Micrometer scale resonators have attracted a lot of interest of engineers and scholars for commercial applications and scientific research. Primary application would be the light emitting devices like lasers and LEDs. Quantum optical properties like enhanced spontaneous emission and strong coupling between photon and exiton have also been hot subjects of scientific research. Based on the structure of semiconductor surface-emitting lasers, quantum and classical optics on the subjects is presented. Its theories and experiments are described in such an easy way for the beginning researchers to...