Abstract: An image acquisition apparatus comprising pixels each including sub-pixels, the apparatus comprising signal holding units for holding signals from the sub-pixels, and a signal processing unit for acquiring and processing each of the signals from the signal holding units, wherein the signal processing unit includes a first mode of amplifying, by a predetermined amplification factor, the signals held by the signal holding units and individually outputting the signals, and a second mode of amplifying, by amplification factors at least some of which are different from the amplification factor in the first mode, the signals held by the signal holding units to add and output the signals.

Abstract: An image reading apparatus comprises a first reading unit configured to output an analog signal by reading an original, a second reading unit different from the first reading unit, a conversion unit configured to convert analog signals outputted from the first reading unit and the second reading unit to digital signals, a wire connection control unit configured to control wire connection between the first reading unit and the second reading unit, and the conversion unit, and an output control unit configured to control an output of an analog signal from the first reading unit.

Abstract: An image reading apparatus comprises a first reading unit configured to output an analog signal by reading an original, a second reading unit different from the first reading unit, a conversion unit configured to convert analog signals outputted from the first reading unit and the second reading unit to digital signals, a wire connection control unit configured to control wire connection between the first reading unit and the second reading unit, and the conversion unit, and an output control unit configured to control an output of an analog signal from the first reading unit.

Abstract: A reading apparatus includes a reader that obtains image data by reading a reading target, a platen on which a document to be read by the reader located at a first position is set, a first member read by the reader located at the first position if there is no document on the platen, a second member read by the reader located at a second position, which is different from the first position, and a determination unit that performs a determination process for determining whether the document is set on the platen on the basis of a first output, which is obtained if the reader located at the first position reads the reading target, and a second output, which is obtained if the reader located at the second position reads the reading target.

Abstract: A reading apparatus includes a reader that obtains image data by reading a reading target, a platen on which a document to be read by the reader located at a first position is set, a first member read by the reader located at the first position if there is no document on the platen, a second member read by the reader located at a second position, which is different from the first position, and a determination unit that performs a determination process for determining whether the document is set on the platen on the basis of a first output, which is obtained if the reader located at the first position reads the reading target, and a second output, which is obtained if the reader located at the second position reads the reading target.

Abstract: According to an embodiment of this invention, opening/closing of an ADF unit is correctly detected even under the influence of outside light. More specifically, a light source provided in a reading unit is turned on to irradiate a white board, and first data based on reflected light from the white board is obtained. Next, the light source provided in the reading unit is turned off, and second data based on reflected light from the white board is obtained. The difference between the first data and second data is compared with a predetermined threshold. It is determined based on the comparison whether the ADF unit is in an opened or closed state.

Abstract: According to an embodiment of this invention, opening/closing of an ADF unit is correctly detected even under the influence of outside light. More specifically, a light source provided in a reading unit is turned on to irradiate a white board, and first data based on reflected light from the white board is obtained. Next, the light source provided in the reading unit is turned off, and second data based on reflected light from the white board is obtained. The difference between the first data and second data is compared with a predetermined threshold. It is determined based on the comparison whether the ADF unit is in an opened or closed state.

Abstract: There is provided an image reading apparatus that can read a plurality of images without troublesome operations by a user, in which a small-size light source with a small electric power consumption is used as an illumination light source used for reading an image of a transparent original. A surface illumination light source having a size large enough to illuminate one image among a plurality of images included in a transparent original is moved sequentially to positions at which the illumination light source can illuminate the respective images. Each image is read while the illumination light source is kept stationary at the position of the image. In addition, at the position of each image, the transparent original is pressed against an original table of the image reading apparatus.

Abstract: A reading apparatus comprising a plate on which a transparent original is placed, and a guide unit for setting the transparent original at a predetermined position on the original plate. A light source unit is settable at plural positions in contact with the guide unit for illuminating the transparent original which is urged against the original plate by the light source unit. A portion of the light source unit which is contacted with the transparent original is chamfered (R-worked) not to damage the transparent original. Further, a portion of the light source unit which is contacted with the transparent original is designed to urge the transparent original at an out of an image area of the original.

Abstract: This invention provides a technique which allows more faithful color reproduction by a relative simple arrangement. To this end, according to this invention, by time-divisionally driving R, G, B, and E LEDs respectively having dominant emission wavelengths of 630 nm, 525 nm, 470 nm, and 500 nm, a common monochrome line image sensor (102) scans a document image. Scanned image data of respective color components undergo correction equivalent to that attained by shifting the barycentric positions of respective wavelength distributions so as to become closer to the CIE-RGB sensitivity distributions.

Abstract: A histogram of density difference between each pixel and an adjacent pixel is prepared from the image data obtained by pre-scanning an original. Then an approximation function for the density difference histogram is generated, and the kind of the original is discriminated as text/photograph/other based on the coefficient of the approximation function. According to the kind of the original, a density conversion table matching each kind is prepared, and is used for density correction of the image obtained by main scanning. For a text original, the density conversion table is prepared from the distribution of data close to the light and dark ends of the density histogram. For a photograph original, the density conversion table is prepared from the coefficient of the approximation function for the cumulative histogram of the density histogram.

Abstract: A histogram of density difference between each pixel and an adjacent pixel is prepared from the image data obtained by pre-scanning an original. Then an approximation function for the density difference histogram is generated, and the kind of the original is discriminated as text/photograph/other based on the coefficient of the approximation function. According to the kind of the original, a density conversion table matching each kind is prepared, and is used for density correction of the image obtained by main scanning. For a text original, the density conversion table is prepared from the distribution of data close to the light and dark ends of the density histogram. For a photograph original, the density conversion table is prepared from the coefficient of the approximation function for the cumulative histogram of the density histogram.

Abstract: A histogram of density difference between each pixel and an adjacent pixel is prepared from the image data obtained by pre-scanning an original. Then an approximation function for the density difference histogram is generated, and the kind of the original is discriminated as text/photograph/other based on the coefficient of the approximation function. According to the kind of the original, a density conversion table matching each kind is prepared, and is used for density correction of the image obtained by main scanning. For a text original, the density conversion table is prepared from the distribution of data close to the light and dark ends of the density histogram. For a photograph original, the density conversion table is prepared from the coefficient of the approximation function for the cumulative histogram of the density histogram.

Abstract: An image processing apparatus capable of acquiring a high resolution image without a reduction in sensitivity includes a plurality of sensor chips connected to one another, each sensor chip including a first pixel row and a second pixel row, which are formed on the same semiconductor chip. The first pixel row has a plurality of pixels arranged in the main scanning direction, and the second pixel row has a plurality of pixels shifted along the main scanning direction with respect to the first pixel row.

Abstract: There is provided an image reading apparatus that can read a plurality of images without troublesome operations by a user, in which a small-size light source with a small electric power consumption is used as an illumination light source used for reading an image of a transparent original. A surface illumination light source having a size large enough to illuminate one image among a plurality of images included in a transparent original is moved sequentially to positions at which the illumination light source can illuminate the respective images. Each image is read while the illumination light source is kept stationary at the position of the image. In addition, at the position of each image, the transparent original is pressed against an original table of the image reading apparatus.

Abstract: This invention provides a technique which allows more faithful color reproduction by a relative simple arrangement. To this end, according to this invention, by time-divisionally driving R, G, B, and E LEDs respectively having dominant emission wavelengths of 630 nm, 525 nm, 470 nm, and 500 nm, a common monochrome line image sensor (102) scans a document image. Scanned image data of respective color components undergo correction equivalent to that attained by shifting the barycentric positions of respective wavelength distributions so as to become closer to the CIE-RGB sensitivity distributions.

Abstract: In a transparent original reading apparatus comprising a transparent original plate on which a transparent original and a transparent original guide unit are installed, a transparent original guide unit for setting the transparent original at a predetermined position on the original plate, a light source unit settable at plural positions in contact with the transparent original guide unit and having a surface light source for illuminating the transparent original, and an image reading unit for reading an image of the transparent original through the original plate, the transparent original is urged against the original plate by the light source unit. In order to prevent the scratching of the transparent original caused by a sliding movement of the light source unit on the original plate, the light source unit and the transparent original are positioned by the transparent original guide unit.

Abstract: In an image reading apparatus, required capacity of a memory for storing shading correction data is reduced, as well as the width of a standard white board for generating the shading correction data is shortened. These are achieved by sequentially generating the shading correction data corresponding to respective R, G and B components, independently, to share a data storage area necessary for generating shading correction data, further, by reversing a scanning direction when scanning a standard white board while illuminating it with light of the respective color components on generating the shading correction data.

Abstract: An image reading apparatus capable of switching between and reading a reflective original and a transparent original is adapted to consume less power and is reduced in size. The evolution of heat by a light source can be suppressed and power consumption reduced by using a solid-state light source such as an LED as light sources for illuminating both reflective and transparent originals. In addition, owing to use of LEDs and sharing of a timing drive circuit, the apparatus per se can be reduced in size.

Abstract: A histogram of density difference between each pixel and an adjacent pixel is prepared from the image data obtained by pre-scanning an original. Then an approximation function for the density difference histogram is generated, and the kind of the original is discriminated as text/photograph/other based on the coefficient of the approximation function. According to the kind of the original, a density conversion table matching each kind is prepared, and is used for density correction of the image obtained by main scanning. For a text original, the density conversion table is prepared from the distribution of data close to the light and dark ends of the density histogram. For a photograph original, the density conversion table is prepared from the coefficient of the approximation function for the cumulative histogram of the density histogram.