| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a small and inexpensive laser diode module (LD) which realizes optical pickup with little spurious radiation. <P>SOLUTION: In the laser diode module, a light emitting/receiving unit including LD and a light receiving element and an LD protection component protecting LD from electric destruction are mounted on a multilayer substrate, and they are integrated as one module. A high frequency superposition circuit superimposing a high frequency current with LD, and an EMC countermeasure circuit reducing electromagnetic wave noise generated from the high frequency superposition circuit, can be integrated. A part of elements constituting the high frequency superposition circuit and the EMC countermeasure circuit are incorporated in the multilayer substrate. For making short a distance between a coil and a capacitor which are included in the EMC countermeasure circuit, the capacitor is disposed in the substrate which is positioned just below the coil mounted on the surface of the substrate. A connection pattern for a flexible printed board is installed, and the pattern is arranged on a face opposite to the mounting face of the light emitting/receiving unit. Control IC of the light emitting/receiving unit is mounted on the substrate and they can be integrated. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
