OVERVIEW 
SM 6-7 G104 
Detailed 
Descriptions 
 
1.  Drum charge: 
The charge roller gives the drum a negative charge 
2.  Laser exposure: 
The laser beam from the laser diode (LD) goes through the lens and mirrors 
and to the drum. To make a latent image on the drum, the machine turns the 
laser beam on and off.  
3.  Development: 
The development roller moves negatively-charged toner to the latent image 
on the drum surface. This machine uses four development units (one for 
each color). 
4.  Image transfer: 
The charge that is applied to the transfer roller pulls the toner from the drum 
to the transfer belt. Four toner images are put on the paper. 
5.  Cleaning for OPC drum: 
The cleaning brush and blade remove remaining toner on the drum surface 
after image transfer to the paper. 
6.  Quenching for OPC drum: 
Quenching is done at the end of each page with a quenching lamp (LED 
array) in the PCU.  
7.  Paper registration: 
The registration roller controls the paper feed timing to make sure that the 
image transfers to the correct location on the paper. It also removes skew. 
8.  Paper Transfer and Separation: 
Toner transfers from the transfer belt to the paper when the paper is fed 
between the transfer belt and transfer roller. At this time, the paper also 
separates from the transfer belt, because of a discharge plate immediately 
after the transfer roller. 
9.  ID sensor: 
The ID sensor board contains three ID sensors (one at the left, one at the 
center, and one at the right). The ID sensor detects the density of the ID 
sensor pattern on the transfer belt. The ID sensor output is used for process 
control and for automatic line-position adjustment, skew, and color 
registration adjustments for the latent image.