JP5381485B2 - Image reading device - Google Patents

Description

  The present invention relates to an image reading apparatus that irradiates a reading target with light from a light source, receives light emitted to the reading target with a light receiving circuit, and reads the reading target.

  2. Description of the Related Art Conventionally, an image reading apparatus that irradiates a document to be read from a light source and receives the light irradiated to the read object to read the read object is known to be incorporated in a facsimile machine or a copier. ing. There is also known a PC connection type image reading apparatus that reads a reading object in accordance with an instruction of a personal computer (PC) connected through a communication interface and transmits read image data representing the reading result to the PC.

Further, as this type of image reading apparatus, in addition to the image reading apparatus that conveys the reading unit in the sub-scanning direction and reads the reading target document placed on the document placing table, the reading unit is fixed and the reading target document is fixed. An image reading apparatus is known that reads a reading object by conveying the image in the sub-scanning direction. An image reading apparatus that conveys and reads a document to be read includes a plurality of reading units for reading the front and back surfaces of the document, and uses these reading units to read each of the front and back surfaces of the document. Is known (see, for example, Patent Document 1).
Furthermore, an image reading apparatus that performs pre-scanning and main scanning and changes the reading characteristics in main scanning after obtaining pre-scan image data is also known (see, for example, Patent Document 2).

  In addition, as a conventional apparatus, an image reading apparatus capable of reducing reading (see, for example, Patent Document 3) or a plurality of originals placed on an original placing table can be read and read image data corresponding to each original can be generated. An image reading apparatus (see, for example, Patent Document 4) is known. Specifically, as an image reading apparatus capable of reduced reading, an image that generates N times the read image data of N times by adding the accumulated charge in the light receiving element for N pixels at the time of reduced reading that is 1 / N times. Readers are known.

Japanese Patent Laying-Open No. 2005-072760 JP 2004007425 A Japanese Patent Laid-Open No. 11-308409 JP 2005-217509 A

  By the way, an image reading apparatus capable of reading a plurality of documents placed on a document placement table and generating read image data corresponding to each document is a relatively small one such as a photo or a business card (here, the original is a photo or a business card). Etc.)), and is useful for converting this into electronic data.

  However, the conventional apparatus has a drawback in that each of a plurality of documents placed on the document placing table cannot be read in different operation modes. For example, when a user puts a photo and a business card on the document table at the same time into electronic data, the reading resolution of the business card is set to a high resolution according to the photo even though low resolution reading is sufficient. It was necessary to set. In some cases, the processing time becomes unnecessarily long due to such a setting.

  On the other hand, in order to solve such a problem, if the image reading apparatus is configured so that the operation mode can be individually set for each original, the conventional technique moves the reading unit to the home position every time the operation mode is switched. Light quantity adjustment must be performed, and correction data for performing image correction such as shading correction must be generated. Therefore, a plurality of originals can be efficiently read in different operation modes and converted into electronic data. There was a problem that I could not do it.

  The present invention has been made in view of these problems, and is an image reading apparatus capable of reading a plurality of documents placed on a document placement table and generating read image data corresponding to each document. It is another object of the present invention to provide an image reading apparatus that can read each document in a different operation mode and that can efficiently read each original even when the operation modes are different.

  An image reading apparatus of the present invention made to achieve the above object irradiates light to a reading target from a light source, and receives the irradiation light passing through the reading target by a light receiving circuit arranged in the main scanning direction. A reading unit that generates line data composed of pixel data groups in the main scanning direction based on charges accumulated in each of the light receiving circuits, a conveying unit that can convey the reading unit in the sub-scanning direction, a reading unit, and a conveying unit The reading unit is scanned in the sub-scanning direction, and the reading unit reads each document to be read placed on the document placing table positioned in the scanning path in the main scanning direction. A reading control unit that obtains line data from the unit and generates read image data representing a reading result of the original composed of the line data group for each original placed on the original placing table. And, equipped with a.

  The image reading apparatus further includes a mode designation accepting unit that accepts designation of an operation mode at the time of reading for each document placed on the document placing table from a user for each document placed on the document placing table. The reading unit and the conveying unit are controlled so that the reading unit reads the white reference member at a position facing the white reference member, and each operation designated by the user through the mode designation receiving unit based on the reading result of the white reference member The mode includes reading characteristic setting means for setting the light amount to be output from the light source and the correction amount of the line data when reading the document in the operation mode as the document reading characteristic for each operation mode.

  In particular, the reading characteristic setting means of the present invention operates prior to the operation of the reading control means, and sets the original reading characteristics for “all operation modes” designated by the user for each operation mode. Then, after the operation of the reading characteristic setting unit, the reading control unit designates each of the documents placed on the document placing table by the user through the mode designation receiving unit in accordance with the document reading characteristic set by the reading characteristic setting unit. The reading unit is caused to read in the operation mode, and the generated line data is corrected to generate read image data representing the reading result of each original.

  According to the image reading apparatus of the present invention configured as described above, each time the operation mode is switched, the reading unit is returned to the position facing the white reference member, and the white reference member is read in the corresponding operation mode to read the document. Is not set, but the white reference member is read before the first original reading, and the original reading characteristics for all operation modes designated by the user are set.

  Therefore, according to the image reading apparatus of the present invention, it is not necessary to return the reading unit to the position facing the white reference member every time the operation mode is switched. That is, according to the image reading apparatus of the present invention, it is not necessary to carry out the conveyance control of the reading unit so as to return the reading unit to the position facing the white reference member every time the operation mode is switched. Accordingly, a plurality of documents placed on the document placing table can be read.

  As a result, according to the present invention, the image reading device that reads a plurality of documents placed on the document placing table and generates read image data corresponding to each document can read each document in different operation modes, Even when the operation modes are different, each original can be efficiently read.

By the way, the image reading apparatus in which the reading unit appropriately synthesizes (adds) the accumulated charges of the light receiving circuit according to the reading resolution to generate line data composed of pixel data groups in the main scanning direction corresponding to the reading resolution. in, as the operation mode at the time of reading of the original document placed on the document table, the designation of operation modes for reading resolution, to accept from the user for each document, Ru can configure the mode designation accepting means .

In addition, when the reading unit is controlled by the reading control unit and the color is selected as the operation mode related to the color, the light source for each color is sequentially irradiated to the reading target, and the reading target is irradiated for each color irradiated to the reading target. Light is sequentially received by the light receiving circuit, thereby generating line data composed of pixel data groups in the main scanning direction corresponding to the accumulated charges of the light receiving circuit sequentially for each color, generating color line data, and color When monochrome is selected as the operation mode, the light source of a specific color among the light sources for each color is irradiated to the reading target, and the light of the specific color irradiated to the reading target is received by the light receiving circuit, In an image reading apparatus that generates monochrome line data by generating line data corresponding to the charge accumulated in the light receiving circuit, an operation mode at the time of reading each document placed on the document placing table is set as the operation mode. The designation of the operation modes for the color to choices over and monochrome, to accept from the user for each document, Ru can configure the mode designation accepting means.

In addition, in the case of an image reading apparatus including a reading unit having both functions, the mode designation receiving unit selects color and monochrome as the operation mode at the time of reading each document placed on the document table. the specified operation mode defined by the combination of operating parameters relating to reading resolution and operating parameters on color, but it may also be the configuration for accepting from the user for each document.

  In this case, the reading control means operates in the operation mode (reading resolution, color / monochrome) designated by the user through the mode designation receiving means in accordance with the original reading characteristic set by the reading characteristic setting means after the operation of the reading characteristic setting means. The reading unit reads each document placed on the document placement table and corrects the generated line data to generate read image data having a reading resolution and color suitable for the operation parameters for each document. .

Further, the reading characteristic setting unit determines an operation mode used for light amount setting based on an operation mode for each original designated by the user through the mode designation receiving unit, and reads the white reference member in the reading unit in the determined operation mode. Based on this reading result, the appropriate light quantity is specified in the determined operation mode, and the appropriate light quantity in each operation mode designated by the user through the mode designation accepting unit with the specified light quantity as a reference. it is calculated, in accordance with the calculation results, Ru can be configured to set the amount of light output from the light source when reading a document in each mode.

According to the image reading apparatus configured as described above, it is not necessary to perform the light amount adjustment for the operation mode designated by the user, so that the light amount can be set quickly. As a result, according to the present invention, it is possible to shorten the processing time of a series of image reading including light amount adjustment, and to provide a user with a high-performance image reading apparatus in terms of processing speed. For example, in the case of an image reading apparatus capable of switching the reading resolution, the reading characteristic setting means has an operation mode or reading resolution having the lowest reading resolution among the operation modes for each original designated by the user through the mode designation receiving means. the reading resolution modes of operation to match the highest operation mode, Ru can be configured to determine the operating mode to be used for light quantity setting.

2A and 2B are a plan view and a cross-sectional view illustrating a configuration of the image reading apparatus 1, respectively. 2A is a block diagram illustrating an electrical configuration of the image reading apparatus 1, and FIG. 2B is a diagram illustrating an operation mode of the line sensor 31; FIG. FIG. 6 is a flowchart (a) showing a scanner operation acceptance process executed by the PC 65 and an explanatory diagram (b) showing a configuration of a mode setting screen displayed in the process. 5 is a flowchart of a reading control main process executed by a reading control unit 50. 6 is a flowchart of a main scan control process executed by a reading control unit. 6 is a flowchart illustrating a light amount adjustment process executed by a reading control unit. 6 is a flowchart illustrating a light amount calculation process executed by a reading control unit. It is a figure explaining the reading order of a document. It is the conceptual diagram (a) of correction data, and the figure (b) explaining the correction method of line data. 5 is a time chart showing control signals input to the line sensor 31.

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1A is a plan view illustrating a schematic configuration when the image reading apparatus 1 of the present embodiment is viewed from above, and FIG. 1B is a schematic cross-section along the sub-scanning direction of the image reading apparatus 1. FIG. However, in FIG. 1A, the main body cover 10 is shown in a transparent manner. As shown in FIG. 1, the image reading apparatus 1 according to the present embodiment includes an apparatus main body 20 and a main body cover 10 that can be opened and closed above the apparatus main body 20, and the main body cover 10 is closed. The upper surface of the apparatus main body 20 is configured as a so-called flat bed type scanner apparatus covered with the main body cover 10.

  The apparatus main body 20 includes a platen glass 21, a casing 25 that supports the platen glass 21, a cover material 27, a white reference member 29 provided on the back surface of the cover material 27, a line sensor 31, and a line sensor 31. , A belt conveyance mechanism 35, and a motor 37 for driving the belt conveyance mechanism 35.

  The casing 25 has a shape with an upper opening, and the platen glass 21 is fixed to the casing 25 so as to close the opening of the casing 25. In addition, the upper surface of the platen glass 21 extends in the main scanning direction along the left edge, which is the edge on the home position side of the line sensor 31, among the left and right edges of the platen glass 21 perpendicular to the sub-scanning direction. A long cover member 27 is attached so as to be in close contact with the upper surface of the platen glass 21 via a white reference member 29. In the following, a region exposed on the upper part of the apparatus main body 20 which is a surface region of the platen glass 21 and is not covered with the cover member 27 is particularly expressed as a “document placement table” 21 a. In the present embodiment, the document to be read is placed on the document placing table 21a.

  The white reference member 29 is formed of a white member having a length corresponding to the main scanning direction of the line sensor 31 and is provided at a position corresponding to the home position of the line sensor 31 so as to face the platen glass 21. It is fixed with a cover material 27.

  The line sensor 31 is provided in the lower region of the platen glass 21 so as to be able to advance and retract in the sub-scanning direction through the belt conveyance mechanism 35. The line sensor 31 includes a light receiving surface having a length approximately equal to the length of the platen glass 21 in the main scanning direction, and is configured as a well-known line sensor 31 that reads a document P placed on the platen glass 21 line by line. ing.

  Specifically, the line sensor 31 includes a light receiving element group 71 and light sources 73R, 73G, 73B (see FIG. 2) arranged in the main scanning direction, and irradiates the platen glass 21 with light from the light sources 73R, 73G, 73B. The reflected light of the light irradiated onto the reading target on the platen glass 21 is received by the light receiving element, so that the reading target is read in the main scanning direction, and the charge information of each pixel for one line in the main scanning direction is obtained as the reading result. Generate line data consisting of The line sensor 31 is provided in the housing 25 while being mounted on the carriage 33.

  The carriage 33 is fixed to a belt 35c wound around a pair of rollers 35a and 35b provided in the belt conveyance mechanism 35. The carriage 33 is acted on a belt 35c that is rotated by power generated by a motor 37, and moves in the sub-scanning direction. Moving. That is, the line sensor 31 is transported in the sub-scanning direction together with the carriage 33 transported by the belt transport mechanism 35. Hereinafter, a mechanism including the carriage 33, the belt conveyance mechanism 35, and the motor 37 is expressed as a “carriage conveyance mechanism” 40.

  Next, the electrical configuration of the image reading apparatus 1 will be described. FIG. 2A is a block diagram illustrating an electrical configuration of the image reading apparatus 1. As shown in FIG. 2A, the image reading apparatus 1 includes a reading control unit 50, a communication interface 60, and the above-described line sensor 31 and carriage conveyance mechanism 40 controlled by the reading control unit 50.

  The reading control unit 50 includes a CPU 51, a ROM 53, a RAM 55, and an A / D converter 57. The CPU 51 executes a process according to a program stored in the ROM 53, so that the motor 37 included in the line sensor 31 and the carriage transport mechanism 40 is provided. Control and realize functions necessary as an image reading apparatus. The A / D converter 57 is used to convert analog line data generated by the line sensor 31 into digital line data.

  The communication interface 60 is used to communicate with an external personal computer (PC) 65. The reading control unit 50 executes processing corresponding to a command received from the PC 65 through the communication interface 60, while providing read image data representing the reading result of the document to the PC 65 through the communication interface 60.

  For example, when receiving a pre-scan command or a main scan command from the PC 65, the reading control unit 50 drives the motor 37 to move the line sensor 31 in the sub-scanning direction and causes the line sensor 31 to perform a reading operation for each line. Then, line data is acquired from the line sensor 31, and based on this line data group, if the received command is a pre-scan command, pre-scan image data representing the reading result of the entire area of the document table 21a is generated. If the command is a main scan command, read image data representing the read result of the document is generated for each document placed on the document placement table 21 a and transmitted to the PC 65 through the communication interface 60.

  The line sensor 31 is a well-known line sensor capable of color reading, and includes light sources 73R, 73G, and 73B for red (R), green (G), and blue (B) colors, and light sources 73R and 73G. , 73B is provided with a light receiving element group 71 for receiving reflected light of the light irradiated to the platen glass 21 in the main scanning direction, and further for transferring charge information accumulated in the light receiving element group 71. A circuit 75 is provided.

  Specifically, the transfer circuit 75 includes an analog shift register, holds the charge accumulated in the light receiving element for each pixel by the analog shift register, and sequentially outputs the charge information as line data. Further, the light sources 73R, 73G, and 73B are configured in a line shape so that light can be applied to a region in the main scanning direction on the platen glass 21.

  In addition, the line sensor 31 is configured to be readable at a plurality of reading resolutions. In the line sensor 31, light receiving elements are arranged in the main scanning direction at a distance interval corresponding to the maximum reading resolution R_MAX. ing. Specifically, the line sensor 31 is configured to be capable of reading with a maximum reading resolution R_MAX in the main scanning direction and a reading resolution that is 1 / N of the maximum reading resolution R_MAX, and the maximum reading resolution R_MAX is When set, as shown in FIG. 2B, line data is generated by arranging the charge information accumulated in each light receiving element with each light receiving element as one pixel.

  On the other hand, when a reading resolution that is 1 / integer N of the maximum reading resolution R_MAX is set, as shown in FIG. 2C, the line sensor 31 has an N-th light receiving element arranged in the main scanning direction. The charge information representing the combined value of the accumulated charges of each group, where the accumulated charges of the N light receiving elements belonging to the same group are synthesized (added) by the transfer circuit 75 and each group is regarded as one pixel. Line data is generated by arranging. Note that FIG. 2B is an explanatory diagram showing a generation mode of line data when the maximum reading resolution R_MAX is set, and FIG. 2C is a setting of a reading resolution that is a half of the maximum reading resolution R_MAX. It is explanatory drawing showing the production | generation aspect of the line data in the case of being performed.

  The line sensor 31 generates line data of the number of pixels corresponding to the reading resolution by such a method, and inputs this to the reading control unit 50 through the transfer circuit 75. The read control unit 50 converts the analog line data output from the line sensor 31 into digital line data by the A / D converter 57, and then processes the software by the CPU 51. For example, the read image data Is transmitted to the PC 65.

  Next, before describing details of processing executed by the reading control unit 50, processing executed by the PC 65 that transmits various commands to the reading control unit 50 will be described. FIG. 3A is a flowchart showing a scanner operation reception process executed by the PC 65 when a reading start operation is performed by the user through the input device 67.

  When the scanner operation acceptance process is started, the PC 65 transmits a pre-scan command to the image reading apparatus 1 through the communication interface 60 (S110). When the prescan command is transmitted to the image reading device 1 in this way, the image reading device 1 reads the entire area of the document placing table 21a and transmits prescan image data representing the read result. In addition to the pre-scan image data, the image reading device 1 transmits position data of each document that appears in the pre-scan image represented by the pre-scan image data.

  When the PC 65 receives the pre-scan image data and the position data as response data from the image reading apparatus 1 after transmitting the pre-scan command (S120), the PC 65 displays the display device 69 (for example, a liquid crystal display) as shown in FIG. The mode setting screen A0 having the configuration shown is displayed, and the prescan image represented by the prescan image data received from the image reading device 1 is displayed in the preview display area A1 of the mode setting screen A0 (S130).

  FIG. 3B is a diagram illustrating the configuration of the mode setting screen A0. The mode setting screen A0 is configured as a graphical user interface (GUI) capable of selecting a plurality of documents shown in the pre-scan image in the preview display area A1 by operating a cursor. Further, on the left side of the preview display area A1 in the mode setting screen A0, there is a setting operation area A2 having an input object group for setting an operation mode at the time of the main scan for the document on which the cursor is placed in the preview display area A1. Is provided.

  That is, in S130, a pre-scan image is displayed in the preview display area A1, and based on the received position data of each original, an area of the pre-scan image in which the original located at the most upstream (home position side) in the sub-scanning direction is shown. The initial setting value of each parameter defining the operation mode is displayed in the setting operation area A2 as the operation mode to be applied to this document.

  More specifically, in the setting operation area A2, an input object B1 that can specify parameters related to colors that define the operation mode, an input object B2 that can specify parameters related to reading resolution that defines the operation mode, and a main scan start command are displayed in the image. An input object B3 for inputting to the reading device 1 is provided. Specifically, the input object B1 includes radio buttons that can select either “color” or “monochrome” as a color parameter, and the input object B2 is one of the reading resolutions that the line sensor 31 can handle. The input object B3 is composed of buttons that can be virtually pressed. In S130, the parameter initial setting values are displayed through the input objects B1 and B2 (see FIG. 3B).

  When the processing in S130 is completed, the PC 65 performs an operation of pressing the input object B3 (hereinafter referred to as “main scan start operation”) through the input device 67, or an operation other than the main scan start operation. It waits until a cursor operation in the preview display area or an operation on the input objects B1 and B2 is performed through the input device 67 (S140, S150).

  When an operation other than the scan start operation is performed (Yes in S150), the mode setting screen A0 displayed on the display device 69 is updated according to the operation content (S160). For example, when a cursor operation is performed, the cursor position is adjusted to the newly selected document in the preview display area, and the input objects B1 and B2 to be displayed in the setting operation area A2 are newly selected. Change to a state corresponding to the parameter value set for the document. In this way, in the setting operation area A2, the set value of the parameter currently set for the document corresponding to the cursor position is displayed.

  On the other hand, when an operation is performed on the input objects B1 and B2, the input objects B1 and B2 are changed to a state corresponding to the operation, and when the operation is an operation accompanied by a change of the parameter setting value, Temporarily stores changes to the parameter default settings. The temporarily stored data representing the changed contents is used to display the parameter setting values changed from the initial setting values through the input objects B1 and B2.

  When the processing in S160 is completed in this way, the PC 65 proceeds to S140 and waits until any of the above operations is performed through the input device 67. When the main scan start operation is performed through the input device 67 (Yes in S140), the main scan command is transmitted to the image reading apparatus 1 through the communication interface 60, and the parameter change contents on the mode setting screen A0 are reflected. The set values (latest values) of the parameters relating to the color and reading resolution that define the operation mode of each original document are transmitted to the image reading apparatus 1 (S170). In this case, for example, the setting values of the parameters relating to the color and the reading resolution are transmitted to the image reading apparatus 1 together with the corresponding document position data.

  When the main scan command or the like is transmitted in this manner, the image reading apparatus 1 reads each original in an operation mode corresponding to the parameter set on the mode setting screen, and reads image data representing the reading result of each original. Is transmitted from the image reading apparatus 1.

  Accordingly, the PC 65 receives the read image data for each document transmitted from the image reading apparatus 1 through the communication interface 60 after transmitting the main scan command and the like. Then, the received read image data of each original is stored in its own recording medium (hard disk device (HDD) or the like), and the display device 69 is controlled to display the read image represented by each read image data on the display device 69. It is displayed (S180). Thereafter, the scanner operation acceptance process is terminated.

  Subsequently, processing executed by the reading control unit 50 of the image reading apparatus 1 will be described. FIG. 4 is a flowchart showing a read control main process executed by the read control unit 50 when a pre-scan command is received from the PC 65 through the communication interface 60 (see FIG. 3: S110). When the reading control main process is started, the reading control unit 50 first executes a pre-scan process (S210). Specifically, the line sensor 31 and the motor 37 are controlled, and the line sensor 31 is transported in the sub-scanning direction from the home position so as to traverse the entire area of the document table 21a. The reading operation is executed, and line data for the entire area of the document table 21a is acquired from the line sensor 31. Then, prescan image data composed of a group of line data for all regions is generated (S210).

  When this process is finished, the reading control unit 50 controls the motor 37 to retract the line sensor 31 to the home position (S220). Further, the prescan image data is analyzed to detect the edge of each document displayed in the prescan image represented by the prescan image data, and each document placed on the document placement table 21a is placed on the document placement table 21a. The position is specified (S230). Then, as the response data, the pre-scan image data generated in S210 and the position data indicating the position of each document specified in S230 are transmitted to the PC 65 through the communication interface 60 (S240). When this process is finished, the reading control unit 50 waits until the main scan command is transmitted from the PC 65 by the process in the PC 65 (see FIG. 3: S170) (S250).

  Then, when the main scan command is received from the PC 65, the main scan of each document on the document table 21a, which has been specified by the processing in S230, according to the setting values of the color and reading resolution parameters for each document received together with the main scan command. The operation mode that is sometimes applied is determined as the operation mode determined by the parameter setting value received from the PC 65 (S260). Then, the main scan control process is executed according to the determined content (S270).

  FIG. 5 is a flowchart showing the main scan control process executed by the reading control unit 50. When the main scanning control process is started, the reading control unit 50, based on the content determined in S260, among the originals placed on the original placement table 21a and the originals whose operation mode is set to “color” and “monochrome” It is determined whether or not the document set to “” is mixed. Here, if the color-related parameters set for each document are unified in either “color” or “monochrome”, it is determined that they are not mixed, and if they are not unified, it is determined that they are mixed ( S310).

  If it is determined that they are mixed (Yes in S310), the parameter relating to the light amount adjustment color is set to “color” (S320), and if it is determined that they are not mixed (No in S310), the parameter relating to the light amount adjustment color is set. It is set to the same value as the operation mode set for each document (S325). Thereafter, the process proceeds to S330.

  In S330, the reading control unit 50 sets the parameter relating to the reading resolution for light amount adjustment to the lowest reading resolution among the reading resolutions set in S260 for each original to be scanned. In the present embodiment, in this way, the parameters relating to the color and reading resolution used for light amount adjustment are set, and the operation mode at the time of light amount adjustment is set.

  The reason why the minimum resolution is set here is that when the line sensor 31 is of the CIS type, a time for storing the charge Q for each pixel is required as the time required for the light amount adjustment. For example, when the minimum resolution is half of the maximum resolution, reading of the minimum resolution requires only two light receiving elements in parallel (see FIG. 2C), so that the charge accumulated in the two light receiving elements. (FIG. 2 (c): Q1 + Q2), the charge amount Q for one light receiving element at the highest resolution (FIG. 2 (b): Q1) may be obtained. That is, since the storage time in FIG. 2C may be a time for accumulating half of the charge as compared with the maximum resolution, the light amount adjustment value L0 is more suitable for light intensity adjustment at the lowest resolution than when executed at the highest resolution. The specific time is shortened. For this reason, in S330, the reading resolution at the time of light amount adjustment is set to the minimum resolution. In the present embodiment, as will be described later, the appropriate value of the light amount in each operation mode set in S260 is obtained by calculation based on the appropriate value L0 of the light amount obtained in the operation mode at the time of adjusting the light amount. In this embodiment, even if the light amount for each operation mode obtained in the above and the optimum value of the actual light amount may be slightly different due to variations in the light receiving element, etc., in this embodiment, correction is performed by shading correction (FIG. 9B). So no problem.

  After the processing of S330, the reading control unit 50 executes the light amount adjustment processing shown in FIG. 6A, so that the line sensor 31 operates in the operation mode corresponding to the set values of the parameters relating to the color and reading resolution for light amount adjustment. And an appropriate light amount L0 in this operation mode is specified (S340). FIG. 6A is a flowchart showing the light amount adjustment processing.

  When the light amount adjustment process is started, the reading control unit 50 determines whether or not the operation mode for adjusting the light amount (specifically, a parameter relating to the color for adjusting the light amount) is “color” (S510). If it is determined that the color is “color” (Yes in S510), the process proceeds to S520. If it is determined that the color is “monochrome” (No in S510), the process proceeds to S530.

  In S520, the reading control unit 50 sequentially turns on the light sources 73R, 73G, and 73B of the respective colors and causes the line sensor 31 to perform a reading operation at the reading resolution set in S330 while the light sources are turned on. Thus, the appropriate light amount value L0 when performing the main scan in the same operation mode as the operation mode for adjusting the light amount is specified. Specifically, the following processing is executed for each of the light sources 73R, 73G, and 73B, and an appropriate value L0 of the light amount of each color is obtained.

  That is, the line sensor 31 is caused to perform a reading operation while adjusting the amount of light output from the light source so as to decrease stepwise from a predetermined initial value. Obtained from the sensor 31. More specifically, for each adjusted light amount, the charge accumulated in the light receiving element is reset, the light receiving element starts to accumulate new charges, and the light source emits the light with the light amount. After that, the line data of the above-mentioned reading resolution representing the information of the charges accumulated in the light receiving element is acquired from the line sensor 31.

  During the reading operation, the line sensor 31 is disposed at the home position and is opposed to the white reference member 29. Accordingly, the line sensor 31 outputs line data representing the reading result of the white reference member 29 at the light amount and the reading resolution.

  Thereafter, the reading control unit 50 refers to each pixel value indicated by the line data that represents the reading result of the white reference member 29 and is converted into digital data for each of the adjusted light amounts, and the line data indicates The maximum value of the light amount that does not saturate all the pixel values (not the maximum value) is detected. Then, the detected light quantity is specified as an appropriate value L0 of the light quantity output from the corresponding light source. FIG. 6B is an explanatory diagram showing a method for specifying the appropriate value L0. For example, in the case of << 1 >> shown in FIG. 6B, the amount of light is too large and some pixel values are saturated. In this case, the amount of light is decreased and << 2> As shown by>, a light amount that does not saturate all pixel values is searched. In the light amount adjustment process, the light amount is adjusted in this way to obtain an appropriate light amount value L0.

  The reading control unit 50 performs such processing for each of the light sources 73R, 73G, and 73B, and obtains an appropriate value L0 of the light amount of each color when performing the main scan in the same operation mode as the operation mode for adjusting the light amount. That is, when the original is read in “color” and the original with the lowest reading resolution among the originals to be read is read, an appropriate light amount L0 is obtained for each color.

  On the other hand, when the process proceeds to S530, the reading control unit 50 performs the same process as the process in S520 only for the green light source 73G, and adjusts the amount of light while the white light is applied to the line sensor 31 with the reading resolution set in S330. The reference member 29 is read, and an appropriate value L0 of the amount of light output from the green light source 73G is specified based on the line data that is the read result.

  Incidentally, in this embodiment, when the original is read in “monochrome”, only the green light source 73G is turned on among the light sources 73R, 73G, and 73B. Accordingly, here, the appropriate value L0 of the light amount when the original is read in “monochrome” and the original with the lowest reading resolution among the originals to be read is obtained.

  In S520 and S530, when the reading control unit 50 sets the appropriate light amount value L0 in this way, the reading control unit 50 ends the light amount adjustment processing, and proceeds to S350. In S350, the reading control unit 50 selects an unprocessed operation mode as the processing target mode for the process of S360 from the operation modes set for each original in S260 (S350). A light amount calculation process for the target mode is executed (S360). FIG. 7 is a flowchart showing a light amount calculation process executed by the reading control unit 50.

  When the light amount calculation process is executed, the reading control unit 50 determines whether or not the light amount adjustment is executed in “color” (S710). The determination here is the same as in S510. If it is determined that the light amount adjustment is performed in “color” (Yes in S710), the process proceeds to S720. If it is determined that the light amount adjustment is performed in “monochrome” (No in S710), the process proceeds to S740.

  In S720, it is determined whether or not the processing target mode is “color”. That is, it is determined whether or not the parameter relating to the color defining the processing target mode is “color”. If it is determined that the color is “color” (Yes in S720), the process proceeds to S730, and if it is determined to be “monochrome” (No in S720), the process proceeds to S740.

  When the process proceeds to S730, the reading control unit 50 reads the original in the processing target mode for each of the red, green, and blue light sources 73R, 73G, and 73B based on the result of the light amount adjustment process executed previously. Sometimes an appropriate value LM of the amount of light to be output from the light source is calculated.

  Specifically, for each color of red, green, and blue, an appropriate light amount value L0 for the corresponding color specified at the time of light amount adjustment, a reading resolution R0 at the time of light amount adjustment, a reading resolution R1 of the processing target mode, Based on the above, the appropriate value LM of the amount of light to be output from the light source of the corresponding color at the time of reading the document in the processing target mode is calculated according to the formula LM = k · L0 · (R1 / R0).

  Here, k is a correction coefficient, and is predetermined in the design stage as a real value satisfying 0 <k ≦ 1. The light quantity LM can be obtained by the expression LM = L0 · (R1 / R0) if the error is not taken into consideration, but if the error is taken into consideration, the line data is obtained by the expression LM = L0 · (R1 / R0). Each pixel value indicated by may be saturated. In this embodiment, the correction coefficient k is applied so that such a problem does not occur. The correction coefficient k may be determined in advance by an experiment or the like so that the above object can be achieved. For example, k = 0.8 can be set. In addition, when the operation mode (each parameter) at the time of light intensity adjustment is the same as the processing target mode (each parameter), the appropriate value LM in the processing target mode is exceptionally determined as the appropriate value obtained at the time of light intensity adjustment. The same value as L0 can be used.

  On the other hand, when the process proceeds to S740, the reading control unit 50 calculates an appropriate light quantity value LM to be output from the green light source 73G at the time of reading the document in the processing target mode based on the result of the light quantity adjustment process executed previously. Specifically, the document in the processing target mode is based on the appropriate light amount L0 for the green light source 73G specified at the time of adjusting the light amount, the reading resolution R0 at the time of adjusting the light amount, and the reading resolution R1 of the processing target mode. The appropriate value LM of the light amount to be output from the light source 73G at the time of reading is calculated in accordance with the expression LM = k · L0 · (R1 / R0), similarly to the processing in S730.

  When the appropriate value LM is calculated in S730 or S740, the reading control unit 50 sets the light amount output from the corresponding light source during the main scan in the processing target mode to the calculated appropriate value LM (S750). Thereafter, the light amount calculation process is terminated, and the process proceeds to S370.

  In addition, when the process proceeds to S370, the reading control unit 50 acquires white data and black data for correcting the line data generated by the line sensor 31 during the main scan in the processing target mode. Specifically, when the processing target mode is “color”, the light source 73R, 73G, 73B is irradiated with light of the light amount LM set in the light amount calculation process in S360 from the corresponding light source, and the line sensor 31 is irradiated. The white reference member is read at the reading resolution corresponding to the processing target mode, and the line sensor 31 generates line data of the reading resolution based on the accumulated charge at the time of irradiation. Then, the line data is acquired as white data of the corresponding light source in the processing target mode.

  On the other hand, when the processing target mode is “monochrome”, the light of the light amount LM set in the light amount calculation processing in S360 is emitted from the green light source 73G, and the white reference is applied to the line sensor 31 with the reading resolution corresponding to the processing target mode. By reading the member, the line sensor 31 is caused to generate line data of the reading resolution based on the accumulated charge at the time of irradiation, and the line data is acquired as white data of the processing target mode. That is, when the processing target mode is “color”, white data for each light source is acquired, and when it is “monochrome”, white data of a green light source is acquired.

  In addition, the black data is generated by the line sensor 31 by causing the line sensor 31 to read the white reference member 29 at the reading resolution corresponding to the processing target mode without turning on the light sources 73R, 73G, and 73B. Line data is acquired as black data in the processing target mode. However, the reading time (charge accumulation time) of the white reference member 29 when the white data and black data are generated by the line sensor 31 is made to correspond to the reading time at the time of the main scan.

  When this process is completed, the reading control unit 50 determines whether or not the operation mode set for each document has been selected as the process target mode and the process of S360 has been executed (S380). If not, the process proceeds to S350, and one of the unprocessed operation modes is newly selected as the processing target mode, and the light amount calculation process for the processing target mode is executed (S360). In this manner, in S350 to S380, the amount of light output from the light source is set for each set operation mode, and black data and white data for each light source are acquired.

  If an affirmative determination is made in S380, the reading control unit 50 groups the original scan target originals placed on the original placement table 21a into originals for which a common operation mode is set, and for each group. The reading order is determined (S390). Specifically, for each group, a document (first document) placed most upstream in the sub-scanning direction among the document group belonging to the group is specified. Then, the placement position of the first document in each group (the position of the point most upstream of the document in the sub-scanning direction) is regarded as the head position of each group, and the head position is read sequentially from the group in the upstream in the sub-scanning direction. In this way, the group reading order is set. If the operation modes of the originals to be scanned are all different, only one original belongs to the group for each group.

  When this process is finished, the reading control unit 50 sets the group whose reading order is the head as the processing target group (S400). Then, the document group belonging to the processing target group is classified for each document group to be collectively read (S410).

  In this embodiment, the originals belonging to the processing target group are sequentially read from the original located upstream in the sub-scanning direction. However, as a placement mode of the document group belonging to the processing target group, when viewed in a one-dimensional coordinate system along the sub-scanning direction, the document is arranged apart as shown in FIGS. There are cases where the originals are arranged so as to overlap each other as shown in FIG. In the case where the originals are arranged apart like the originals A and C in FIG. 8B, when the reading operation is performed even in the area where the originals A and C are not arranged, the line sensor 31 at the time of the reading operation. Due to the low transport speed, the processing time is unnecessarily long. Therefore, it is more efficient to move the line sensor 31 between the originals A and C at a high speed and read the originals A and C individually.

  On the other hand, in the case where the originals are arranged so as to overlap each other as shown in FIG. 8C, after the original A is read, the line sensor 31 is retracted to the top position of the original B, and the originals A, Rather than reading B individually, it is more efficient to continuously convey the line sensor 31 to the area of the document group arranged in an overlapping manner and read these documents all at once.

  For this reason, in S410, the document is grouped for each group of documents to be collectively read. Specifically, in S410, the document group of the processing target group is classified for each document group whose distance from an adjacent document is less than a predetermined distance in a one-dimensional coordinate system along the sub-scanning direction. Hereinafter, the classified document group is expressed as a small group. According to this method, only the originals that are separated from the adjacent originals by the predetermined distance or more are classified into one small group. The predetermined distance is determined by the designer in advance so that the line sensor 31 does not have to be moved backward in consideration of the distance required for the run until the line sensor 31 shifts from the stopped state to the constant speed state. Good.

  When the processing in S410 is completed, the reading control unit 50 sets the small group located most upstream in the sub-scanning direction among the small group groups constituting the processing target group as the processing target small group (S420). Then, the motor 37 is controlled, and the line sensor 31 is arranged at a point upstream by the run-up distance from the leading edge of the document located most upstream in the sub-scanning direction of the processing target small group (S430).

  Thereafter, correction data corresponding to the operation mode of the processing target group is generated based on the white data and black data of the operation mode (S440), and in parallel with this processing, reading of the original corresponding to the processing target small group is performed. The operation is executed by the line sensor 31 (main scan: S450).

  Specifically, in S440, as a correction amount of the line data output from the line sensor 31 in the operation mode, a shading correction amount β and a black correction amount γ are calculated for each pixel by a known technique, and the shading correction is performed. Correction data describing the amount β and the black correction amount γ is generated. FIG. 9A is a conceptual diagram of correction data.

  More specifically, in S440, the shading correction amount β is obtained for each pixel from the value DW indicated by the white data and the value DB indicated by the black data according to the equation β = (E−1) / (DW−DB). At the same time, the black correction amount γ = DB is obtained. The variable E is the number of gradations E of the read image data that is finally generated as a result of reading the original.

  In the present embodiment, using the correction data generated here, in S460, the line data after digital conversion obtained from the line sensor 31 via the A / D converter 57 is subjected to shading correction and black correction, and line correction is performed. The value of the line data output from the sensor 31 is converted into a pixel value Y having the number of gradations E. For example, when the pixel value of the line data output from the line sensor 31 is X, the pixel value Y after shading correction and black correction is obtained by the equation Y = β · (X−γ). When the operation mode is “color”, the shading correction amount β for each color is obtained based on the white data and the black data for each color (light source) of red, green, and blue.

  In step S450, the motor 37 is controlled so that the line sensor 31 moves to the processing target group downstream of the document in the sub-scanning direction to the rear end point of the document that belongs to the processing target small group and is located most downstream. While conveying at a constant speed according to the corresponding operation mode, the line sensor 31 is caused to execute a reading operation in the operation mode corresponding to the processing target group, and the line sensor 31 is caused to generate line data corresponding to the operation mode. . At this time, the light amount LM set for the operation mode is output from the light source.

  Specifically, when the operation mode is “color”, the reading control unit 50 outputs the line start signal and the lighting control signals of the light sources 73R, 73G, and 73B in the pattern shown in FIG. , The line sensor 31 is caused to execute a reading operation (charge accumulation operation) at every 1/3 line period, which is a time interval in which the line sensor 31 is conveyed by 1/3 line, and 1/3. While switching the lighting color for each line cycle, the light sources 73R, 73G, 73B corresponding to the lighting color are lit for a time corresponding to the set light amount LM.

  FIG. 10A is a time chart showing a mode of a control signal input from the reading control unit 50 to the line sensor 31 at the time of reading in “color”. Further, the line start signal outputs the accumulated charge of the light receiving element to the transfer circuit 75 to transfer the charge information of the line that has been read to the transfer circuit 75 as line data and to reset the signal charge of the light receiving element. Control signal. Through such control, the line sensor 31 outputs line data representing red pixel values (red line data) and line data representing green pixel values (green) as color line data every 1/3 line cycle. Line data) and line data representing blue pixel values (blue line data) are sequentially output.

  On the other hand, when the operation mode is “monochrome”, the reading control unit 50 inputs the line start signal and the lighting control signal of the light source 73G to the line sensor 31 in the pattern shown in FIG. The line light source 73G is set for each line period in accordance with the input of the line start signal, while causing the line sensor 31 to perform a reading operation for each line period which is a time interval in which one line is conveyed. The light is turned on for a time corresponding to the light quantity LM. By such control, the line sensor 31 outputs line data representing a reading result by the green light source 73G as monochrome line data for each line cycle.

  In addition, when the processing in S450 is completed in this way, the reading control unit 50 converts the line data group obtained from the line sensor 31 based on the correction data of the processing target group generated in S440 and performs the shading correction and the black data. In addition to correction (S460), each original area portion belonging to the small group to be processed is extracted for each original from the corrected line data group, and read image data representing the read result of each original is generated (S470). Then, the generated read image data for each original is output to the PC 65 through the communication interface 60 (S475).

  When the processing in S475 is completed, it is determined whether or not all the small groups classified in S410 have been selected as processing target small groups (S480). If not selected (No in S480), the current setting is made. The small group having the next reading order adjacent in the sub-scanning direction to the processing target small group is set as a new processing target small group (S485). Thereafter, the process proceeds to S430. In this way, in the present embodiment, the processing of S430 to S485 is repeated, the original is read collectively for each small group, and the read image data of the original is output to the PC 65. Note that the processing of S440 need only be executed once for the processing target group.

  If an affirmative determination is made in S480, the process proceeds to S490, where it is determined whether or not all the groups set in S390 have been selected as processing target groups. Is set as a new process target group (S495), and the process proceeds to S410. In this way, in this embodiment, the original is sequentially read for each original group having a common operation mode, and the read image data is output to the PC 65.

  For example, as shown in FIG. 8A, when the originals A, B, and C are placed, the originals are individually read in the order of the originals A, B, and C, and the read image data of each original is read. In the case shown in FIG. 8B, the originals are individually read in the order of the originals A, C, and B, and the read image data of each original is output. In addition, in the case shown in FIG. 8C, the originals A and B are collectively read, and then the original C is read to output read image data of each original.

  The configuration of the image reading apparatus 1 according to the present embodiment has been described above. According to the image reading apparatus 1, a plurality of documents placed on the document placing table 21a can be read in individual operation modes. Then, every time the operation mode is switched, the line sensor 31 is returned to the home position facing the white reference member, the white reference member is read in the corresponding operation mode, and the original reading characteristics (light quantity, etc.) are not set. Before reading, document reading characteristics for all operation modes are set in a batch. Therefore, according to the image reading apparatus 1 of the present embodiment, it is not necessary to perform conveyance control to return the line sensor 31 to the home position every time the operation mode (color / monochrome, reading resolution) is switched, and it is efficient. A plurality of documents placed on the document placing table 21a can be read in individual operation modes.

  Further, according to the present embodiment, the light amount adjustment is performed by setting the operation mode for light amount adjustment based on the operation mode set for each document, and from the appropriate light amount value L0 obtained thereby, An appropriate light quantity value LM in the operation mode set for the document is obtained by calculation. Therefore, according to the present embodiment, it is not necessary to perform the light amount adjustment for the operation mode designated by the user, and the light amount setting can be performed quickly. As a result, according to the present embodiment, it is possible to shorten the processing time of a series of image reading including light amount adjustment, and it is possible to provide the user with a high-performance image reading apparatus 1 in terms of processing speed.

In addition, according to the present embodiment, since the document is read for each operation mode, the number of operation mode switching can be reduced, and the processing time loss due to the operation mode switching can be reduced.
The correspondence relationship between the above embodiment and “Claims” is as follows. The reading unit described in “Claims” corresponds to the line sensor 31 in the above-described embodiment, and the conveyance unit corresponds to the carriage conveyance mechanism 40. The mode designation receiving means is realized by the processing of S260, the reading control means is realized by the processing of S450 to S475, and the reading characteristic setting means is realized by the processing of S220, S310 to S380. The operation of setting the correction amount of the line data described in “Claims” corresponds to the operation of acquiring white / black data equivalent to the correction data.

  In addition, the present invention is not limited to the above-described embodiments, and can take various forms. For example, in the above embodiment, in S330, the parameter relating to the reading resolution for adjusting the light amount is set to the lowest reading resolution among the reading resolutions set in S260 for each original to be scanned. If the time required for specifying the light amount L0 is ignored, the highest reading resolution may be set. In addition, the present invention can be applied to various devices having a function as an image reading apparatus such as a facsimile machine and a digital multifunction machine.

DESCRIPTION OF SYMBOLS 1 ... Image reading apparatus, 21a ... Original mounting table, 29 ... White reference member, 31 ... Line sensor, 33 ... Carriage, 35 ... Belt conveyance mechanism, 37 ... Motor, 40 ... Carriage conveyance mechanism, 50 ... Reading control part, 51 ... CPU, 53 ... ROM, 55 ... RAM, 57 ... A / D converter, 60 ... communication interface, 65 ... PC, 67 ... input device, 69 ... display device, 71 ... light receiving element group, 73R, 73G, 73B ... Light source, 75 ... transfer circuit, A0 ... mode setting screen, A1 ... preview display area, A2 ... setting operation area

Claims (5)

Light is emitted from the light source to the reading target, the light irradiated to the reading target is received by a light receiving circuit arranged in the main scanning direction, and the accumulated charge of each light receiving circuit arranged in the main scanning direction is read. if by forming a reading unit generates the line data consisting of pixel data group in the main scanning direction corresponding to the reading resolution in accordance with,
Transport means capable of transporting the reading unit in the sub-scanning direction;
A document placing table on which a document to be read is placed, the document placing table provided at a position where the reading unit can be transported by the transport unit;
A white reference member provided at a position where the reading unit can be conveyed by the conveying means;
As the operation mode at the time of reading of the original document placed on the document table, the designation of the operation mode regarding the reading resolution from the user, accept add mode designation receiving for each of the placed on the document table document Means,
For each group of documents that are controlled on the reading unit and the conveying unit and are placed on the document placing table and have the same operation mode, an area on which a document belonging to the group is placed while scanning said reading unit in the sub-scanning direction, the original manuscript to the reading unit in the specified the operation mode from the user through the mode designation accepting means is read by the main scanning direction, placing the document table Reading control means for generating read image data representing a reading result of the original composed of the line data group for each placed original;
Prior to the operation of the reading control means, the reading unit and the conveying means are controlled to cause the reading unit to read the white reference member at a position facing the white reference member, and the reading result of the white reference member Based on the above, for all operation modes designated by the user through the mode designation accepting means, the amount of light to be output from the light source and the amount of correction of the line data when reading the document in the operation mode are used as the document reading characteristics. Reading characteristic setting means for setting for each mode;
With
After the operation of the reading characteristic setting unit, the reading control unit is configured to transfer each of the originals placed on the original placing table in a corresponding operation mode according to the original reading characteristic set by the reading characteristic setting unit. And reading the image data representing the reading result of each original document by correcting the line data. When color is selected as the operation mode related to the color, a light source for each color is sequentially irradiated to the reading target, and the light for each color irradiated to the reading target is received by a light receiving circuit arranged in the main scanning direction. By sequentially receiving light, the line data including the pixel data group in the main scanning direction corresponding to the accumulated charge of the light receiving circuit is sequentially generated for each color, color line data is generated, and the operation related to the color When monochrome is selected as the mode, a light source of a specific color is irradiated to the reading target among the light sources for each color, and the light of the specific color irradiated to the reading target is received by the light receiving circuit. A reading unit that generates monochrome line data by generating the line data according to the accumulated charge of the light receiving circuit;
Transport means capable of transporting the reading unit in the sub-scanning direction;
A document placing table on which a document to be read is placed, the document placing table provided at a position where the reading unit can be transported by the transport unit;
A white reference member provided at a position where the reading unit can be conveyed by the conveying means;
As an operation mode at the time of reading each document placed on the document placement table, a user designates an operation mode related to the color using the color and monochrome options, and the document placed on the document placement table. and accept attach mode designation receiving means for each,
For each group of documents that are controlled on the reading unit and the conveying unit and are placed on the document placing table and have the same operation mode, an area on which a document belonging to the group is placed while scanning said reading unit in the sub-scanning direction, the operation mode designated by the user through the mode designation accepting means, the originals to said reading unit to read in the main scanning direction, the document table Reading control means for generating read image data representing a reading result of the original composed of the color or monochrome line data group for each placed original; and
Prior to the operation of the reading control means, the reading unit and the conveying means are controlled to cause the reading unit to read the white reference member at a position facing the white reference member, and the reading result of the white reference member Based on the above, for all operation modes designated by the user through the mode designation accepting means, the amount of light to be output from the light source and the amount of correction of the line data when reading the document in the operation mode are used as the document reading characteristics. Reading characteristic setting means for setting for each mode;
With
After the operation of the reading characteristic setting unit, the reading control unit is configured to transfer each of the originals placed on the original placing table in a corresponding operation mode according to the original reading characteristic set by the reading characteristic setting unit. And reading the image data representing the reading result of each original document by correcting the line data. The reading unit, by synthesis in accordance with the reading resolution of the respective charges accumulated in the light receiving circuits arranged in the main scanning direction, is the arrangement for generating the line data corresponding to the reading resolution,
The mode designation receiving means is determined by a combination of an operation parameter relating to the color and an operation parameter relating to the reading resolution as an operation mode at the time of reading each document placed on the document placing table, with color and monochrome options. the specified operation mode from the user, acceptance is for each of the placed on the document table document,
After the operation of the reading characteristic setting unit, the reading control unit is placed on the document table in an operation mode designated by the user through the mode designation receiving unit according to the document reading characteristic set by the reading characteristic setting unit. The read unit is caused to read each placed original, and the line data is corrected to generate read image data having a reading resolution and color suitable for the operation parameter for each of the originals. Item 3. The image reading apparatus according to Item 2. The reading characteristic setting unit determines an operation mode used for light amount setting based on an operation mode for each document designated by a user through the mode designation receiving unit when setting the light amount, and the determined operation mode uses the determined operation mode. A reading unit is caused to read the white reference member, and based on the reading result, an appropriate light amount is specified in the determined operation mode, and further, based on the specified light amount, the user designates the light amount through the mode designation receiving unit. calculating a proper amount of light in each designated operation mode according to the calculation result, the image of claim 1, wherein setting the amount of light output from the light source wherein when reading the document in each mode reader . The reading characteristic setting unit is an operation mode having a reading resolution that matches an operation mode having the lowest reading resolution or an operation mode having the highest reading resolution among the operation modes for each document designated by the user through the mode designation receiving unit. Is determined as an operation mode used for light amount setting, the white reference member is read by the reading unit in the determined operation mode, and an appropriate light amount is specified in the operation mode based on the reading result, Based on the specified light amount, an appropriate light amount is calculated in each operation mode designated by the user through the mode designation receiving unit, and each operation designated by the user through the mode designation receiving unit is calculated according to the calculation result. The image reading apparatus according to claim 1, wherein the amount of light output from the light source is set in a mode.

Images