Electrically controllable all-optical switches using dye-doped liquid crystal cells with buckypapers

This work fabricates an electrically controllable all-optical switch using a dye-doped liquid crystal (DDLC) cell on which is pasted a buckypaper. The buckypaper serves as a thin film resistant heater; it can maintain the temperature of the DDLC cell constant by environmental cooling. The threshold power of the DDLC cell, which is the input optical power at which the output optical power begins to fall, is controlled by applied voltages, and the switch-off power of the cell, which is the minimum input optical power at which the output optical power falls to zero, is also controlled by the applied voltages. Therefore, such a cell can be developed into optical limiting devices with adjustable threshold and switch-off powers for multi-purpose use.