摘要 |
<p>Optical fibre amplifiers (3), such as those used in optical information transmission systems, for example those with Er<3+>-doped optical waveguides, are strongly dependent on wavelength amplification in the wavelength range concerned. According to the invention, the emission wavelength ( lambda 0) of the semiconductor laser (1) of an optical transmission system is adjusted by a control device provided in the optical transmitter (20) to the wavelength at which the optical fibre amplifiers (3) produce maximum amplification. The control device finds the optimum wavelength by evaluating the light absorption of an optical waveguide reference piece (9) whose maximum lies on the same wavelength as that at which the optical fibre amplifier (3) attains its maximum amplification, and by adjusting the emission wavelength of the laser (1) to the wavelength of the maximum absorption in the optical waveguide reference piece (9). <IMAGE></p> |