Resonant mode active matrix TFEL display excitation driver with sinusoidal low power illumination input
US5793342A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 3, 1995 |
| Grant date | Aug 11, 1998 |
| Priority date | — |
| Expiry date | Oct 3, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG09G2330/02
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Energizing an active matrix electroluminescent device with a generally sinusoidal illumination waveform causes the electroluminescent layer to emit light. A sinusoidal waveform minimizes the peak currents reducing the likelihood of burnouts and decreases the imposed voltages on the data lines increasing the likelihood that the high voltage transistors will function as intended. Preferably, the sinusoidal waveform is generated by using a single 12 volt power source which reduces the expense, weight and bulk of the electroluminescent device. The 12 volt power source may be used to operate an operational amplifier that receives a small sinusoidal input signal and produces a low voltage generally sinusoidal waveform that is amplified by a step-up transformer for energizing the transparent electrode layer of the device so as to cause the electroluminescent layer to emit light. Furthermore, the use of a generally low voltage operational amplifier permits the routing of a 12 volt power signal from a remote power source, such as a battery, to a head-mounted active matrix electroluminescent device, reducing safety concerns routing of high voltage signals near the body of the user.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.