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US 6,724,949 B1Granted
Image reading apparatus and image reading method
AssigneeFuji Photo Film Co., Ltd.
InventorYoshirou Yamazaki
Life of this patent
Estimating the term…
Abstract
An image reading device is provided which can read an image at a wide dynamic range and which can be constructed at low cost. Film images which are recorded on a photographic film undergo a preliminary reading by an area CCD. On the basis of the image data obtained from the reading, the density of each LCD cell of an LCD when performing the main scanning of the image can be calculated so that the amount of incident light on the area CCD is as great as possible without saturation of the accumulated charge in each photoelectric conversion cell occurring. The film image then undergoes the main reading with the density of each LCD cell of the LCD controlled so as to be the above calculated density.
Claims16
An image reading apparatus comprising:
- a reading apparatus for separating an image to be read into a plurality of pixels and reading the image as signals by photoelectrically converting incident light from each pixel of the image;
- determination device for determining suitable reading conditions for each pixel or for each of small areas comprising a plurality of the pixels, based on signals read by the reading apparatus;
- and
- a control apparatus for performing control so as to obtain signals identical to signals obtained when each pixel or each small area of the image is read under the reading conditions determined by the determination device;
- wherein the reading apparatus is able to change image reading conditions for each of the pixels and for each of the small areas, and wherein the control apparatus performs control such that the reading conditions determined by the determination device are set as the reading conditions for the reading apparatus, wherein the image reading apparatus further comprises a reading sensor for reading the image by photoelectrically converting incident light from the image for each pixel, and an incident light amount alteration apparatus capable of altering the amount of incident light on the reading sensor for each pixel or for each small area, wherein the control apparatus performs control such that the amount of incident light striking the reading sensor via the incident light amount alteration apparatus matches the reading conditions for each of the pixels or for each of the small areas.
2 more elements
An image reading apparatus comprising:
- a reading apparatus for separating an image to be read into a plurality of pixels and reading the image as signals by photoelectrically converting incident light from each pixel of the image;
- determination device for determining suitable reading conditions for each pixel or for each of small areas comprising a plurality of the pixels, based on signals read by the reading apparatus;
- and
- a control apparatus for performing control so as to obtain signals identical to signals obtained when each pixel or each small area of the image is read under the reading conditions determined by the determination device;
- wherein the reading apparatus is able to change image reading conditions for each of the pixels and for each of the small areas, and wherein the control apparatus performs control such that the reading conditions determined by the determination device are set as the reading conditions for the reading apparatus, wherein the reading apparatus includes a charge accumulation type reading sensor capable of altering a charge accumulation time for each of the pixels or small areas and reads an image as signals by photoelectrically converting incident light from the image for each pixel and accumulating the converted light as a charge, and wherein the control apparatus controls the reading conditions of the reading apparatus for each of the pixels or small areas by altering charge accumulation times of the reading sensor.
2 more elements
An image reading method comprising the following steps:
- (a) a step in which an image to be read is divided into a plurality of pixels and the image is read as signals by photoelectrically converting incident light from the image for each pixel;
- (b) a step in which suitable reading conditions are determined for each of the pixels or each of the small areas comprising a plurality of pixels based on signals read in step (a);
- and
- (c) a step in which control is performed using the reading conditions determined in step (b) such that signals equivalent to signals obtained if the image were read under the reading conditions for each of the pixels or small areas are obtained;
- wherein, in step (a), image reading conditions can be altered for each of the pixels or each of the small areas, and wherein, in step (c), the suitable reading conditions determined in step (b) are controlled so as to be set as the reading conditions for step (a), wherein step (a) includes a step in which the image is read by photoelectrically converting incident light from the image for each pixel using a reading sensor, and a step in which an amount of incident light on the reading sensor is altered by the incident light amount alteration apparatus for each of the pixels or small areas, and wherein, in step (c), an amount of incident light striking the reading sensor via the incident light amount alteration apparatus is controlled so as to match the reading conditions for each of the pixels or small areas.
2 more elements
An image reading apparatus comprising:
- a reading apparatus for separating an image to be read into a plurality of pixels and reading the image as signals by photoelectrically converting incident light from each pixel of the image;
- determination device for determining suitable reading conditions for each pixel or for each of small areas comprising a plurality of the pixels, based on signals read by the reading apparatus;
- and
- a control apparatus for performing control so as to obtain signals identical to signals obtained when each pixel or each small area of the image is read under the reading conditions determined by the determination device, wherein the image reading apparatus further comprises a reading sensor for reading the image by photoelectrically converting incident light from the image for each pixel, and an incident light amount alteration apparatus capable of altering an amount of incident light on the reading sensor for each pixel or for each small area, wherein the control apparatus performs control such that the amount of incident light striking the reading sensor via the incident light amount alteration apparatus matches the reading conditions for each of the pixels or for each of the small areas.
1 more element
An image reading apparatus comprising:
- a reading apparatus for separating an image to be read into a plurality of pixels and reading the image as signals by photoelectrically converting incident light from each pixel of the image;
- determination device for determining suitable reading conditions for each pixel or for each of small areas comprising a plurality of the pixels, based on signals read by the reading apparatus;
- and
- a control apparatus for performing control so as to obtain signals identical to signals obtained when each pixel or each small area of the image is read under the reading conditions determined by the determination device, wherein the reading apparatus includes a charge accumulation type reading sensor capable of altering a charge accumulation time for each of the pixels or small areas and reads an image as signals by photoelectrically converting incident light from the image for each pixel and accumulating the converted light as a charge, and wherein the control apparatus controls the reading conditions of the reading apparatus for each of the pixels or small areas by altering charge accumulation times of the reading sensor.
1 more element
An image reading apparatus comprising,
- a reading apparatus for separating an image to be read into a plurality of pixels and reading the image as signals by photoelectrically converting incident light from each pixel of the image;
- determination device for determining suitable reading conditions for each pixel or for each of small areas comprising a plurality of the pixels, based on signals read by the reading apparatus;
- and
- a control apparatus for performing control so as to obtain signals identical to signals obtained when each pixel or each small area of the image is read under the reading conditions determined by the determination device, wherein:
- the determination device determines suitable reading conditions for each pixel or for each of the small areas comprising a plurality of the pixels so that low frequency components are extracted, based on low frequency components of signals read by the reading apparatus;
- and
- the control apparatus performs control so as to obtain signals identical to signals obtained when each pixel or each small area of the image is read under the reading conditions determined by the determination device, and adds low frequency components so as to obtain signals identical to signals obtained when each pixel or each small area of the image is read with a high degree of accuracy at a high dynamic range.
4 more elements
Dependencies are inferred from the claim text.