Eyes, cameras, and standard microscopes can only see objects that scatter or absorb light because they measure the intensity, or time-averaged amplitude, of light. However, phase imaging techniques, like the one developed in the Caltech Biophotonics Laboratory, can capture information hidden in the wave nature of light—its phase. The phase of light carries information about material thickness and composition (even from transparent objects!), allowing biologists to discern cell features like organelles without having to stain them. The usefulness of this technique is shown by the stark contrast difference between the phase image (lower left) and intensity image (inset, upper right) of the starfish larva.