Figure 20.5 — Holographically assembled quasicrystals Figure 20.5 — Holographically assembled quasicrystals. (a) five-fold, (b) seven-fold and (c) eight-fold colloidal quasicrystals organised using holographic optical tweezers. (d) five-fold axis, (e) two-fold axis, (f) five-fold axis and (g) midplane view of a rolling colloidal icosahedron realised using holographic optical tweezers. In all cases the particles are 1.53 μm-diameter silica spheres immersed in water. Bottom row: a sequence of images of a trapped particle moving through a focal plane used for colibration of the digital video microscopy.Reprinted from Roichman and Grier, Opt. Express 13, 5434–9. Copyright (2005) The Optical Society.