| 摘要 |
<p>PURPOSE: To always obtain a desired frequency characteristic in spite of fluctuation in a source voltage by changing the driving condition of a PWM driving means according to the fluctuating proportion of the source voltage. CONSTITUTION: The absolute position of a correction optical system 11 is converted to a prescribed voltage and inputted to the prescribed input of an A/D converter 6. An A/D converting action is periodically executed based on a control signal from a CPU 3 and the positional information of the optical system 11 is fetched in the CPU as digital data. Then, the output of a deflection sensor 4 and the positional output of the optical system 11 are arithmetically operated in the CPU 3 and the driving quantity of the optical system 11 is calculated. After the driving condition of the optical system 11 is decided based on PWM driving information decided by the information of the sensor 4, a driving coil 10 and a power source battery 1, a pulse whose fixed duty time is maintained is outputted in a fixed term by the interruption action of a PWM timer.</p> |
