Apparatus and method for measuring distances on a surface according to a designated scale

An apparatus for measuring distances on a surface according to a designated scale includes: (a) a distance indicating unit for indicating distance between a first locus and a second locus on the surface; (b) a calibration unit coupled with the distance indicating unit for effecting calibration of the apparatus to the designated scale; (c) a control unit for controlling at least the calibration; the control unit being coupled with at least the calibration unit; and (d) a display unit for displaying information relating at least to the calibration and the distance; the display unit being coupled at least with the control unit. At least the control unit, the distance indicating unit and the display unit cooperate to indicate the distance according to the designated scale after the calibration.