optical symmetry
3.By applying the energy matrix elements,including coulomb interaction and spin orbit coupling,of the strong field coupling scheme for d 2(d 8) electron configuration in trigonal crystal field and adopting the method of complete diagonalization,we calculate the optical spectra and the EPR spectrum of Ni 2+ :LiNbO 3 with C 3V symmetry.
7.A pair of optical paths of SLM is denoted by a group of basic points and basic planes, and then two models of micro stereovision with SLM are derived via the geometrical projection of virtual incident rays and the weak nonlinear phenomenon. The symmetry of a pair of optical paths of SLM is considered in the first model, and the weak difference is considered in the second model.

