Light from the scanner LED passes to the sensor through the following route:
1st Mirror > 2nd Mirror > 3rd Mirror > Lens Block > Sensor (SBU)
| No. | Descriptions | No. | Descriptions |
|---|---|---|---|
| 1 | Scanner Home Position Sensor | 7 | Lens Block |
| 2 | 2nd Mirror | 8 | SBU |
| 3 | 3rd Mirror | 9 | Scanner Drive Motor |
| 4 | 1st Scanner Carriage | 10 | 1st Mirror |
| 5 | Scanner LED | 11 | 2nd Scanner Carriage |
| 6 | Original Length Sensor | 12 | Anti-Condensation Heater (optional) |