| 摘要 |
PURPOSE:To measure mode distribution characteristics of a laser diode in a state approximate to an actual driving, by applying a PN (Pseudo Noise) pattern to the modulation of the laser diode to be measured in the case of measurement of various parameters necessary to calculate the K value. CONSTITUTION:A laser diode LD is modulated applying a PN pattern 21 of PN (Pseudo Noise) period NT, where N is the bit length of a period of the PN pulse pattern and T is a bit period. The relative value of a power of a specified longitudinal mode to the total longitudinal mode is measured. Line spectrum components and continuous spectrum components of the specified longitudinal mode are measured, and mode distribution characteristics of the laser diode LD are measured according to a coefficient determined by the measured values and N of the PN. By using the PN pulse pattern in this manner, circumstances more approximate to an actual data pattern can be reproduced. |
