Abstract
The efficiency of white light LED has been improved progressively in recently years. Many high lumen white light LED have been announced, it can be competitive to convention light source. These works show special illumination applications using LED. This thesis proposed two different designs for individual applications in illumination. The design of polarized light source is not same as conventional design for general LED source. The conventional design may be only focused on extraction efficiency or angular emission profile, this design extra improves the utilization efficiency of polarized light. This design is also applied for LED direct type backlight module. The angular profile of light source makes the illumination of target plane uniform, and the utilization efficiency of polarized light is higher than general LED light source in direct type backlight module. This thesis has been completed for designing two kinds of polarized LED modules. The first design uses DBEF as polarization component in module; the second design uses wire-grid polarizer. The first design has been fabricated and measured. The other lighting design is used in shadow-free illumination. The advantages of shadow-free illumination using LED are better than conventional light bulb. Because it is medical application, the design complies with ISO 9640. This thesis has been also completed for designing two kinds of dental lightings in shadow-free illumination field. The first design uses many LED types for light sources; the second design uses one LED type. The second design has been fabricated and measured. LightTools is the major non-sequential software used for design and simulation. This work uses not only photometry, but also calculation of color rendering index.