PURPOSE: To surely detect the position of a scanner while unnecessitating a coordinate sheet concerning a mannual scanning type scanner.

CONSTITUTION: This scanner is provided with an image pickup means 1, sound sources 2a and 2b arranged at two places separated from the image pickup means 1 and generating the sound waves of different frequencies, a sound gathering means 3 gathering sound waves by being arranged for the image pickup means 1, a filter means 4 separating the sound waves gathered by the sound gathering means 3, a speed calculating part 5 measuring the frequency shift of the sound waves separated by the filter means 4 and calculating the relative speed between each sound source 2a and 2b and the image pickup means 1, an integration means 6 time-integrating the relative speed and adding the initial value of the distance between each sound source 2a and 2b and the image pickup means 1 to the integrated value so as to calculate the distance between each sound source 2a and 2b and the image pickup means 1, a position calculating means 7 calculating the position of the image pickup means 1 from the distance between each sound source 2a and 2b and the image pickup means 1.