Toshiba E-STUDIO900 - Manual (Page 23)

B070/B071 1-10 PTM
3. LASER EXPOSURE
The processed data from the scanned original is retrieved from the hard disk
and transferred to the drum by four laser beams, which form an electrostatic
latent image on the drum surface. The amount of charge remaining as a latent
image on the drum depends on the laser beam intensity, which is controlled by
the laser diode board (LDB).
4. DRUM POTENTIAL SENSOR
The drum potential sensor detects the electric potential on the drum to correct
various process control elements.
5. DEVELOPMENT
The magnetic developer brush on the development rollers comes in contact
with the latent image on the drum surface. Toner particles are electrostatically
attracted to the areas of the drum surface where the laser reduced the negative
charge on the drum.
6. IMAGE TRANSFER
Paper is fed to the area between the drum surface and the transfer belt at the
proper time to align the copy paper and the developed image on the drum.
Then, the transfer bias roller and brush apply a high positive charge to the
reverse side of the paper through the transfer belt. This positive charge pulls
the toner particles from the drum to the paper. At the same time, the paper is
electrically attracted to the transfer belt.
7. PAPER SEPARATION
Paper separates from the drum as a result of the electrical attraction between
the paper and the transfer belt. The pick-off pawls also help separate the paper
from the drum.
8. ID SENSOR
The laser forms a sensor pattern on the drum surface. The ID sensor measures
the reflectivity of the pattern. The output signal is one of the factors used for
toner supply control.
9. CLEANING
The cleaning brush removes toner remaining on the drum after image transfer
and the cleaning blade scrapes off all remaining toner.
10. QUENCHING
The light from the quenching lamp electrically neutralizes the charge on the
drum surface.