Toshiba e-STUDIO4500c Service Manual page 31

6.5.5 DUST DETECTION ........................................................................6-36
Overview .............................................................................................6-36
What Happens if Dust is Detected? ....................................................6-37
How is the Dust Detected?..................................................................6-38
The Effects of SP Mode Settings on Dust Detection...........................6-39
6.6 IMAGE PROCESSING ............................................................................6-40
6.6.1 OVERVIEW ....................................................................................6-40
6.6.2 SBU (SENSOR BOARD UNIT).......................................................6-41
SBU.....................................................................................................6-41
Operation Summary ............................................................................6-41
Storing Operation Settings ..................................................................6-41
SBU Test Mode...................................................................................6-41
6.6.3 IPU (IMAGE PROCESSING UNIT).................................................6-42
6.7 LASER UNIT............................................................................................6-43
6.7.1 OVERVIEW ....................................................................................6-43
6.7.2 LD UNIT..........................................................................................6-44
Dual Beam Writing ..............................................................................6-44
LD Safety Switches .............................................................................6-44
6.7.3 OPTICAL PATHS............................................................................6-45
Optical Path ........................................................................................6-46
6.7.4 IMAGE POSITION CORRECTION (MUSIC) ..................................6-47
What does MUSIC do? .......................................................................6-47
When is MUSIC done?........................................................................6-47
Location of the MUSIC Sensors ..........................................................6-48
How is MUSIC Done? .........................................................................6-49
3rd Mirror Position Adjustment............................................................6-51
Exposure Unit Temperature Sensors ..................................................6-51
6.8 PHOTOCONDUCTOR UNITS (PCU) ......................................................6-52
6.8.1 OVERVIEW OF TANDEM PCU UNITS ..........................................6-52
6.8.2 AROUND THE DRUM ....................................................................6-53
Drum Drive ..........................................................................................6-54
Drum Charge ......................................................................................6-55
Drum Cleaning ....................................................................................6-56
Drum Ventilation..................................................................................6-57
Ozone Ventilation................................................................................6-59
6.8.3 DEVELOPMENT UNIT ...................................................................6-60
Overview .............................................................................................6-60
Development Unit Operation...............................................................6-61
Development, PCU Drive ....................................................................6-62
6.9 TONER SUPPLY .....................................................................................6-63
6.9.1 OVERVIEW ....................................................................................6-63
6.9.2 TONER SUPPLY MECHANISM .....................................................6-65
6.9.3 TONER CARTRIDGE .....................................................................6-66
6.9.4 TONER END SENSORS ................................................................6-68
Toner near-end ...................................................................................6-68
Toner end............................................................................................6-69
Toner End Recovery ...........................................................................6-69
6.10 WASTE TONER COLLECTION.............................................................6-70
6.10.1 WASTE TONER PATH .................................................................6-70
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