Positioning Device of Pointer and Related Method

A positioning method for positioning an aim point on a screen pointed by a pointer comprising:

• displaying a plurality of characteristic points with known screen coordinate values on a screen;
• forming an aim point at a position on the screen pointed at by the pointer;
• acquiring an image according to the position of the aim point on the screen, wherein a center point of the image corresponds to the position of the aim point on the screen;
• detecting the plurality of characteristic points in the image and calculating image coordinate values of the plurality of characteristic points in the image;
• establishing a transformation matrix according to the known screen coordinate values of the plurality of characteristic points and the image coordinate values of the plurality of characteristic points in the image;
• and
• converting coordinate values of the center point of the image to those of the aim point on the screen for deciding the position of the aim point on the screen according to the transformation matrix.

A positioning device for an image sensor comprising:

• a screen for displaying a plurality of characteristic points with known screen coordinate values;
• an image sensor, for acquiring an image, the image sensor comprising:
• a calculation unit for detecting the plurality of characteristic points in the image and calculating image coordinate values of the plurality of characteristic points in the image;
• and
• a processor, coupled to the screen and the image sensor, comprising:
• a projection matrix generation unit for establishing a projection matrix according to the known screen coordinate values of the plurality of characteristic points and the image coordinate values of the plurality of characteristic points in the image;
• and
• a position decision unit for computing a position and a direction of the image sensor relative to a screen coordinate system according to the projection matrix.

A positioning method for an image sensor comprising:

• displaying a plurality of characteristic points with known screen coordinate values on a screen;
• acquiring an image for detecting the plurality of characteristic points in the image and calculating image coordinate values of the plurality of characteristic points in the image;
• establishing a projection matrix according to the known screen coordinate values of the plurality of characteristic points and the image coordinate values of the plurality of characteristic points in the image;
• and
• computing a position and a direction of the image sensor relative to a screen coordinate system according to the projection matrix.