An optical pulse code recognition device and an optical distributor recognize
multiple bits of a 1 Tbps packet signal as they are, all at one time. A serial
signal light emitted from an optical fiber is collimated by a lens and applied
onto a mask having a mask pattern. A thin film optical switch increases its optical
transmittance when irradiated with a control light, allowing the collimated signal
light to transmit through it. When the control light is applied, the transmitted
collimated signal light is converted into a parallel signal. The mask pattern has
multiple transmission portions allowing one bit of signal light to transmit through
and an equal number of non-transmitting portions to block the light, and whether
or not a bit pattern of the signal light and the mask pattern match each other
is found by detecting a maximum or minimum value of light intensity with a photodetector.
