An image acquiring device comprises: an automatic document feeder comprising: an input tray supporting an information medium; and a control panel comprising an operation button for selecting one image acquiring side of the information medium; an image acquiring assembly acquiring the image of the image acquiring side; a processor electrically connected to the automatic document feeder, the image acquiring assembly and the operation button; a storage, which is electrically connected to the processor and comprises an image module storing program codes for enabling acquiring the image of the image acquiring side; and an output unit receiving and outputting the image of the image acquiring side. The processor controls the image acquiring assembly to acquire the image of the image acquiring side according to the program codes and different signals of the operation button and transmits the image to the output unit. Associated copying method and system are also provided.

An object of the present invention is to detect the home position with a high accuracy without being affected by temperature. The present invention is an image reading apparatus having a reading portion, and the apparatus includes: an acquisition unit configured to acquire first data obtained by the reading portion reading a main scanning line in a state where a light source of the reading portion is turned on in a first light quantity, and second data obtained by the reading portion reading the main scanning line in a state where the light source of the reading portion is turned on in a second light quantity smaller than the first light quantity; a generation unit configured to generate difference data by subtracting the value of the second data from the value of the first data; and a determination unit configured to determine whether a mark arranged at a position corresponding to a home position of the reading portion has been detected on the main scanning line based on the difference data.

An optical member that refracts a light beam to diverge or focus the light beam, includes: at least three pairs of opposing surfaces. Each of the three pairs of opposing surfaces include a lens. Curvatures of the lenses at one side surfaces of the respective three pairs of surfaces are all the same, or curvatures of the lenses at one side surfaces of respective pairs of at least two pairs of the three pairs of surfaces are different from each other, and respective shortest distances between optical axes of the lenses at the one side surfaces of respective pairs of the at least two pairs of surfaces, and reference sides which are each any one of respective sides surrounding surfaces including the lenses are different from each other.

A read sensor generates front side image information indicating an image on a front side of an object to be read, and front side measurement information indicating a line of an image in a main scanning direction on the front side of a correction chart. A read sensor generates back side image information indicating an image on a back side of the object to be read, and back side measurement information indicating a line of an image in the main scanning direction on the back side of the correction chart. The image correction device calculates an amount of misalignment of read positions based on the front side measurement information and the back side measurement information, and corrects misalignment of images on the front side and the back side of the object to be read, indicated by the front side image information and the back side image information.

In an image-reading device, a counting unit counts a number of clock cycles of a spread-spectrum clock as a counter value. A correcting unit corrects one of the counter value and a reference clock cycle number based on a phase detected by the phase detecting unit when the counting unit counts. A comparing unit compares the counter value and the reference clock cycle number and determines whether the counter value and the reference clock cycle number satisfy a prescribed relationship. A time length setting unit sets a length of at least one of a reading time and an irradiation time based on: a timing when the counting unit starts counting to set the time length; and a timing when the comparing unit determines that the compared values satisfy the prescribed relationship, such that the time length set by the time length setting unit remains constant.

In an image-reading device, a counting unit counts a number of clock cycles of a spread-spectrum clock as a counter value. A correcting unit corrects one of the counter value and a reference clock cycle number based on a phase detected by the phase detecting unit when the counting unit counts. A comparing unit compares the counter value and the reference clock cycle number and determines whether the counter value and the reference clock cycle number satisfy a prescribed relationship. A time length setting unit sets a length of at least one of a reading time and an irradiation time based on: a timing when the counting unit starts counting to set the time length; and a timing when the comparing unit determines that the compared values satisfy the prescribed relationship, such that the time length set by the time length setting unit remains constant.

A medium conveying apparatus includes a plurality of feed rollers spaced in a direction perpendicular to a medium conveying direction, each of the feed rollers rotating independently at a respective speed to feed a medium, a plurality of brake rollers, each of the plurality of brake rollers being located to face a corresponding one of the plurality of feed rollers, a plurality of torque limiters separately provided between one of rotation shafts of the plurality of brake rollers and a corresponding one of the plurality of brake rollers, and a processor to detect a skew of the medium, and correct the skew of the medium by changing the speed of one of the plurality of feed rollers when the skew of the medium is detected.

A scanner includes: a first body having a window and a guide structure; a transparent platen connected to the first body to cover the window; a first sheet disposed on the transparent platen and in the window; a second sheet fixedly disposed on the transparent platen, in the window and on the guide structure, wherein the first sheet is thicker than the second sheet to form a cliff-sheet type guiding structure as a first part of a transporting passage; a scanning module disposed in the first body; a second body having a second part of the transporting passage; and a transporting mechanism being disposed in the second body and transporting a document along the transporting passage, so that the scanning module scans an image of the document through the window.

A scanner includes: a first body having a window and a guide structure; a transparent platen connected to the first body to cover the window; a first sheet disposed on the transparent platen and in the window; a second sheet fixedly disposed on the transparent platen, in the window and on the guide structure, wherein the first sheet is thicker than the second sheet to form a cliff-sheet type guiding structure as a first part of a transporting passage; a scanning module disposed in the first body; a second body having a second part of the transporting passage; and a transporting mechanism being disposed in the second body and transporting a document along the transporting passage, so that the scanning module scans an image of the document through the window.

An image reading apparatus includes a front-side reader, which includes a white LED configured to irradiate an original with light and a CMOS sensor configured to receive light that is reflected by the original. The front-side reader is configured to generate read data that represents a luminance value of an image on the original from the result of receiving light with the CMOS sensor. The image reading apparatus stores, in a non-volatile memory, a condition for determining whether there is a sub-scanning color shift, and uses a sub-scanning color shift detector to determine whether there is a sub-scanning color shift based on the read data obtained from the front-side reader and the condition stored in the non-volatile memory. When there is a sub-scanning color shift, the image reading apparatus corrects the sub-scanning color shift by correcting the read data with a color shift corrector.