LED beam shaping using microlens arrays
Journal
Proceedings of SPIE - The International Society for Optical Engineering
Journal Volume
7423
Date Issued
2009
Author(s)
Abstract
Light-emitting diodes (LEDs) are very popular light sources in the market currently because of their numerous advantages such as high efficiency, long life time, wide color gamut and cheap production costs [1]. For many applications, such as illumination tasks, backlight modules and projector light sources, a homogeneous illumination of the entrance pupil is desired. Because of LED's high brightness, we can combine the homogeneous illuminance areas in the target plane together as a backlight module for LCD display to solve unreadable problems in the portable devices under the sun. Mostly, the typical light distribution of a LED shows distinct Lambertian profile which is not suitable for the applications. To achieve a better adapted beam profile, an optical system with beam shaping qualities can be used. We design an optical system consisting of refractive microlens arrays and reflection-tubes that collimates and homogenizes LED's beam [2]. The smaller angle of beams, the higher contrast ratio we will get. And the design is less than 10mm in thickness, we can use it in many ways, such as backlight module of cell phones and head-up displays (HUDs). We believe this technology has advantages and provides us a high-brightness display to read information easily.
SDGs
Type
conference paper