41
Ricoh Co. Ltd.
http://www.ricoh.com/
B245-62 / PD-C4
Slide 41
Video Control Unit (VCU)
Fine Character and Image (FCI)
The FCI performs image smoothing.
This functions only affects binary
picture processed images for certain
original modes.
Usually, binary picture processing
generates jagged edges on
characters, as shown in the
illustration. These are reduced using
edge smoothing. The FCI changes
the laser pulse duration and position
for certain pixels.
Fig. A shows the four possible pulse
durations, and Fig. B shows how the
laser pulse can be in one of three
positions within the pixel. Fig. C
shows an example of how edge
smoothing is used.
(Continued in notes.)
Main Scan
Sub
Scan
FCI smoothing is only effective when Text 2 or Special 1 is selected. There is no SP
adjustment for this.
Printer Gamma Correction
Printer correction corrects the data output from the IPU to the laser diode to account for
the characteristics of the engine components (e.g. drum, laser diode, lenses).
The machine chooses the most suitable gamma curve for the original type selected by
the user. There is no SP adjustment for this.
