| 摘要 |
<p>PROBLEM TO BE SOLVED: To manage laser beam deviation.SOLUTION: An image formation device comprises: an image carrier on which an image is formed with a light beam; a scan part which scans the light beam reflected with a rotary polygon mirror in a second direction while driving the image carrier in a first direction to irradiate the image carrier with the light beam; a transfer part which transfers the image on the image carrier to a sheet; and a control part which controls light emission while controlling scanning, generates an image of a j-th adjustment pattern which repeats the presence and absence of light emission in the second direction with a j-th reflection surface of the rotary polygon mirror and an image of a k-th adjustment pattern which repeats the presence and absence of light emission in the second direction with a k-th reflection surface of the rotary polygon mirror at the same light emission timing in the second direction, obtains the characteristic curve of a light receiving signal level, the light receiving element pitch of a reading part, the number of light receiving elements of the reading part corresponding to one period of the characteristic curve, the number of repetition of the adjustment pattern corresponding to one period of the characteristic curve, the number of light receiving elements corresponding to the phase difference, and the phase difference between the characteristic curves of the j-th adjustment pattern and the k-th adjustment pattern obtained by reading the images of the j-th/k-th adjustment patterns, and calculates the positional deviation in the second direction of the images of the j-th/k-th adjustment patterns.</p> |
