Patent US4769545A successfully refreshed from Google Patents.
US4769545A
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US
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Motion detector
Assignee: AMERICAN IRIS CORP
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Filing: 1986-11-26
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Granted: 1988-09-06
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Expires: 2006-11-26
Abstract
Abstract A miniature passive infrared motion detector consists of an optical system, a pyroelectric polymer film and an electronic circuit. The optical system is made of a curved Fresnel lens and an elongated wave guide having a reflective inner surface. The polymer film is also curved with the same radius as the lens and has two interdigitized electrodes on the rear surface and one uniform electrode on the front surface. The front electrode is covered with infrared absorbent material. The electronic circuit contains a differential amplifier and a threshold detector.
Inventors
- 👤 Jacob Fraden
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 20:48
CPC Classifications
G; G01; G01J; G01J5/00; G01J5/0022; G01J5/02; G01J5/07; G01J5/08; G01J5/0806; G08; G08B; G08B13/00; G08B13/18; G08B13/189; G08B13/19; G08B13/191; G08B13/193; G01J5/10; G01J5/34; G01J2005/345; Y; Y10; Y10S; Y10S250/00; Y10S250/01
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
151 words
A passive radiation motion detector which is capable of sensing thermally radiated energy from a moving object, comprising, in combination: a housing having an open front end; a focusing lens mounted within the front end of said housing, said focusing lens having a curved surface; a sheet of pyroelectric material positioned within said housing and having a curved surface with substantially the same radius of curvature as that of said focusing lens, said sheet of pyroelectric material being located behind said lens at a distance approximately equal to the focal length of said lens; at least one area of electrically conductive layer on one surface of said pyroelectric material forming at least one first electrode; at least one area of electrically conductive layer on the opposite surface of said pyroelectric material forming at least one second electrode; and electrical circuit means for amplifing and processing electrical signals produced at said electrodes.
Claim 2
Dependent Claim
151 words
A passive radiation motion detector which is capable of sensing thermally radiated energy from a moving object, comprising, in combination: a housing having an open front end; a focusing lens mounted within the front end of said housing, said focusing lens having a curved surface; a sheet of pyroelectric material positioned within said housing and having a curved surface with substantially the same radius of curvature as that of said focusing lens, said sheet of pyroelectric material being located behind said lens at a distance approximately equal to the focal length of said lens; at least one area of electrically conductive layer on one surface of said pyroelectric material forming at least one first electrode; at least one area of electrically conductive layer on the opposite surface of said pyroelectric material forming at least one second electrode; and electrical circuit means for amplifing and processing electrical signals produced at said electrodes.
Claim 3
Dependent Claim
45 words
A passive radiation motion detector as defined in claim 1, wherein said second electrode is formed of two approximately equal areas of electrically conductive material being connected to a compensating means capable of rejecting common mode signals from said areas of the said second electrode.
Claim 4
Dependent Claim
42 words
A passive radiation motion detector as defined in claim 2, wherein said areas of electrically conductive material are divided into smaller interconnected sections and the sections of the respective areas are arranged in alternating fashion on the surface of said pyroelectric material.
Claim 5
Dependent Claim
30 words
A passive radiation motion detector as defined in claim 1, wherein a thin layer of thermally absorbing material is affixed to at least a portion of one of said electrodes.
Claim 6
Dependent Claim
23 words
A passive radiation motion detector as defined in claim 1, wherein said first electrode is electrically connected to ground to provide electrostatic shielding.
Claim 7
Dependent Claim
46 words
A passive radiation motion detector as defined in claim 1, wherein said first electrode is divided into two approximately equal areas of electrically conductive material and one of these areas is electrically connected to said electronic circuit while the other area is electrically connected to ground.
Claim 8
Dependent Claim
22 words
A passive radiation motion detector as defined in claim 1, wherein said flexible sheet of pyroelectric material is made of polyvinyledene fluoride.
Claim 9
Dependent Claim
18 words
A passive radiation motion detector as defined in claim 1, wherein said focusing lens is a Fresnel lens.
Claim 10
Dependent Claim
21 words
A passive radiation motion detector as defined in claim 1, wherein said focusing lens is curved to form a cylindrical surface.
Claim 11
Dependent Claim
17 words
A passive radiation motion detector as defined in claim 1, wherein said lens is made of polyethylene.
Claim 12
Dependent Claim
26 words
A passive radiation motion detector as defined in claim 1, wherein said lens is divided into sections and each section is made of individual Fresnel lens.
Claim 13
Dependent Claim
21 words
A passive radiation motion detector as defined in claim 1, wherein said lens is formed into part of a spherical surface.
Claim 14
Dependent Claim
25 words
A passive radiation motion detector as defined in claim 12, wherein said sheet of pyroelectric material is also formed into part of a spherical surface.
Claim 15
Dependent Claim
32 words
A passive radiation motion detector as defined in claim 13, wherein said lens and said sheet of pyroelectric material are formed into two hemi-spheres facing each other and forming a ball-shaped configuration.
Claim 16
Dependent Claim
46 words
A passive radiation motion detector as defined in claim 14, wherein said second electrode is formed of two approximately equal areas of electrically conductive material, each of said areas being divided into smaller interconnected sections arranged in alternating fashion on the surface of said pyroelectric material.
Claim 17
Dependent Claim
18 words
A passive radiation motion detector as defined in claim 15, wherein said second electrode comprises a checker-board pattern.
Claim 18
Dependent Claim
18 words
A passive radiation motion detector as defined in claim 15, wherein said second electrode comprises a circular pattern.
Claim 19
Dependent Claim
36 words
A passive radiation motion detector as defined in claim 14, wherein said lens is constructed of multiple sections each of which creates its own image on a corresponding section of said hemi-spherical sheet of pyroelectric material.
Claim 20
Dependent Claim
26 words
A passive radiation motion detector as defined in claim 1, wherein said housing comprises at least one surface located off the optical axis of said lens.
Claim 21
Dependent Claim
24 words
A passive radiation motion detector as defined in claim 19, wherein said surface located off the optical axis of said lens is highly reflective.
Claim 22
Dependent Claim
136 words
A passive radiation motion detector which is capable of sensing thermally radiated energy from a moving object, comprising, in combination; a housing having an open front end; a flexible focusing lens positioned within the front end of said housing; a flexible sheet of pyroelectrical material positioned behind said focusing lens, said focusing lens and said sheet of pyroelectric material being arranged so as to form opposite sides of a cylinder having a diameter approximately equal to the focal length of said lens; a first electrode comprising an electrically conductive layer covering one surface of said pyroelectric material facing said focusing lens; a second electrode comprising two approximately equal areas of electrically conductive material arranged on the opposite side of said pyroelectric material; and electrical circuit means for amplifying and processing electrical signals produced at said electrodes.
Claim 23
Dependent Claim
136 words
A passive radiation motion detector which is capable of sensing thermally radiated energy from a moving object, comprising, in combination; a housing having an open front end; a flexible focusing lens positioned within the front end of said housing; a flexible sheet of pyroelectrical material positioned behind said focusing lens, said focusing lens and said sheet of pyroelectric material being arranged so as to form opposite sides of a cylinder having a diameter approximately equal to the focal length of said lens; a first electrode comprising an electrically conductive layer covering one surface of said pyroelectric material facing said focusing lens; a second electrode comprising two approximately equal areas of electrically conductive material arranged on the opposite side of said pyroelectric material; and electrical circuit means for amplifying and processing electrical signals produced at said electrodes.
Claim 24
Dependent Claim
31 words
A passive radiation motion detector as defined in claim 21, wherein at least one wall member is positioned at an end of said cylinder, said wall member having a reflective surface.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-09-06 | 1992-03-07 | 1992-09-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-09-06 | 1996-03-07 | 1996-09-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-09-06 | 2000-03-07 | 2000-09-06 | $7700.00 | Window Closed / Lapsed |