Optical waveguide sheet, backlight unit, and portable terminal

摘要

An optical waveguide sheet for use in an edge-lit backlight unit is provided, that allows rays of light to enter the end face and emits the rays of light from the front face substantially uniformly. The optical waveguide sheet includes on the back side thereof: a sticking preventive means; and a plurality of recessed portions falling toward the front face side. The sticking preventive means: a plurality of annular raised portions each provided around each of the plurality of recessed portions and projecting toward the back face side; and a plurality of protruding portions provided scatteredly in a region which does not include the annular raised portions. The optical waveguide sheet is preferably for use as a light guide film having an average thickness of no less than 100 μm and no greater than 600 μm.

主权项

1. An optical waveguide sheet for use in an edge-lit backlight unit, the optical waveguide sheet having a function of allowing rays of light to enter an end face of the optical waveguide sheet and emitting the rays of light from a front face substantially uniformly,
wherein the optical waveguide sheet comprises on a back side thereof a sticking preventive means; and a plurality of recessed portions falling toward a front face side, and wherein the sticking preventive means comprises: a plurality of annular raised portions each provided around each of the plurality of recessed portions and projecting toward the back face side; and a plurality of protruding portions provided scatteredly in a region which does not comprise the annular raised portions; wherein an average height (H3) of the protruding portions from a back face on average level is no less than 2 μm and no greater than 7 μm, wherein an average height of the annular raised portions from a back face on average level is no less than 0.1 μm and no greater than 6 μm, and wherein the average height of the protruding portions is greater than the average height of the annular raised portions.