High gain diffuser film with surface relief of 2D paraboloidal lens array

Abstract

A novel micro-structure diffuser film, paraboloidal lens array film (PLAF), was provided for the backlight module of liquid-crystal display (LCD). PLAF, which enables both of light-collecting and diffusing abilities, has the similar functions to BEFs and diffusers. PLAF with periodic paraboloidal lens array enhances on-axis intensity achieved to 155% along the normal direction. In addition, PLAF subject to random lens pitches performs 134% on-axis intensity and 50% full width at half maximum (FWHM) increase compared with conventional diffuser in bidirectional transmittance distribution function (BTDF).