Patent ID: 8107833
Filing Date: 2012-01-31
Classification: G03G

Abstract:
1. An image forming apparatus comprising: a temperature storage unit that stores therein a reference temperature value; a temperature detecting unit that detects a temperature within the image forming apparatus immediately after power is turned on; a determining unit that determines whether a difference between the reference temperature value and the temperature detected by the temperature detecting unit is equal to or larger than a first value, the temperature storage unit updating and storing the temperature detected by the temperature detecting unit as a new reference temperature value when the difference between the reference temperature value and the temperature detected by the temperature detecting unit is equal to or larger than the first value; a pattern forming unit that, when the determining unit determines that the difference is equal to or larger than the first value, forms a pattern for measurement including sub-patterns of a plurality of parallel color strips on a transfer medium; a position detecting unit that detects positions of the sub-patterns of each of the colors on the transfer medium; a calculating unit that calculates a misregistration-amount for each sub-pattern based on the position of the sub-pattern and a predetermined position for that sub-pattern; a correcting unit that corrects a position on which a sub-pattern is to be formed based on the misregistration-amount for that sub-pattern; and an image forming unit that forms an image for each color on the transfer medium using the position of a color corrected by the correcting unit, and superposes the image onto a recording medium, wherein the pattern forming unit is prevented from forming the pattern when the determining unit determines that the difference is smaller than a second value.