The method works by solidifying a resin that hardens when exposed to light. The resin is solidified into a three-dimensional grid by placing it in the interference pattern set up by four intersecting laser beams. The pores in the resin are then filled with titanium dioxide, which is allowed to set. The resin is then burnt off to create the photonic crystal.

Other techniques for making photonic crystals rely on chemical deposition, or on adapting semiconductor fabrication techniques. However, both of these methods have a number of disadvantages. "Our technique is much more flexible than other methods," says Turberfield. "It is fast, cheap, and very flexible." The technique can also create structures with 10 times as many layers as structures produced by chemical deposition.

The next step, says Turberfield, is to create a material that has the same optical characteristics in all directions, and then introduce defects into the crystal. This will allow a wide range of photonic-based circuits to be fabricated.