HP color laserjet 2550 series Manuale Di Servizio
Step 1: primary charging
A dc bias is applied to the primary charging roller, which transfers a uniform negative
potential to the photosensitive drum.
potential to the photosensitive drum.
Figure 4-16.
Step 1: primary charging
Step 2: laser-beam exposure
The laser beam scans the photosensitive drum to neutralize negative charges on parts of
the drum. An electrostatic latent image is formed on the drum where negative charges were
neutralized.
the drum. An electrostatic latent image is formed on the drum where negative charges were
neutralized.
Figure 4-17.
Step 2: laser-beam exposure
Developing stage
The developing cylinder comes in contact with the photosensitive drum to deposit toner onto
the electrostatic latent image.
the electrostatic latent image.
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Chapter 4 Theory of operation
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