Patent ID: 8269123

Claim:
A key pad assembly for an electronic device comprising a plurality of light emitting diodes (LEDs) including a first light emitting diode and a second light emitting diode, a light guide plate for permitting light exiting from the plural light emitting diodes to progress along the light guide plate, a plurality of key buttons provided on the top surface of the light guide plate and composed of a numeral input plate and a character input plate, a plurality of reflective patterns provided on the light guide plate for allowing the light to be reflected toward the key buttons, a plurality of protrusions provided on the lower portion of the plurality of reflective patterns, and a switch substrate having a plurality of switches mounted thereon to correspond to the plurality of protrusions, wherein the numeral input plate of the key buttons is provided at the lower portion of the key button with a color-expressing optical filter layer for selectively responding or not responding depending on the size of the wavelength of light exiting from the first and second light emitting diodes and converting the light into various colors, and wherein the character input plate of the key button is provided at the lower portion of the key button with a first optical filter layer for preventing light having a wavelength ranging from 380 nm to 450 nm from being leaked out, and a second optical filter layer for controlling a white light to be expressed.