| 摘要 |
The automatic focusing controller for a video camera includes light receiving means for receiving light reflected from an object, a current-voltage converter for converting the current signal of the light receiving means into a voltage, an amplifier for amplifying the voltage of the current-voltage converter, a rectifier for converting the AC of the amplifier into DC, a voltage-frequency converter for converting the voltage passing the rectifier into frequency, a microprocessor for comparing the frequency of the voltage-frequency converter with a reference frequency and controlling a motor driving means according to the value, a switch turned on or off by the microprocessor, an infrared LED driving means for transmitting infrared rays into the object, and a motor driving means for automatically focusing according to an object distance, thereby enhancing reliability of the system.
|
