Through display ultrasonic touch-screen monitor

1. A touch-screen monitor, comprising:

an ultrasonic sensor (“USS”);

a protective platen;

a visual display residing between the protective platen and the USS;

a control system in communication with the USS;

wherein the USS is configured to generate ultrasonic waves that pass through the visual display, to an object in contact with a protective platen, and configured to detect reflected ultrasonic energy passed through the visual display to the USS for detection of the object on the platen, and produce output signals corresponding to the detected reflected ultrasonic energy; and

wherein the control system is configured to compare the output signals from the USS and determine differences between output signals generated at different times.

2. The touch-screen monitor of claim 1 , wherein the USS includes:

an ultrasonic wave generator;

a piezoelectric hydrophone receiver array; and

an ultrasonic TFT receiver array.

3. The touch-screen monitor of claim 1 , wherein the control system configured to interpret the differences between output signals as movement of an object that is contacting the protective platen.

4. The touch-screen monitor of claim 1 , wherein the control system configured to determine a location of an object that is contacting the protective platen.

5. The touch-screen monitor of claim 1 , wherein the protective platen is a polymeric material.

6. The touch-screen monitor of claim 1 , wherein the protective platen is a silane material.

7. The touch-screen monitor of claim 1 , wherein the protective platen is a ceramic material.

8. The touch-screen monitor of claim 1 , wherein the protective platen is glass.

9. The touch-screen monitor of claim 1 , further comprising a signal processor configured to modify signals produced by the ultrasonic TFT receiver array in order to compensate for attenuation differences imposed by variations in the visual display.