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US4967276A Expired / Lapsed US ⏱️ 0.0 years remaining

Video signal mixing device for infrared/visible integrated imaging

Assignee: Fujitsu Ltd
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Filing: 1989-05-24
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Granted: 1990-10-30
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Expires: 2009-05-24
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Abstract

Abstract A infrared/visible integrated imaging apparatus having a video signal mixing device for superimposing a visible video signal upon an infrared video signal. The mixing device has a discriminating circuit setting electrical discrimination between an infrared video signal having a level higher than a predetermined black level and having a lower than the predetermined black level. The visible video signal simultaneously output with the infrared video signal having the level higher than a predetermined black level is practically cut off with a visible video signal selecting circuit. The partially cut off video signal is then superimposed on the thermal video signal for display. The level of each of the two video signals is independently controllable.

Inventors

  • 👤 Yoshishige Murakami
  • 👤 Kanji Hirota
  • 👤 Masaaki Nakamura

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 17:25
CPC Classifications
H; H04; H04N; H04N5/00; H04N5/222; H04N5/262; H04N5/265; H04N23/00; H04N23/10; H04N23/11; H04N23/20

Claims Analysis

Total Claims: 15
Claim 1
Independent Claim 157 words
A video signal mixing device for superimposing a visible video signal output from a visible camera and an infrared video signal output from an infrared camera, both said cameras being focused on a common object, said video signal mixing device comprising: a black level discriminating circuit for discriminating a first part of said infrared video signal lower than a predetermined black level from a second part of said infrared video signal higher than said predetermined black level; a visible video selecting circuit for enabling output of said visible video signal during the presence of said first part of said infrared video signal lower than said predetermined black level, and selectively disabling output of said visible video signal during the presence of said second part of said infrared video signal higher than said predetermined black level; and a mixing circuit for superimposing said visible video signal, output from said visible video selecting circuit, and said infrared video signal.
Claim 2
Dependent Claim 157 words
A video signal mixing device for superimposing a visible video signal output from a visible camera and an infrared video signal output from an infrared camera, both said cameras being focused on a common object, said video signal mixing device comprising: a black level discriminating circuit for discriminating a first part of said infrared video signal lower than a predetermined black level from a second part of said infrared video signal higher than said predetermined black level; a visible video selecting circuit for enabling output of said visible video signal during the presence of said first part of said infrared video signal lower than said predetermined black level, and selectively disabling output of said visible video signal during the presence of said second part of said infrared video signal higher than said predetermined black level; and a mixing circuit for superimposing said visible video signal, output from said visible video selecting circuit, and said infrared video signal.
Claim 3
Dependent Claim 33 words
A video signal mixing device as recited in claim 1, wherein said visible video signal is output from said visible camera in synchronization with said infrared video signal output from said infrared camera.
Claim 4
Dependent Claim 60 words
A video signal mixing device as recited in claim 1, wherein said black level discriminating circuit issues a binary signal comprising a first signal indicating presence of said infrared video signal having a level higher than said predetermined black level, and a second signal indicating presence of said infrared video signal having a level lower than said predetermined black level.
Claim 5
Dependent Claim 34 words
A video signal mixing device as recited in claim 3, wherein said visible video signal selecting circuit disables output of said visible video signal during presence of said first signal of said binary signal.
Claim 6
Dependent Claim 142 words
A video signal mixing device as recited in claim 1, further comprising: an infrared video signal level adjusting circuit for receiving said infrared video signal from said infrared camera and adjusting the level of said infrared video signal to a level within a first range between the predetermined black level and a threshold level where brightness of a first image resulting from said infrared video signal is at maximum; and a visible video signal level adjusting circuit for receiving said visible video signal from said visible camera and adjusting the level of said visible video signal to a level within a second range between the predetermined black level and a level where brightness of a second image resulting from said visible video signal is at maximum, said infrared video signal level and said visible video signal level are capable of independent adjustment.
Claim 7
Dependent Claim 47 words
A video signal mixing device as recited in claim 5, further comprising: a low-pass filter, operatively connected to said infrared camera and to said black level discriminating circuit, for filtering said infrared signal from said infrared camera to eliminate electrical noises contained in said infrared video signal.
Claim 8
Dependent Claim 47 words
A video signal mixing device as recited in claim 1, further comprising: a low-pass filter, operatively connected to said infrared camera and to said black level discriminating circuit, for filtering said infrared signal from said infrared camera to eliminate electrical noises contained in said infrared video signal.
Claim 9
Dependent Claim 141 words
A video signal mixing method for superimposing a visible video signal output from a visible camera and an infrared video signal output from an infrared camera, both of the cameras viewing a common object, said video signal mixing method comprising the steps of: (a) discriminating a first part of the infrared video signal lower than a predetermined black level from a second part of the infrared video signal higher than the predetermined black level; (b) enabling output of the visible video signal during the existance of said first part of the infrared video signal lower than the predetermined black level; (c) disabling output of the visible video signal during the presence of the second part of the infrared video signal higher than the predetermined black level; and (d) superimposing the visible video signal when output enabled and the infrared video signal.
Claim 10
Dependent Claim 141 words
A video signal mixing method for superimposing a visible video signal output from a visible camera and an infrared video signal output from an infrared camera, both of the cameras viewing a common object, said video signal mixing method comprising the steps of: (a) discriminating a first part of the infrared video signal lower than a predetermined black level from a second part of the infrared video signal higher than the predetermined black level; (b) enabling output of the visible video signal during the existance of said first part of the infrared video signal lower than the predetermined black level; (c) disabling output of the visible video signal during the presence of the second part of the infrared video signal higher than the predetermined black level; and (d) superimposing the visible video signal when output enabled and the infrared video signal.
Claim 11
Dependent Claim 25 words
A method as recited in claim 8, further comprising the step of: (e) outputting the visible video signal in synchronization with the infrared video signal.
Claim 12
Dependent Claim 56 words
A method as recited in claim 8, wherein step (a) further comprises the steps of: (e) issuing a binary signal comprising a first signal indicating the infrared video signal having a level higher than the predetermined black level, and a second signal indicating the infrared video signal having a level lower than the predetermined black level.
Claim 13
Dependent Claim 35 words
A method as recited in claim 10, wherein step (c) disables output of the visible video signal when said first signal indicates the infrared video signal has a level higher than the predetermined black level.
Claim 14
Dependent Claim 108 words
A method as recited in claim 8, further comprising the steps of: (e) receiving the infrared video signal from the infrared camera; (f) adjusting the infrared video signal to a level within a first range between the predetermined black level and a level where brightness of a first image resulting from the infrared video signal is at maximum; (g) receiving the visible video signal from the visible camera; and (h) adjusting the level of the visible video signal to a level within a second range between the predetermined black level and a level where brightness of a second image resulting from said visible video signal is at maximum.
Claim 15
Dependent Claim 28 words
A method as recited in claim 12, further comprising the step of: (i) filtering out electrical noise contained in the infrared video signal received from the infrared camera.

References Cited (Backward Citations)

US4524386A Cited
US4608599A Cited
US4759072A Cited
US4843561A Cited
US4679068A Cited
US4751571A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1993-10-29 1994-04-30 1994-10-30 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1997-10-29 1998-04-30 1998-10-30 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2001-10-29 2002-04-30 2002-10-30 $7700.00 Window Closed / Lapsed

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