Patent ID: 6614588
Filing Date: 2003-09-02
Classification: H04B

Abstract:
An optical amplifier comprising:an optical repeater circuit for amplifying and repeating input optical signals, a bypass circuit for controlling the amount of the drive current to drive said optical repeater circuit on the basis of a setting signal, an optical repeater means which is formed by connecting a plurality of pairs of said optical repeater circuit and said bypass circuit in series, or in parallel and in series altogether, a voltage limiter circuit which is connected to said optical repeater means in parallel and limits the voltage applied to said optical repeater means, and a current detection means, which is connected in series to a parallel circuit composed of said optical repeater means and said voltage limiter circuit, detects the current amount fed to said parallel circuit, generates a setting signal to said bypass circuit in accordance with the amount of the fed current thus detected, and wherein said optical repeater circuit amplifies said input optical signals in a plurality of output levels according to said setting signal.