Patent ID: 7423564
Filing Date: 2008-09-09
Classification: G02F,H04B

Abstract:
1. An optical signal processing method for optically analog-to-digital-converting an optical analog signal into an optical digital signal, the method including the steps of: optically sampling the optical analog signal using a sampled signal having a predetermined sampling frequency, and outputting control light having a pulse train of optically sampled optical analog signal; generating a pulse train of signal light which is synchronized with the sampled signal and has a first wavelength; and optically encoding the pulse train of the signal light according to the control light having the pulse train of the optically sampled optical analog signal, by using a plurality of optical encoders each including nonlinear optical loop mirrors having input-to-output characteristics with different periodicities with respect to light intensity, and outputting a plurality of pulse trains of optically encoded signal light from said optical encoders, respectively; and performing optical threshold processing on the plurality of pulse trains of optically-encoded signal light to optically quantize the plurality of pulse trains of optically-encoded signal light, by using at least one of optical threshold processors each of which is connected to each of said optical encoders and includes a nonlinear optical device having a nonlinear input-to-output characteristic with respect to light intensity, and outputting optically quantized pulse trains as optical digital signals.