Apparatus and method for driving liquid crystal
US5771030A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 30, 1995 |
| Grant date | Jun 23, 1998 |
| Priority date | — |
| Expiry date | Jan 30, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG09G2320/02
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
To drive a liquid crystal panel without producing flickering or noise on a screen, an adder circuit 26 adds the noise component of the analog signal detected in a filter 24 to a reference voltage from a power supply 16, and a phase adjustment circuit 28 adjusts the phase of the reference voltage to which the noise component was added. A circuit 12 holds the analog signal and outputs it to comparators 14.sub.1 to 14.sub.n. The reference voltage from the circuit 28 is divided in resistors 18.sub.1 to 18.sub.n+1 and output to comparators 14.sub.1 to 14.sub.n as threshold voltages TV.sub.1 to TV.sub.n. The comparator 14 compares the input analog signal to the voltage TV, and outputs a predetermined signal to an encoder 20 if the analog signal is greater than the voltage TV. The encoder 20 converts the signal from the comparator 14 to a digital signal and applies it to the electrode of a liquid crystal panel.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.