PURPOSE: To avoid the dropout of the readout information, by rotating a disk, etc. at an equiangular speed, converting the output of a reading head into a frequency corresponding to the position of the head by a head position-frequency converting means when the circumference of the disk is scanned and equalizing the output of the head.
CONSTITUTION: A discoidal information medium 7 is rotated by a mechanism 8, and a reading head 9 projects the luminous flux given from a light source on the disk 7. Then the reflected light 10 is received at the head 9 and then subjected to the photoelectric conversion. Thus the head 9 reads the information. A head position-voltage converter 15 produces the voltage proportional to the distance from the center of rotation or the most outer circumference of the disk 7 via a head position detecting mechanism 14 which is connected directly to the head 9. A voltage-frequency converter 16 oscillates a pulse signal of a frequency proportional to the control voltage of the converter 15. The pulse signal of the converter 16 and the detecting signal of the head 9 are fed to a signal processing circuit 18 via an AND gate 17. The signals 21, 21' and 22" having the same data length on different circumferences of the disk 7 are replaced with the signals having the same pulse respectively and then can be drawn out in the form of the equivalent information.
SAKAMOTO MASAHARU
KODAMA HIROSHIGE
YAMAMIYA KUNIO
KATOU KIICHI
OOSHIMA KEN
| JPS5169614A | 1976-06-16 | |||
| JPS55125516A | 1980-09-27 | |||
| JPS57208639A | 1982-12-21 |