Projection type video display
US7527680B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 21, 2005 |
| Grant date | May 5, 2009 |
| Priority date | — |
| Expiry date | Aug 3, 2027 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N9/3141
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Data of a barometric pressure that a barometric pressure sensor outputs, and data of an air volume that an air-volume sensor outputs are input into a system control circuit. The system control circuit is provided with a table storing portion. In the table storing portion, a control table is stored. The control table is formed of a plus supplied-voltage value to fan power set by a barometric pressure value and an air-volume value, and a warning instruction. In a case that the warning instruction is selected based on the barometric pressure value and the air-volume value, the system control circuit turns on a warning-use LED so as to inform a user that a filter is clogged.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.