Portable projection display apparatus
US5738429A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 5, 1995 |
| Grant date | Apr 14, 1998 |
| Priority date | — |
| Expiry date | Jun 5, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02F1/133623
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
The present projection display apparatus includes an illumination source, an LCD panel including a polarizing plate, a light projecting and receiving combinational lens, a screen, a light pen, a detection-use polarizing plate, a CCD, and a control circuit for controlling an operation of the LCD panel upon receiving a signal from the CCD. The combinational lens throws light of a display image from the LCD panel to project the light on the screen. Meanwhile, the lens receives light from the display image and luminescent spot light from the pen to focus them on the LCD panel and then reflect the same to make them incident on the CCD via the detection-use polarizing plate. The detection-use polarizing plate does not transmit the light of the display image.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.