Abstract
The study deals with the manufacture of multiple-focus micro Fresnel lenses by means of non-rotational diamond cutting tools mounted on an 5-axis control ultraprecision machining center with the positioning accuracy of 1 nm and the rotational one of 0.00001 degree. Micro Fresnel lens consisting of a number of concentric circular microgrooves are in general produced by a lathe. On the other hand, multiple-focus micro Fresnel lens consisting of several micro Fresnel lenses is not notationally symmetric, thus requiring the introduction of 5-axis control ultraprecision machining center. Two-focus and three-focus micro Fresnel lenses are designed and manufactured by controlling the movement of non-rotational diamond cutting edge along the designed micro grooves at the cutting speed of 40mm/min with kerosene dripped as cutting fluid. As a result, the non-rotational diamond cutting method allows multiple-focus micro Fresnel lenses to be manufactured accurately and neatly without any burr generation.
