A DUAL MODE DISPLAY WITH A BACKLIGHT FILTER FOR AN UNACTIVATED LIGHT EMITTING DIODE (LED)

• Main Authors: GROSSMAN, STEVEN, A, CAMPBELL, WILLIAM, T, MANER, RANDY, M
• Format: Patent
• Language: English; French; German
• Published: 02.05.2012
• Subjects: DEVICES OR ARRANGEMENTS, THE OPTICAL OPERATION OF WHICH ISMODIFIED BY CHANGING THE OPTICAL PROPERTIES OF THE MEDIUM OF THEDEVICES OR ARRANGEMENTS FOR THE CONTROL OF THE INTENSITY,COLOUR, PHASE, POLARISATION OR DIRECTION OF LIGHT, e.g.SWITCHING, GATING, MODULATING OR DEMODULATING; FREQUENCY-CHANGING; NON-LINEAR OPTICS; OPTICAL ANALOGUE/DIGITAL CONVERTERS; OPTICAL ELEMENTS, SYSTEMS, OR APPARATUS; OPTICAL LOGIC ELEMENTS; OPTICS; PHYSICS; TECHNIQUES OR PROCEDURES FOR THE OPERATION THEREOF

A dual mode or multimode backlight containing LEDs as a light source. The backlight has light cavity containing a reflective material. The cavity has an opening to allow light to be directed to a display source such as a liquid crystal display (LCD). Two sets of LEDs are provided, one set for day mode and one set for night mode. The night mode LEDs is fitted with an NVIS filter. The day mode LEDs is fitted with a filter that suppresses the phosphorescence from the day mode LEDs. The filter suppress the IR energy and allows maximum luminance from the day mode LEDs. During night mode operation, the backlight is flooded with light. Filtered light from the NVIS LED's would impinge on the day mode LED's causing them to phosphoresce. The filter over the day mode LEDs removes the infrared energy from the phosphorescent light emitted from the day mode LEDs.