SURFACE CHARACTERISTIC DETECTOR

摘要

PROBLEM TO BE SOLVED: To read a bar code and to detect the surface characteristics and writing area of a writing surface by utilizing the characteristics of a pen type input device. SOLUTION: At the time of bringing the pen tip 3 of the pen type input device 1 into contact with the writing surface provided with the plural areas of different friction coefficients and surface coarseness and moving it, the output signals of acceleration sensors 4a-4c are sent to an arithmetic part 5. The arithmetic part 5 extracts high frequency components from the output signals of the acceleration sensors 4a-4c and obtains friction signal components. The difference of the friction coefficient and surface coarseness of the writing surface where the pen tip 3 is moved is obtained from the amplitude and frequency of the friction signal components, the change is detected and in which area of the writing surface the pen tip 3 is present is detected.