US3838310A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Auto centering for multiple tube television color cameras
Assignee: Ampex Corp
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Filing: 1973-03-23
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Granted: 1974-09-24
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Expires: 1993-03-23
Abstract
Abstract An automatic centering system is provided for multiple tube color cameras utilizing a plurality of channels of electronics, wherein at least one channel generates a signal which is the first derivative of either the red, green or blue color video signal introduced into the channels from a video color camera. In one embodiment of the centering circuit, the red and blue color signals are introduced to respective channels of the system, and each are multiplied by the first derivative of the green color signal. The resulting pair of centering signals are integrated to provide error signals which represent the amount and direction of any mis-centering between the green component image and the red and/or blue component images respectively. In another embodiment of the centering circuits, the first derivatives of the red and blue signals are each multiplied by the green color signal. The resulting pair of centering signals are integrated to provide error signals which represent the amount and direction of any mis-centering between the green and red and/or blue component images. Either of the embodiments may be used to correct vertical and/or horizontal mis-centering. In either embodiment, any miscentering in either the vertical or horizontal direction is used to control up/down counter means, whereby a corresponding analog correction signal is supplied, via digital-to-analog means, to the scanning apparatus of the respective camera tubes.
Inventors
- 👤 G Varian
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 23:22
CPC Classifications
H; H04; H04N; H04N23/00; H04N23/10; H04N23/13; H04N23/15
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
175 words
An automatic centering system for correcting any miscentering between the color component images of a multiple tube color camera, wherein the camera generates selected color signals within respective color channels in response to the number and properties of the tubes, and corrections are applied via the tube scan apparatus, comprising; first means for continuously generating a first derivative from at least one of the color signals of a respective color channel; multiplier means for receiving the first derivative and at least one other color signal from another color channel and for continuously multiplying the first derivative of one color channel by the color channel of a different color channel to provide continuous error signals indicative of any miscentering between the color signals of the different color channels; comparator means operatively coupled to the multiplier means for cintinuously comparing the error signals to a selected threshold reference to generate correction signals commensurate with the error signals, wherein the correction signals are applied to the tube scan apparatus to correct any mis-centering between the color component images.
Claim 2
Dependent Claim
175 words
An automatic centering system for correcting any miscentering between the color component images of a multiple tube color camera, wherein the camera generates selected color signals within respective color channels in response to the number and properties of the tubes, and corrections are applied via the tube scan apparatus, comprising; first means for continuously generating a first derivative from at least one of the color signals of a respective color channel; multiplier means for receiving the first derivative and at least one other color signal from another color channel and for continuously multiplying the first derivative of one color channel by the color channel of a different color channel to provide continuous error signals indicative of any miscentering between the color signals of the different color channels; comparator means operatively coupled to the multiplier means for cintinuously comparing the error signals to a selected threshold reference to generate correction signals commensurate with the error signals, wherein the correction signals are applied to the tube scan apparatus to correct any mis-centering between the color component images.
Claim 3
Dependent Claim
41 words
The centering system of claim 1 further including gateable integrator means operatively coupled to the multiplier means to provide selected integration and thus an averaging of the error signals for subsequent comparison with the selected threshold reference via the comparator means.
Claim 4
Dependent Claim
35 words
The centering system of claim 2 further including gating means integral with the gateable integrator means to apply the integrated error signals to the comparator means for comparison with the selected DC voltage threshold reference.
Claim 5
Dependent Claim
36 words
The centering system of claim 3 further including chopper means coupled to selected color signals prior to the multiplier means and to the first means to establish a zero DC reference level for respective color signals.
Claim 6
Dependent Claim
43 words
The centering system of claim 3 further including voltage divider means for providing the selected threshold reference coupled to the gating means, and further coupled to the comparator means to provide upper and lower threshold levels with respect to the selected threshold reference.
Claim 7
Dependent Claim
31 words
The centering system of claim 4 further including timing means operatively coupled to the comparator means, to the gateable integrator means and to the chopper means to sequentially gate the system.
Claim 8
Dependent Claim
43 words
The centering system of claim 5 further including up/down counter means operatively coupled to the comparator means and responsive to variations of the error signals relative to the upper and lower threshold levels to generate a digital word indicative of the error signals.
Claim 9
Dependent Claim
41 words
THe centering system of claim 7 further including D/A converter means coupled to the counter means for generating the correction signals in the form of an analog voltage which is proportional to the digital word and thus to the error signals.
Claim 10
Dependent Claim
37 words
The centering system of claim 8 further including filter means associated with each color signal of respective color channels for removing low frequency components which are not related to video picture transitions and to eliminate sampling transients.
Claim 11
Dependent Claim
41 words
The centering system of claim 4 further including sample/hold means for receiving each of the color signals, and responsive to the chopper means to selectively sample color signal information down the picture; said chopper means being gated at a preselected rate.
Claim 12
Dependent Claim
65 words
The centering system of claim 4 wherein the color camera is centered in both the horizontal and vertical directions; wherein the first means, the multiplier means, the comparator means, the gating means, the gateable integrator means, and the chopper means are disposed to provide both a horizontal and vertical centering circuit, wherein associated horizontal and vertical correction signals are introduced to respective tube scan apparatus.
Claim 13
Dependent Claim
81 words
The centering system of claim 11 further including sample/hold means disposed to receive the color signals in the vertical circuit, said chopper means being responsive to a selected input signal and coupled to the sample/hold means to sample the associated color signal and establish the zero DC reference level; and wherein the chopper means of the horizontal circuit is coupled to a color signal prior to the first means for obtaining the derivative thereof to establish the zero DC reference level.
Claim 14
Dependent Claim
134 words
The centering system of claim 12 wherein the vertical and horizontal circuits include RGB color signals introduced to respective channels, the system further including, bandpass filter means and highpass filter means coupled to the sample/hold means in the vertical circuit and to the chopper means in the horizontal circuit, respectively; said means for obtaining a first derivative being disposed in two channels of the vertical circuit, the vertical multipliers means being disposed to multiply each of the two derivatives by the remaining color signal to define a pair of vertical error signals; said means for obtaining a first derivative being disposed in one channel of the horizontal circuit, the horizontal multiplier means being disposed to multiply the first derivative by each of the remaining color signals to define a pair of horizontal error signals.
Claim 15
Dependent Claim
96 words
The centering system of claim 13 further including; a first amplifier stage coupled to the multiplier means of the vertical and horizontal circuits, the gateable integrator means being coupled to respective first amplifier stages; coupling capacitor means coupled to the integrator means and thence to the gating means; said comparator means being coupled to respective coupling capacitor means via associated gating means; up/down counter means coupled to respective comparator means and adapted to count up or down in response thereto, wherein said counter means generates respective digital words indicative of the vertical and horizontal corrections signals.
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) | 1977-09-23 | 1978-03-25 | 1978-09-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-09-23 | 1982-03-25 | 1982-09-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-09-23 | 1986-03-25 | 1986-09-24 | $7700.00 | Window Closed / Lapsed |