Precision approach path indicator

摘要

A Precision Approach Path Indicator (PAPI) unit comprises first and second light sources (366,367) and a projection lens assembly (40). Light emitted by the first and second light sources (366,367) is collected by first and second solid waveguides (37) respectively and is guided by said waveguides (37) to an intermediate plane. The intermediate plane is located in the focal plane of the projection lens assembly (40).