| 摘要 |
<p>A diffractive light outcoupling unit (404) for forming a part of a directive light outcoupling system of a lighting device comprising a plurality of diffractive outcoupling units, wherein said diffractive light outcoupling unit comprises a carrier element (401) for accommodating a diffractive surface relief pattern (406), and a diffractive surface relief pattern comprising a plurality of consecutive diffractive surface relief forms defined on a surface area of the carrier element, wherein the form period is preferably about 10 microns or less, arranged to couple light incident on said diffractive surface relief pattern outside the carrier element via interaction involving at least two surface relief forms of said plurality of surface relief forms of said diffractive surface relief pattern so as to enhance the directivity of the coupled light. In addition, a diffractive light outcoupling system including a plurality of diffractive light outcoupling units, and a lightguide including the outcoupling system, are presented.</p> |
