| 摘要 |
PROBLEM TO BE SOLVED: To provide a wavelength multiplex transmitter which compensates loss of light beam caused by an EA modulator of a high frequency without increasing the current amount per unit length of DFB semiconductor laser.SOLUTION: "123" represents a wavelength multiplex transmitter module, "122" represents a wavelength multiplex transmitter that is one semiconductor chip, and "121" represents an optical fiber. The semiconductor chip 122 consists of four DFB semiconductor lasers 101 to 104, four electric field absorption (EA) type optical modulators 105 to 108, and one multi mode interference (MMI) type four to one optical multiplexer 113. In other words, the semiconductor chip 122 has four EA-DFBs on which DFB semiconductor lasers and EA modulators are integrated. An oscillation wavelength is shorter than a resonant length in DFB semiconductor lasers 101, 102 corresponding to lane 0, 1 of high frequency, DFB semiconductor lasers are arranged so as to contact with an edge surface opposed to an edge surface which contacts with EA type optical modulators 105, 106, and the oscillation wavelength is equal to the resonant length in DFB semiconductor lasers 103, 104. |
