited
EP0501253A1
Cited
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