In this paper, we propose a hologram reconstruction algorithm with techniques which can effectively reduce
reconstruction errors caused from reconstruction process and external damages of the kinoform CGH ID tag. The 11-
level kinoform computer generated hologram (CGH) patterns which are generated by modified simulated annealing are
recorded on a texture paper by a photo printer, and retrieved by a digital camera. Through suitable reconstruction
program and image processing in computer, the captured hologram patterns on the ID tag are reconstructed with a low
error rate of about 4%, compared to the original data prior to the kinoform CGH pattern. It is also shown that our robust
reconstruction algorithm can considerably reduce reconstruction errors for damaged tags. The original image has been
actually reconstructed at a low error rate of about 8% and 12% from a 25% and 50% damaged tag, respectively.
As an application in the backlight system of small LCD display, we realized a pure white light source by mixing red, green, blue (RGB) lights using a 3 X 3 Hard Plastic Cladding Fiber (HPCF) coupler. We also proposed the 0.44 inch LED backlight system with these fiber-optic pure white sources and characterized its illumination characteristics.
Using optimized fusion-tapering technique, we fabricated HPCF coupler which combines three input lights over the circularly formed waist. HPCF has the core diameter of 200 μm and clad diameter of 230 μm. The fabricated 3 X 3 HPCF coupler has the perfect uniformity of about 0.3 dB, low insertion loss of 5.5 dB, and low excess loss of 0.8 dB, which shows excellent uniform power splitting ratio.
In order to improve the transmission performance, The RGB chip LEDs were butt-coupled directly to the ferruled input ports of the coupler and packaged by TO46-can type. In the produced white color by HPCF coupler, the photometric brightness at the circular endface of outputs of HPCF coupler was in a rage of 10062 ~ 10094 cd/m<sup>2</sup>.
The fiber optic white color combiner provides tunable white sources excluding heat source and having thickness of 200 μm. We also proposed a 0.44 inch LED backlight system with these fiber-optic pure white sources. With the proposed device, we obtain the improved uniformity in luminance distribution and wide color gamut by using the white light mixing red, green and blue lights.