Method and circuitry for producing dynamic illumination of discharge lamp
US5453668A · kind A · utility
Inventor
Key dates
| Filing date | Mar 23, 1994 |
| Grant date | Sep 26, 1995 |
| Priority date | — |
| Expiry date | Mar 23, 2014 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05B41/2928
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A sweeping signal generator generates sequences of logic-level pulses of variable pulse-width. The logic-level pulses are amplified and applied to the electrodes of a discharge lamp. The illumination region of the discharge lamp is dynamically varied in size by dynamically varying the widths of the pulses, thereby producing sweeping effects and other display effects. In the preferred embodiment the sweeping signal generator comprises a microprocessor, a counter and a tri-state buffer. The microprocessor periodically loads the counter with an initial count value to initiate a pulse at the output of the tri-state buffer. The value loaded into the counter controls the duration of the pulse. Pulses are then amplified using a circuit which comprises a switching transistor, a power source, and a step-up transformer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.