Patent · US Active

Direct type back-light device

US7887208B2 · kind B2 · utility

5Cited by
1References
24Claims
0Family size

Assignee

Inventor

Key dates

Filing dateSep 15, 2006
Grant dateFeb 15, 2011
Priority date
Expiry dateApr 6, 2027

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG02F1/133607
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A direct type back-light device comprising: a reflection plate; a plurality of linear light sources disposed in parallel; and a light diffusion plate disposed, in this order, in which the light diffusion plate includes on at least one main surface a plurality of concave or convex structural units each having three or more sloped sides, has a maximum height Rz of the main surface having the structural units being not more than 1000 μm, and in a vertical cross section of the light diffusion plate, which lies immediately above a region between central axes of adjacent linear light sources and in which a direction perpendicular to a central axis direction of the linear light source is defined as a cutting-plane line, includes a portion: in which the number of lines representing the sloped sides n of which gradients Xn (unit:degree, where n is a natural number and is a subindex for representing each sloped side) differ is 2 or more, and in which all gradients Xn have, between an average distance aL(mm) between the central axes of the adjacent linear light sources and a minimum distance bL(mm) between the central axis of the linear light source and the main surface facing the linear ligh…

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