Abstract:

Emerging optical elements with micro-structured patterns can spatially modulate the phase distribution of the light passing through and have been demonstrated in applications such as broadband collimation1, holograms2, and laser processing3. With the increasing interest in adopting micro-LEDs for display applications, microlenses with rationally designed surface profile are used to enhance display brightness and improve the display’s angular emission performance. Traditional mass fabrication methods of spherical microlens, such as thermal reflow and machining, suffer from imprecise control of the light phase. Although some groups have demonstrated the ability of large-area fabrication of aspheric micro-devices4, there are limited records of high-throughput manufacturing of aspherical microlenses for customized micro-LEDs.

In this present, I will present the full design and fabrication flow for the production of such free-form microlens devices, which comprehends optical design, master fabrication by 4096-stage direct laser writing lithography patterning on 4-inch Si wafers, the pattern transfer by UV NIL lithography on glass substrates and the optical characterization of the final product. This process provided both precise morphology and high throughput. It has the potential to be widely applied in the industrial production for the performance enhancement of mirolenses and other microsized optical elements.

ALL INTERESTED ARE WELCOME