| 摘要 |
PURPOSE:To obtain high reliability by a method wherein a wavelength discrimination element made of the series reverse-connection of two photodiodes is made integral with a signal processing circuit. CONSTITUTION:The wavelength discrimination element is constructed by reversely connecting two photodiodes PD1 and PD2 in series. The photodiode PD1 consists of a P<+> type layer 15 and an N type layer 13, and the photodiode PD2 consists of a P type substrate 11 and the layer 13. When light is absorbed to a point B, the distribution of photocurrent to PD1 and PD2 becomes reversely proportional to the distance to the P<+> type layers 14 and 15. The transistor of a bipolar IC part consitutes the signal processing circuit by the formation of an N<+> type layer 17, an N type epitaxial layer 13, and N<+> type regions 18 and 19. |
