  We report on the frequency locking of a frequency doubled Nd:YAG laser to a
45 000 finesse, 87-cm-long, Fabry-Perot cavity using a modified form of the
Pound-Drever-Hall technique. Necessary signals, such as light phase modulation
and frequency correction feedback, are fed direcly to the infrared pump laser.
This is sufficient to achieve a stable locking of the 532 nm visible beam to
the cavity, also showing that the doubling process does not degrade laser
performances.
