NOVEL GLARE PROTECTION ELEMENT BASED ON ASYMMETRIC FRESNEL LENSES

摘要

Optical lenses usually concentrate radiation optimally if the incoming angle is orthogonal to the plane of the lens. Already small deviations from this optimal angle can reduce the concentration significanth.Especially in facade applications controlling the solar insidation this can be a considerable disadvantage. rnThe main subject of the work described here is a new optical device which is optimized for concentrating radiation from a defined non orthogonal incoming angle.In our work this was realized as a linear fresnel lens. but the functional principle can also be used with other types of lenses. The new lens properties are realized by asymmetries on the light sensitive side of the lens. The asymmetry has the aun to adapt the form of the active surface to the direction of the incoming light.rnThe novel fresnel lens can be scaled in its dimensions and in particuar it can be miniaturized.In addition the optical parameters of the new lens can be adapted very flexibly to each single application. The new lens is optimally sated for applications in which the incoming radiation is not only concentrated but also redirected. like for example in glare protection systems.