| 摘要 |
PURPOSE:To simplify the constitution by moving straightforwardly a 4-split sensor to make the output difference of two elements of the opposite areas zero after the sensor is turned based on the absolute value difference of the said output difference to attain position adjustment of an objective lens without forced vibration. CONSTITUTION:An operating section 16 operates ¦A-B¦-¦C-D¦ and gives an output to an operation section 17 based on the output difference A-B of the opposed areas 7a, 7b of the 4-split sensor 7 and the output difference C-D of the opposed areas 7c, 7d. The result operated based on the input data of the operation section 17 is outputted to a discrimination section 18, where the turning direction of the sensor 7 is discriminated. A drive command signal representing the discriminated turning direction of the discrimination section 18 is outputted to a circuit 19, a motor 20 is driven and the sensor is driven to change the position. When the center point O' of the sensor 7 is coindicent with a 2-split line of the quadrant where the position O' is positioned, the drive command signal is outputted to a circuit 25 based on the differences A-B and C-D by the operating section 16, the motor 26 is driven to move straightforward the sensor 7, the differences A-B, C-D are zero to complete the alignment adjustment of the sensor 7. |
