Optical Amplifiers are essentials components in long haul fibre optic system. An amplifier is a electronic device that can increase the power of signal. An Optical Amplifier is effectively the opposite of attenuator while Optical Amplifiers provide gain and attenuator provides loss. When a signal travels in a optical fibre medium the signal suffer from various losses such as fibre losses, attenuation losses, fibre splice losses, reduce these losses use the Semiconductor method with saturated and unsaturated Amplified Spontaneous Emission. It reduces the phase shift and recover original signal.