Ikuo Onishi

Edge-Light Backlight Unit Using Optically Patterned Film

A novel edge-light backlight unit using an optically patterned film (OPF backlight unit) for liquid crystal displays (LCDs) is composed of a light guide plate bonded to the top of fine lenses formed on the OPF, a diffusive sheet, a reflective sheet and a light source. A viewing-angle-dependent luminance distribution of the OPF backlight unit was controllable by changing the shape of a fine lens used for the extraction of light propagating through a light guide plate and the direction control of radiating light, and a luminance distribution in a radiation plane suitable for LCDs was realized by adjusting the interval between lenses. Moreover, the extraction efficiency of the OPF backlight unit was greater than that of a conventional backlight unit. Thus, the OPF backlight unit was shown to be promising for the realization of a brighter, lower power consumption, slimmer and lighter LCD than conventional LCDs.

P‐99: A Backlight Based on a Laser Diode and Its Design Considerations

We have constructed an edge-lit backlight by using a blue-emitting laser diode, an optical fiber and a YAG-based phosphor. White light output was obtained from the backlight surface. We discuss some design issues and expect a high efficiency and a wide gamut for such a backlight.

Edge-Light Backlight Unit Using Optically Patterned Film with Plural Light-Emitting Diodes Placed on Side as Light Source

In an edge-light backlight unit using an optically patterned film (OPF backlight unit) with plural light-emitting diodes (LEDs) placed on the side as a light source, dark areas are easily generated between LEDs, because the OPF backlight unit mainly uses the total reflection induced by optical patterns formed on the OPF. Such dark areas were eliminated by narrowing the interval between optical patterns between LEDs and widening it near LEDs. By adjusting the interval between optical patterns across the entire area additionally, a luminance distribution in a radiation plane suitable for liquid crystal displays (LCDs) was realized. Moreover, viewing-angle-dependent luminance distribution can be narrowed by adjusting the shape of the lens-shaped optical pattern. Thus, the OPF backlight unit using plural LEDs was shown to be suitable for small-area LCDs.