Optical Design of an UV-LED Edge-Lighting Glass Model

Abstract

Within the framework of a partner project sponsored by the Federal Ministry we are developing a self-disinfecting operation interface with a glass panel and several integrated UV-LEDs. The concept of self-disinfection is based on the exploitation of the photocatalytical effect induced by a TiO2-coating on the glass surface under UV(A).

The main goal and challenge of the optical design is to generate an efficient and preferably homogeneous UV field on the coated side while keeping the LED light sources hiding behind. Therefore we referenced from common backlighting systems and modified it to meet the concrete requirements. An appropriate optical simulation was conducted with a computer program LightTools® as a primary study. Several patterns for light redirecting, particularly 3D-sphere texture, 3Drectangular texture and 2D-serigraph were investigated, compared and evaluated. Finally one design of the pattern was chosen which can fulfill all the predefined boundary conditions while reducing the costs simultaneously.