INSTALLATION & SETUP
Curved Screen (gain >1)
Audience Coverage
Figure 2-2. Audience Coverage with Curved Screen
Curved screens have gains larger than 1 and viewing angles much less than 180°. Most curved screens have different horizontal and vertical viewing angles. Incident light does not reflect equally in all directions. The reflected light concentrates in a conical volume or “viewing cone”. Audiences within the viewing cone see a brighter image than that from an equal area on a flat screen. Audiences outside the viewing cone see a dimmer image.
To summarize, curved screens are better suited for brightly lit rooms where the audience is situated within the viewing cone. Flat screens are best suited when a wide viewing angle is required and ambient room lighting (near the screen) is low.
Note: Screen Gain is defined in Appendix A, Glossary.
Rear Screen Installations
There are two basic types of rear screens: diffused and optical. A diffused screen has a surface which spreads the light striking it. Purely diffused screens have a gain of less than 1. The main advantage of the diffused screen is its wide viewing angle, similar to that of a flat screen for front screen projection.
Optical screens take light from the projector and redirect it to increase the light intensity at the front of the screen. This reduces it in other areas. A viewing cone, similar to that of a curved front screen installation, is created.
To summarize, optical screens are better suited for brightly lit rooms where the audience is situated within the viewing cone. Diffused screens are best suited when a wide viewing angle is required but there is low ambient room lighting.
2.4
