Patent attributes
The present invention is a changeable apparatus for different total tracks and a corresponding method. The apparatus reflects a light from a light source at least twice toward predetermined directions. The apparatus comprises plural reflection elements, at least one of the plural reflection elements is a rotational reflection element, which has plural reflection surface sets, and each reflection surface set has at least one reflection surface. The rotational reflective element further comprises a pivot axis is for each rotational reflection element for circulating and changing of reflection surface sets and a fixing apparatus, which connects to a rotational reflection element for adjusting and fixing positions of the rotational reflection element.