Image reading method and reader

Abstract

Provided is an image reading apparatus for properly carrying out a shading correction by eliminating the effect due to a dirt caused by dust or the like on a white reference part read by a fixed read means. The image reading apparatus 1 is provided with the white reference part 22 that is placed movably between a read position of a second CCD (charge coupled device) 21 and a standby position apart from the read position of the second CCD 21 while a side colored in white and providing shading data faces an opposed side to an original carrying path, and moves the white reference part 22 to the read position of the second CCD 21 to acquire data resulting from reading the white reference part 22 by the second CCD 21 as the shading data for shading correction. Thus, the image reading apparatus prevents the white reference part 22 from getting dirt due to paper powder of an original G and abraision chaff of rollers or the like adhering to the white reference part 22, acquires highly accurate shading data and can obtain a high quality reading image without stripes and unevenness.

Description

technical field [0001] The present invention relates to an image reading method and an image reading device, and more specifically, to a method capable of removing the influence of dirt such as dirt and dust on a white reference portion read by a fixed reading device, and appropriately performing shading correction (shading). correction) image reading method and image reading device. Background technique [0002] Recently, a double-sided reading image scanner for reading front and back images of a double-sided original at high speed and high quality has appeared. Generally, the double-sided reading image scanner is provided with a flatbed unit and an automatic Input (auto document feeder, hereinafter referred to as "ADF") component. The platform component is to set the image surface of the original on the platen glass, along the bottom of the platen glass, configure the first optical system that reciprocates in the sub-scanning direction, set the original on the platen glas...

AI Technical Summary

Problems solved by technology

[0012] However, even if the technology described in the above-mentioned Patent Document 2 is used, there is a lot of dust in the air, which will adhere to the white platen roller. If the white platen roller is baked, the color of the white platen roller will be changed, and the white platen roller will be deteriorated due to the gas generated by the lamp. Due to the above-mentioned reasons, when the second optical system reads the white platen roller, the density of the obtained data will be uneven, or the white platen table roller dirty

[0013] Therefore, if the data obtained when the above-mentioned white platen roller is read by the second optical system is used as shading data to perform shading correction, density unevenness or streaks will also occur in the read image, and there is a problem that the image quality will deteriorate.

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