Sub-micron diffraction gratings have been used for two LED illumination applications. One is to create a transparent see through luminaire which can be used to illuminate and read a paper document or e-book. A second is a light sensor that can be used in a feedback loop to control a multicolor LED lamp. Optical design and experimental proof-of-principle are presented.
Angular color variation in white, phosphor-converted LEDs causes undesirable yellow rings in the beams of spotlights. We developed an inverse method to design TIR collimators that remove the angular color variation for point light sources and significantly reduce color variation for extended light sources, without the need for facets, holographic foils or scattering surfaces. We performed several numerical simulations to evaluate the performance of this point source method for extended light sources.
In the last years it has been shown that efficient collimator systems for point sources can be designed with the
flux tube method in combination with an optimiser. In this paper it will be shown that this method can be
extended to extended light sources. Various collimator designs for different types of sources will be discussed
that transform the illuminance into imposed distribution.
Beam-shaping optics are used in various optical fields to change the luminous intensity distribution. In this paper a flexible method is presented to design beam-shaping optics with aspherical surfaces transforming the intensity profile of the light beam into any desired profile. The method is applied to a collimator lens that transforms a beam from a Lambertian emitter to a uniform light distribution.
A simple, diffraction limited, optical design for a Holographic Data Storage System with a high numerical aperture and
large field is presented. A system analysis is performed and the design is compared with different current and future
formats for optical data storage.
The design, manufacturing and application of variable liquid lenses are discussed. The interface between the two immiscible liquids that forms the lens can be altered with a voltage. Results are presented of applying this lens in miniature autofocus and zoom cameras, in optical recording and in illumination systems.