Design and realisation of micro-optic lightfield displays

We present a direct-view 3D display device based on principles of integral photography and realized by stacking multiple micro-optic wafers. It displays artistic motifs created by Berlin based artists Dachroth + Jeschonnek. A regular and a chirped microlens array (MLA) having buried aperture layers are designed, to achieve either maximum display resolution or a large viewing angle. The lightfield information of the projected objects are encoded as 2D features in an object mask array (OMA), generated from data provided by backward raytracing with OpticStudio™ and further processed using Python. The MLA projects the corresponding lightfield information of the OMA towards the observer, giving a 3D appearance to the motif. Wafer level optics is used to realize the display. The MLAs are mastered by reflow technology followed by polymer-on-glass replication on 8” wafers. The OMA is generated by chromium coating, photolithography, and wet etching. MLA and OMA wafers are aligned and stacked using a mask aligner. The final device is ca. 2.5 mm thick. Finally, the results of photometric characterisation and a short outlook are presented.