Ricoh A293 Manuale di servizio - Pagina 3

Sfoglia online o scarica il pdf Manuale di servizio per Stampante All in One Ricoh A293. Ricoh A293 18.

Rev. 10/2002
2.2 SCANNING..............................................................................................2-13
2.2.1 OVERVIEW ....................................................................................2-13
2.2.2 SCANNER DRIVE ..........................................................................2-14
2.2.3 ORIGINAL SIZE DETECTION IN BOOK MODE ............................2-15
2.3 IMAGE PROCESSING ............................................................................2-16
2.3.1 OVERVIEW ....................................................................................2-16
2.3.2 SBU ................................................................................................2-17
2.3.3 AUTO IMAGE DENSITY (ADS) ......................................................2-18
2.3.4 IPU (IMAGE PROCESSING UNIT).................................................2-19
Overview.............................................................................................2-19
2.3.5 IMAGE PROCESSING STEPS AND RELATED SP MODES.........2-20
2.3.6 AUTO SHADING ............................................................................2-25
Black Level Correction ........................................................................2-25
White Level Correction........................................................................2-25
2.3.7 BACKGROUND ERASE.................................................................2-26
Background Erase ..............................................................................2-26
2.3.13 INDEPENDENT DOT ERASE ......................................................2-27
2.3.9 FILTERING, MAIN SCAN MAGNIFICATION/REDUCTION ...........2-28
Overview.............................................................................................2-28
Filtering ...............................................................................................2-28
Main Scan Magnification/Reduction....................................................2-29
Sub Scan Magnification ......................................................................2-29
2.3.10 GAMMA (G) CORRECTION.........................................................2-30
2.3.11 GRADATION PROCESSING .......................................................2-30
Three-graduation Processing..............................................................2-30
Four-graduation Processing................................................................2-31
Error Diffusion and Dithering...............................................................2-31
2.3.12 LINE WIDTH CORRECTION........................................................2-31
2.4 LASER EXPOSURE................................................................................2-32
2.4.1 AUTO POWER CONTROL.............................................................2-32
2.4.2 DUAL BEAM WRITING ..................................................................2-33
2.4.3 LASER BEAM PITCH CHANGE MECHANISM
(FOR A292/A293 ONLY) .................................................................2-34
2.4.4 LD SAFETY SWITCHES ................................................................2-35
2.5 DRUM UNIT ............................................................................................2-36
2.5.1 PROCESS CONTROL....................................................................2-36
Overview.............................................................................................2-36
Drum potential sensor calibration .......................................................2-37
VSG adjustment..................................................................................2-37
VG Adjustment....................................................................................2-38
LD power adjustment ..........................................................................2-39
Toner Density Adjustment...................................................................2-39
VREF Update......................................................................................2-40
2.5.2 DRUM UNIT COMPONENTS.........................................................2-41
2.5.3 DRUM CHARGE.............................................................................2-42
Overview.............................................................................................2-42
Charge Corona Wire Cleaning Mechanism.........................................2-43
2.5.4 DRUM CLEANING AND TONER RECYCLING..............................2-44
Overview.............................................................................................2-44
A292/A293/B098
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