| 摘要 |
PROBLEM TO BE SOLVED: To provide a light transmission and reception system for reducing influences of return light without using an optical isolator.SOLUTION: The light transmission and reception system comprises a light transmitter 1, and a light receiver 3 connected to the light transmitter 1 via an optical fiber 2. The light transmitter 1 does not have an optical isolator, and includes: a semiconductor laser 12; a bias T18 that gives modulation signals adjusted according to electric signals from a signal generator 20 and a direct current from a direct-current voltage source 14 to the semiconductor laser 12, in which a modulation frequency of the electric signal is set equal to a resonance frequency in the light transmitter 1; and a light modulator 13 for modulating output light to the semiconductor laser 12 according to the modulation signals based on the modulation signals from the signal generator 16 and the direct-current voltage from the direct-current voltage source 17. |
