Optical-spectrum-encoded analog-to-digital converter

A novel optical-spectrum-encoded(OSE) analog-to-digital converter(ADC) is proposed in this letter. To simply exemplify the conversion idea,a 5-bit device structure consisted of Fabry-Perot interferometers(FPI) is analyzed and numerically simulated. The dependence of peak-transmission wavelength on modulation voltage in an electro-optical FPI and the dependence of transmitted power on incident light wavelength in an FPI are discussed and utilized to implement OSEADC. A linearly tunable mode-locked laser,as a voltage-wavelength transformer and a sampler,and chirped grating FPIs,as an encoder array,can be used to obtain much greater sampling rate and bit-resolution.