US6353224B1
Expired / Lapsed
US
⏱️ 0.0 years remaining
Millimeter wave imaging apparatus
Assignee: Qinetiq Ltd
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Filing: 1998-01-09
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Granted: 2002-03-05
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Expires: 2018-01-09
Abstract
Abstract Millimeter wave imaging apparatus for use, in articular, as an indoor security system to identify objects concealed under the clothing of a person in a background scene, including means for generating a millimetric temperature contrast between the person to be imaged and the surroundings in scene. This may be a "hot" or "cold" source for producing a flux, and a relatively smaller flux respectively, of incoherent millimeter wavelength radiation. The apparatus may also include at least one partial ellipsoid reflective enclosure for reflecting millimeter wavelength radiation emitted from the "hot" and "cold" source so as to generate non-localized and uniform illumination of the person. The enclosure may have a metallic inner surface on which a dimpled pattern may be embossed to diffuse the millimeter wavelength radiation reflected from the metallic inner surface. The apparatus also includes one or more millimeter wavelength imaging cameras for detecting the millimeter wavelength radiation at one or more millimeter wave center frequencies, which may be mounted inside or outside the reflective enclosure. An image of the objects may be generated on a television monitor from the detected radiation.
Inventors
- 👤 Gordon N Sinclair
- 👤 Alan H Lettington
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 09:12
CPC Classifications
G; G01; G01V; G01V8/00; G01V8/005; G01S; G01S13/00; G01S13/88; G01S13/887
Claims Analysis
Total Claims: 35
Claim 1
Independent Claim
118 words
Apparatus for detecting at least one object having a millimetric temperature, said at least one object situated in background surroundings having a background millimetric temperature, said apparatus comprising; means for varying the background millimetric temperature so as to generate a contrast between the background millimetric temperature and the millimetric temperature of the object, and a detector for detecting the contrast between the background millimetric temperature and the millimetric temperature of the at least one object, wherein the means for varying the background millimetric temperature comprise: an enclosure and at least one source of substantially incoherent millimetre wave radiation, the enclosure and the at least one source arranged to provide substantially uniform illumination of the at least one object.
Claim 2
Dependent Claim
118 words
Apparatus for detecting at least one object having a millimetric temperature, said at least one object situated in background surroundings having a background millimetric temperature, said apparatus comprising; means for varying the background millimetric temperature so as to generate a contrast between the background millimetric temperature and the millimetric temperature of the object, and a detector for detecting the contrast between the background millimetric temperature and the millimetric temperature of the at least one object, wherein the means for varying the background millimetric temperature comprise: an enclosure and at least one source of substantially incoherent millimetre wave radiation, the enclosure and the at least one source arranged to provide substantially uniform illumination of the at least one object.
Claim 3
Dependent Claim
23 words
The apparatus of claim 1 wherein the enclosure comprises a reflector for reflecting millimetre wavelength radiation emitted by the at least one source.
Claim 4
Dependent Claim
17 words
The apparatus of claim 2 wherein the reflector is a reflecting enclosure having a reflective inner surface.
Claim 5
Dependent Claim
13 words
The apparatus of claim 3 wherein the reflecting enclosure is a partial ellipsoid.
Claim 6
Dependent Claim
65 words
The apparatus of claim 3 wherein the reflecting enclosure is a room having at least one opening, said at least one opening having an entrance region, wherein the entrance region is coated with an emissive material having an apparent millimetric temperature substantially the same as that of the background millimetric temperature to prevent reflection of millimetre wavelength radiation from outside the enclosure into the enclosure.
Claim 7
Dependent Claim
29 words
The apparatus of claim 3 wherein the reflective inner surface is embossed with a dimpled pattern such that millimetre wavelength radiation reflected from the reflective inner surface is diffused.
Claim 8
Dependent Claim
17 words
The apparatus of claim 3 wherein the reflecting inner surface is provided by a dimpled reflective covering.
Claim 9
Dependent Claim
51 words
The apparatus of claim 1 , wherein the at least one source has an emitting surface for emitting substantially incoherent millimetre wavelength radiation, wherein the emitting surface forms part of the enclosure, such that the background surroundings and the at least one object are illuminated substantially uniformly with millimetre wavelength radiation.
Claim 10
Dependent Claim
28 words
The apparatus of claim 8 , wherein the enclosure is a cubicle having at least one side formed from the emitting surface of the at least one source.
Claim 11
Dependent Claim
32 words
The apparatus of claim 1 wherein the detection means comprise at least one millimetre wave imaging camera for detecting millimetre wavelength radiation reflected from and emitted by said at least one object.
Claim 12
Dependent Claim
24 words
The apparatus of claim 10 wherein the at least one millimetre wave imaging camera has at least one millimetre wave centre frequency of operation.
Claim 13
Dependent Claim
28 words
The apparatus of claim 11 , said at least one camera comprises at least two millimetre wave imaging cameras having substantially different millimetre wave centre frequencies of operation.
Claim 14
Dependent Claim
19 words
The apparatus of claim 10 wherein the at least one millimetre wave imaging camera is mounted outside the enclosure.
Claim 15
Dependent Claim
19 words
The apparatus of claim 10 wherein the at least one millimetre wave imaging camera is mounted within the enclosure.
Claim 16
Dependent Claim
33 words
The apparatus of claim 10 wherein the at least one millimetre wave imaging camera has an associated processor and television monitor for generating a millimetre wavelength image of said at least one object.
Claim 17
Dependent Claim
60 words
The apparatus of claim 1 wherein the at least one source comprises; a layer of emissive material, having an optical thickness t, for emitting millimetre wavelength radiation and heating means for increasing the temperature of the layer of emissive material, whereby increasing the temperature of the layer of emissive material gives rise to an increase in the background millimetric temperature.
Claim 18
Dependent Claim
15 words
The apparatus of claim 16 wherein the heating means comprise at least one heating element.
Claim 19
Dependent Claim
65 words
The apparatus of claim 17 wherein the at least one source further comprises a metal layer, wherein the metal layer and the layer of emissive material form a structure having an emissivity, ε, in the millimetre wavelength region, and wherein the optical thickness, t, of the layer of emissive material is such that the emission of millimetre wavelength radiation from said structure is substantially maximised.
Claim 20
Dependent Claim
17 words
The apparatus of claim 18 wherein the emissivity, ε, of the structure is between 0.5 and 1.0.
Claim 21
Dependent Claim
17 words
The apparatus of claim 19 wherein the emissivity, ε, of the structure is substantially equal to 1.0.
Claim 22
Dependent Claim
11 words
The apparatus of claim 19 wherein the metal layer is aluminium.
Claim 23
Dependent Claim
20 words
The apparatus of claim 16 wherein the emissive material is one of clay tiles, asbestos fire blanket and fire cement.
Claim 24
Dependent Claim
27 words
The apparatus of claim 16 wherein the at least one source further comprises insulation for reducing the emission of infrared radiation from the at least one source.
Claim 25
Dependent Claim
12 words
The apparatus of claim 23 wherein the insulation comprise a fibreglass mat.
Claim 26
Dependent Claim
51 words
The apparatus of claim 16 wherein the at least one source further comprises at least one additional metal layer for internally reflecting millimetre wavelength radiation emitted from the emissive material, such that the emission of millimetre wavelength radiation from the emitting surface of the at least one source is substantially maximised.
Claim 27
Dependent Claim
52 words
The apparatus of claim 1 , wherein the at least one source comprises; a layer of material for emitting millimetre wavelength radiation and a cooler for decreasing the temperature of the emissive material, whereby decreasing the temperature of the layer of material gives rise to a decrease in the background millimetric temperature.
Claim 28
Dependent Claim
15 words
The apparatus of claim 26 wherein the layer of material is radar absorbing material (RAM).
Claim 29
Dependent Claim
12 words
The apparatus of claim 27 wherein the cooler comprises a refrigeration unit.
Claim 30
Dependent Claim
25 words
The apparatus of claim 26 , wherein the at least one source also comprises a millimetre radiation transparent layer enclosing the layer of emitting material.
Claim 31
Dependent Claim
21 words
The apparatus of claim 1 , wherein the at least one source Gunn diode for emitting substantially incoherent millimetre wavelength radiation.
Claim 32
Dependent Claim
27 words
The apparatus of claim 1 , wherein the at least one source comprises a plurality of gas discharge noise sources for emitting substantially incoherent millimetre wavelength radiation.
Claim 33
Dependent Claim
21 words
The apparatus of claim 30 , and further comprising at least one optical element for diffusing the emitted millimetre wavelength radiation.
Claim 34
Dependent Claim
64 words
constructed and adapted to be used in the millimetre wave imaging apparatus of claim 1 comprising; a layer of emissive material, having an optical thickness t, for emitting millimetre wavelength radiation; and a heater for increasing the temperature of the layer of emissive material, whereby increasing the temperature of the layer of emissive material gives rise to an increase in the background millimetric temperature.
Claim 35
Dependent Claim
64 words
The source of claim 33 , wherein the at least one source further comprises a metal layer, the metal layer and the layer of emissive material forming a structure having an emissivity, ε, in the millimetre wavelength region, wherein the optical thickness, t, of the layer of emissive material is such that the emission of millimetre wavelength radiation from said structure is substantially maximised.
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) | 2005-03-04 | 2005-09-03 | 2006-03-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2009-03-04 | 2009-09-03 | 2010-03-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2013-03-04 | 2013-09-03 | 2014-03-05 | $7700.00 | Window Closed / Lapsed |