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公开(公告)号：DE3580759D1
公开(公告)日：1991-01-10
申请号：DE3580759
申请日：1985-09-03
Applicant: IBM
Inventor： MORRISH ANDREW JOHN , WELLS JOHN HENRY
Abstract: An interlaced raster-scanned color cathode ray tube display in which flicker is reduced by temporally off-setting one of the colors (preferably red) so that normally even-field data for that color is displayed in the odd field and normally odd-field data for that color is displayed in the even field. The temporal shift can be either before or during storage of the bit patterns or during or after reading of the bit patterns. The resulting positional shift of one scan line of the temporally shifted color is compensated for by using the static and/or dynamic convergence circuitry.
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公开(公告)号：GB2269030A
公开(公告)日：1994-01-26
申请号：GB9215896
申请日：1992-07-25
Applicant: IBM
Inventor： GIBBS TERENCE KEITH , LUCK GRAHAM , EAGLE DAVID JOHN , MORRISH ANDREW JOHN , FINDLAY VALERIE MCCLAREN
Abstract: An elapsed time recording device includes a counter (130) for incrementally advancing a count value from an initial value towards and beyond a threshold in response to successive clock pulses of a clock signal. Control logic (140) enables the counter (130) to incrementally advance the count value in response to a first input (pin 3) and a second input (pin 1) being at or near a first voltage level, and holds the count value in response to the first input (pin 3) being at or near a second voltage level and the second input (pin 1) being at or near the first voltage level. Setting logic (210) sets the count value to a value beyond the threshold in response to the first input (pin 3) and the second input (pin 1) being at or near the second voltage level when the count value is between the initial value and the threshold.
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公开(公告)号：GB2262692A
公开(公告)日：1993-06-23
申请号：GB9126997
申请日：1991-12-19
Applicant: IBM
Inventor： MORRISH ANDREW JOHN , EAGLE DAVID JOHN
Abstract: Cathode ray tube display apparatus comprises a cathode ray tube display screen (10) for displaying successive frames of a non-interlaced video image in response to excitation by at least one raster-scanned electron beam. A line timebase circuit (40) sequentially addresses the or each electron beam to successive pixels on the screen in a line of a raster in response to a line timebase sync signal. A frame timebase (50) circuit sequentially addresses the or each electron beam to successive lines of the raster in response to a frame timebase sync signal. The frame timebase circuit (50) comprises means for offseting successive frames of the video image in a direction transverse of the lines of the raster by a distance less than the spacing of adjacent lines of the raster. Gaps between adjacent pixels on successive lines of the raster are made invisible to the viewer because the persistence of a viewers eye effectively integrates the image content of successive frames. Also, because the successive frames have the same image content, there is no low frequency component in the image spectrum below the frame timebase frequency. Therefore, the displayed image is free from objectionable flicker.
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公开(公告)号：GB2232044A
公开(公告)日：1990-11-28
申请号：GB8911656
申请日：1989-05-20
Applicant: IBM
Abstract: A CRT heater circuit for a CRT display is described, the circuit comprising control means (4) for dynamically varying a voltage (Vh) across the cathode heater in response to variations in the beam current density (I) within the CRT. In this way the optimum voltage across the heater coils is maintained, thus preventing "cathode stripping" at times of peak beam currents, and optimising the CRT's working lifetime.
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Patent Agency Ranking
公开(公告)号：DE69303170D1
公开(公告)日：1996-07-18
申请号：DE69303170
申请日：1993-08-18
Applicant: IBM
Inventor： MORRISH ANDREW JOHN
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公开(公告)号：DE69015438D1
公开(公告)日：1995-02-09
申请号：DE69015438
申请日：1990-05-14
Applicant: IBM
Abstract: A CRT heater circuit for a CRT display is described, the circuit comprising control means (4) for dynamically varying a voltage (Vh) across the cathode heater in response to variations in the beam current density (I) within the CRT. In this way the optimum voltage across the heater coils is maintained, thus preventing "cathode stripping" at times of peak beam currents, and optimising the CRT's working lifetime.
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公开(公告)号：GB2269080A
公开(公告)日：1994-01-26
申请号：GB9215857
申请日：1992-07-25
Applicant: IBM
Inventor： MORRISH ANDREW JOHN
Abstract: The deflection comprises a ramp generator 210 for producing a current ramp signal synchronised to a raster synchronisation signal. A ramp regulator 230 is connected to the generator 210 for varying the amplitude of the scan signal as a function of the difference between a reference input and a feedback signal. A feedback circuit 220 is connected to the generator 210 and to the regulator 230 for generating the feedback signal as a function of the amplitude and frequency of the line scan signal. A multiplier 250 is connected to the regulator and for varying the reference input is a function of an integer multiple of the frequency of the raster synchronisation signal. Any scan signal frequency component in the feedback signal is cancelled at the input to the regulator by introducing, via the multiplier 250, a scan signal frequency component to the reference input. Because the displayed picture size is thus made independent of scan signal frequency, the deflection apparatus can maintain a constant picture size despite variations in scanning signal frequency without the bandwidth limitations of the prior art.
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