Panasonic DP-8032, Service Manual

Page: 227 / 397

227
DP-8032/8025
2008 Ver. 1.2
6.3. New Image Stabilizing Technology
To improve the copy quality, a new Toner Density Controller (QUANTUM II System) is developed.
The most important aim was to stabilize the Toner Density under various office environments.
Up to now, the control method was controlled by Laser Power and Grid Voltage. The new method is
controlled by Laser Pulse Duty with the Black and Gray Patterns for the Text and Text/Photo modes, and
the Check Pattern for Photo mode. As a result, it optimizes the solid black density, keeps the line width
consistent, and improves the halftone stability in photo mode.
The following illustrations show the New System.
1. Outline
2. Control System
Stable image density control for long period
Control method: Laser Power, Grid Voltage Control method : Laser Pulse Duty Control
QUANTUM Control Execute Timing:
1. After F8-09 (Toner Density Adj) and after F8-14 (Black Density Sensor Adjustment).
2. If QUANTUM Execute Flag* is enabled, when the Power Switch is ON or during Standby Mode.
*: QUANTUM Execute Flag is enabled after 8 hours have past since the previous QUANTUM
control.
3. After 200 sheets print in condition No.2, and after every 1,000 sheets are printed.
4. Manual start by General Function Mode > Manual Copy Quality Adjustment ....etc.
QUANTUM
White
Patch
Black Patch
LSU
Bias Voltage
Laser Power
Grid HVPS
Digital QUANTUM QUANTUM II
QUANTUM
II
LSU
Laser Pulse Duty
Control
Photo Mode Patch
Black Patch
Check Patch
Patch
Mark Patch
Mark
Digital QUANTUM
Black and white density is controlled to be stable
by Laser Power and Grid Voltage for long periods.
Difficult to control black solid density and line
width of the image at the same time.
QUANTUM II
Optimizes solid back density and keeps line
width consistent by Laser Pulse Duty Control.
Improves halftone stability in Photo Mode using
Photo Mode Patch.
Timer / Counter
OPC
Drum
Patch Pattern
Image Density Sensor
Check
LSU
Check Patch
Black Patch P Mode Gray
Laser Pulse Duty Control
Toner Density
Control
Toner Density Sensor
Toner Density Control
Temperature Sensor
Humidity Sensor
QUANTUM II
Control
QUANTUM II
Control
Photo Mode Gray
Black
Transfer
Control