| 摘要 |
PURPOSE:To determine the noise characteristics in a short time, by measuring the oscillation spectrum of a semiconductor laser, and obtaining the mode ratio between the intensity at the maximum peak and the intensity at the secondly intensive peak adjacent to the maximum peak. CONSTITUTION:When the slow starter power source is turned on, the semiconductor laser 14 to be measured oscillates, with its emission light entering a photo- spectrum analyzer 15; then the analizer indicates the spectrum of the oscillated light. The ratio X/Y (mode ratio) between the intensity X at the maximum peak and the intensity Y at the secondly intensive peak adjacent to the maximum intensity X of the spectrum is obtained, with the result that the noise characteristics is determined in a short time since the smaller the mode ratio, the better noise characteristics has the semiconductor laser 14. |
