Patent attributes
A fine adjustment mechanism includes a first frame, a carrying portion and a first connecting portion. The first frame has a first opening. The carrying portion is adapted to assemble outside an optical element for fixing it. The carrying portion has a carrying plate disposed in the first opening and extends from the first opening towards a side of the first frame. The first connecting portion is located in the first opening and connected between the carrying plate and the first frame. The first connecting portion is capable of generating an elastic torsion around the axis in a first direction. By using the theorem of elastic torsion, the present invention makes the carrying portion rotate around the axis of the first connecting portion only and is able to avoid the offset problem occurred at the intersection of the axes of the carrying portion and the first connecting portion during adjusting.