Front projector system with separated base unit and projection head
Publication Date: 2004-Feb-09
The IP.com Prior Art Database
Front projector system with separated base unit and projection head.
The invention relates to a front projection system for displaying image information comprising a light source for generating a light beam, a display panel for modulating the generated light beam with the image information and a projection lens for projection of the modulated light beam on a screen.
This projection system can be used as an automotive display i.e. as a display for use in a car. Presently, the first automotive vehicles have appeared on the market containing a front projection system for infotainment to the driver or passengers. Many new applications using projection display solutions in the car are under consideration by car manufacturers.
Presently front projection systems have the best picture performance for car display applications. Front projection systems showed a high contrast image, a large display area for data and video application using a small, dimmed, DLP front projector, and a holographic front projection screen. This concept features a high contrast at high ambient light condition such as sunlight but also allows for curved projection surfaces in the shape of the car dashboard.
Within this known front projection concept, the front projection system is located close to the ceiling of the car, e.g. between the windscreen and the rear mirror. For this reason the front projection system needs to be extremely small, for example the size of a cigarette box, because of the relatively small space behind the wind screen and the rear mirror compared to the size of conventional front projection systems.
The objective of this invention is to enable a front projection solution having an extremely small projection unit that is visual from the viewer's area in the projection space. The invention proposes to split the projection system in 3 units:
1. An ultra compact projection head containing only the display panel(s), the projection lens, some illumination optics and miniaturised display drive electronics.
2. A base unit containing the light source, light collection optics, power supply and the small
3. A glass fibre for transporting a first light beam from the base unit to the projection head
and for simultaneously transporting a second light beam from the base unit to the projection
head containing the image information to be projected. This solution offers the smallest projection head and enables concealment of the other required parts of the projection system at a convenient, invisible, location, and a minimum of interconnections between the two units.
Fig. 1 shows an example of a projection system for a car. The projection system 1 comprises the base...