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Patent US3810166A successfully refreshed from Google Patents.
US3810166A
Expired / Lapsed
US
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Electronic character generating systems
Assignee: Aston Electronic Developments Ltd
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Filing: 1973-05-04
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Granted: 1974-05-07
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Expires: 1993-05-04
Abstract
Abstract An electronic system for generating characters for television display by employing selected combinations of analogue waveforms. Ramp waveforms, usually of sawtooth form, are generated at line and field periods and are used to generate in turn triangular and parabolic waveforms. A memory contains data representing the shape of individual elements of characters for each quadrant of a display area and is actuated by a digital store. The memory serves to gate selected combinations of all the waveforms, together with blanking waveforms derived from the triangular waveforms, to synthesize a video character waveform. Means is provided for producing from the video character waveform a further video waveform, defining an area to outline the characters, which acts on a conventional video signal to hold the latter at the black level so that the video character waveform can be inserted thereon.
Inventors
- 👤 L Atkin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 09:44
CPC Classifications
G; G09; G09G; G09G1/00; G09G1/06; G09G1/08; G09G1/12; G09G5/00; G09G5/22; G09G5/24
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
75 words
An electronic system for generating video signals representing characters for television display; said system comprising: a. means for producing ramp waveforms conforming with vertical and horizontal character rates, respectively; b. means for producing from each of said ramp waveforms further waveforms including at least parabolic waveforms; c. means for directly producing from selected combinations of said waveforms outputs representing character elements; and d. means for producing said video signals from said character element representing outputs.
Claim 2
Dependent Claim
75 words
An electronic system for generating video signals representing characters for television display; said system comprising: a. means for producing ramp waveforms conforming with vertical and horizontal character rates, respectively; b. means for producing from each of said ramp waveforms further waveforms including at least parabolic waveforms; c. means for directly producing from selected combinations of said waveforms outputs representing character elements; and d. means for producing said video signals from said character element representing outputs.
Claim 3
Dependent Claim
23 words
A system according to claim 1, wherein said ramp waveform producing means has separate inputs connectible to line and field sync pulse sources.
Claim 4
Dependent Claim
30 words
A system according to claim 1, wherein the ramp waveform producing means has means for controlling the frequency of the ramp waveforms to thereby control the size of the characters.
Claim 5
Dependent Claim
12 words
A system according to claim 1, wherein said waveforms include triangular waveforms.
Claim 6
Dependent Claim
12 words
A system according to claim 1, wherein said waveforms include sawtooth waveforms.
Claim 7
Dependent Claim
28 words
A system accOrding to claim 1, wherein said further waveform producing means also produces square waveforms having transistions substantially corresponding to the horizontal and vertical character centre-lines respectively.
Claim 8
Dependent Claim
40 words
A system according to claim 1, wherein said further waveform producing means comprises parabola generator means each receiving a ramp waveform and producing a parabolic waveform therefrom, the parabolic waveform generating means operating substantially independently of the ramp waveform frequency.
Claim 9
Dependent Claim
23 words
A system according to claim 1, wherein the character element producing means essentially processes the selected combinations of waveforms in a linear manner.
Claim 10
Dependent Claim
38 words
A system according to claim 1, wherein the rate of transition of the outputs of the character element producing means is substantially dependent upon and controlled by the rate of change of the selected combination of input waveforms.
Claim 11
Dependent Claim
54 words
A system according to claim 1, wherein there is further provided a memory unit serving to selectively actuate the character element producing means according to the character to be synthesised, the memory unit serving to actuate said character-element producing means to separately specify the shape of the characters in quadrants of a display area.
Claim 12
Dependent Claim
36 words
A system according to claim 10, wherein there is further provided a digital storage unit adapted to provide to the said memory unit a sequence of character codes specifying a sequence of characters to be displayed.
Claim 13
Dependent Claim
34 words
A system according to claim 11, wherein means are provided to enable the recording, editing and accessing of data in the said digital storage unit, representative of a sequence of characters to be displayed.
Claim 14
Dependent Claim
53 words
A system according to claim 11, wherein there are further provided horizontal and vertical counter units effectively clocked from the horizontal and vertical ramp waveforms respectively, the counter units having reset inputs respectively connectible to line and field synchronising pulse sources and outputs collectively specifying a character address and feeding said storage unit.
Claim 15
Dependent Claim
30 words
A system according to claim 1, wherein the character-element producing means comprises a plurality of substantially identical element generator units having inputs connected to a selected combination of the waveforms.
Claim 16
Dependent Claim
45 words
A system according to claim 10, wherein the character-element producing means comprises a plurality of substantially identical element generator units having inputs connected to a selected combination of the waveforms, the output from each element generator unit being gated by signals from said memory unit.
Claim 17
Dependent Claim
52 words
A system according to claim 1, further comprising means for selectively modifying the outputs from the said character-element producing means, said modifying means serving to generate waveforms which blank out selected parts of the outputs from the said character element producing means in relation to the quadrants of the character display areas.
Claim 18
Dependent Claim
22 words
A system according to claim 16, wherein the output from each element generator unit is gated by signals from the modifying means.
Claim 19
Dependent Claim
37 words
A system according to claim 16, wherein said modifying means comprises a horizontal modifier generator unit and a vertical modifier generator unit which generate signals which blank out selected horizontal and vertical parts of the character display.
Claim 20
Dependent Claim
62 words
A system according to claim 10, wherein there is further provided means for selectively modifying the outputs from the said character-element producing means, said modifying means being controlled by signals from the memory unit to generate waveforms which blank out selected parts of the outputs from the said character element producing means in relation to the quadrants of the character display areas.
Claim 21
Dependent Claim
59 words
A system according to claim 1, wherein a video processing means is provided having a first input for receiving a background video signal, a second input for receiving a video signal derived from said outputs of the element producinG means representing the synthesised characters and an output reproducing the background video signal having superimposed thereon a character representing component.
Claim 22
Dependent Claim
42 words
A system according to claim 1, wherein means are provided to derive from said outputs from the element producing means or from the said video signal representing the synthesised characters, a further video signal representing a definitive outline for the synthesised characters.
Claim 23
Dependent Claim
47 words
A system according to claim 20, wherein means is provided for producing a further video signal representing a definitive outline for the synthesised characters and acting as a key whereby the said video signal representing the synthesised characters may be inlaid into the said background video signal.
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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) | 1977-05-06 | 1977-11-05 | 1978-05-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-05-06 | 1981-11-05 | 1982-05-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-05-06 | 1985-11-05 | 1986-05-07 | $7700.00 | Window Closed / Lapsed |