摘要 |
An optical analogue to digital (A/D) converter for converting an input analogue voltage signal into a digital output, comprising means for frequency modulating an optical signal with an input analogue voltage signal, delay means for splitting the frequency modulated optical signal and generating at least one differentially delayed signal and at least one reference signal, at least one combining means arranged to combine the or one of the delayed optical signals with the or one of the reference signals, and at least one converter means for converting a combined signal output from an associated one of the combining means to a digital code. Also provided is a digital optical wavemeter for generating a digital representation of the wavelength of an input optical signal, comprising delay means for splitting the input optical signal and generating at least one differentially delayed optical signal and at least one reference signal, at least one combining means arranged to combine the or one of the delayed optical signals with the or one of the reference signals, and at least one converter means for converting a combined signal output from an associated one of the combining means to a digital signal. |