| 摘要 |
<p>PURPOSE:To prevent error signals from occurring due to fluctuation of a pen shaft by providing the planar part consisting of flat surfaces which so projects as to surround a rotating ball set at the tip of a pen shaft far the purpose of suppressing the fluctuation angles of the pen shaft within a certain range. CONSTITUTION:When a pen shaft 2 is shifted with a ball 1 pressed against a moving surface, the ball 1 so rotates as to make an X rotational body 3 or a Y rotational body 6 rotate. The light from a light emitting element is made to pass through or to be reflected by a slit 4 provided on a disk attached coaxially to the rotational body 3 and so, the rotational amount of the rotational body 3 is measured. At the time of this inputting operation, a planar part 9 is kept to contact a pen shaft moving surface even when the pen shaft 2 fluctuates, so, a fluctuation angle 10 is suppressed to a minimum. Thus, an error signal is rare to take place from fluctuation and input is made with high accuracy.</p> |
