Analog modulating and driving circuit for semiconductor laser

Patent

Analog modulating and driving circuit for semiconductor laser

- 16 Feb 1983

7

TL;DR: In this paper, the authors proposed to suppress speckle noise on an optical transmission line, by switching a semiconductor laser with a frequency which is sufficiently higher than an analog modulation signal, to oscillate the laser in multiple modes.

Abstract: PURPOSE:To suppress the speckle noise on an optical transmission line, by switching a semiconductor laser with a frequency, which is sufficiently higher than an analog modulation signal, to oscillate the laser in multiple modes. CONSTITUTION:A semiconductor laser driving circuit 1 receives the high frequency from a high-frequency oscillating circuit 2 and the modulation signal, which is obtained by amplifying a modulation signal 3 in a modulation signal amplifying circuit 4, to drive a semiconductor laser 5. The laser light emitted from the semiconductor laser 5 is introduced to a proper optical transmission line. It is necessary that the high-frequency oscillating circuit 2 has a frequency which is sufficiently higher than the analog modulation signal 3 and has a period shorter than the time of holding of multimode oscillation even if the driving current exceeds the threshold.

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Citations

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