US3812485A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Visual display device
Assignee: Fujitsu Services Ltd
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Filing: 1972-05-08
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Granted: 1974-05-21
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Expires: 1992-05-08
Abstract
Abstract A visual display device is described for drawing lines on the face of a cathode ray tube. Information describing the lines to be drawn is held in a store and is presented in the form of positional information describing one end (the initial end) of a line together with values representing the displacement from the initial end of the terminal end of the line. By relative shifting operations on this information a standardised line drawing speed is achieved by the repeated cyclic addition of the shifted displacement values into a register holding the positional and displacement information. Other relative shifting of positional and displacement information permits effective speeding up of ''''drawing'''' any part of a line that disappears off the field of view of the cathode ray tube and the shifting of both position and displacement values enables the scale of the drawn display to be altered.
Inventors
- 👤 D Moreton
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 14:07
CPC Classifications
G; G09; G09G; G09G1/00; G09G1/06; G09G1/08; G09G1/10
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
298 words
Visual display apparatus for controlling the effective drawing speed of a line having initial and terminal ends respectively, the line being drawn by deflection of an electron beam over a cathode ray tube display face of predetermined area, including for each of two co-ordinate axes respectively a multidenominational accumulating position regIster, the position registers being arranged respectively initially to store binary coded digital beam deflection values together representative of the position of the initial end of the line to be drawn; a multidenominational accumulator connected as an extension to that end of the position register having least denominational significance the connection permitting overflow digits from the accumulator to be accumulated in the position register; and a multidenominational displacement shift register; means for entering into the displacement registers binary coded digital displacement values respectively representing relative to the position of the initial end of the line the position of the terminal end of the line, all the binary-coded digital values being expressed respectively in terms of minimum beam displacement increments, the significance of the denominations of each displacement register corresponding respectively to those of the combined position register and accumulator of the same axis; indicating means arranged to produce separately for each axis a first control signal if like digital representations occur concurrently in all those denominations of the displacement register having significance corresponding to the denominations of the position register; means for shifting the digital representations in the displacement register towards the least significant denomination in the absence of one at least of said first control signals and for arresting and shifting when the first control signals are produced for both axes; means for repeatedly adding the shifted representations into the accumulators; and means for terminating the addition when the terminal end of the line has been drawn.
Claim 2
Dependent Claim
298 words
Visual display apparatus for controlling the effective drawing speed of a line having initial and terminal ends respectively, the line being drawn by deflection of an electron beam over a cathode ray tube display face of predetermined area, including for each of two co-ordinate axes respectively a multidenominational accumulating position regIster, the position registers being arranged respectively initially to store binary coded digital beam deflection values together representative of the position of the initial end of the line to be drawn; a multidenominational accumulator connected as an extension to that end of the position register having least denominational significance the connection permitting overflow digits from the accumulator to be accumulated in the position register; and a multidenominational displacement shift register; means for entering into the displacement registers binary coded digital displacement values respectively representing relative to the position of the initial end of the line the position of the terminal end of the line, all the binary-coded digital values being expressed respectively in terms of minimum beam displacement increments, the significance of the denominations of each displacement register corresponding respectively to those of the combined position register and accumulator of the same axis; indicating means arranged to produce separately for each axis a first control signal if like digital representations occur concurrently in all those denominations of the displacement register having significance corresponding to the denominations of the position register; means for shifting the digital representations in the displacement register towards the least significant denomination in the absence of one at least of said first control signals and for arresting and shifting when the first control signals are produced for both axes; means for repeatedly adding the shifted representations into the accumulators; and means for terminating the addition when the terminal end of the line has been drawn.
Claim 3
Dependent Claim
91 words
Apparatus as claimed in claim 1 in which the shifting means includes control means and the terminating means is connected to said control means and includes a pointer register and a counter, the contents of the pointer register being shifted in synchronism with the relative shifting applied to the displacement register and being added into the counter in synchronism with the adding of the contents of the displacement register into the position register, the control means responding to the registration of a predetermined value in said counter to terminate the addition.
Claim 4
Dependent Claim
162 words
Apparatus as claimed in claim 2 including an information store arranged to store for both axes respectively in respect of each line to be drawn initial position values representing the initial end and the displacement values representing the terminal end, the values being expressed in relation to a notional display area larger than said predetermined area; means for entering the initial position values into the respective position registers; indicating means for each axis arranged to examine predetermined denominations of higher denominational significance of a position value to produce a second control signal if that part of a line currently to be drawn falls within said predetermined area, the control means being responsive to the absence of second control signals to modify the degree of relative shifting applied values entered into the displacement registers to skip over those parts of the line outside said predetermined area at a higher speed than that effective drawing speed of a line portion within the predetermined area.
Claim 5
Dependent Claim
86 words
Apparatus as claimed in claim 3 including a further store containing values representative of the position of the required display area relative to the virtual total display expressible by values within the information store and in which the means for entering the values from the information store into the position registers is connected to said further store and includes means for arithmetically modifying the position values from the information store by values from said further store to represent positions with respect to the required display area.
Claim 6
Dependent Claim
36 words
Apparatus as claimed in claim 4 in which the entering means further includes means for applying a predetermined Shift to values before entry into the position and displacement registers to modify the scale of displayed lines.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-05-20 | 1977-11-19 | 1978-05-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-05-20 | 1981-11-19 | 1982-05-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-05-20 | 1985-11-19 | 1986-05-21 | $7700.00 | Window Closed / Lapsed |