Patent · US Expired

Light diffusion film, plane light source device and liquid crystal display apparatus for enhancing a constant luminance and diffusing a light

US6917396B2 · kind B2 · utility

48Cited by
5References
24Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 30, 2002
Grant dateJul 12, 2005
Priority date
Expiry dateMay 30, 2022

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC09K2323/00
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A transmissive display apparatus comprises a liquid crystal display unit; and a plane light source unit that comprises a tubular light source, a light guide, and a light-diffusing film having anisotropy that provides a consistent luminance in a display surface, and/or ultraviolet (UV) absorbability that absorbs the UV from the light source and prevents deterioration of a prism sheet in the display unit and liquid display cell. In the film, a light-scattering characteristic F(θ) represents a relationship between the light-scattering angle θ and a scattered light intensity F fulfills Fy(θ)/Fx(θ)≧1.01 over a range of θ=4 to 30°, wherein Fx(θ) and Fy(θ) represent the light-scattering characteristics in an X-axial direction and Y-axial direction of the film, respectively. The film comprises a light-diffusing layer composed of a plurality of resins which are different from each other in refractive index, and a transparent layer laminated on at least one side thereof.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.