| 摘要 |
The invention relates to a lighting device comprising a light source ( 1 ) that emits incoherent light with a total radiation power P and has a radiation-emitting area (S) divided into a plurality of subareas (S<SUB>i</SUB>), wherein assigned to each subarea (S<SUB>i</SUB>) is a light ray ( 2 ) having a radiation power P<SUB>i </SUB>and the sum of the radiation powers P<SUB>i </SUB>is equal to the total radiation power P, and disposed after said light source ( 1 ) is an optical element ( 4 ) having a decoupling surface ( 5 ) and a total reflection angle (theta<SUB>c</SUB>) assigned to said decoupling surface ( 5 ), said decoupling surface ( 5 ) being shaped so that at least for a portion of said light rays ( 2 ) the angle (alpha) of incidence on said decoupling surface ( 5 ) is smaller than the total reflection angle (theta<SUB>c</SUB>), and the radiation power of said light rays collectively is greater than a predetermined fraction, equal to at least 50%, of the total radiation power P.
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