Discharge lamp lighting device and projection type image display apparatus having the same
US7276864B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 10, 2006 |
| Grant date | Oct 2, 2007 |
| Priority date | — |
| Expiry date | Jul 10, 2026 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05B41/2882
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A computing circuit computes a target value of a current to be supplied to a discharge lamp and generates a pulse control signal for superpose a pulse current. Furthermore, the computing circuit controls a current control circuit so that a pulse current is superposed on a lamp current at a predetermined cycle and power supplied to the discharge lamp is kept constant. For that purpose, the computing circuit lowers a DC current level of the lamp current when a pulse current is superposed on the lamp current, and exercises control so that an integrated amount of power at a predetermined cycle is equalized to a predetermined integrated amount of power.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.