| US 7,542,064 B2 | ||
| Image forming apparatus and method of controlling same | ||
| Tsuyoshi Moriyama, Ibaraki-ken (Japan); Katsumi Takahashi, Ibaraki-ken (Japan); Atsushi Chaki, Chiba-ken (Japan); and Takahiko Yamaoka, Chiba-ken (Japan) | ||
| Assigned to Canon Kabushiki Kaisha, Tokyo (Japan) | ||
| Filed on Feb. 10, 2006, as Appl. No. 11/350,775. | ||
| Claims priority of application No. 2005-054537 (JP), filed on Feb. 28, 2005. | ||
| Prior Publication US 2006/0192842 A1, Aug. 31, 2006 | ||
| Int. Cl. G06F 3/00 (2006.01); B41J 2/435 (2006.01); B41J 2/44 (2006.01) | ||
| U.S. Cl. 347—247 | 6 Claims |
| 1. An image forming apparatus comprising:
an image forming unit configured to form an image based upon a laser beam emitted from a semiconductor laser in accordance
with an image signal;
a driving unit configured to drive a current through the semiconductor laser;
a determination unit configured to determine whether a M×N pixel pattern included in the image formed by said image forming
unit has a pattern representing an intersection of plural lines or a pattern representing a part of the intersection; and
a control unit configured to control said driving unit to change over a current value of the current that flows through the
semiconductor laser in a period of a pixel to be controlled in the pattern, when the laser beam of the pixel to be controlled
is emitted, in a case where it is determined by said determination unit that the image has the pattern,
wherein said control unit controls to change over the current value of the current from a first current value to a second
current value which is less than the first current value in the period of the pixel, such that an amount of the laser beam
emitted from the semiconductor laser is changed over in the period of one pixel.
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