Tubular light for use in wet environments or underwater has cylindrical housing with ribs which are parallel to its axis and are arranged to form Fresnel pattern, so that light is emitted over predetermined angle

摘要

Tubular light for use in wet environments or underwater has a cylindrical housing (R) with ribs (F) which are parallel to its axis. These are arranged to form a Fresnel pattern, so that light is only emitted over a predetermined angle.