NCJ Number
74896
Journal
Security Management Volume: 25 Issue: 1 Dated: (January 1981) Pages: 45,48,50-54,57-63
Date Published
1981
Length
14 pages
Annotation
Technical information on the operations and installation of closed-circuit television systems for security observations is provided.
Abstract
Such systems can offer additional security without increases in the number of security personnel and can record activities at a location for subsequent review or for long-term records. They can document the committing of crimes and aid in the identification of offenders. The typical one-camera layout is described; and environmental factors, such as lighting, which influence the location of equipment are identified. Lens selection receives special attention since this is the most difficult part of designing a system. The relationships among the lens and the field of vision, the magnifying power, and the focal length are discussed; and fixed focal length lenses, zoom lenses, and automated lenses are described. A number of specialty lenses are also considered: split-image, right-angle, pin-hole, and C-mount lenses. Furthermore, information on the various types of vidicon tubes manufactured for security applications is presented. The various means of signal transmission discussed include the coaxial cable the most common dedicated wires, and wireless systems which use microwaves or lasers. Also, monitors, accessories, and new technology are described as are installation and mounting and some common applications of television systems. Photographs, graphs and tables, diagrams, and a glossary are provided. A reference list is not included.