Auto-focusing projection system
US9420245B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 26, 2012 |
| Grant date | Aug 16, 2016 |
| Priority date | — |
| Expiry date | Apr 8, 2033 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03B21/142
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An auto-focusing projection system includes a projection module, an infrared monitoring module (300), an infrared source (400) provided on the projection module, and a focusing device for driving the first lens group (201) moving forward and backward. An IR light spot emitted from the infrared source falls within the monitoring scope of the infrared monitoring module, preferably inside the projected picture of the projection module or on the edge thereof, and after reflected back, it also can travel through the first lens group, and the splitting element in turn, and then be transmitted to the infrared monitoring module. Analyzing the IR light spot picture emitted from the infrared source which is collected by the infrared monitoring module, a control signal can be sent to a focusing motor to adjust the first lens group to an appropriate position, so as to realize auto-focusing.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.