A display that includes energy sensors within the display itself is
disclosed. An Organic Light Emitting Diode (OLED) can be made to operate
both as a light emitter and as an energy detector. When forward biased
with an appropriate driving signal, the OLED emits light via
electroluminescence, which can be used to make a portion of an image on
the display. In another mode, the OLED can detect energy by converting
incoming photons or energy into an electrical signal by the photoelectric
effect. By operating OLEDs in the display in both emissive and sensing
modes, energy that shines on the display, such as from an outside source
can be detected at the same time an image is shown. Additionally, a
display including OLEDs can detect light energy generated by the display
itself.