Patent ID: 7804606

Claim:
A portable electronic device for measuring a distance (D 1 ) between two points (E 1 , E 2 ), the portable electronic device comprising: a first surface facing and parallel to a line defined by the two points (E 1 , E 2 ); a measuring unit disposed at the first surface for measuring a distance (D 2 ) between the first surface and the line; a visible light emitter disposed at the first surface for generating a visible light beam and an initial direction of the visible light beam is substantially perpendicular to the first surface and the line defined by the two points (E 1 , E 2 ); a motor connecting with the visible light emitter for rotating the visible light emitter from the initial direction to pointing in another desired direction; an angle calculating unit for computing a first angle defined by the visible light beam striking the point (E 1 ) and the initial direction, and a second angle defined by the visible light beam striking the point (E 2 ) and the initial direction according to a rotated angle of the motor; a computing unit for computing the distance (D 1 ) between the two points (E 1 , E 2 ) base on the distance (D 2 ) and the first and second angles; and an output unit for outputting the distance (D 1 ).