| 摘要 |
<p>PROBLEM TO BE SOLVED: To obtain an optical branching/coupling device which does not generate malfunction in signal transmission, causing a harmful influence to speeding-up by producing dullness of a signal waveform due to mode dispersion of signal light. SOLUTION: The device is composed of a first laser diode 10a to a fourth laser diode 10d, an optical transmission part 12, and a first photodiode 14a to a fourth photodiode 14d. A spreading angle 2r1 in the lateral direction and a spreading angle 2r2 in the longitudinal direction of signal light which are emitted from respective laser diodes, an angleαin the lateral direction and an angleβin the longitudinal direction of respective photodiodes with respect to the light-emitting part of respective laser diodes, a refractive index of the optical transmission part 12, an NA(numerical aperture), a critical angle (θc) and length n are decided to satisfy Equation (1), where c is the speed of light.</p> |
