JP2011210057A - Scanner device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a scanner device which easily obtains a reading signal to be used as a reference.SOLUTION: The scanner device includes a light source 12, an imaging device 15 and a first optical system 13 which are provided in a casing 11, wherein, when a scanning object S is irradiated with light from the light source 12, the scanning object S being placed at a reading position P set to be in predetermined relationship with the casing 11, the reflected light of the irradiation light is led to the imaging device 15 via the first optical system 13, and image reading of the scanning object based on an output signal from the imaging device 15 is performed. The scanner device is constituted in such a way that: a color reference plate 16 is provided at a position where the light from the light source 12 in the casing 11 reaches; and there are provided in the casing 11 a second optical system 17 which leads the reflected light on the color reference plate 16 of the light from the light source 12 to the imaging device 15, and a switching mechanism 18 which switches a state of preventing the reflected light on the color reference plate 16 from being led to the imaging device 15 via the second optical system 17 and a state of releasing the prevention.

Description

  The present invention relates to a scanner device that optically scans a scan target and obtains image information from the surface of the scan target.

  For example, a scanner device is used as a barcode verification machine for verifying the suitability of a barcode printed on a label (see Patent Document 1). In this barcode verification machine, a label printed with a barcode as a scan object is scanned with light from a light source, and reflected light from the label obtained at that time is incident on an image sensor (for example, CCD). It has become. Then, the suitability of the barcode printed on the label is determined based on a read signal corresponding to the density of the barcode output from the imaging device on which the reflected light is incident.

  The bar code verifier further has a known reflectance (concentration) in order to prevent the verification accuracy from deteriorating due to illuminance unevenness of the light source, aging change of irradiation light intensity, aging change of the image sensor, etc. The read signal output from the image sensor is corrected using the white and black color reference plates. Specifically, the level of the output signal (read signal) from the image sensor when the reflected light from the white and black color reference plates irradiated with light from the light source is received by the image sensor is white and black. As a reference, the level of the output signal from the image sensor when the reflected light from the label printed with the actual barcode is received is corrected.

  According to such a bar code verifier (scanner device), even if the illuminance unevenness of the light source, the secular change of the irradiation light, or the secular change of the image sensor occurs, a signal obtained by correcting the output signal from the image sensor Always represents relative shading relative to white and black of the white reference plate and the black reference plate, so that the verification accuracy can be prevented from being lowered.

Japanese Patent Laid-Open No. 08-96060

  However, in the scanner device having the correction function as described above, in order to obtain the read signal level of the color reference plate such as the white reference plate or the black reference plate as a reference value, the color reference plate is separately prepared and the reading position is prepared. The operation is troublesome because it has to be set to the position. For example, in a scanner device that optically scans each of a number of scan objects continuously conveyed by a conveyance mechanism, the conveyance of the scan object is stopped or the scan object is removed from the conveyance path. After that, the color reference plate must be set at the reading position, which is particularly troublesome and hinders efficient scanning operation.

  The present invention has been made in view of such circumstances, and provides a scanner device that can easily obtain a reference read signal.

  The scanner device according to the present invention includes a light source, an image sensor, and a first optical system in a housing, and light from the light source is applied to a scan target at a reading position set at a position having a predetermined relationship with the housing. A scanner device that, when irradiated, causes reflected light to be guided to the image sensor via the first optical system, and reads an image of the scan object based on an output signal from the image sensor. A color reference plate is provided at a position where light from the light source reaches within the housing, and a second optical system that guides reflected light of the light from the light source on the color reference plate to the imaging device; A switching mechanism for switching between a state of preventing reflected light from the color reference plate from being guided to the image pickup device via the second optical system and a state of releasing the blocking is provided in the housing. Become

  With such a configuration, the light reflected from the light source on the color reference plate in the state where the light reflected on the color reference plate is prevented from being guided to the image sensor via the second optical system. Without reaching the image sensor, the light from the light source is reflected by the scanning object at the reading position, and the reflected light is guided to the image sensor via the first optical system. In this case, an image of the scan target can be read based on the output signal from the image sensor.

  In a state where there is no scan object at the reading position, the switching mechanism prevents the reflected light from the color reference plate of the light from the light source from being guided to the image sensor via the second optical system, When the state is switched to the state where the blocking is released, the reflected light of the light from the light source on the color reference plate is guided to the image sensor through the second optical system. In this case, the image of the color reference plate is read based on the output signal from the image sensor, and the color density reference can be obtained based on the color density of the read image of the color reference plate.

  The scanner device according to the present invention may include a transport mechanism that transports the scan target so as to pass through the reading position.

  With such a configuration, in a state where the reflected light from the light source on the color reference plate is prevented from being guided to the image pickup device via the second optical system, the scanning object transported by the transport mechanism is the reading position. The image of the scanned object can be read as it passes through.

  In the scanning device according to the present invention, the second optical system includes a mirror, and the switching mechanism is configured to guide the angle of the mirror in a direction in which reflected light from the color reference plate is deviated from the imaging element. It can be set as the structure which has the mirror rotation mechanism which rotates between an angle and the 2nd angle by which the said reflected light is guide | induced to the said image pick-up element.

  With this configuration, when the mirror of the second optical system has the first angle, the reflected light of the light from the light source on the color reference plate does not reach the image sensor, while the mirror is switched to the second angle. Then, the light reflected from the color reference plate of the light from the light source is guided to the image sensor.

  Further, in the scanning device according to the present invention, the first angle is such that the mirror guides the reflected light from the reference plate in a direction away from the image sensor and reflects the light from the light source to the reading position. It can be set as the structure which is the angle led.

  With this configuration, when the mirror of the second optical system is at the first angle, the reflected light of the light from the light source on the color reference plate does not reach the image sensor, and the light from the light source is not reflected on the mirror. Since the reflected light is guided to the reading position, the light from the light source is guided to the scanning object at the reading position via the first optical system and other light from the light source. Is guided through the mirror of the second optical system. Therefore, the light from the light source can be used effectively by illuminating the scan target.

  In the scanning device according to the present invention, the switching mechanism may include a shutter mechanism that switches between blocking and passage of light traveling to the imaging element via the second optical system.

  With such a configuration, the light that travels to the image sensor via the second optical system is blocked or passes by the shutter mechanism, so that the reflected light from the color reflection plate is prevented from being guided to the image sensor and the light block is prevented. Can be switched.

  Further, in the scanning apparatus according to the present invention, the transport mechanism includes a support plate that movably supports the scan object, and a moving mechanism that moves the scan object on the support plate, A gap that allows light from the light source of the scanner unit to pass through may be formed in a predetermined region including the reading position of the plate.

  With such a configuration, the light traveling from the light source to the reading position passes through the gap of the support plate in a state where the light reflected from the color reference plate of the light source is guided to the image sensor through the second optical system. Therefore, the light traveling from the light source to the reading position can be prevented as much as possible from entering the image sensor as stray light in the apparatus.

  According to the scanning device of the present invention, the color reference plate is provided in the housing of the scanner unit without separately preparing a color reference plate and setting it at the reading position as in the prior art. Since the reflected light from the color reference plate can be guided to the image sensor, a reference read signal can be easily obtained using the color reference plate.

It is a figure which shows the structure of the mechanism part of the barcode verification machine to which the scanner apparatus which concerns on one Embodiment of this invention was applied. It is a figure which shows the structural example (state at the time of reading a scanning target object) of a scanner unit. It is a figure which shows the state of the scanner unit at the time of reading a color reference board. It is a block diagram which shows the structural example of the control part of a barcode verification machine. It is a figure which shows the waveform example of CCD which the reflected light in a color reference board injects, and its output signal. It is a figure which shows the other structural example (state at the time of reading a scanning target object) of a scanner unit. It is a figure which shows the state of the scanner unit at the time of reading a color reference board.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  A mechanism unit of a bar code verifier to which a scanner device according to an embodiment of the present invention is applied is configured as shown in FIG.

  In FIG. 1, a scanner unit 10, a transport mechanism 20, and a stamper 30 are provided in the device casing 110 of the barcode verifier 100. The transport mechanism 20 has a motor 21 as a drive source, and is driven by a drive pulley 22 fixed to the rotating shaft of the motor 21, and a first driven pulley 23a, a second driven pulley 23b, and a third driven pulley 23c. A timing belt 24 is wound around the pulley, and the rotation of the driving pulley 22 that is rotated by driving the motor 21 is transmitted to the three driven pulleys 23a, 23b, and 23c via the timing belt 24. Further, the transport mechanism 20 includes a support plate 28 extending from the inlet IN to the outlet OUT of the device housing 110, and the first transport roller group 25 a, the second transport roller group 25 b, and the third transport axis 20 along the support plate 28. A transport roller group 25c is arranged. Each of the three transport roller groups 25a, 25b, and 25c is connected to a corresponding driven roller of the three driven rollers 23a, 23b, and 23c by a belt or the like, and each transport roller 23a, 23b, and 23c is transported by rotation of each driven roller 23a, 23b, and 23c The roller groups 25a, 25b, and 25c are configured to rotate.

  A stage 111 and a side guide 112 are provided outside the entrance IN of the device casing 110, and a sheet S on which barcode printed labels discharged from the printer 200 are arranged is placed by the stage 111 and the side guide 112. It is supplied on the support plate 28 from the inlet IN while being guided. The sheet S supplied to the support plate 28 is transported on the support plate 28 by the first transport roller 25a, the second transport roller 25b, and the third transport roller 25c, and is discharged from the outlet OUT.

  The scanner unit 10 is disposed at a predetermined position in the device casing 110 so as to face the support plate 28 of the transport mechanism 20. Specifically, the scanner unit 10 is configured as shown in FIGS. 2 and 3, for example, a light source 12, a half mirror 13 (first optical system), a lens system 14, and a one-dimensional CCD 15 (imaging device) having a configuration in which a plurality of LEDs are arranged in a housing 11. Is provided. An opening 11 a is formed at a predetermined portion of the housing 11 that faces the support plate 28. The light source 12, the half mirror 13, the lens system 14, and the CCD 15 receive light from the light source 12 on a sheet S (label) that passes through a reading position P set at a position on the support plate 11 that has a predetermined relationship with the housing 11. When irradiated through the opening 11 a of the housing 11, the reflected light from the sheet S that enters the housing 11 through the opening 11 a is guided to the CCD 15 through the half mirror 13 and the lens system 14. Have been placed.

  In addition, a white and black color reference plate 16 and a mirror 17 (second optical system) are provided in the housing 11. The mirror 17 is disposed on the opposite side of the CCD 15 of the half mirror 13. The color reference plate 16 is disposed at a position where the light from the light source 12 can reach, and the reflected light of the light from the light source 12 on the color reference plate 16 reaches the mirror 17. The mirror 17 can be rotated between a first angle shown in FIG. 2 and a second angle shown in FIG. 3 by an actuator 18 (for example, a rotary solenoid). In the state where the mirror 17 is at the first angle (see FIG. 2), the reflected light from the color reference plate 16 illuminated by the light from the light source 12 is reflected by the mirror 17 and guided away from the CCD 15. Further, light directly incident on the mirror 17 from the light source 12 is reflected by the mirror 17 and guided to the reading position P. When the mirror 17 is at the second angle (see FIG. 3), the reflected light from the color reference plate 16 illuminated by the light from the light source 12 is reflected by the mirror 17 and passes through the half mirror 13. The light is guided to the CCD 15 through the lens system 14.

  A gap 28 a is formed in a predetermined area including the reading position P of the support plate 28 in the transport mechanism 20. When the sheet S to be scanned is present at the reading position P of the support plate 28, the gap 28a is covered by the sheet S and the light from the scanner unit 12 is reflected by the sheet S as shown in FIG. . On the other hand, when there is no sheet S at the reading position P of the support plate 28, the light from the scanner unit 12 passes through the gap 28a as shown in FIG.

  The color reference plate 16 has a structure in which black and white regions having known color densities are alternately arranged at predetermined intervals. The stamper 30 is provided adjacent to the scanner unit 10 and is used to put a predetermined mark on a label on which the printed barcode is determined to be defective. Further, an operation panel 120 is provided on the front surface of the device casing 110.

  The control unit of the bar code verifier 100 having the mechanism unit having such a structure is configured as shown in FIG.

  4, the control unit 50 includes a CPU (processing unit) 51, a ROM 52, a RAM 53, a flash memory 54, IF (interface circuits) 55a and 55b, a transport control circuit 56, input circuits 57a and 57b, and drive circuits 58a and 58b. It is configured to be connected to the bus. The conveyance control circuit 56 performs drive control of the motor 21 (see FIG. 1) of the conveyance mechanism 20 in accordance with an instruction from the CPU 51. The input circuit 57a is a sheet S on which a pulse signal is conveyed from an encoder 26 (not shown in FIG. 1) provided coaxially with one of the three conveyance roller groups 25a, 25b, and 25c of the conveyance mechanism 20. Input as a signal indicating the position of (label). The input circuit 57b inputs an output signal (read signal) from the CCD 15 as a read signal. The drive circuit 58a drives the actuator 18 according to an instruction from the CPU 51 so that the mirror 17 is at the first angle (see FIG. 2) or the second angle (see FIG. 3). The drive circuit 58b drives the stamper 30 in accordance with an instruction from the CPU 51.

  The ROM 52, the RAM 53, and the flash memory 54 store programs to be executed by the CPU 51 and various information obtained in the course of processing. The operation unit 121 and the display unit 122 provided on the operation panel 120 (see FIG. 1) are connected to the bus via the IF 55b, and various information is displayed on the display unit 122 under the control of the CPU 51. The operation information according to the operation on the operation unit 121 is taken into the CPU 51 through the IF 55b. An external PC (computer) 300 is connected to the IF 55a, and the control unit 50 can transmit / receive information to / from the external PC 300.

  The barcode verification machine 100 as described above operates, for example, as follows.

  If an operation for taking in a reference reading signal is performed in the operation unit 121 before the barcode is printed on each label on the sheet S in the printer 200, the drive circuit 58a is operated in accordance with an instruction from the CPU 51. The actuator 18 is operated to switch the mirror 17 of the scanner unit 10 to the second angle as shown in FIG. At this time, the sheet S does not exist on the support plate 28 in the barcode verification machine 100.

  In this state, the reflected light from the color reference plate 16 illuminated by the light from the light source 12 is reflected by the mirror 17 and guided to the CCD 15 through the half mirror 13 and the lens system 14. Thereby, for example, as shown in FIG. 5, white and black images of the color reference plate 16 are projected onto the linear CCD 15, and projected from each light receiving element (for example, 1024 elements) constituting the CCD 15. A level signal corresponding to the monochrome image to be output is output. At this time, the light traveling from the light source 12 through the opening 11a of the housing 11 toward the reading position P passes through the gap 28a of the support plate 28, so that the light traveling from the light source 12 toward the reading position P is It is possible to prevent the stray light from entering the CCD 15 of the scanner unit 10 as much as possible in the device casing 110.

  The input circuit 57 b receives output signals from the light receiving elements of the CCD 15, and the output signal level from each light receiving element is stored in the flash memory 54. Then, for example, the CPU 51 calculates the average value of the signal level corresponding to white stored in the flash memory 54 as the white level average value Avw, and sets the average value of the signal level corresponding to black as the black level average value Avb. Calculate. The white level average value Avw is stored in the flash memory 54 as a white reference, and the black level average value Avb is stored as a black reference.

  For example, the CPU 51 determines that the difference between the white level average value Avw and the black level average value Avb stored in the flash memory 54 in the previous time and the white level average value Avw and black level average value Avb acquired this time is a predetermined value (for example, 10%), the CPU 51 causes the display unit 122 to display an alarm message that the optical system needs to be adjusted. As a result, the operator can adjust the illuminance of light from the light source 12 and adjust the sensitivity of the CCD 15. Further, for example, when the difference between the white level average value Avw and the black level average value Avb acquired this time is smaller than a predetermined value, a message indicating that the CCD 15 has deteriorated may be displayed on the display unit 122. it can.

  Next, when printing of the barcode on each label in the printer 200 is started and the operation of starting the verification process is performed in the operation unit 121 of the barcode verification machine 100, the drive circuit is in accordance with the instruction of the CPU 51. 58a operates the actuator 18 to switch the mirror 17 of the scanner unit 10 to the first angle as shown in FIG. In this state, the printer 200 prints a barcode on each label on the sheet S, and the sheet S on which the barcode-printed labels are arranged is supplied from the printer 200 to the barcode verification machine 100. The sheet S supplied to the bar code verifier 100 enters the apparatus housing 110 from the entrance IN, and is sequentially conveyed by the respective conveyance roller groups 25a, 25b, and 25c while being supported by the support plate 28.

  In the process, as shown in FIG. 2, when the label of the sheet S (scan target) passes through the reading position P, the light from the light source 12 of the scanner unit 10 is reflected by the label at the reading position P. The reflected light is reflected by the half mirror 13 and guided to the CCD 15 through the lens system 14. At this time, the light directly incident on the mirror 17 from the light source 12 is also reflected by the mirror 17 and guided to the reading position P, so that the light from the light source 12 is effectively utilized by label illumination.

  The CPU 51 is output from each light receiving element of the CCD 15 at the timing when the reflected light from the barcode printed on the label enters the CCD 15 in synchronization with the pulse signal from the encoder 26 input by the input circuit 57a. The signal is captured as a read signal. This read signal is stored in the RAM 53 as bar code read image information. The CPU 51 determines the suitability of the barcode printed on the label based on the read image information of the barcode stored in the RAM 53 according to a predetermined algorithm. The stamper 30 attaches a predetermined mark to a label printed with a bar code that is not appropriate (unclear, misprinted, printed, etc.) under the control of the CPU 51. In this way, the barcode printed on each label on the sheet S is verified.

  As described above, the white and black determination criteria can be corrected based on the white level average value Avw and the black level average value Avb obtained from the color reference plate 16. Then, the suitability of the barcode read image based on the output signal from each light receiving element of the CCD 15 can be determined according to the predetermined algorithm using the corrected determination criterion.

  According to the scanner device (scanner unit 10 and transport mechanism 20) provided in the barcode verification apparatus 100 as described above, a color reference plate is not separately prepared and set at the reading position P as in the prior art. In addition, since the color reference plate 16 is provided in the housing 11 of the scanner unit 10 and light reflected from the color reference plate 16 of the light from the light source 12 can be guided to the CCD 15, the color reference plate. 15 can be used to easily obtain a reference read signal.

  In the scanner unit 10 described above, the angle of the mirror 17 (second optical system) is changed by the actuator 18 to prevent the reflected light from the color reference plate 16 from being guided to the CCD 15 via the mirror 17 ( 2) and a state (see FIG. 3) in which the blocking is released, the switching mechanism is not limited to the mechanism using the actuator 18. For example, as shown in FIGS. 6 and 7, a liquid crystal shutter 19 can be provided on the reflection surface of the mirror 17. In this case, when the liquid crystal shutter 19 is in a non-transmissive state as shown in FIG. 6, the reflected light from the color reference plate 16 illuminated by the light from the light source 12 is blocked by the liquid crystal shutter 19 and does not reach the mirror 17. . Accordingly, only the reflected light from the sheet S (label) at the reading position P is reflected by the half mirror 13 and guided to the CCD 15 via the lens system 14. On the other hand, when the liquid crystal shutter 19 is in the transmissive state as shown in FIG. 7, the reflected light from the color reference plate 16 illuminated by the light from the light source 12 reaches the mirror 17 via the liquid crystal shutter 19, and the mirror 17. The reflected light passes through the half mirror 13 and is guided to the CCD 15 via the lens system 14. In this state, a reference read signal can be captured.

  The scanner unit 10 described above is provided with a color reference plate 16 in which white and black regions are alternately arranged. However, other color sets, for example, colors having a complementary color relationship such as red and blue, etc. Or a set of the color and white of the image to be scanned can also be used as the color of the color reference plate 16 (reference color). Furthermore, a reference plate for one color (for example, white) and a reference plate for another color (for example, black) can be provided separately. In this case, two systems of optical systems for guiding the reflected light from the reference plate of one color and the reference plate of the other color to the CCD 15 may be provided.

  Further, the present invention can also be applied to a handy type scanner as disclosed in Patent Document 1.

  As described above, the scanner device according to the present invention has an effect that a read signal serving as a reference can be easily obtained, and an image is scanned from the surface of the scan object by optically scanning the scan object. It is useful as a scanner device for obtaining information.

DESCRIPTION OF SYMBOLS 10 Scanner unit 11 Case 11a Opening 12 Light source 13 Half mirror (1st optical system)
14 Lens system 15 CCD (Image sensor)
16 color reference plate 17 Mirror (second optical system)
DESCRIPTION OF SYMBOLS 18 Actuator 19 Liquid crystal shutter 20 Conveying mechanism 21 Motor 22 Drive pulley 23a 1st driven pulley, 23b 2nd driven pulley, 23c 3rd driven pulley 24 Timing belt 25a 1st conveying roller group, 25b 2nd conveying roller group, 25c 3rd Conveying roller group 26 Encoder 28 Support plate 28a Air gap

Claims (6)

A light source, an image sensor, and a first optical system are provided in the housing, and when the light from the light source is irradiated to the scanning object at the reading position set at a position having a predetermined relationship with the housing, the reflection A scanner device that reads light into the image sensor through the first optical system and reads an image of the scan object based on an output signal from the image sensor,
A color reference plate is provided at a position where light from the light source reaches in the housing,
A second optical system for guiding reflected light from the light source on the color reference plate to the image sensor;
A switching mechanism for switching between a state in which reflected light from the color reference plate is guided to the image sensor through the second optical system and a state in which the blocking is released is provided in the housing. Scanner device.   The scanner device according to claim 1, further comprising a transport mechanism that transports the scan object so as to pass through the reading position. The second optical system includes a mirror,
The switching mechanism has an angle of the mirror between a first angle at which reflected light from the color reference plate is guided in a direction away from the image sensor and a second angle at which the reflected light is guided to the image sensor. The scanner device according to claim 1, further comprising a mirror rotation mechanism that is rotated at the same time.   4. The scanner according to claim 3, wherein the first angle is an angle at which the mirror guides reflected light from the reference plate in a direction away from the image sensor and reflects light from the light source to guide the reading position. 5. apparatus.   3. The scanner device according to claim 1, wherein the switching mechanism includes a shutter mechanism that switches between blocking and passage of light traveling to the imaging element via the second optical system. The transport mechanism includes a support plate that movably supports the scan object;
A moving mechanism for moving the scan object on the support plate,
The scanner device according to claim 2, wherein a gap for allowing light from the light source of the scanner unit to pass through is formed in a predetermined region including the reading position of the support plate.

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