Patent ID: 8960835
Filing Date: 2015-02-24
Classification: B41J,H04N

Abstract:
1. An image forming apparatus that reads a test pattern which includes a line and is formed on a record medium and adjusts a discharge timing of a droplet, the image forming apparatus comprising: a reading unit that includes a print data storing unit configured to store print data of a uniform pattern which has a color different from a color of the test pattern and is to be provided in an area including the test pattern; a pattern forming unit configured to print the test pattern and the uniform pattern so that the test pattern contacts the uniform pattern on the record medium; a relatively moving unit configured to cause the record medium or the reading unit to move relative to the reading unit or the record medium; a first detection data obtaining unit configured to obtain first detection data received as the reflection light by the light receiving element while the light moves and impinges on the test pattern; a position detecting unit configured to perform a calculation for determining a position of the line in order to detect a position of the test pattern; a second detection data obtaining unit configured to obtain second detection data received as the reflection light by the light receiving element while the light moves and impinges on the record medium after the uniform pattern contacting the test pattern is formed and before the test pattern is formed; a subtracting unit configured to subtract a value substantially the same as a local minimum value of the first detection data from the first detection data and from the second detection data in order to obtain subtracted first detection data and subtracted second detection data; and a signal correcting unit configured to calculate a ratio between the first subtracted detection data and the second subtracted detection data in order to align local maximum values of the first detection data so as to be substantially constant.