US3765018A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Digital scan converter
Assignee: Raytheon Co
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Filing: 1972-06-02
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Granted: 1973-10-09
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Expires: 1992-06-02
Abstract
Abstract There is disclosed a visual scan converter which accepts digitalized video data available from a source such as a radar receiver in any given scan pattern such as a PPI format at slow radar rates and converts the data format to make it suitable for presentation on a cathode ray tube in a standard television or other orthogonal raster at flicker free rates. Greater flexibility and economy than has heretofor been available in digital scan converters is achieved by using a random access memory. Conversion of the video data format is achieved by generating loading addresses for putting the data into memory which are representative of the functional relationship between the scan pattern at which the data was derived and that at which it is intended to be displayed. A simple counter may then be used to orthogonally address the random access memory for readout at any desired rate.
Inventors
- 👤 J Heard
- 👤 E Opittek
- 👤 H Meyers
- 👤 M Elizabeth
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 12:20
CPC Classifications
G; G01; G01S; G01S7/00; G01S7/02; G01S7/28; G01S7/285; G01S7/295; G01S7/298; H; H04; H04N; H04N7/00; H04N7/01; H04N7/0105
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
265 words
In a system including sensing means for obtaining information by producing discrete video signals as a field of view is cyclically scanned in a first predetermined pattern of successive lines at a first rate and display means for displaying said information in a second predetermined pattern of successive lines at a second rate, a digital scan converter for converting said video signals representing said information from said first pattern at said first rate to said second pattern at said second rate, comprising: a. means for converting said video signals into elements of digital data; b. buffer storage means for receiving and storing said elements of digital data at addresses corresponding to said first pattern; c. random access storage means for receiving data from said buffer storage means; d. address generating means connected to generate as a function of said first pattern at said first rate addresses to position said data in said random access storage means in positions correspondinG to said second pattern, said function representing the conversion relationship between said first and second patterns; e. means to synchronize said address generating means with said means for producing said discrete video signals and for transferring said signals into said buffer storage means and thence into said random access storage means; and f. counter means connected to provide sequential readout signals to said random access storage means to sequentially read bits of data in said storage means for presentation by said display means, said counter means also being operatively connected to synchronize a sweep generator means for said display means which receives and presents said data.
Claim 2
Dependent Claim
265 words
In a system including sensing means for obtaining information by producing discrete video signals as a field of view is cyclically scanned in a first predetermined pattern of successive lines at a first rate and display means for displaying said information in a second predetermined pattern of successive lines at a second rate, a digital scan converter for converting said video signals representing said information from said first pattern at said first rate to said second pattern at said second rate, comprising: a. means for converting said video signals into elements of digital data; b. buffer storage means for receiving and storing said elements of digital data at addresses corresponding to said first pattern; c. random access storage means for receiving data from said buffer storage means; d. address generating means connected to generate as a function of said first pattern at said first rate addresses to position said data in said random access storage means in positions correspondinG to said second pattern, said function representing the conversion relationship between said first and second patterns; e. means to synchronize said address generating means with said means for producing said discrete video signals and for transferring said signals into said buffer storage means and thence into said random access storage means; and f. counter means connected to provide sequential readout signals to said random access storage means to sequentially read bits of data in said storage means for presentation by said display means, said counter means also being operatively connected to synchronize a sweep generator means for said display means which receives and presents said data.
Claim 3
Dependent Claim
61 words
A system as in claim 1 wherein said address generating means is connected to generate at said first rate addresses as a function of the said first pattern which is a radar-type sector plan position indicator scan and position said data in said random access storage means in positions corresponding to a second pattern which is a horizontal standard television raster.
Claim 4
Dependent Claim
63 words
A system as in claim 1 wherein said address generating means is connected to generate at said first rate addresses as a function of a first pattern which is a radar-type B-scan having azimuth and range as orthogonal coordinates and position said data in said random access storage means in positions corresponding to a second pattern which is a horizontal standard television raster.
Claim 5
Dependent Claim
19 words
A system as in claim 1 wherein said random access storage means comprises a random access metal-oxide semiconductor memory.
Claim 6
Dependent Claim
127 words
A system as in claim 2 wherein said address generating means comprises: a. a range ramp counter for providing a digital signal representing the range of a given element of video data; b. digital read-only memory means for storing values of the trigonometric sine and cosine of azimuth angles; c. a pair of digital multipliers, one of said multipliers being connected to multiply the output of said range ramp counter by the sine of said azimuth angle to generate the X component of the address for said random access memory and the other of said multipliers being connected to multiply the output of said range ramp counter by the cosine of said azimuth angle to generate the Y component of said address for said random access memory.
Claim 7
Dependent Claim
60 words
A system as in claim 3 wherein first circuit means are provided to utilize digital values of said azimuth angle as the X component of the address in said random access memory and second circuit means are provided to utilize the output of said digital range ramp counter as the Y component of said address for said random access memory.
Claim 8
Dependent Claim
59 words
Apparatus as in claim 5 wherein said range ramp counter is triggered by the output of an AND gate which controls the transfer of video information from said input buffer to said random access memory, one input to said AND gate being a load gate signal and the other input to said AND gate being a load clock signal.
Claim 9
Dependent Claim
152 words
In a digital scan converter for converting video data available of a first scan pattern to video data for display in a second scan pattern, the improvement comprising: a. random access memory means for receiving said available video data in digitalized form; b. address generating means connected to generate as a function of said first scan pattern addresses to position said video data in said random access storage means in positions corresponding to the sequential read out order of said second scan pattern, said function representing the conversion relationship between said first and second patterns; c. means to read said digitalized video data into said random access memory means synchronously with the generation of said addresses and at the positions designated by said addresses; and d. counter means connected to provide sequential readout signals to said random access memory means to sequentially read said video data stored at said addresses for display.
Claim 10
Dependent Claim
152 words
In a digital scan converter for converting video data available of a first scan pattern to video data for display in a second scan pattern, the improvement comprising: a. random access memory means for receiving said available video data in digitalized form; b. address generating means connected to generate as a function of said first scan pattern addresses to position said video data in said random access storage means in positions corresponding to the sequential read out order of said second scan pattern, said function representing the conversion relationship between said first and second patterns; c. means to read said digitalized video data into said random access memory means synchronously with the generation of said addresses and at the positions designated by said addresses; and d. counter means connected to provide sequential readout signals to said random access memory means to sequentially read said video data stored at said addresses for display.
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) | 1976-10-08 | 1977-04-09 | 1977-10-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-10-08 | 1981-04-09 | 1981-10-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-10-08 | 1985-04-09 | 1985-10-09 | $7700.00 | Window Closed / Lapsed |