Display device
A display device comprises a housing, an image capture device and a screen mounted to the housing. A drive platform is mounted to the housing. The drive platform comprises: a rotatable part to which the image capture device is mounted; a stationary part having a chamber to receive the rotatable part and a capture window to expose the image capture device; and at least one piezoelectric motor which rotates the rotatable part to pan and tilt the image capture device within the capture window.
1. A display device comprising: a housing; a screen mounted to the housing; an image capture device; and a drive platform mounted to the housing, the drive platform comprising:
a rotatable part to which the image capture device is mounted, the rotatable part being like a sphere;
a stationary part mounted to the housing, the stationary part comprising a spherical chamber in which the rotatable part is received and a capture window through which the image capture device is exposed, and
two piezoelectric motors arranged to rotate the rotatable part about two axes, to move the image capture device with respect to the housing, each piezoelectric motor comprising a piezoelectric element having a friction nub which contacts and drives the rotatable part to move the image capture device within the capture window;
wherein the two piezoelectric elements are disposed on opposite sides of a plane passing through a spherical center of the rotatable part, so that the rotatable part rotates about a first axis of said two axes when the two friction nubs move in an identical direction, and the rotatable part rotates about a second axis of said two axes when the two friction nubs move in opposite directions.
2. The display device of claim 1 , wherein the drive platform comprises two springs to urge the two piezoelectric motors so that the friction nubs elastically contact the rotatable part.
3. The display device of claim 2 , wherein each piezoelectric motor and each spring are disposed inside the stationary part so that the drive platform is an independent functional module.
4. The display device of claim 1 , wherein the two piezoelectric elements of the two piezoelectric motors are substantially parallel, the plane defined by the two piezoelectric elements passing through the spherical center of the rotatable part.
5. The display device of claim 1 , wherein the two piezoelectric elements are symmetrically located about a plane which passes through the spherical center of the rotatable part.
6. The display device of claim 1 , wherein the two piezoelectric elements are symmetrically located about a plane which passes through the spherical center of the rotatable part and the center of the capture window.
7. The display device of claim 1 , wherein the two piezoelectric elements of the two piezoelectric motors are located in a plane which passes through the spherical center of the rotatable part, the two piezoelectric elements forming an included angle ranging from 0 to 180 degrees.