Selection of Rear Projection Screens for Learning Carrels,
Abstract
The selection of a rear projection screen for a learning carrel should take into account the viewing angle involved. In some carrels, the screens are utilized primarily to present information. In such cases, the viewer can be seated directly in front of the screen, i.e., on the normal axis. In cases where the screen will be viewed only from a very restricted range, a highly directional screen may be employed. Since such a screen disperses light only to a small area (restricted exit pupil), the light is highly concentrated. A relatively small output is required. This condition is usually favorable in terms of operational economics, reliability, heat generation, noise level, and maintainability. In a very real sense, the level of illumination is controlled by the position of the viewer; he moves to obtain the best image. In other carrels, the learning situation requires that the viewer be mobile, that he move from place to place to perform tasks or complete activities. To facilitate the matching of a requirement with a screen, 21 commercially available screens were evaluated using a goniophotometer. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 1970
- Accession Number
- AD0717713
Entities
People
- Edgar A. Smith
Organizations
- Brooks Air Force Base