JPH0433050U - - Google Patents

Description

[Brief explanation of drawings]

Fig. 1 is a schematic diagram of the main parts of a digital copying machine showing an embodiment of the present invention, Fig. 2 is an explanatory diagram showing image samples of originals in normal mode and black-and-white inversion mode, and Fig. 3 shows black and white parts. A graph showing the relationship between the developing electric field cost and white areas in the solid area, Figure 4 is image exposure,
FIG. 5, which is an image formation model diagram by reversal development, is a graph showing the relationship between the potential difference between the bright area potential and the developing bias and resolution. 1...Photosensitive drum, 3...Laser beam,
4...Developer, VD...Dark area potential, VL...Bright area potential, VB...Developing bias.

Claims (1)

[Scope of Utility Model Registration Claim] An image forming device that reads image information from a document, converts it into a digital signal, and then forms an electrostatic latent image on a photoreceptor through image exposure using a laser, and converts it into a visible image using a developing device. In the image forming apparatus capable of selectively switching between optical writing in a normal mode and optical writing in a black-and-white inversion mode during the image exposure, the condition of the surface potential of the photoreceptor is set in the normal mode and the black-and-white inversion mode. The image forming apparatus described above is characterized in that the image forming apparatus performs development by changing the image forming apparatus.