This machine performs PASCAL control (image characteristics correction control) on the printer side only to realize ideal image characteristics by using the two

color sensors mounted in the duplexing feeding unit, without using the reader unit.

This control is performed in the main controller on the printer side.

The printer outputs the test patterns based on the data in the main controller.

The color sensor sequentially reads the output test patterns and the main controller performs gradation correction to obtain ideal image characteristics.

DC-CON

MN-CON

[1]

[2]

[3]

[7]

[6]

[5]

[4]

[8]

[9]

F-7-43

[1] Color sensor driver PCB

[2] Color sensor PCB

[3] ROM PCB

[4] Paper

[5] Toner image

[6] Photo unit

[7] LED

[8] Color sensor solenoid

[9] Color sensor roller

NM-CON: main controller

DC-CON: DC controller

The machine transports the test pattern to the reverse vertical path unit at a constant speed (105g/m2 or less), and transports it from the reverse vertical path unit to

the duplexing feeding unit at 1/3 speed.

When the duplexing left sensor (PS19) in the duplexing feeding unit detects the paper, the machine turns on the color sensor and moves up the color sensor roller.

When the duplexing left sensor (PS19) detects the paper, LED lights up after a specified period of time and the test pattern is read.

1. Operation Flow

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