Portable xenon arc light coagulator.

The Log-2 portable xenon arc light coagulator (Fig. i) was developed (O'Malley, 1971) in an attempt to simplify the operative procedure and to make this form of therapy more widely available. The key to the small size of this instrument is a parabolic reflector built into the lamp (Fig. 2). The reflector redirects the radiation so efficiently that a I50 watt lamp performs the same function as the 2,000 watt lamp in Meyer-Schwickerath's light coagulator. However, the reflector produces important differences in the configuration of the light beam delivered to the patient's eye. This instrument also differs from the Zeiss coagulator in several optical, electronic, and mechanical features. We examine here the