SECONDARY DISPLAY USING PDLC
A secondary display is provided on, in, or under the case of an electronic device at a location convenient for viewing. The secondary display includes PDLC and a backlight. The backlight is preferably either an electroluminescent panel or an array of light emitting die. In the latter case, a transflector is located between the light source and the PDLC.
1 . In an electronic device having a display, the improvement comprising:
a secondary display at a location convenient for viewing, said secondary display including PDLC and a backlight.
2 . The electronic device as set forth in claim 1 wherein said backlight is an electroluminescent panel.
3 . The electronic device as set forth in claim 1 wherein said backlight is an array of light emitting die.
4 . The electronic device as set forth in claim 1 wherein said backlight includes at least one light emitting diode and a light guide for spreading the light from the at least one light emitting diode.
5 . The electronic device as set forth in claim 4 wherein said light guide is an edge lit light conducting sheet.
6 . The electronic device as set forth in claim 4 wherein said light guide includes a plurality of optical fibers.
5 . The electronic device as set forth in claim 4 and further including a transflective layer located between the backlight and the PDLC.
6 . The electronic device as set forth in claim 1 wherein said secondary display contains low content information.
7 . The electronic device as set forth in claim 1 wherein the electronic device is a portable computer and said location is visible on an outer surface of the computer.
8 . The electronic device as set forth in claim 1 wherein the electronic device is a cellular telephone.
9 . The electronic device as set forth in claim 1 wherein the electronic device is an instrument panel.