Patent ID: 7794538

Claim:
A method of forming a colloidal crystal comprising: providing a colloidal suspension of colloidal particles, where said particles have a surface charge; providing a continuous wire substrate; ordering said particles into a colloidal crystalline structure on the surface of said substrate, including: a sedimentation means for electrophoretically directing said particles towards said substrate; an annealing means for actively removing defects concurrently with formation of said sedimentation, where said force is oscillatory in magnitude and the direction of said force is varied between multiple crystallographic axes of said crystal; where said annealing means includes a multitude of hydrophones operable to apply a force to said particles, where one or more hydrophones are positioned on each crystallographic axis, and where said means for annealing defects operates at a faster rate than additional said particles are sedimented from said suspension; and where the rate of both said sedimentation and of said annealing are selected as to result in fewer defects in said crystal than without simultaneously applying said sedimentation and annealing means; continuously mechanically advancing said substrate past the area of the intersection of said annealing oscillations, as to maintain the growth front near said area of intersection of said oscillations, and limiting said sedimentation means in other areas; a means for adding material within the interstitial voids of said colloidal crystal, where said interstitial material is selected from the group of high temperature refractory materials, removing said original colloidal crystal, resulting in a colloidal crystal of air/refractory composition; and packaging said refractory colloidal crystal in a bulb.