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US4948964A Expired / Lapsed US ⏱️ 0.0 years remaining

Artificial target for automatic gain normalization

Assignee: Raytheon Co
•
Filing: 1988-01-14
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Granted: 1990-08-14
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Expires: 2008-01-14
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Abstract

Abstract The disclosure relates to a system for on-line normalization of the outputs of all of the detector elements of an infrared detector wherein, during the retrace period of the scanning mirror, infrared energy from a controlled thermoelectric source is reflected first from a high reflectivity sector of a rotating mirror and then from a relatively low reflectivity sector of the rotating mirror onto the detector. The detector output for the high and low reflectivity input signals is analyzed on a channel by channel basis by software controlled hardware and the gain of each channel is then adjusted in response thereto by the software controlled hardware individually. In this manner, each channel is caused to provide the same output for an identical input thereto.

Inventors

  • 👤 Mark A. Gohlke

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-26 18:22
CPC Classifications
H; H04; H04N; H04N25/00; H04N25/60; H04N25/67; H04N25/671; H04N25/673; G; G01; G01J; G01J5/00; G01J5/02; G01J5/08; G01J5/0813; G01J5/0816; G01J5/52; G01J5/53; H04N25/20; H04N25/21

Claims Analysis

Total Claims: 20
Claim 1
Independent Claim 160 words
A gain normalization system for an infrared detector comprising: (a) an infrared detector array composed of a plurality of infrared detector elements, each element providing an electrical output parameter corresponding to the energy level of an infrared input applied thereto; (b) means for applying an identical signal of a first energy level and then an identical signal of a second energy level different from said first energy level to each of said detector elements; and (c) adjusting means responsive to the electrical outputs of all of said detector elements to individually adjust the values of the output parameters from each of said detector elements; wherein said means for applying comprises a controllable uniform temperature source and means for successively reflecting a first predetermined magnitude of the energy from said source onto said detector elements followed by reflecting a second predetermined magnitude of the energy from said source onto said detector elements, said second magnitude being different from said first magnitude.
Claim 2
Dependent Claim 160 words
A gain normalization system for an infrared detector comprising: (a) an infrared detector array composed of a plurality of infrared detector elements, each element providing an electrical output parameter corresponding to the energy level of an infrared input applied thereto; (b) means for applying an identical signal of a first energy level and then an identical signal of a second energy level different from said first energy level to each of said detector elements; and (c) adjusting means responsive to the electrical outputs of all of said detector elements to individually adjust the values of the output parameters from each of said detector elements; wherein said means for applying comprises a controllable uniform temperature source and means for successively reflecting a first predetermined magnitude of the energy from said source onto said detector elements followed by reflecting a second predetermined magnitude of the energy from said source onto said detector elements, said second magnitude being different from said first magnitude.
Claim 3
Dependent Claim 27 words
A system as set forth in claim 1 wherein said means for successively reflecting comprises a movable mirror having two sectors, each sector having a different reflectivity.
Claim 4
Dependent Claim 44 words
A system as set forth in claim 1, further including a scanning mirror for transmitting an infrared scene onto said detector elements, said scanning mirror having a scanning period and a retrace period, said means for applying being operable only during said retrace period.
Claim 5
Dependent Claim 44 words
A system as set forth in claim 2, further including a scanning mirror for transmitting an infrared scene onto said detector elements, said scanning mirror having a scanning period and a retrace period, said means for applying being operable only during said retrace period.
Claim 6
Dependent Claim 32 words
A system as set forth in claim 1 wherein said adjusting means to adjust said electrical outputs further includes means responsive to said electrical outputs to control said uniform controllable temperature source.
Claim 7
Dependent Claim 32 words
A system as set forth in claim 2 wherein said adjusting means to adjust said electrical outputs further includes means responsive to said electrical outputs to control said uniform controllable temperature source.
Claim 8
Dependent Claim 32 words
A system as set forth in claim 3 wherein said adjusting means to adjust said electrical outputs further includes means responsive to said electrical outputs to control said uniform controllable temperature source.
Claim 9
Dependent Claim 32 words
A system as set forth in claim 4 wherein said adjusting means to adjust said electrical outputs further includes means responsive to said electrical outputs to control said uniform controllable temperature source.
Claim 10
Dependent Claim 41 words
A system as set forth in claim 1 further including microprocessor means responsive to the temperature of said controllable uniform temperature source and the temperature of said means for reflecting to control operation of said means responsive to the electrical outputs.
Claim 11
Dependent Claim 41 words
A system as set forth in claim 2 further including microprocessor means responsive to the temperature of said controllable uniform temperature source and the temperature of said means for reflecting to control operation of said means responsive to the electrical outputs.
Claim 12
Dependent Claim 41 words
A system as set forth in claim 3 further including microprocessor means responsive to the temperature of said controllable uniform temperature source and the temperature of said means for reflecting to control operation of said means responsive to the electrical outputs.
Claim 13
Dependent Claim 41 words
A system as set forth in claim 4 further including microprocessor means responsive to the temperature of said controllable uniform temperature source and the temperature of said means for reflecting to control operation of said means responsive to the electrical outputs.
Claim 14
Dependent Claim 41 words
A system as set forth in claim 5 further including microprocessor means responsive to the temperature of said controllable uniform temperature source and the temperature of said means for reflecting to control operation of said means responsive to the electrical outputs.
Claim 15
Dependent Claim 41 words
A system as set forth in claim 6 further including microprocessor means responsive to the temperature of said controllable uniform temperature source and the temperature of said means for reflecting to control operation of said means responsive to the electrical outputs.
Claim 16
Dependent Claim 41 words
A system as set forth in claim 7 further including microprocessor means responsive to the temperature of said controllable uniform temperature source and the temperature of said means for reflecting to control operation of said means responsive to the electrical outputs.
Claim 17
Dependent Claim 41 words
A system as set forth in claim 8 further including microprocessor means responsive to the temperature of said controllable uniform temperature source and the temperature of said means for reflecting to control operation of said means responsive to the electrical outputs.
Claim 18
Dependent Claim 82 words
A gain normalization system for an infrared detector comprising: (a) an infrared detector array composed of a plurality of infrared detector elements, each element providing an electrical output parameter corresponding to the energy level of an infrared input applied thereto; (b) thermal source means for providing predetermined infrared radiations; and (c) means responsive to said infrared radiations for consecutively providing both a first reference signal and then a second reference signal different from said first reference signal to said infrared detector array.
Claim 19
Dependent Claim 82 words
A gain normalization system for an infrared detector comprising: (a) an infrared detector array composed of a plurality of infrared detector elements, each element providing an electrical output parameter corresponding to the energy level of an infrared input applied thereto; (b) thermal source means for providing predetermined infrared radiations; and (c) means responsive to said infrared radiations for consecutively providing both a first reference signal and then a second reference signal different from said first reference signal to said infrared detector array.
Claim 20
Dependent Claim 31 words
A gain normalization system as set forth in claim 17 wherein said means responsive to said infrared radiations is a movable mirror having two sectors, each sector having a different reflectivity.

References Cited (Backward Citations)

US3576944A Cited
GB1347477A Cited
GB1273707A Cited
US3895182A Cited
US3971886A Cited
US4225883A Cited
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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) 1993-08-13 1994-02-12 1994-08-14 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1997-08-13 1998-02-12 1998-08-14 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2001-08-13 2002-02-12 2002-08-14 $7700.00 Window Closed / Lapsed

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