| 摘要 |
PURPOSE:To allow the translucent resin to serve as a beam splitter and a package by defining a path of laser beam by the translucent resin having a cutoff. CONSTITUTION:All the components are sealed with translucent resin 29 except that outside projections 23c of leads 23b remain unsealed. In part of the sealing resin 29, a cutoff section 33 constituted of two planes, a first flat plane 30 and a second flat plane 31, is formed. The optical axis of the laser beam emitted by a laser diode 27 passes through the first plane 30 vertical to the optical axis and comes outside of the sealing resin 29 and then is reflected on the second plane 31 that is inclined at 45 deg. to the first plane 30, proceeding in the direction vertical to principal planes of a lead frame 23 and an Si substrate 24, and finally reaches a photodiode 25. By this method, expensive components such as a glass prism and a ceramic package are not necessary and of course no assembling of such components is required. Therefore, a small-size and light-weight optical module can be obtained. |
