Seung-ho Nam

Novel MEMS variable optical attenuator with expanded core waveguides

A novel variable optical attenuator is proposed. It is composed of the planar waveguides and a comb actuator with light blocking bar. The waveguides are gradually expanded such that the single mode operation is maintained.

P‐76: Highly Efficient Backlight Unit with a Polarization‐Separating Anisotropic Layer

We have developed a highly efficient backlight unit (BLU) with a polarization-separating anisotropic layer on which asymmetric microstructures were embossed. Our BLU provides the polarized light along the direction normal to the anisotropic layer and has over 30% higher luminance than a BLU adopting a reflective polarizer.

Polarized Light Out-coupling in Backlight by Collimating the Beam into Lightguide Plate

Abstract We developed a new configuration of polarized light out‐coupling lightguide plate (LGP) in the LCD backlight. By collimating the light into the LGP, one linear polarization component experienced total internal reflection at the planar interface of LGP and anisotropic layer, whereas the orthogonal polarization was out‐coupled along the normal direction through a birefringent layer and subsequent isotropic microstructures.

Design of a Highly Efficient Lightguide Plate Using an Anisotropic Layer with Polarization-Separating Microstructures

We developed a highly efficient lightguide plate (LGP) using an anisotropic layer (AL) with polarization-separating microstructures. The microstructures were fabricated on a uniaxially stretched polymeric AL through a hot embossing process. Our LGP with asymmetric saw-tooth bistructures produces highly efficient polarized light along the direction normal to the AL by reducing the stray light propagating at large inclination angles. The backlight unit (BLU) with a newly designed LGP has about 30% higher luminance and integrated intensity than the conventional BLU with a reflective polarizer.