| 摘要 |
A display case luminaire (30) comprises a linear housing, array (32) of LED light sources, and lens (33), wherein the lens provides a substantially uniform spread of light across a target plane even if the luminaire is located to emit light generally at an acute angle to the plane. The lens (33) is a Fresnel lens and has non-uniform optical characteristics in cross-section, with at least two different focal lengths. The linear housing comprises a visor (36) and a reflective surface (35) externally of the lens and a reflective surface (35) between the lens and the light source. A display case luminaire as claimed in any preceding claim, wherein the housing is configured for mounting back-to-back with another similar luminaire to provide a field of emission in the range of 150 degrees to 180 degrees. The housing is generally quadrant-shaped in cross-section, and the lens may be tilted with respect to the light source. |
