Abstract: A system for detecting contact of an object with a display. The system may include a light emitting sheet on the display, the light emitting sheet being configured to emit light when the object is in contact with a point on the sheet and an optical detector in the display, which may be used to detect the emitted light and to locate the point of contact.

Abstract: Embodiments of the present invention provide for an array, and corresponding method of forming an array, that includes a plurality of light emitting devices. The light emitting devices are disposed over a substrate, and a photodetector detects light emitted through the substrate from the light emitting devices. Further, a substantially constant brightness may be maintained in a plurality of light emitting devices disposed over the upper surface of a substrate in an array. Light emitted through the substrate from each of the light emitting devices is measured, and the voltage level applied to each of the light emitting devices is varied to maintain a substantially constant brightness level of light emitted from the light emitting devices.