  Spontaneous transverse mode locking to generate optical vortex arrays is
already widely studied for the frequency degenerated transverse modes. While,
the mode locking between transverse modes in different orders (non-frequency
degenerated families) to achieve spatial stationary beam patterns is rarely
reported. The theory of transverse mode locking is discussed. Concepts of
general transverse mode locking (G-TML) and restricted transverse mode locking
(R-TML) are mentioned. It's experimentally shown that R-TML is possible in
microchip cavities with high nonlinearity. More interestingly, some Chinese
characters like laser modes can be generated by microchip lasers with this
special transverse mode locking effect. And various experimental results and
corresponding simulations are presented.
