Browse Prior Art Database

LCD Backlights Design which Suppresses Light-Guides Warping

IP.com Disclosure Number: IPCOM000123122D
Original Publication Date: 1998-May-01
Included in the Prior Art Database: 2005-Apr-04
Document File: 2 page(s) / 55K

Publishing Venue

IBM

Related People

Ono, M: AUTHOR

Abstract

Disclosed is a mechanical design of a LCD (liquid crystal display) backlight unit. The objection of this design is to prevent problems caused by convex light-guide's warp of LCD backlight unit.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 76% of the total text.

LCD Backlights Design which Suppresses Light-Guides Warping

   Disclosed is a mechanical design of a LCD (liquid crystal
display) backlight unit.  The objection of this design is to prevent
problems caused by convex light-guide's warp of LCD backlight unit.

   The light-guide's warp toward the LCD's glass (convex warp)
causes arc-shaped wrinkles on optical sheets of the backlight unit,
because the center of light-guide presses the sheets to LCD's glass.
The light-guide's concave warp causes wave-shaped wrinkles on the
optical sheets, because the corners of light-guide presses the sheets
to LCD's glass.  But it is difficult to mold a light-guide that has
no warp and the extent of light-guide's warp increases in high
temperature and high humidity environment.  The characteristic of
this design is using a concavely warped light-guide and a frame
structure which suppresses the light-guide warping.

   Fig. 1 shows the conceptual design of this backlight.  A
light-guide of this backlight unit (1) is intentionally molded to
warp in the opposite direction from a LCD's glass screen (concave
warp).  The frame of this backlight unit (2) is designed to make the
light-guide be flat.  A rib of the frame (3) pushes the center of
light-guide in the direction of the LCD's glass screen.  Two
projections of light-guide (4) are inserted into cutouts of the
frame (5), so the warp of light-guide's corners is suppressed by the
frame.  Fig. 2 shows a mechanism suppressing the warp of...