Patent ID: 7268539

Claim:
A pulse signal generator which comprises means having a number of pits and projections and generates pulses according to the behavior of the projections and pits of the means, the means being capable of moving the pits and the projections in a first direction sequentially in given order or moving the pits and the projections in a second direction sequentially in reverse order of the order in the first direction, the pits and the projections being disposed in the moving direction alternately at equal spaces with some of the projections missing or some of the pits filled, wherein the value of the ratio between the time interval of pulses generated by portions other than a projection-missing portion and the time interval of pulses generated by the projection-missing portion or the value of the ratio between the time interval of pulses generated by portions other than a pit-filled portion and the time interval of pulses generated by the pit-filled portion differs between when the pits and the projections move in the first direction and when the pits and the projections move in the second direction.