SEMICONDUCTOR LASER DEVICE AND COMMUNICATION SYSTEM USING THE SAME

摘要

PROBLEM TO BE SOLVED: To provide a semiconductor laser device which has a stable lateral mode even when the width of a light emitting stripe region is wide and in which the optical intensity of a far field pattern forms a substantially single lobe. SOLUTION: The semiconductor laser device 1 comprises recesses 4 and 4 each having a depth Lr of 8.2 nm and disposed at both lateral ends of a light emitting stripe region 2 on a light emitting end face 3 of the device 1. In this case, the depth Lr and the position of each of the recesses 4 and 4 are decided so that the near field pattern of the laser beam has the same distribution as the light intensity distribution and the phase distribution obtained by inverse Fourier transformation of the far field pattern of the predetermined single lobe. Accordingly, the beam emitted from the end face 3 becomes substantially single lobe of the far field pattern by the recesses 4 and 4 to become the beam suitable for an optical communication equipment or an optical memory device.