| US 7,499,660 B2 | ||
| Image forming apparatus and image forming method | ||
| Yuji Kamiya, Abiko (Japan) | ||
| Assigned to Canon Kabushiki Kaisha, Tokyo (Japan) | ||
| Filed on Oct. 23, 2007, as Appl. No. 11/877,267. | ||
| Application 11/877267 is a division of application No. 11/749884, filed on May 17, 2007, granted, now 7,336,910. | ||
| Application 11/749884 is a division of application No. 11/080490, filed on Mar. 16, 2005, granted, now 7,259,885. | ||
| Application 11/080490 is a division of application No. 09/797991, filed on Mar. 05, 2001, granted, now 6,987,576. | ||
| Claims priority of application No. 2000-060284 (JP), filed on Mar. 06, 2000; and application No. 2000-223726 (JP), filed on Jul. 25, 2000. | ||
| Prior Publication US 2008/0107432 A1, May 08, 2008 | ||
| Int. Cl. G03G 15/00 (2006.01) | ||
| U.S. Cl. 399—44 [399/55; 399/56; 358/1.9; 358/461; 358/519] | 5 Claims |
| 1. An image forming apparatus, which visualizes an image, according to a latent image potential, on an image bearing body,
which includes a charging unit and an exposing unit, in which a development potential is applied to a developing unit, and
a development contrast is a difference between the latent image potential and the development potential, wherein a designated
development contrast is defined as a sum of a basic development contrast Vcont, and a development correction amount ΔVcont1, for correcting the basic development contrast Vcont, said image forming apparatus comprising:
(a) a γ conversion unit having a γ conversion table γαi of a first value Vcontα of the designated development contrast in a case that the development contrast correction amount ΔVcont1 is a first value, and a γ conversion table γβi, different from the γ conversion table γαi, of a second value Vcontβ, different from the first value Vcontα, of the designated development contrast in a case that the
development contrast correction amount ΔVcont1 is a second value different from the first value of ΔVcont1; and
(b) an arithmetic operation unit for calculating a γ conversion table γNowi of a third value VcontNow of the designated development contrast in a case that the development contrast correction amount
ΔVcont1 is a third value, based on a formula:
γNowi=γαi+(γβi−γαi)×(Vcontα−VcontNow)/(Vcontα−Vcontβ),
wherein the subscript i is a value of an output density signal in the γ conversion table, and
wherein the γ conversion unit conducts γ conversion of the third value VcontNow of the designated development contrast, based
on the γ conversion table γNowi calculated by the arithmetic operation unit.
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