The interference of light is one of the most important optical

phenomena in the field of bionanophotonics. At first, we will

summarize its features for the convenience of the later discussion.

The interference is a phenomenon, in which waves of more

than two are superposed together to cause various patterns in

temporal and spatial domains. Since it is based on the superposition

principle described in the previous section, and most of interesting

phenomena appearing in bionanophotonics originate from this

simple principle, here we will consider it generally.