Control device for audio-visual display
A control device signals user inputs to an audio-video display. The control device may be configured as a pillow speaker and include a speaker for reproducing audio from the audio-video display. The control device is coupled to the audio-video display by wiring. Shared signals in the wiring are used to provide power to operate the control device and are used to signal the user inputs to the audio-video display. A touch panel is used to sense user inputs. The touch panel may be transparent with an underlay containing indicia of user-selectable commands located below the touch panel. The arrangement and selection of commands available to the user may be modified by changing the underlay.
1. A control device for an audio-visual display, comprising:
a touch panel configured to sense inputs from a user;
a processor coupled to the touch panel and configured to transmit control signals to the audio-visual display based on the sensed inputs, wherein the control device receives power from the audio-visual display via wiring, and wherein the control signals are transmitted over the wiring; and
an energy harvesting circuit configured to receive the power from the audio-visual display and produce a voltage signal for operation of the control device.
2. The control device of claim 1 , wherein the touch panel is transparent.
3. The control device of claim 2 , further comprising an underlay disposed under the touch panel, the underlay including indicia of commands selectable by the user.
4. The control device of claim 3 , wherein the underlay further includes an identifier indicative of a spatial arrangement of the indicia of commands, and wherein the control device further comprises means for reading the identifier.
5. The control device of claim 4 , wherein the control signals are further based on the identifier.
6. The control device of claim 5 , wherein the processor is further configured to control the touch panel by sensing x-axis and y-axis locations of the inputs from the user.
7. The control device of claim 6 , wherein the transmitted control signals correspond to commands associated with the indicia at the x-axis and y-axis locations.
8. The control device of claim 1 , wherein the touch panel comprises a liquid crystal display.
9. The control device of claim 1 , further comprising a speaker configured to produce sounds corresponding to an audio signal received from the audio-visual display.
10. The control device of claim 1 , wherein the energy harvesting circuit receives the power using a data signal and a common signal.
11. The control device of claim 10 , wherein the energy harvesting circuit comprises a Schottky diode bridge coupled to the data signal and the common signal.
12. The control device of claim 10 , wherein the control signals are transmitted by selectively presenting a low impedance between the data signal and the common signal.