Imaging device

Abstract

A printer prints a black mark BM having a left mark edge BMa and a right mark edge BMb on a paper P. An encoder offset SH_L_EDG for the left mark edge BMa is set based on the difference between the carriage position (encoder value PR_ENC_L) that is detected when the print head 10 prints the left mark edge BMa and the carriage position (encoder value SEN_ENC_L) that is detected when the media sensor 68 detects the left mark edge BMa. Similarly, an encoder offset SH_R_EDG for the right mark edge BMb is set based on the difference between the carriage position (encoder value PR_ENC_R) that is detected when the print head 10 prints the right mark edge BMb and the carriage position (encoder value SEN_ENC_R) that is detected when the media sensor 68 detects the right mark edge BMb. In this way, the printer can suppress the effects of mounting error and can prevent a decline in accuracy when detecting edges of the paper P.

Description

technical field [0001] The present invention relates to an image forming apparatus for forming an image on a recording medium. Background technique [0002] Image forming apparatuses for printing text, images, and the like on recording media such as paper are known in the art. This imaging device uses an optical sensor to detect the edge of the paper, and uses the edge of the paper as a reference position to control the movement of the print head mounted on the carriage as a whole, while spraying ink droplets on the desired position on the paper. [0003] The side edge of the recording medium can be detected by causing the optical sensor provided on the carriage to scan the medium in the width direction (left-right direction) of the medium while detecting the reflection value. Such a device has been proposed in Japanese Unexamined Patent Application Publication No. HEI-3-7371. In other words, in the detection, the position where the reflectance value increases for the firs...

AI Technical Summary

Problems solved by technology

[0005] However, the distance between the optical sensor and the bracket may differ from the design value due to installation errors, etc.

This installation error reduces the accuracy of detecting the edge of the recording paper

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