JP2010016715A - Calibration apparatus and method thereof, calibration program and computer readable recording medium with the calibration program recorded thereon - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a calibration apparatus for more accurately calibrating a read image by calibrating image data read by an image input device on the basis of two image data items obtained in a state of uniform and low illuminance and a state of uniform and high illuminance. <P>SOLUTION: A calibration apparatus 1 is used for calibrating image data read by an image input device 100. First image data read by the image input device 100 in a first space, where light of first illuminance is uniformly incident to an imaging unit of the image input device 100, and second image data read by the image input device 100 in a second space, where light of second illuminance higher than the first illuminance is uniformly incident to the imaging unit of the image input device 100, are input to an input section 11. An analysis section 12 analyzes the first and second image data to produce calibration data for calibrating image data to be read by the image input device 100 when imaging an object to be imaged. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a calibration apparatus and method suitable for correcting image data read by an image input apparatus, a calibration program, and a computer-readable recording medium on which the calibration program is recorded.

  In recent years, small information terminals such as mobile phones and PDCs are equipped with an image input device that reads an image formed on a document such as paper. In an image input device mounted on such a small information terminal, a technique has been devised in which a drive circuit for driving liquid crystal and an optical sensor element are mounted in the same display panel. With this mounting technique, not only the image input device displays an image but also an image input like a general scanner. Furthermore, by processing the input image, the display panel unit of the image input device can be used as a touch panel.

  FIG. 18 shows a schematic structure of a display panel unit of an image input apparatus mounted on such a small portable information terminal. FIG. 18B is an enlarged view of a portion A in FIG. As shown in FIG. 18, the display panel unit 50 of the conventional image input device includes a display surface 51, a transparent protective layer 52, a photosensor 53, a light shielding layer 54, a liquid crystal substrate 55, a light source 56, and a case. 57. The display panel unit 50 also serves as a display unit and an imaging unit of the image input device. The display panel unit 50 displays an image on the display surface 51 and reads an image formed on a document in contact with the display surface 51.

  In the display panel unit 50 of FIG. 18, the light shielding layer 54 is for shielding light from the light source 56, but has an opening 54 a for allowing light emitted from the light source 56 to pass therethrough. The optical sensor 53 is composed of a plurality of optical sensor elements 53a arranged in a two-dimensional array, and is for converting the irradiated light into an electrical signal. The transparent protective layer 52 is a transparent protective layer for protecting the optical sensor 53.

  A light shielding layer 54 is formed on one surface of the liquid crystal substrate 55. An optical sensor 53 is provided on the surface opposite to the surface where the light shielding layer 54 and the liquid crystal substrate 55 are in contact with each other. A transparent protective layer 52 is provided on the liquid crystal substrate 55 so as to cover the optical sensor 53. The light source 56 is provided on the surface of the liquid crystal substrate 55 opposite to the surface on which the transparent protective layer 52 is provided.

  The light emitted from the light source 56 passes through the opening 54 a of the light shielding layer 54, hits an object on the display surface 51, and is reflected. Then, when the reflected light is detected by the optical sensor 53, the image on the display surface 51 is read.

  By the way, when reading an image of an object (imaging target) in contact with the display surface 51, it is ideal to reproduce the density value of the image monotonously. However, actually, even if an object with a uniform density is read due to variations in characteristics (for example, pixel sensitivity) of the respective optical sensor elements 53a constituting the optical sensor 53, the respective optical sensor elements 53a. The output signal from will vary. For this reason, it is accurate if calibration for obtaining uniform output from each photosensor element 53a is not performed on an object having a uniform density by correcting sensitivity variations between the photosensor elements 53a. I can't get an image.

  For example, Patent Document 1 discloses a calibration in which two or more density reference plates having different densities are photoelectrically scanned by an optical sensor array, and input image data is corrected using uncorrected density values obtained by the photoelectric scanning. Alternative methods have been proposed.

Further, in Patent Document 2, image data obtained by reading a white reference plate while a light source is turned on for a predetermined time is set as white reference image data, and further, the white reference is supplied while the light source is turned on for a time shorter than the light source lighting time. A calibration method has been proposed in which image data obtained by reading a plate is used as simulated black reference image data, and input image data is corrected using the white reference image data and the simulated black reference image data.
JP-A-61-53868 (published March 17, 1986) JP 2004-260474 A (published on September 16, 2004)

  In the display panel unit 50 of FIG. 18, the intensity of light emitted from the light source 56 to the display surface 51 is different between the central portion and the end portion of the display surface 51. FIG. 19 shows the state of the path of light emitted from the light source 56. FIG. 19B schematically shows the light intensity distribution on the display surface 51 of FIG. 19A, and FIG. 19C shows the display surface 51 in the region B of FIG. 19B. It is a graph which represents a brightness typically. As described above, the light emitted from the light source 56 is applied to the display surface 51 through the opening 54 a of the light shielding layer 54. For this reason, as shown in FIG. 19A, compared with the vicinity of the central portion of the display surface 51, the light irradiation amount at the end portion is different, and due to this difference, the central portion and the end portion of the display surface 51 are different. A difference occurs in the intensity of light. That is, as shown in FIG. 19C, the end portion of the display surface 51 becomes darker than the vicinity of the central portion.

  For this reason, when calibration is performed to correct the input image data, if the conventional calibration method is used, the above-described reference is caused by the difference in light intensity distribution between the vicinity of the center portion of the display surface 51 and the end portion. The plate is not illuminated uniformly. As a result, the reflected light reflected by the reference plate is not evenly applied to the optical sensor 53. That is, there is a difference in the intensity of light irradiated between the optical sensor element 53a located at the end of the optical sensor 53 and the optical sensor element 53a located near the center. FIG. 20 shows a state of an image obtained from the optical sensor 53 in this case. As shown in FIG. 20, it can be seen that the image at the end of the optical sensor 53 is darker than that near the center.

  In such a situation, when the characteristic variation of each photosensor element 53a of the photosensor 53 is corrected using the image shown in FIG. 20, the light intensity at the end of the photosensor 53 is low, so There has been a problem that the dynamic range of the optical sensor element 53a at the end becomes small.

  In view of the above problems, an object of the present invention is to correct image data read by an image input device based on two pieces of image data obtained in each of a uniform dark illuminance state and a uniform bright illuminance state. Accordingly, it is an object of the present invention to provide a calibration apparatus and method that can correct a read image more accurately, and a calibration program and a computer-readable recording medium that records the calibration program.

  In order to achieve the above object, a calibration device according to the present invention is a calibration device that corrects image data read by an image input device having an imaging unit including a plurality of photosensor elements, and has a first illuminance. First image data read by the image input device in a first space where light is uniformly incident on the plurality of photosensor elements, and light having a second illuminance brighter than the first illuminance. Input means for inputting second image data read by the image input device in a second space uniformly incident on the optical sensor element, and the first and second images input by the input means Analyzing means for analyzing data and generating correction data for correcting image data to be read when the image input device images the imaging object based on the analysis result; For example, characterized in that is.

  In the above calibration device, the first image data read in the first space in which the light with the first illuminance is uniformly incident on each photosensor element, and the second illuminance brighter than the first illuminance. In order to correct the image data read when the image input device captures the imaging object based on the second image data read in the second space where the light of the light is uniformly incident on each photosensor element Correction data is generated.

  For this reason, compared with the case where the incident light of each photosensor element is not uniform, the characteristic variation of each photosensor element can be corrected with high accuracy, so that correction data for correcting image data read by the image input device is corrected. Accuracy can be improved. As a result, it is possible to accurately calibrate image data read by the image input apparatus.

  In the first and second spaces, the image input device further includes a condition setting unit that defines the first and second spaces around the image input device so that the image data can be read by the image input device. Preferably it is.

  In this case, since the space around the image input device can be reliably set as the first and second spaces, the first and second image data read by the image input device can be obtained more accurately.

  The condition setting unit includes a first illuminance setting unit that defines the first space, and a second illuminance setting unit that defines the second space, and the first illuminance setting unit includes: The second illuminance is stored in the first storage box that stores the image input device and prevents the outside light from entering the image input device, thereby defining the first space. The setting unit includes a second storage box that stores the image input device, and a light source provided inside the second storage box, and the image input stored in the second storage box. It is preferable that the second space is defined by irradiating the device with light emitted from the light source.

  In this case, since the condition setting unit can be realized with a simple configuration, the cost of the calibration apparatus can be reduced.

  The condition setting unit includes a storage box that stores the image input device, and a light source provided inside the storage box. The image input device is stored in the storage box, and the image input device By preventing external light from entering, the second space is defined by irradiating the image input device stored in the storage box with light emitted from the light source. It is preferable to define a space.

  In this case, since the condition setting unit can be realized with a simple configuration, the cost of the calibration apparatus can be reduced.

  The image input device has an image pickup unit arrangement surface on which the image pickup unit is arranged, and the storage box is placed on the image pickup unit arrangement surface of the image input device when the image storage device stores the image input device. It is preferable to have an inner surface which is opposed and has an area larger than the imaging unit arrangement surface.

  In this case, since the imaging unit of the image input device can be reliably surrounded by the storage box, the first and second spaces can be reliably defined.

  The condition setting unit includes a first illuminance setting unit that defines the first space, and a second illuminance setting unit that defines the second space, and the first illuminance setting unit includes: The second illuminance includes the first processing chamber that houses the image input device and prevents the outside light from entering the image input device, thereby defining the first space. The setting unit includes a second processing chamber that houses the image input device, and a light source provided inside the second processing chamber, and the image input that is stored in the second processing chamber. The second space is demarcated by irradiating the apparatus with light emitted from the light source, and the condition setting unit further includes the image input device placed inside the first and second processing chambers. It has a transport unit that transports the image input device so that it can be stored sequentially. It is preferred that.

  In this case, the image input device is accommodated in the first processing chamber in which the first space is defined and the second processing chamber in which the second space is defined, for example, in this order by the transport unit. Will be. Therefore, by creating the first and second spaces in accordance with the conveyance of the image input device by the conveyance unit, it is possible to efficiently acquire image data read by the image input device in each space.

  The condition setting unit includes a processing chamber for storing the image input device, a light source provided in the processing chamber, and the image input device so that the image input device is stored in the processing chamber. The condition setting unit stores the image input device in the processing chamber by the transfer unit, and prevents external light from entering the image input device. Preferably, the first space is defined and the second space is defined by irradiating the image input apparatus accommodated in the processing chamber with light emitted from the light source.

  In this case, the image input apparatus is accommodated in the processing chamber in which the first and second spaces are defined without requiring movement. For this reason, the image data read by the image input device in each space can be efficiently acquired by sequentially defining the first and second spaces.

  The imaging unit of the image input device includes the plurality of optical sensor elements that convert the illuminance of incident light into an electrical signal having a voltage value corresponding to the illuminance, and the second illuminance is determined by the optical sensor. It is preferable that the electrical signal output from the element is less than the illuminance of incident light that saturates.

  In this case, since the output value of the optical sensor element does not saturate, the second image data read by the image input device can be acquired more accurately.

  The imaging unit of the image input device includes the plurality of photosensor elements that convert the illuminance of incident light into an electrical signal having a voltage value corresponding to the illuminance, and the analysis means includes the plurality of photosensors. For each of the elements, an output value of the photosensor element according to the first illuminance and an output value of the photosensor element according to the second illuminance are obtained, and the light is output based on the two output values. It is preferable to calculate an offset value and a gain value in conversion by the sensor element, and generate the offset value and the gain value as the correction data.

  In this case, since each optical sensor element can calculate using the offset value and the gain value when converting the illuminance of incident light into an electrical signal, conversion by each optical sensor element can be performed efficiently.

  The calibration program according to the present invention is a calibration program for operating a computer as each means in the calibration apparatus.

  In the above calibration program, the first image data read in the first space in which the light of the first illuminance is uniformly incident on each photosensor element, and the second illuminance brighter than the first illuminance In order to correct the image data read when the image input device captures the imaging object based on the second image data read in the second space where the light of the light is uniformly incident on each photosensor element Correction data is generated.

  For this reason, compared with the case where the incident light of each photosensor element is not uniform, the characteristic variation of each photosensor element can be corrected with high accuracy, so that correction data for correcting image data read by the image input device is corrected. Accuracy can be improved. As a result, it is possible to accurately calibrate image data read by the image input apparatus.

  A computer-readable recording medium according to the present invention is a computer-readable recording medium in which the calibration program is recorded.

  In the calibration program recorded on the recording medium, the first image data read in the first space where the light of the first illuminance is uniformly incident on each photosensor element, and the first illuminance Also read when the image input device captures an imaging object based on the second image data read in the second space in which the light having the second illuminance is uniformly incident on each photosensor element. Correction data for correcting the image data is generated.

  For this reason, compared with the case where the incident light of each photosensor element is not uniform, the characteristic variation of each photosensor element can be corrected with high accuracy, so that correction data for correcting image data read by the image input device is corrected. Accuracy can be improved. As a result, it is possible to accurately calibrate image data read by the image input apparatus.

  A calibration method according to the present invention is a calibration method for correcting image data read by an image input device having an imaging unit including a plurality of photosensor elements, wherein light having a first illuminance is the plurality of photosensor elements. First image data read by the image input device and light having a second illuminance brighter than the first illuminance are uniformly incident on the plurality of photosensor elements. Second image data read by the image input device in the second space, an input step for inputting the first image data, and the first and second image data input in the input step, Based on the result, an analysis step for generating correction data for correcting image data read when the image input device captures an imaging object; and the image input device When imaging the imaged object, on the basis of the correction data generated by the analyzing step, characterized by comprising a correction step of correcting the image data by the image input apparatus reads.

  In the above calibration method, the first image data read in the first space in which the light with the first illuminance is uniformly incident on each photosensor element, and the second illuminance brighter than the first illuminance. In order to correct the image data read when the image input device captures the imaging object based on the second image data read in the second space where the light of the light is uniformly incident on each photosensor element Correction data is generated.

  For this reason, compared with the case where the incident light of each photosensor element is not uniform, the characteristic variation of each photosensor element can be corrected with high accuracy, so that correction data for correcting image data read by the image input device is corrected. Accuracy can be improved. As a result, it is possible to accurately calibrate image data read by the image input apparatus.

  In the present invention, as described above, the first image data read by the image input device in the first space in which the light of the first illuminance is uniformly incident on the plurality of photosensor elements, and the first Second image data read by the image input device in a second space where light having a second illuminance brighter than the illuminance is uniformly incident on the plurality of photosensor elements; Analyzing the first and second image data input by the input means, and based on the analysis result, correction data for correcting image data to be read when the image input device images the imaging object. And an analyzing means for generating.

  Therefore, by correcting the image data read by the image input device based on the two image data obtained in each of the uniform dark illuminance state and the uniform bright illuminance state, the correction of the read image is further improved. There is an effect that it can be performed accurately.

  Embodiments of the present invention will be described below with reference to the drawings. In the following description, the same parts are denoted by the same reference numerals. Their names and functions are also the same. Therefore, detailed description thereof will not be repeated.

(Embodiment 1)
The calibration apparatus according to the first embodiment of the present invention has two different illumination conditions (hereinafter referred to as “dark condition (first illumination condition)” and “bright condition (second illumination condition)”). Each image data (hereinafter referred to as “dark data (first image data)” and “bright data (second image data)” read by the image input device in each space (first space and second space). The correction data for correcting the image data read by the image input device is obtained based on the two acquired image data, and is output to the image input device.

  Here, the correction data is used to correct nonuniformity in the illuminance (light emission luminance) of the light source, variations in characteristics (for example, pixel sensitivity) of each photosensor element constituting the photosensor, and so on. This is data for obtaining a uniform output for an image, and this correction data is used when correcting image data read by the image input device.

  FIG. 1 is a block diagram showing the configuration of the calibration apparatus according to the first embodiment of the present invention. As shown in FIG. 1, the calibration apparatus 1 according to the present embodiment includes a calibration unit 10 that generates correction data for correcting image data read by the image input apparatus 100 and the image input apparatus 100 described above. A condition setting unit 20 capable of setting each of a dark condition and a light condition.

  Furthermore, in the calibration device 1 according to the present embodiment, the calibration unit 10 includes an input unit (input unit) 11, an analysis unit (analysis unit) 12, a storage unit 13, and an output unit 14. Have. The condition setting unit 20 includes a dark condition setting unit 21 and a bright condition setting unit 22.

  An example of the image input device that is calibrated by the calibration device 1 according to the present embodiment is a small information terminal having both functions of image display and image input. FIG. 2 shows a functional block diagram of a schematic configuration of the small information terminal. As shown in FIG. 2, the image input apparatus 100 includes a display unit 101 having a liquid crystal for displaying information, an organic EL (organic electroluminescence), etc., an imaging unit 102 for optically reading an image, A memory 104 including a CPU (Central Processing Unit) 103 that performs various controls in the image input apparatus 100, a ROM (Read Only Memory) that stores programs executed by the CPU 103, work data, and the like, a RAM (Random Access Memory), and the like. And have. The display unit 101 that displays an image and the imaging unit 102 that reads an image implement, for example, the display panel unit 50 shown in FIG. FIG. 3 shows an overall view of the image input apparatus 100. As shown in FIG. 3, the image input device 100 is provided with a display panel surface (imaging unit arrangement surface) on which the display panel unit 50 (the display unit 102 and the imaging unit 103) is arranged. 100 users can display images and input images using the display panel unit 50.

  Hereinafter, in the embodiment of the present invention, a calibration apparatus 1 for calibrating image data read by the image input apparatus 100 shown in FIG. 2 will be described as an embodiment. Further, it is assumed that the display unit 101 and the imaging unit 102 of the image input apparatus 100 in FIG. 2 have the same configuration as the display panel unit 50 in FIG.

  In the calibration unit 10 of the present embodiment, the input unit 11 includes dark data (first image data) that is read image data of the image input device 100 under dark conditions, and an image input device under bright conditions. Bright data (second image data) that is 100 read image data is input from the image input apparatus 100. The input unit 11 is connected to the imaging unit 102 of the image input apparatus 100, and the dark data and the bright data acquired by the imaging unit 102 are input thereto.

  The analysis unit 12 analyzes the dark data and the bright data input from the input unit 11 and calculates correction data for correcting the read image data of the image input device 100. The storage unit 13 stores the correction data calculated by the analysis unit 12. The storage unit 13 can be appropriately selected and used from a magnetic disk device such as a hard disk drive or a known storage device such as a semiconductor memory.

  The output unit 14 reads the correction value from the storage unit 13 and outputs the read correction value to the image input apparatus 100.

  In the condition setting unit 20 of the present embodiment, the dark condition setting unit 21 is capable of emitting light with dark illuminance so as to uniformly irradiate light with dark illuminance onto the entire optical sensor 53 of FIG. . The dark condition setting unit 21 may be anything that can realize the dark condition by surrounding the entire image input apparatus 100 and blocking external light from entering the image input apparatus 100, for example. Specifically, as shown in FIG. 4, for example, the image input device 100 can be stored, and can be realized by a substantially rectangular parallelepiped storage box 211 that surrounds the entire image input device 100 and blocks the incidence of external light. is there. In addition, the storage box 211 has an inner surface facing the display panel surface of the image input device 100 larger than the display panel surface so that the image input device 100 can be completely stored.

  More specifically, the inside of the storage box 211 is preferably coated with a light absorbing material. Examples of the coating method include a method of painting using a pigment (carbon black) or the like as a coating material, and a method of plating a metal such as black chrome, black nickel or black zinc as a coating material. Simply, black paper may be pasted inside the storage box 211. When the image input apparatus 100 is stored in the storage box 211, the interior of the storage box 211 can be maintained at a certain dark illuminance by the coating or the like, so that the entire light sensor 53 is uniformly irradiated with light having a dark illuminance. be able to. In order to more effectively prevent external light from entering the storage box 211, for example, it is more preferable to lay a sponge, rubber, or the like on the edge of the storage box 211.

  On the other hand, the bright condition setting unit 22 is capable of emitting light having a bright illuminance so as to uniformly irradiate the entire light sensor 53 of FIG. 18 with light having a bright illuminance. The bright condition setting unit 22 may be anything that can realize the above-described bright condition by, for example, surrounding the entire image input apparatus 100 and irradiating the entire image input apparatus 100 with light having a bright illuminance. Specifically, for example, as shown in FIG. 5, the image input apparatus 100 can be stored in a storage box 221 having a substantially rectangular parallelepiped shape, in which a light source 222 is provided, and the light source 222 emits light with bright illuminance. It is feasible. In addition, the storage box 221 has an inner surface facing the display panel surface of the image input device 100 larger than the display panel surface so that the image input device 100 can be completely stored.

  More specifically, it is preferable that the light source 222 provided inside the storage box 221 can emit light that can make the illuminance of the entire storage box 221 constant. As the light source 222, for example, an organic EL light, a panel type white LED (light emitting diode) light, or the like may be used. Further, the light source 222 does not have to be provided in the entire interior of the storage box 221. As shown in FIG. 5, when the image input apparatus 100 is stored in the storage box 221, the light source 222 is displayed on the display panel portion of the image input apparatus 100. 50 may be installed on the inner surface of the storage box 221 facing 50. Of course, it is not always necessary to provide it on the inner surface facing the light source 222, and the light intensity of the light emitted from the light source 222 is large, and the illuminance of the entire storage box 211 is constant brightness regardless of which of the inner surfaces of the storage box 221 is present. However, the installation of the light source 221 is not limited to the facing surface.

  The illuminance in the storage box 221 realized by the light emitted from the light source 222 is set to a value that does not saturate the output value of each photosensor element 53 a that constitutes the photosensor 53. Each optical sensor element 53a converts an electrical signal having a voltage value corresponding to the illuminance of incident light. When the illuminance of incident light exceeds the illuminance range that can be converted by each optical sensor element 53a, The voltage value of the electric signal output from the sensor element 53a is saturated, and each optical sensor element 53a does not function as an optical sensor element. For this reason, it is preferable that the illuminance in the storage box 221 is set to be less than the illuminance of incident light (hereinafter referred to as “saturated maximum illuminance”) at which the output value of each optical sensor element 53a is saturated. Therefore, if the illuminance in the storage box 221 depends on the output light power of the light source 222, the output light power of the light source 222 is set so that the illuminance in the storage box 221 is less than the saturation maximum illuminance. Is preferred.

  Next, operation | movement of the calibration apparatus 1 concerning this Embodiment is demonstrated using FIG. FIG. 6 is a flowchart for explaining the operation of the calibration apparatus 1. Here, an example in which the storage box 211 in FIG. 4 is used as the dark condition setting unit 21 and the storage box 221 in FIG. 5 is used as the bright condition setting unit 22 will be described.

  In FIG. 6, the dark condition setting unit 21 of the calibration device 1 sets a dark condition for the image input device 100 (step S <b> 101), and the dark condition setting unit 21 realizes the dark condition in accordance with the realization of the dark condition. Dark data, which is image data acquired by the optical sensor 53, is input to the input unit 11 (step S102).

  In step S <b> 101 and step S <b> 102, as shown in FIG. 7, first, after the image input device 100 is disposed on the main surface such as a work table, the storage box 211 is disposed above the image input device 100. . Then, the storage box 211 is lowered so that the image input apparatus 100 is completely surrounded by the storage box 211, and the storage box 211 is arranged on the image input apparatus 100.

  After the storage box 211 stores the image input device 100, image data is acquired by the optical sensor 53 of the image input device 100, and the acquired image data is input to the input unit 11 as dark data.

  Here, when acquiring the dark data, the light source of the image input apparatus 100 itself may be in the on state or in the off state. In any case, the realization of the dark condition by the storage box 211 suppresses the light emitted from the light source of the image input apparatus 100 itself from affecting the optical sensor 53 of the image input apparatus 100. is there.

  The bright condition setting unit 22 of the calibration device 1 sets a bright condition for the image input device 100 (step S103), and the light sensor 53 of the image input device 100 is used in accordance with the realization of the bright condition by the bright condition setting unit 22. Bright data, which is acquired image data, is input to the input unit 11 (step S104).

  In step S <b> 103 and step S <b> 104, as shown in FIG. 8, first, after the image input device 100 is disposed on the main surface such as a workbench, the storage box 221 is disposed above the image input device 100. . Then, the storage box 221 is lowered so that the image input apparatus 100 is completely surrounded by the storage box 221, and the storage box 221 is arranged on the image input apparatus 100.

  After the storage box 221 stores the image input device 100, image data is acquired by the optical sensor 53 of the image input device 100, and the acquired image data is input to the input unit 11 as bright data.

  Here, when the bright data is acquired, the light source of the image input apparatus 100 itself may be in the on state or in the off state. In any case, the realization of the dark condition by the storage box 221 suppresses the light emitted from the light source of the image input apparatus 100 itself from affecting the optical sensor 53 of the image input apparatus 100. is there.

In this way, dark data and bright data are input to the input unit 11 of the calibration apparatus 1. As the dark data and the bright data, for example, the output value of each photosensor element 53a constituting the photosensor 53 is input as data represented as an 8-bit digital quantity. In this case, the illuminance of the incident light of each optical sensor element 53a is output as a digital signal having a gradation of 2 ⁸ = 256 (0 to 255).

  Next, the analysis unit 12 of the calibration apparatus 1 acquires dark data and bright data input from the input unit 11 and performs correction for correcting image data that the image input apparatus 100 acquires by the optical sensor 53 during normal operation. Data is calculated (step S105).

In step S <b> 105, the analysis unit 12 acquires a 256-gradation digital signal that is an output value of each photosensor element 53 a constituting the photosensor 53 for each of dark data and bright data. And the analysis part 12 calculates the correction data about each optical sensor element 53a by performing a calibration process about each optical sensor element 53a. Hereinafter, the calibration process will be described with reference to FIG. Here, among the output values of the respective optical sensor elements 53a constituting the optical sensor 53, the output value for the dark data is bb _i , and the output value for the bright data is wb _i .

  In this calibration process, correction data for the optical sensor element 53a is calculated according to the following procedure.

(1) As shown in FIG. 9A, bb _i and wb _i of the optical sensor element 53a are mapped, and the value of bb _i is set as an offset value offset0 _i .

(2) As indicated by arrows C and D in FIG. 9A, the offset value offset0 _i is subtracted from each of bb _i and wb _i of the optical sensor element 53a. That is, bb _i and wb _i are translated so that bb _i is mapped to pixel value 0.

(3) As shown in FIG. 9B, the subtracted values of bb _i -offset0 _i and wb _i -offset0 _i are mapped again.

(4) As shown by an arrow E in FIG. 9B, wb _i -offset0 _i is mapped to a pixel value 255, and a gain value gain0 _i is calculated by the following equation. Note that, as indicated by an arrow F in FIG. 9B, bb _i -offset0 _i is set to the pixel value 0 as it is.

gain0 _i = 255 / (wb _i -offset0 _i )
The above equation is derived from the following equation representing mapping of wb _i -offset0 _i to pixel value 255.

255 = gain0 _i × (wb _i −offset0 _i )
In this manner, the analysis unit 12 can calculate each of the offset value offset0 _i and the gain value gain0 _i , which are correction data for each optical sensor element 53a. Then, the analysis unit 12 calculates each of the offset value offset0 _i and the gain value gain0 _i for each photosensor element 53a, and stores them in the storage unit 13 in association with each photosensor element 53a.

The output unit 14 of the calibration apparatus 1 takes out each of the offset value offset0 _i and the gain value gain0 _i for each photosensor element 53a from the storage unit 13, and outputs them to the image input apparatus 100 (step S106).

  Note that the processing in steps S <b> 101 to S <b> 106 is usually performed before shipping the image input apparatus 100, but may be performed after shipping.

  Next, the operation of the image input apparatus 100 that has received the correction data output from the calibration apparatus 1 will be described with reference to FIG. FIG. 10 is a flowchart for explaining the operation of the image input apparatus 100.

In FIG. 10, the image input apparatus 100 receives the correction data output from the calibration apparatus 1 as an offset value offset0 _i and a gain value gain0 _i associated with each photosensor element 53a, and stores them in the memory 104 (step S201). ).

When the acquisition of image data by the imaging unit 102 is started, the CPU 103 of the image input device 100 takes out the offset value offset0 _i and the gain value gain0 _i of each optical sensor element 53a from the memory 104 (S202), and each optical sensor element to the output value of 53a, using the offset value offset0 _i and the gain value GAIN0 _i corresponding to each photosensor element 53a, corrects the output value of each photosensor element 53a (step S203).

  The CPU 103 of the image input apparatus 100 displays the image data read by the imaging unit 102 on the display unit 101 based on the output value of each photosensor element 53a corrected by itself (step S204).

Next, the correction process of the output value of each photosensor element 53a in step S203 will be described with reference to FIG. Here, among the output values of the respective optical sensor elements 53a constituting the optical sensor 53, the output value for dark data is bb _i , the output value for bright data is wb _i , and the normal value to be corrected The output value is sd _i .

  In this correction process, the correction value of the output value of the optical sensor element 53a is calculated by the following procedure.

(1) As shown in FIG. 11, sd _i of the optical sensor element 53a is mapped.

(2) As indicated by the arrow G in FIG. 11, the offset value offset0 _i is subtracted from the sd _i of the optical sensor element 53a, and the gain value gain0 _i is multiplied by the subtraction result sd _i -offset 0 _i .

That is, the correction value of sd _i of the optical sensor element 53a can be calculated by the following equation.

sd _i correction value = (sd _i −offset 0 _i ) × gain 0 _i
In this way, the CPU 103 can calculate the correction value of the output value for each optical sensor element 53a.

(Embodiment 2)
Next, a second embodiment of the present invention will be described. The first embodiment described above is an embodiment for explaining an example in which the dark condition setting unit 21 and the bright condition setting unit 22 are realized by separate storage boxes. On the other hand, the present embodiment is an embodiment for explaining an example in which the dark condition setting unit 21 and the bright condition setting unit 22 of the first embodiment are realized using the same storage box. The dark condition setting unit 21 and the bright condition setting unit 22 are the same as those in the first embodiment except that the same storage box is used, and only this difference will be described here.

  As described above, in the condition setting unit 20 of the present embodiment, the dark condition setting unit 21 and the bright condition setting unit 22 are realized by the same storage box. Specifically, as shown in FIG. 12, for example, the image input device 100 can be stored, the outside of the external light is blocked by surrounding the entire image input device 100, and a light source 213 is provided therein. The light source 213 can be realized by a storage box 212 having a substantially rectangular parallelepiped shape that can emit light with bright illuminance. The storage box 212 can realize the dark condition and the bright condition by switching the state of the light source 213 between lighting / extinguishing, and by doing so, the manufacturing cost of the calibration apparatus 1 can be reduced.

  As the light source 213 of this embodiment, for example, an organic EL light, a panel type white LED (light emitting diode) light, or the like may be used. In FIG. 12, the light source 213 is provided in the entire interior of the storage box 212, but it is not always necessary to provide it in the entire interior as in the above embodiment, and the light source 213 is provided in the display panel unit 50 of the image input apparatus 100. You may install in the inner surface of the storage box which opposes. Of course, it is not always necessary to provide it on the inner surface facing the light source 213, and the light intensity of the light emitted from the light source 213 is large, and the illuminance of the entire storage box 212 is constant brightness regardless of which of the inner surfaces of the storage box 212 is present. However, the installation of the light source 213 is not limited to the facing surface.

  Further, in the case where the light source 213 is not provided in the entire interior of the storage box 212, a light absorbing material may be coated on the other interior of the storage box 212 as in the first embodiment. Of course, you can simply paste black paper. Furthermore, in order to more effectively prevent external light from entering the storage box 212, for example, it is more preferable to lay a sponge, rubber, or the like on the edge of the storage box 212.

  Next, operation | movement of the calibration apparatus 1 concerning this Embodiment is demonstrated using FIG. FIG. 13 is a flowchart for explaining the operation of the calibration apparatus 1. Here, an example in which the storage box 212 of FIG. 12 is used as the dark condition setting unit 21 and the bright condition setting unit 22 will be described.

  In FIG. 13, the dark condition setting unit 21 of the calibration apparatus 1 sets a dark condition for the image input apparatus 100 (step S <b> 301). Dark data, which is image data acquired by the optical sensor 53, is input to the input unit 11 (step S302).

  In step S <b> 301 and step S <b> 302, first, after the image input device 100 is disposed on the main surface such as a work table, the storage box 212 is disposed above the image input device 100. Then, the storage box 212 is lowered so that the image input apparatus 100 is completely surrounded by the storage box 212, and the storage box 212 is arranged on the image input apparatus 100.

  After the storage box 212 stores the image input apparatus 100, image data is acquired by the optical sensor 53 of the image input apparatus 100, and the acquired image data is input to the input unit 11 as dark data. At the time of this acquisition, the state of the light source 213 in the storage box 212 is turned off.

  The bright condition setting unit 22 of the calibration device 1 sets a bright condition for the image input device 100 (step S303), and the light sensor 53 of the image input device 100 is used in accordance with the realization of the bright condition by the bright condition setting unit 22. Bright data, which is acquired image data, is input to the input unit 11 (step S304).

  In step S <b> 303 and step S <b> 304, first, after the image input device 100 is disposed on the main surface such as a work table, the storage box 212 is disposed above the image input device 100. Then, the storage box 212 is lowered so that the image input apparatus 100 is completely surrounded by the storage box 212, and the storage box 212 is arranged on the image input apparatus 100.

  After the storage box 212 stores the image input apparatus 100, image data is acquired by the optical sensor 53 of the image input apparatus 100, and the acquired image data is input to the input unit 11 as bright data. At the time of this acquisition, the state of the light source 213 in the storage box 212 is turned on.

  In this way, dark data and bright data are input to the input unit 11 of the calibration apparatus 1.

Next, the analysis unit 12 of the calibration apparatus 1 acquires dark data and bright data input from the input unit 11 and performs correction for correcting image data that the image input apparatus 100 acquires by the optical sensor 53 during normal operation. Data is calculated (step S305). Then, the analysis unit 12 calculates each of the offset value offset0 _i and the gain value gain0 _i for each photosensor element 53a, and stores them in the storage unit 13 in association with each photosensor element 53a.

The output unit 14 of the calibration device 1 takes out each of the offset value offset0 _i and the gain value gain0 _i for each photosensor element 53a from the storage unit 13, and outputs them to the image input device 100 (step S306).

  The processes in steps S301 to S306 are usually performed before shipment of the image input apparatus 100, but may be performed after shipment.

  Note that the operation of the image input apparatus 100 that has received the correction data output from the calibration apparatus 1 is the same as that of the first embodiment, and therefore description thereof will not be repeated here.

  In each of the above embodiments, the dark condition setting unit 21 and the light condition setting unit 22 are realized using a substantially rectangular parallelepiped storage box. However, the present invention is not particularly limited to this example, and a substantially cylindrical storage box is used. You may use. In this case, the bright condition setting unit 22 preferably has a larger radius of the substantially cylindrical shape. By doing so, the light from the light source is evenly irradiated by the display panel unit of the image input device, and more stable light conditions can be realized.

  In each of the above embodiments, the light condition setting unit 22 is realized by using a light source provided in a substantially rectangular parallelepiped storage box. However, the present invention is not limited to this example, and the storage box is not used. The bright condition may be realized by irradiating light from the light source. In this case, the light source to be used may be a light source that can irradiate the display panel unit 50 of the image input apparatus 100 with light with uniform bright illuminance.

(Embodiment 3)
Next, a third embodiment of the present invention will be described. In the first and second embodiments, the dark condition setting unit 21 and the bright condition setting unit 22 of the condition setting unit 20 are realized by using separate bodies or the same storage box, and are arranged on the main surface of the work table, for example. In this embodiment, the image input device 100 is stored in each storage box by lowering the storage box from above the image input device 100.

  On the other hand, in the present embodiment, an example will be described in which the dark condition setting unit 21 and the bright condition setting unit 22 are realized using two processing chambers, and the image input apparatus 100 is sequentially passed through the processing chambers. It is a form. The dark condition setting unit 21 and the bright condition setting unit 22 are the same as those in the first and second embodiments except that the two processing chambers are used. Only the different points will be described here.

  FIG. 14 is a configuration diagram of a condition setting unit according to the present embodiment. In the condition setting unit 20a according to the present embodiment, as shown in FIG. 14, a dark condition processing chamber 311 and a light condition processing chamber are provided on a belt (conveyance unit) 321 circulated by driving units (conveyance units) 331 and 332. 312 is installed.

  The dark condition processing chamber 311 has an inlet 313a and an outlet 313b. The inlet 313a and the outlet 313b are basically closed and are opened and closed only when the image input apparatus 100 enters and exits. The inlet 313a and the outlet 313b may be configured using, for example, an opening / closing door, and as a mechanism for opening / closing, there is a method of sliding the opening / closing door mechanically. Further, instead of providing such an opening / closing door, a cloth may be simply hung on the inlet 313a and the outlet 313b.

  The bright condition processing chamber 312 also has an inlet 315a and an outlet 315b. The configurations of the inlet 315a and the outlet 315b are the same as the configurations of the inlet 313a and the outlet 313b of the dark condition processing chamber 311.

  The image input device 100 is disposed on the belt 321 and passes through the dark condition processing chamber 311 and the light condition processing chamber 312 by the circulation of the belt 321 by the driving units 331 and 332. An object detection sensor 322 is provided near the entrance 313 a of the dark condition processing chamber 311, and the position of the image input device 100 approaching the dark condition processing chamber 311 is detected by the object detection sensor 322. When the image input apparatus 100 enters the dark condition processing chamber 311, the circulation of the belt 321 is stopped, and acquisition of dark data is started. As the object detection sensor 322, a photo interrupter, an ultrasonic sensor, or the like may be used.

  After the acquisition of dark data, the circulation of the belt 321 by the drive units 331 and 332 is started again, and the image input apparatus 100 goes out of the dark condition processing chamber 311. The dark condition processing chamber 311 can store the image input device 100, covers the entire image input device 100, blocks the incidence of external light, and the inside is coated with a light absorbing material. It is a processing chamber that can be realized. As the light absorbing material, for example, a method of coating a pigment, a method of plating a metal such as black chrome, black nickel, or black zinc may be used. Of course, you can simply paste black paper.

  An object detection sensor 323 is also provided near the entrance 315a of the bright condition processing chamber 312. The configuration of the object detection sensor 323 is the same as the configuration of the object detection sensor 322 in the dark condition processing chamber 311. When the image input apparatus 100 enters the bright condition processing chamber 312, the circulation of the belt 321 is stopped and the acquisition of bright data is started.

  After the bright data is acquired, the belts 321 are circulated again by the drive units 331 and 332, and the image input apparatus 100 exits from the bright condition processing chamber 312. The bright condition processing chamber 312 can store the image input device 100, covers the entire image input device 100, blocks incident external light, and has a light source 314 provided therein. The light source 314 can emit light with a bright illuminance, and a bright condition can be realized in the bright condition processing chamber 312.

  As the light source 314, for example, an organic EL light, a panel type white LED (light emitting diode) light, or the like may be used. In FIG. 14, the light source 314 is installed inside the bright condition processing chamber 312 facing the display panel unit 50 of the image input apparatus 100, but may be provided inside the entire interior. Of course, it is not always necessary to provide the light source 314 on the inner surface. Even when the light emitted from the light source 314 has a large power and is on one of the inner surfaces of the light condition processing chamber 312, As long as the illuminance can be made constant, the installation of the light source 314 on the facing surface is not limited.

  The control unit 333 is connected to each of the drive units 331 and 332, the dark condition processing chamber 311, the bright condition processing chamber 312, and the object detection sensors 322 and 323, and is connected to each of the dark condition processing chamber 311 and the bright condition processing chamber 312. Controls the entry and exit of the image input device 100. Specifically, when the image input device 100 is disposed on the belt 321, the control unit 333 starts driving the drive units 331 and 332 and moves the image input device 100 to the dark condition processing chamber 311 side. The object detection sensor 322 detects the position of the image input device 100, and the control unit 333 shifts the entrance 313a of the dark condition processing chamber 311 from the closed state to the open state based on the detection signal. After the image input apparatus 100 enters the dark condition processing chamber 311, the control unit 333 causes the entrance 313 a to move to the closed state again. After completion of dark data acquisition in the dark condition processing chamber 311, the control unit 333 causes the exit 313 b of the dark condition processing chamber 311 to shift from the closed state to the open state, and then causes the image input device 100 to exit the dark condition processing chamber 311. . After leaving the image input apparatus 100 from the dark condition processing chamber 311, the control unit 333 causes the outlet 313 b of the dark condition processing chamber 311 to shift to the closed state again.

  Similarly, the control unit 333 moves the image input device 100 to the bright condition processing chamber 312 side. The object detection sensor 323 detects the position of the image input apparatus 100, and the control unit 333 shifts the entrance 315a of the bright condition processing chamber 312 from the closed state to the open state based on the detection signal. After the image input apparatus 100 enters the bright condition processing chamber 312, the control unit 333 causes the entrance 315 a to transition to the closed state again. After completing the acquisition of the bright data in the bright condition processing chamber 312, the control unit 33 moves the exit 315 b of the bright condition processing chamber 312 from the closed state to the open state, and then causes the image input device 100 to leave the bright condition processing chamber 312. . After leaving the image input apparatus 100 from the bright condition processing chamber 312, the control unit 333 causes the outlet 315 b of the bright condition processing chamber 312 to shift to the closed state again.

  Next, operation | movement of the calibration apparatus 1 provided with the condition setting unit 20a concerning this Embodiment is demonstrated using FIG. FIG. 15 is a flowchart for explaining the operation of the calibration apparatus 1 according to the present embodiment.

  In FIG. 15, the dark condition is realized in the dark condition processing chamber 311 (step S401). Then, the image input device 100 is disposed on the belt 321 and moves toward the dark condition processing chamber 311. When the image input device 100 is detected by the object detection sensor 322, the entrance 313a of the dark condition processing chamber 311 is opened, and the image input device 100 enters and is stored in the dark condition processing chamber 311 (step S402).

  After the image input device 100 is accommodated in the dark condition processing chamber 311, image data is acquired by the optical sensor 53 of the image input device 100, and the acquired image data is input to the input unit 11 as dark data (step) S403). After the dark data is acquired, the belt 321 operates and the image input apparatus 100 leaves the dark condition processing chamber 311 (step S404).

  Next, the bright condition is realized in the bright condition processing chamber 312 (step S405). Then, the image input device 100 moves again toward the bright condition processing chamber 312. When the image input device 100 is detected by the object detection sensor 323, the entrance 315a of the light condition processing chamber 312 is opened, and the image input device 100 enters the light condition processing chamber 312 and is stored (step S406).

  After the image input device 100 is stored in the bright condition processing chamber 312, image data is acquired by the optical sensor 53 of the image input device 100, and the acquired image data is input to the input unit 11 as bright data (step) S407). After the bright data is acquired, the belt 321 operates and the image input apparatus 100 exits from the bright condition processing chamber 312 (step S408).

  In this way, dark data and bright data are input to the input unit 11 of the calibration apparatus 1.

  Next, the analysis unit 12 of the calibration apparatus 1 acquires dark data and bright data input from the input unit 11 and performs correction for correcting image data that the image input apparatus 100 acquires by the optical sensor 53 during normal operation. Data is calculated and stored in the storage unit 13 (step S409). Then, the output unit 14 of the calibration apparatus 1 takes out the correction data from the storage unit 13 and outputs it to the image input apparatus 100 (step S410).

  The processes in steps S401 to S410 are usually performed before the image input apparatus 100 is shipped, but may be performed after the shipment.

  Note that the operation of the image input apparatus 100 that has received the correction data output from the calibration apparatus 1 is the same as that of the first embodiment, and therefore description thereof will not be repeated here.

  In each of the above embodiments, dark data and light data may be acquired after a plurality of image input devices 100 are housed in the dark condition processing chamber 311 and the light condition processing chamber 312 at a time. In that case, since dark data and bright data for a plurality of image input devices 100 can be acquired simultaneously, calibration of the plurality of image input devices 100 can be performed in a short time.

In the example of FIG. 14, the shapes of the dark condition processing chamber 311 and the light condition processing chamber 312 are represented by rectangular parallelepipeds, but are not particularly limited to this example, and a substantially cylindrical shape may be used.
(Embodiment 4)
Next, a fourth embodiment of the present invention will be described. The third embodiment is an embodiment for explaining an example in which the dark condition setting unit 21 and the bright condition setting unit 22 are realized by separate processing chambers 311 and 312.

  On the other hand, this embodiment is an embodiment for explaining an example in which the dark condition setting unit 21 and the bright condition setting unit 22 are realized using the same processing chamber. The dark condition setting unit 21 and the bright condition setting unit 22 are the same as those in the third embodiment except that the same storage box is used, and only different points will be described here.

  FIG. 16 is a configuration diagram of a condition setting unit according to the present embodiment. In the condition setting unit 20b according to the present embodiment, as shown in FIG. 16, a processing chamber 411 is installed on a belt (conveyance unit) 421 circulated by driving units (conveyance units) 431 and 432.

  The processing chamber 411 has an inlet 413a and an outlet 413b. The inlet 413a and the outlet 413b are basically closed and are opened and closed only when the image input apparatus 100 enters and exits. The entrance 413a and the exit 413b may be configured using, for example, an opening / closing door, and as a mechanism for opening / closing, there is a method of sliding the opening / closing door mechanically. Further, instead of providing such an opening / closing door, a cloth may be simply hung on the inlet 413a and the outlet 413b.

  The image input apparatus 100 is disposed on the belt 421 and passes through the inside of the processing chamber 411 by the circulation of the belt 421 by the driving units 431 and 432. An object detection sensor 422 is provided in the vicinity of the entrance 413a of the processing chamber 411, and the position of the image input device 100 approaching the processing chamber 411 is detected by the object detection sensor 422. When the image input apparatus 100 enters the processing chamber 411, the circulation of the belt 421 is stopped, and acquisition of dark data and bright data is started. As the object detection sensor 422, a photo interrupter, an ultrasonic sensor, or the like may be used.

  After the acquisition of the dark data and the bright data, the circulation of the belt 421 by the driving units 431 and 432 is started again, and the image input apparatus 100 goes out of the processing chamber 411.

  The processing chamber 411 can store the image input device 100, covers the entire image input device 100, blocks incident external light, and has a light source 412 provided therein, and the light source 412 emits light with bright illuminance. The light can be emitted. The processing chamber 411 can realize the dark condition and the bright condition in itself by switching the state of the light source 412 between lighting / extinguishing, and by doing so, the manufacturing cost of the calibration apparatus 1 can be realized. Can be reduced.

  As the light source 412 of the present embodiment, for example, an organic EL light, a panel type white LED (light emitting diode) light, or the like may be used. In FIG. 16, the light source 412 is installed on the inner surface of the processing chamber 411 facing the display panel unit 50 of the image input apparatus 100, but may be provided in the entire interior. Needless to say, it is not always necessary to provide the light source 412 on the inner surface, and the light intensity of the light emitted from the light source 412 is large, and even if it is on one of the inner surfaces of the process chamber 411, the illuminance of the entire process chamber 411 is constant. As long as it can be reduced, the installation of the light source 412 on the facing surface is not limited.

  If the light source 412 is not provided in the entire interior of the processing chamber 411, a light absorbing material may be coated in the other interior of the processing chamber 411 as in the first and second embodiments. Of course, you can simply paste black paper.

  The control unit 433 is connected to each of the drive units 431 and 432, the processing chamber 411, and the object detection sensor 422, and controls entry and exit of the image input apparatus 100 to the processing chamber 411. Specifically, when the image input device 100 is arranged on the belt 421, the control unit 433 starts driving the drive units 431 and 432 and moves the image input device 100 to the processing chamber 411 side. The object detection sensor 422 detects the position of the image input device 100, and the control unit 433 shifts the inlet 413a of the processing chamber 411 from the closed state to the open state based on the detection signal. After the image input apparatus 100 enters the processing chamber 411, the control unit 433 shifts the inlet 413a to the closed state again. After the acquisition of dark data and bright data in the processing chamber 411, the control unit 433 causes the image input apparatus 100 to exit the processing chamber 411 after shifting the outlet 413 b of the processing chamber 411 from the closed state to the open state. After leaving the image input apparatus 100 from the processing chamber 411, the control unit 433 shifts the outlet 413b of the processing chamber 411 to the closed state again.

  Next, operation | movement of the calibration apparatus 1 provided with the condition setting unit 20b concerning this Embodiment is demonstrated using FIG. FIG. 17 is a flowchart for explaining the operation of the calibration apparatus 1 according to the present embodiment.

  In FIG. 17, a dark condition is realized in the processing chamber 411 (step S501). Then, the image input device 100 is disposed on the belt 421 and moves toward the processing chamber 411. When the image input device 100 is detected by the object detection sensor 422, the inlet 413a of the processing chamber 411 is opened, and the image input device 100 enters the processing chamber 411 and is stored (step S502).

  After the image input device 100 is stored in the processing chamber 411, image data is acquired by the optical sensor 53 of the image input device 100, and the acquired image data is input to the input unit 11 as dark data (step S503). . Then, after the dark data is acquired, the bright condition is realized in the processing chamber 411 (step S504).

  Then, image data is acquired by the optical sensor 53 of the image input apparatus 100, and the acquired image data is input to the input unit 11 as bright data (step S505). After the bright data is acquired, the belt 421 operates and the image input apparatus 100 leaves the processing chamber 411 (step S506).

  In this way, dark data and bright data are input to the input unit 11 of the calibration apparatus 1.

  Next, the analysis unit 12 of the calibration apparatus 1 acquires dark data and bright data input from the input unit 11 and performs correction for correcting image data that the image input apparatus 100 acquires by the optical sensor 53 during normal operation. Data is calculated and stored in the storage unit 13 (step S507). Then, the output unit 14 of the calibration apparatus 1 takes out the correction data from the storage unit 13 and outputs it to the image input apparatus 100 (step S508).

  The processes in steps S501 to S508 are usually performed before shipment of the image input apparatus 100, but may be performed after shipment.

  Note that the operation of the image input apparatus 100 that has received the correction data output from the calibration apparatus 1 is the same as that of the first embodiment, and therefore description thereof will not be repeated here.

  In each of the above embodiments, dark data and bright data may be acquired after a plurality of image input devices 100 are accommodated in the processing chamber 411 at a time. In that case, since dark data and bright data for a plurality of image input devices 100 can be acquired simultaneously, calibration of the plurality of image input devices 100 can be performed in a short time.

  In the example of FIG. 16, the shape of the processing chamber 411 is represented by a rectangular parallelepiped, but is not particularly limited to this example, and a substantially cylindrical shape may be used.

  Finally, the calibration apparatus 1 according to each of the above embodiments may be implemented by hardware using an integrated circuit or the like, or by software using a CPU or the like.

  That is, the calibration apparatus 1 includes a CPU (central processing unit) that executes instructions of a control program that realizes each function, a ROM (read only memory) that stores the program, and a RAM (random access memory) that expands the program. And a storage device (recording medium) such as a memory for storing the program and various data. An object of the present invention is a recording medium on which a program code (execution format program, intermediate code program, source program) of a control program of the calibration apparatus 1 which is software for realizing the functions described above is recorded so as to be readable by a computer. This can also be achieved by supplying the calibration apparatus 1 and reading and executing the program code recorded on the recording medium by the computer (or CPU or MPU).

  Examples of the recording medium include a tape system such as a magnetic tape and a cassette tape, a magnetic disk such as a floppy (registered trademark) disk / hard disk, and a compact disk-ROM / MO / MD / digital video disk / compact disk-R. A disk system including an optical disk, a card system such as an IC card (including a memory card) / optical card, or a semiconductor memory system such as a mask ROM / EPROM / EEPROM / flash ROM can be used.

  Further, the calibration apparatus 1 may be configured to be connectable to a communication network, and the program code may be supplied via the communication network. The communication network is not particularly limited. For example, the Internet, intranet, extranet, LAN, ISDN, VAN, CATV communication network, virtual private network, telephone line network, mobile communication network, satellite communication A net or the like is available. Also, the transmission medium constituting the communication network is not particularly limited. For example, even in the case of wired such as IEEE 1394, USB, power line carrier, cable TV line, telephone line, ADSL line, etc., infrared rays such as IrDA and remote control, Bluetooth ( (Registered trademark), 802.11 wireless, HDR, mobile phone network, satellite line, terrestrial digital network, and the like can also be used. The present invention can also be realized in the form of a computer data signal embedded in a carrier wave in which the program code is embodied by electronic transmission.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  The present invention can also be expressed as follows. That is, the calibration method according to the present invention includes image data read by an image input device having a display unit including a transparent flat plate for displaying an image and an imaging unit for picking up a contact surface in contact with the flat plate. On the other hand, a calibration method for performing calibration, wherein the dark data is obtained under a condition that the flat plate has a constant dark illuminance by using a cover in which a material with low light reflection is attached. A dark data acquisition step for acquiring, and a bright data acquisition step for acquiring the bright data under a condition that the flat plate has a constant bright illuminance, using a cover on which a material having a large amount of light reflection is attached. And correcting the image data using the dark data and the bright data.

  It is preferable that the bright data is acquired under a condition that the flat plate has a constant bright illuminance by using a cover having a light emitter inside.

  A dark data acquisition step of acquiring the dark data under a condition that the flat plate has a constant dark illuminance while the light emitter is in a non-light-emitting state using a cover provided with a light emitter inside; and the light emitter emits light It is preferable to include a bright data acquisition step of acquiring the bright data under a condition in which the flat plate has a constant bright illuminance.

  It is preferable that the bright data is acquired under a condition where the illuminance is high enough not to saturate the pixels constituting the image data read by the image input step.

  A calibration program according to the present invention is a calibration program for causing a computer to execute the above calibration method.

  A computer-readable recording medium according to the present invention is a machine-readable recording medium that records a calibration program for causing a computer to execute the calibration method described above.

  A calibration apparatus according to the present invention is configured to perform image data read by an image input apparatus having a display unit including a transparent flat plate for displaying an image and an imaging unit for imaging a contact surface in contact with the flat plate. A calibration apparatus for performing calibration, wherein the dark data is acquired under a condition in which the flat plate has a constant dark illuminance by using a cover on which a material with low light reflection is attached. A dark data acquisition means and a bright data acquisition means for acquiring the bright data under a condition where the flat plate has a constant bright illuminance using a cover on which a material having a large amount of light reflection is attached. The image data is corrected using the dark data and the bright data.

  The covering preferably has a box shape.

  The bottom surface of the cover is preferably larger than the display area of the display unit.

  The present invention can be applied to devices such as PCs, PDAs, and mobile phones.

It is a block diagram which shows the structure of the calibration apparatus concerning Embodiment 1 of this invention. 1 is a block diagram illustrating a schematic configuration of an image input apparatus that is calibrated by a calibration apparatus according to a first embodiment of the present invention; FIG. 3 is an overall view of the image input apparatus in FIG. 2. It is a figure for demonstrating the specific example of the dark condition setting part of FIG. It is a figure for demonstrating the specific example of the bright condition setting part of FIG. It is a flowchart which shows the process sequence of the calibration method concerning Embodiment 1 of this invention (the 1). It is a figure for demonstrating step S101 and step S102 of FIG. It is a figure for demonstrating step S103 and step S104 of FIG. It is a figure for demonstrating step S105 of FIG. It is a flowchart which shows the process sequence of the calibration method concerning Embodiment 1 of this invention (the 2). It is a figure for demonstrating step S203 of FIG. It is a figure for demonstrating the specific example of the dark condition setting part of Embodiment 2 of this invention, and a bright condition setting part. It is a flowchart which shows the process sequence of the calibration method concerning Embodiment 2 of this invention. It is a block diagram of the condition setting unit concerning Embodiment 3 of this invention. It is a flowchart which shows the process sequence of the calibration method concerning Embodiment 3 of this invention. It is a block diagram of the condition setting unit concerning Embodiment 4 of this invention. It is a flowchart which shows the process sequence of the calibration method concerning Embodiment 4 of this invention. (A) is sectional drawing which shows schematic structure of the display panel part of the conventional image input device, (b) is an enlarged view of the A section of (a). (A) is a figure which shows the mode of the path | route of the light radiate | emitted from the light source of FIG. 18, (b) is a schematic diagram which shows the brightness of the display surface of (a), (c) is a figure of (b). It is a graph which shows the brightness of B area | region. It is a figure which shows the mode of the image obtained from the optical sensor of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Calibration apparatus 10 Calibration unit 11 Input part (input means)
12 Analysis unit (analysis means)
13 storage unit 14 output unit 20, 20a, 20b condition setting unit 21 dark condition setting unit (first illuminance setting unit)
22 Bright condition setting section (second illuminance setting section)
DESCRIPTION OF SYMBOLS 50 Display panel part 51 Display surface 52 Transparent protective layer 53 Optical sensor 53a Optical sensor element 54 Light shielding layer 54a Opening part 55 Liquid crystal substrate 56, 213, 222, 314, 412 Light source 57 Case 100 Image input device 101 Display part 102 Imaging part 103 CPU
104 Memory 211, 212, 221 Storage box 311, 312, 411 Processing chamber 313a, 315a, 413a Inlet 313b, 315b, 413b Outlet 321, 421 Belt (conveyance unit)
322, 323, 422 Object detection sensor 331, 332, 431, 432 Drive unit (conveyance unit)
333, 433 control unit

Claims (12)

A calibration device for correcting image data read by an image input device having an imaging unit including a plurality of photosensor elements,
First image data read by the image input device in a first space where light having a first illuminance is uniformly incident on the plurality of photosensor elements, and a second illuminance brighter than the first illuminance. Input means for inputting second image data read by the image input device in a second space where light is uniformly incident on the plurality of photosensor elements;
Correction data for correcting the first and second image data input by the input unit and correcting image data read when the image input device images the imaging object based on the analysis result A calibration apparatus comprising: an analyzing means for generating   In the first and second spaces, the image input device further includes a condition setting unit that defines the first and second spaces around the image input device so that the image data can be read by the image input device. The calibration apparatus according to claim 1, wherein: The condition setting unit includes a first illuminance setting unit that defines the first space, and a second illuminance setting unit that defines the second space,
The first illuminance setting unit is configured from a first storage box that stores the image input device and delimits the first space by preventing external light from entering the image input device. And
The second illuminance setting unit includes a second storage box that stores the image input device and a light source provided inside the second storage box, and is stored in the second storage box. The calibration device according to claim 2, wherein the second space is defined by irradiating the image input device with light emitted from the light source. The condition setting unit includes a storage box that stores the image input device, and a light source provided inside the storage box.
The condition setting unit stores the image input device in the storage box and prevents the external light from entering the image input device, thereby defining the first space and storing the image input device in the storage box. The calibration device according to claim 2, wherein the second space is defined by irradiating the image input device with light emitted from the light source. The image input device has an imaging unit arrangement surface on which the imaging unit is arranged,
The storage box has an inner surface that faces the imaging unit arrangement surface of the image input device when the storage box itself stores the image input device and has an area larger than the imaging unit arrangement surface. The calibration device according to claim 3 or 4. The condition setting unit includes a first illuminance setting unit that defines the first space, and a second illuminance setting unit that defines the second space,
The first illuminance setting unit is configured from a first processing chamber that houses the image input device and delimits the first space by preventing external light from entering the image input device. And
The second illuminance setting unit includes a second processing chamber in which the image input device is stored, and a light source provided in the second processing chamber, and is stored in the second processing chamber. The second space is defined by irradiating the image input device with light emitted from the light source,
The condition setting unit further includes a transport unit that transports the image input device so that the image input device is sequentially accommodated in the first and second processing chambers. The calibration device according to claim 2. The condition setting unit includes a processing chamber for storing the image input device, a light source provided in the processing chamber, and the image input device so that the image input device is stored in the processing chamber. And a conveyance unit that conveys
The condition setting unit defines the first space by storing the image input device in the processing chamber by the transport unit and preventing external light from entering the image input device. The calibration device according to claim 2, wherein the second space is defined by irradiating the image input device housed in a processing chamber with light emitted from the light source. The imaging unit of the image input device includes the plurality of optical sensor elements that convert the illuminance of incident light into an electrical signal having a voltage value corresponding to the illuminance.
The calibration apparatus according to claim 1, wherein the second illuminance is less than the illuminance of incident light at which an electrical signal output from the optical sensor element is saturated. The imaging unit of the image input device includes the plurality of optical sensor elements that convert the illuminance of incident light into an electrical signal having a voltage value corresponding to the illuminance.
The analyzing means acquires an output value of the photosensor element according to the first illuminance and an output value of the photosensor element according to the second illuminance for each of the plurality of photosensor elements, 9. The offset value and gain value in the conversion by the optical sensor element are calculated based on the two output values, and the offset value and gain value are generated as the correction data. The calibration apparatus according to item 1.   A calibration program for operating a computer as each of the means in the calibration apparatus according to claim 1.   The computer-readable recording medium which recorded the calibration program of Claim 10. A calibration method for correcting image data read by an image input device having an imaging unit including a plurality of photosensor elements,
First image data read by the image input device in a first space where light having a first illuminance is uniformly incident on the plurality of photosensor elements, and a second illuminance brighter than the first illuminance. An input step for inputting second image data read by the image input device in a second space where light is uniformly incident on the plurality of photosensor elements;
The first and second image data input in the input step is analyzed, and a correction for correcting image data read when the image input device images the imaging object based on the analysis result An analysis step to generate data;
And a correction step of correcting image data read by the image input device based on the correction data generated in the analysis step when the image input device images an imaging target. Calibration method.

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