frequency doubled diode pumped solid state laser coherent verdi is imprinted with phase only holograms using a liquid crystal spatial light modulator slm hamamatsu x8267 ppm the modified laser beam is relayed to the input pupil of a 100 u00d7 na 1 4 splan apo oil immersion objective mounted in an inverted optical microscope nikon te2000u which focuses it into optical traps the same objective lens is used to form images of trapped objects by using the microscope 39 s conventional imaging train as a soft fabrication technique holographic assembly requires substantially less processing than conventional methods such as electron beam lithography and can be applied to a wider range of materials assembly with holographic optical traps lends itself readily to creating nonuniform architectures e g microstructural arrangements articles of manufacture and compositions of matter with specifically engineered features such as the channel embedded in the octagonal domain in fig1 d such structures can for example act as narrowband waveguides and frequency selective filters for visible light holographic trapping 39 s ability to assemble free form heterostructures extends also to three dimensions the sequence of images of a rolling icosahedron in fig2 a d show how the colloidal spheres 39 appearance changes with distance from the focal plane this sequence demonstrates that holographic.