| 摘要 |
PROBLEM TO BE SOLVED: To conduct efficient optical communication even with a small lens. SOLUTION: Lenses 3a, 4a, 5a of a light receiver side are arranged along a major axis of an isotropic light 2 emitted from a laser diode 1 at an optical transmitter side. The laser diode 1 is manufactured by stacking epitaxy layers on a substrate. Then a direction perpendicular to the film of the laser diode 1 receives the effect of diffraction and an emission angle is increased more than that of the horizontal direction. As a result, the laser diode emits a laser beam that is shaped to draw an ellipse whose major axis is present in the vertical direction. The laser diode 1 emits the light 2 without much shaping by its optical system to allow a receiving end to receive the light 2 in an elliptic shape. Then the lenses 3a, 4a, 5a arranged along the major axis of the ellipse receive the light 2. The effect of momentary interruption of the light or the like due to an obstacle can be suppressed by synthesizing the light made incident onto the lenses 3a, 4a, 5a. |
