US4677481A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Dual display monitor
Assignee: Tektronix Inc
•
Filing: 1986-03-17
•
Granted: 1987-06-30
•
Expires: 2006-03-17
Abstract
Abstract A waveform monitor for television has dual video channels displayed simultaneously side-by-side. The two channels are synchronized with each other or with an external sync signal and are input to a multiplexer prior to the display. A microprocessor controls the switching of the multiplexer according to the selection made by an operator. The first channel is displayed during the first half of the horizontal display sweep, and the second channel is displayed during the second half, the horizontal sweep encompassing two horizontal lines of video.
Inventors
- 👤 Dan H. Nicholas
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 15:04
CPC Classifications
H; H04; H04N; H04N5/00; H04N5/44; H04N5/445; H04N5/45
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
70 words
A dual waveform display device comprising: means for switching between two channels of synchronized video information in the form of video waveforms having as inputs the two channels of synchronized video information and as an output one of the two channels of synchronized video information; and means for controlling the switching means so that the two channels are displayed horizontally side-by-side during a single horizontal sweep across the display device.
Claim 2
Dependent Claim
70 words
A dual waveform display device comprising: means for switching between two channels of synchronized video information in the form of video waveforms having as inputs the two channels of synchronized video information and as an output one of the two channels of synchronized video information; and means for controlling the switching means so that the two channels are displayed horizontally side-by-side during a single horizontal sweep across the display device.
Claim 3
Dependent Claim
72 words
The dual display device as recited in claim 1 further comprising: sync selection means for switching between the output of the channel switching means and an external video signal under control of the controlling means; and means for extracting horizontal sync pulses from the output of the sync selection means for input to the controlling means for use by the controlling means in providing the timing for controlling the channel switching means.
Claim 4
Dependent Claim
101 words
The dual display device as recited in claim 2 wherein the controlling means comprises: a microprocessor having as inputs a selected display mode and the horizontal sync pulses from the extracting means, and outputting for each horizontal sync pulse a serial data word to be executed upon the receipt of the next horizontal sync pulse, the serial data word being a function of the selected display mode; and a latch into which the serial data word is loaded between horizontal sync pulses, and which transfers the serial data word to the latch output upon receipt of the next horizontal sync pulse.
Claim 5
Dependent Claim
51 words
The dual display device as recited in claim 3 wherein the channel switching means comprises a modulator circuit configured as a multiplexer so that the output of the multiplexer is determined by the serial data word at the output of the latch, the input being the two channels of video information.
References Cited (Backward Citations)
US3074014A
Cited
US3525087A
Cited
US3818474A
Cited
US3872461A
Cited
US3876936A
Cited
US4222048A
Cited
US4577188A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-06-29 | 1990-12-29 | 1991-06-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-06-29 | 1994-12-29 | 1995-06-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-06-29 | 1998-12-29 | 1999-06-30 | $7700.00 | Window Closed / Lapsed |