| 摘要 |
PROBLEM TO BE SOLVED: To provide a sheet detecting device, and a sheet carrying device and an image forming device provided with the sheet detecting device capable of reducing noise light detected by a light receiving element through an inside of a printed circuit board, enhancing a S/N ratio, and stably detecting a sheet constantly. SOLUTION: The sheet detecting device, provided with a light emitting and receiving unit which mounts a light emitting element and a light receiving element on a same printed circuit board 32, includes a solid black silk print layer 5 for preventing reflection of detection light, and a solid GND pattern layer 7 for preventing the detection light from entering glass-cloth epoxy resin 8 formed in this order between a surface on an element mounting side of the printed circuit board 32 and the glass-cloth epoxy resin (a base material) 8. |
