Lighting unit, especially for road illumination

摘要

The invention provides a lighting unit (100) comprising (a) a lighting unit cavity (130), (b) a light source unit (110), for light source unit light (111), wherein the light source unit (110) comprises a light source (1100) and a collimator (1200), and (c) a light exit window (120), configured to enclose at least part of the lighting unit cavity (130) and configured to allow transmission of at least part of the light source unit light (111) as a beam of light (101), wherein the light exit window (120) comprises an upstream face (125) and a downstream face (126), with the upstream face (125) directed to the lighting unit cavity (130); wherein the upstream face (125) comprises light outcoupling structures (140), configured to couple the light source unit light (111) via the light exit window (120) out of the lighting unit (100).

主权项

1. A lighting unit comprising:
a lighting unit cavity, a light source unit, configured to generate light source unit light, wherein the light source unit comprises a light source and a collimator, wherein the light source unit is configured to provide light source unit light in the lighting unit cavity, and a light exit window, configured to enclose at least part of the lighting unit cavity and configured to allow transmission of at least part of the light source unit light as a beam of light, wherein the light exit window comprises an upstream face and a downstream face, with the upstream face directed to the lighting unit cavity;wherein the lighting unit has a virtual first lighting unit axis in a virtual first lighting unit cross-sectional plane,wherein within the cross-sectional plane over a length at least 30% of the light exit window:
the upstream face comprises light outcoupling structures, configured to couple the light source unit light via the light exit window out of the lighting unit, wherein the light outcoupling structures comprise prismatic light outcoupling structures, the light source unit is configured to illuminate a specific subset of the light extracting structures and to generate the light source unit light at a point at the light exit window with a spread in an angle of incidence (β)≦20° of the light source unit light at said point, andwherein the lighting unit is configured to generate the beam of light downstream of the light exit window having a beam angle (γ) in the range of 90-170° within the cross-sectional plane.