  The optical readout scheme for the length degrees of freedom of the LCGT
interferometer is proposed. The control scheme is compatible both with the
broadband and detuned operations of the interferometer. Interferometer
simulations using a simulation software Optickle show that the sensing noise
couplings caused by the feedback control can be reduced below the target
sensitivity of LCGT with the use of feed forward. In order to improve the duty
cycle of the detector, a robust lock acquisition scheme using auxiliary lasers
will be used.
