| 摘要 |
<p>PURPOSE:To realize a transmissive optical coupler having high resolution and high transmission characteristics by arranging lighting windows such that they overlap each other with width narrower than that of each window while being shifted in the direction perpendicular to the optical axis from a light projecting window. CONSTITUTION:Light receiving element 13 having narrow light receiving element width W1 is employed and the elements 11, 13 are molded into primary molded bodies 12, 14 which are then placed oppositely to each other in a secondary mold 31 to be secondary molded. A light projecting window 17 and a lighting window 19 are formed by means of a protrusion 32 in the secondary mold 31 but since resolution is limited by the width dimension W0 thereof, the lighting window 19 is shifted in the direction perpendicular to the optical axis from the light projecting window 17 and arranged to overlap with width dimension of W2. When the widths W1, W2 are set appropriately in manufacturing stage, a transmissive optical coupler having high resolution and high transmission characteristics can be realized.</p> |
