A positioning apparatus converts linear movement along a first axis into either linear movement along another axis or rotational movement. The apparatus includes a fixed element and one or more moveable elements which are moveable relative to the fixed element. A first guide element is attached to the fixed element and a second guide element is attached to the moveable element. An adjustment mechanism, which is associated with the first and second guide elements, is moveable relative to the fixed element along a first axis, and movement of the adjustment causes movement of the moveable element.