HP 2500 Service Manual - Page 76
Latent image formation stage, Step 1: primary charging, Step 2: laser-beam exposure
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Latent image formation stage Step 1: primary charging A dc bias is applied to the primary charging roller, which transfers a uniform negative potential to the photosensitive drum. Figure 25. 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. Figure 26. Step 2: laser-beam exposure 74 Theory of operation C9706-90926
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74
Theory of operation
C9706-90926
Latent image formation stage
Step 1: primary charging
A dc bias is applied to the primary charging roller, which transfers a uniform negative potential to
the photosensitive drum.
Figure 25.
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.
Figure 26.
Step 2: laser-beam exposure