O/E converter

Opto-electrical converters (O/E converters) convert light signals into electrical signals. Since optical transmission deals with very low light levels, phototransistors, photodiodes and avalanche photodiodes ( APD) are used for the conversion. Silicon diodes are used for the short wavelength range up to 850 nm near the optical window, while indium gallium arsenide ( InGaAs) is preferred for the wavelength of 1,300 nm.