Patent ID: 6762888
Filing Date: 2004-07-13
Classification: G02B

Abstract:
A control system of zoom lens for a digital still camera which controls zooming of the zoom lens using programmed data written in the micro controller unit (MCU) of the digital still camera, and at the same time controls auto-focusing of the zoom lens with the very mechanism which is used for zoom controlling by receiving electronic signals (pulses) from the MCU or electronically controlled distance measuring system of the digital still camera, comprising:(a) an assembly base on which said control system of zoom lens for the digital still camera is assembled; (b) a first group of lenses, which is assembled in a first lens barrel and placed at the headmost position of said assembly base; (c) a first threaded bearing which is formed as a part of said first lens barrel of said first group of lenses; (d) a first means for position stabilizing said first lens barrel not to rotate; (e) a first stepping motor to drive said first lens barrel; (f) a first screw rod which is provided on and connected to a shaft of said first stepping motor as an extension of the motor shaft and is screwed into a bearing hole of said first threaded bearing of said first lens barrel of said first group of lenses and engages with a thread provided on an inner wall of said first threaded bearing of said first lens barrel of said first group of lenses; (g) a second group of lenses, which is assembled in a second lens barrel and placed next to said first group of lenses; (h) a second threaded bearing which is formed as a part of said second lens barrel of said second group of lenses; (i) a second means for position stabilizing said second lens barrel not to rotate; (j) a second stepping motor to drive said second lens barrel; (k) a second screw rod which is provided on and connected to a shaft of said second stepping motor as an extension of the motor shaft and is screwed into a bearing hole of said second threaded bearing of said second lens barrel of said second group of lenses and engages with a thread provided on an inner wall of said second threaded bearing of said second lens barrel of said second group of lenses; and (l) a third group of lenses, which is assembled in a third lens barrel and placed next to said second group of lenses.