JP4973308B2 - Optical information reader - Google Patents

Description

  The present invention relates to an optical information reader.

2. Description of the Related Art Conventionally, as an optical information reading device that reads an identification code such as a bar code, a configuration in which reflected light from the identification code is read by a light receiving sensor in which light receiving elements are arranged is provided. For example, in Patent Document 1, a barcode is divided into a plurality of regions, a reading operation is performed for each region, and a plurality of data obtained by the plurality of reading operations are combined to read the entire barcode. I am doing so. According to such a technique, reading can be suitably performed even if the barcode is wide.
Japanese Patent Laid-Open No. 4-111083

  In the case of the configuration of Patent Document 1, although it is possible to read a wide barcode, it is necessary to perform a plurality of reading operations on one barcode, which takes time and effort. There's a problem. On the other hand, as a method for reducing labor and time, a method of enlarging the light receiving sensor to such an extent as to cover the entire wide barcode is conceivable. However, such a large light receiving sensor is disadvantageous in terms of cost and the like.

  The present invention has been made to solve the above-described problems, and provides an optical information reader capable of quickly reading a long barcode with high resolution and excellent in operability and cost. For the purpose.

In order to achieve the above object, the invention according to claim 1 is a light receiving sensor comprising a line sensor in which light receiving elements are arranged, illumination means for irradiating illumination light to an identification code comprising a longitudinal bar code, and the illumination Illumination control means for controlling the means, exposure control means for controlling exposure of the light receiving sensor, image forming means for forming an image of the identification code, and image data of the identification code output from the light receiving sensor. An optical information reader comprising: storage means for storing; and decoding means for decoding the identification code based on the image data stored in the storage means, wherein the illuminating means First illumination means for irradiating a first region in the longitudinal direction, and second illumination means for irradiating a second region shifted in the longitudinal direction from the first region of the identification code, The image forming means includes a first image forming means for forming an image on the first area side of the identification code over a majority area of the light receiving sensor, and a part of the image on the first area side. Second image forming means for forming an image on the second area side over a majority area of the light receiving sensor, and the illumination control means moves the illumination means to the second area more than the second area. It is possible to change the setting between a first illumination state that illuminates one area brightly and a second illumination state that illuminates the second area brighter than the first area. When the first illumination state is set, the first image data formed by forming an image on the first region side is output to the light receiving sensor, and when the second illumination state is set, The second image data formed by forming an image on the second region side is received. The storage unit stores the first image data and the second image data output from the light receiving sensor, and the decoding unit stores the first image data stored in the storage unit. Based on the overlapping portion of the image data and the second image data, synthesized decoded data is generated by synthesizing and decoding the first image data and the second image data.

The invention of claim 2 is the optical information reader according to claim 1 , wherein the identification code is a bar code, and the first illumination means irradiates a region on one side in the longitudinal direction of the bar code, The second illuminating unit is configured to irradiate a region opposite to the one side, and the exposure control unit is configured such that when the illuminating unit is set to the first illumination state, The second image formed by forming the image on the opposite side when the first image data formed by forming the image on one side is output to the light receiving sensor and the second illumination state is set. The image data is output to the light receiving sensor.

According to a third aspect of the present invention, in the optical information reading device according to the first or second aspect , in the first illumination state, the illumination control unit turns on the illumination of the first illumination unit and The first illumination unit and the second illumination unit are configured to turn off the illumination of the second illumination unit and turn off the illumination of the first illumination unit and turn on the illumination of the second illumination unit in the second illumination state. It is characterized by controlling.

  According to the first aspect of the present invention, the first image forming means for forming the image on the first region side of the identification code over the majority region of the light receiving sensor, and the second region partially overlapping with the image on the first region side A second image forming means for forming an image on the side over the majority region of the light receiving sensor, and when the illumination means is set to the first illumination state, the image on the first area side is formed. The first image data is output to the light receiving sensor, and when the second illumination state is set, the second image data formed by forming an image on the second region side is output to the light receiving sensor. Therefore, the images of the two areas in the identification code can be quickly acquired without complicated operations. Further, since the composite decoded data is generated by synthesizing and decoding the first image data and the second image data based on the overlapping part of the first image data and the second image data, a long barcode is high. It can be read well with resolution. In addition, according to this configuration, a long bar code can be satisfactorily read without increasing the size of the light receiving sensor, so that the configuration is excellent in terms of cost.

In the invention of claim 2 , the first illumination means irradiates a region on one side in the longitudinal direction of the barcode, and the second illumination means irradiates a region opposite to one side (irradiation side by the first illumination means). When configured to irradiate and set to the first illumination state, the first image data formed by forming an image on one side of the barcode is output to the light receiving sensor and set to the second illumination state. Sometimes, the second image data formed by forming the image on the opposite side is output to the light receiving sensor. According to this configuration, a barcode that tends to be long can be divided into two regions and read well with high resolution, and the reading operation can be simplified and speeded up.

In the invention of claim 3 , in the first illumination state, the illumination of the first illumination unit is turned on and the illumination of the second illumination unit is turned off. In the second illumination state, the illumination of the first illumination unit is turned off and the second illumination unit is turned off. The first illumination means and the second illumination means are controlled to turn on the illumination of the two illumination means. Therefore, when the image on the first area side is read, the influence of the second illumination means can be eliminated, and the image on the first area side can be read with high accuracy and good. Similarly, when the image on the second area side is read, the influence of the first illumination means can be eliminated, so that the image on the second area side can be read with high accuracy and good. Furthermore, since the illumination means that illuminates the side that is not the reading side (for example, the second illumination means that illuminates the side that is not the reading side when reading the first region side) is turned off, power saving can be achieved. It becomes composition.

[First embodiment]
DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, a first embodiment in which an optical information reading device of the invention is embodied will be described with reference to the drawings. FIG. 1 is a block diagram schematically showing an electrical configuration of a barcode reader 1 according to the first embodiment of the optical information reading apparatus of the present invention. FIG. 2 is an explanatory diagram for explaining illumination means and image forming means in the barcode reader 1 of FIG. 2 is a view of a long barcode B to be read as viewed in a direction perpendicular to the reading surface (the surface to which the barcode B is attached in the reading object R (FIG. 1)). 2 is a view of the barcode B, the illumination means, and the imaging means as viewed in the direction along the reading surface. FIG. 3 is a flowchart illustrating a flow of reading process control in the barcode reader 1. FIG. 4 is a timing chart for explaining illumination timing, exposure timing, and image capture timing. FIG. 5 is an explanatory diagram illustrating an image on the first area side, an image on the second area side, and the like. FIG. 6 is an explanatory diagram for explaining the generation of the composite decoded data.

  The bar code reader 1 corresponds to an example of an “optical information reading device”, and includes the circuit unit 20 shown in FIG. 1 in a case (not shown), and is provided in the case. Illumination light Lf1, Lf2 (described later) is derived from a reading port (not shown), and reflected light Lr1, Lr2 from the barcode B (barcode B corresponds to an example of “identification code”) is received by the light receiving sensor 28. The information of the barcode B is read based on the obtained image data.

  As shown in FIG. 1, the circuit unit 20 includes an optical system such as a first illumination light source 21, a second illumination light source 22, a light receiving sensor 28, a first imaging lens 26, a second imaging lens 27, a memory 35, It is composed of a microcomputer system (hereinafter referred to as “microcomputer”) such as a control circuit 40 and operation switch 50, and a power supply system including a power supply circuit (not shown).

The optical system is divided into a light projecting optical system and a light receiving optical system.
As shown in FIGS. 1 and 2, the first illumination light source 21 and the second illumination light source 22 constituting the light projecting optical system can emit illumination lights Lf1 and Lf2, respectively, and both are “illuminating means”. Function as. The first illumination light source 21 corresponds to an example of “first illumination means”, and is a first region in the longitudinal direction of the barcode B (a region irradiated by the first illumination light source 21, and at least the barcode B (Region including one half of the LED), and is composed of, for example, a red LED and a lens provided on the emission side of the LED. The second illumination light source 22 corresponds to an example of “second illumination means”, and is illuminated by the second region (second illumination light source 22) shifted in the longitudinal direction from the first region of the barcode B. A region including at least the other half of the barcode B). The second illumination light source 22 is also composed of, for example, a red LED and a lens provided on the emission side of the LED. As shown in FIGS. 1 and 2, when the barcode B is set at a predetermined reading position, the first area (area irradiated by the first illumination light source 21) and the second area (second illumination). The region irradiated by the light source 22 partially overlaps.

  In the present embodiment, the first illumination light source 21 and the second illumination light source 22 can independently emit the illumination lights Lf1 and Lf2, respectively, and these illumination lights Lf1 and Lf2 are passed through the reading port provided in the case. The reading object R is irradiated. Note that a barcode B as an example of an identification code is affixed to the reading object R.

The light receiving optical system includes a first imaging lens 26, a second imaging lens 27, a light receiving sensor 28, and a reflecting mirror (not shown).
The light receiving sensor 28 shown in FIGS. 1 and 2 is formed by arranging light receiving elements, and is constituted by, for example, a CCD line sensor. The light receiving sensor 28 is configured to be able to receive the reflected lights Lr1 and Lr2 reflected by the barcode B, and the reflected light Lr1 is incident through the first imaging lens 26, and the reflected light. Lr2 is mounted on a printed wiring board (not shown) so that it can receive both incident light incident via the second imaging lens 27.

  The first imaging lens 26 and the second imaging lens 27 correspond to an example of “imaging means” that forms an image of the barcode B. The first imaging lens 26 corresponds to an example of “first imaging means”, and condenses the reflected light Lr1 reflected by the barcode B from the illumination light Lf1 from the first illumination light source 21. The image on the first region side of the bar code B is formed over the longitudinal majority region of the light receiving sensor 28 (for example, substantially the entire region of the light receiving sensor 28). The second imaging lens 27 corresponds to an example of “second imaging means”, and collects the reflected light Lr2 obtained by reflecting the illumination light Lf2 from the second illumination light source 22 by the barcode B. The second region side image that partially illuminates and overlaps the first region side image is formed over the longitudinal majority region of the light receiving sensor 28 (for example, substantially the entire region of the light receiving sensor 28). Yes.

  1 and FIG. 2, the illustration of the reflecting mirror is omitted, but the reflecting mirrors are respectively provided on the paths where the reflected lights Lr1 and Lr2 reach the first imaging lens 26 and the second imaging lens 27. A reflecting mirror may be arranged on a path from the first imaging lens 26 and the second imaging lens 27 to the light receiving sensor 28.

  Next, a configuration outline of the microcomputer system will be described. As shown in FIG. 1, the microcomputer system includes an amplification circuit 31, an A / D conversion circuit 33, a memory 35, an address generation circuit 36, a synchronization signal generation circuit 38, a control circuit 40, an operation switch 50, an LED 49, a buzzer 44, and a liquid crystal. It comprises a display 47, a communication interface 48 and the like.

  The image signal (analog signal) output from the light receiving sensor 28 of the optical system is amplified by a predetermined gain by being input to the amplifier circuit 31, and then input from the analog signal when input to the A / D conversion circuit 33. Converted into a digital signal. When a digitized image signal, that is, image data (image information) is input to a memory 35 formed of a RAM or the like (the memory 35 corresponds to an example of “storage means”), a predetermined image data storage area is stored. Accumulated in. The synchronization signal generation circuit 38 is configured to generate a synchronization signal for the light receiving sensor 28 and the address generation circuit 36, and the address generation circuit 36 is based on the synchronization signal supplied from the synchronization signal generation circuit 38. Thus, the storage address of the image data stored in the memory 35 can be generated. That is, in this configuration, since the storage address is generated in response to the synchronization signal, the image data output from the light receiving sensor 28 in response to the synchronization signal is stored in response to the synchronization signal. It is stored in the address area.

The control circuit 40 is a microcomputer capable of controlling the entire barcode reader 1 and includes a CPU, a system bus, an input / output interface, and the like. The control circuit 40 can constitute an information processing apparatus together with the memory 35 and has an information processing function. The control circuit 40 is configured to be connectable to various input / output devices (peripheral devices) via a built-in input / output interface. In the case of this embodiment, the operation switch 50, the LED 49, the buzzer 44, and the liquid crystal display. A device 47, a communication interface 48, and the like are connected. Thereby, for example, monitoring and management of the operation switch 50, on / off of the sound of the buzzer 44 capable of generating a beep sound and an alarm sound, communication control of the communication interface 48 with the code content of the read barcode B to an external device, etc. Is possible.
The control circuit 40 corresponds to an example of “illumination control means”, “exposure control means”, and “decoding means”, and examples of functioning as these means will be described later.

  The operation switch 50 is a switch configured to allow external operation (for example, pressing operation), and gives a signal corresponding to the external operation to the control circuit 40. In the barcode reader 1 according to the present embodiment, barcode reading is started with the operation of the operation switch 50 as a trigger.

Next, barcode reading processing will be described.
The reading process shown in FIG. 3 is started when the operation switch 50 of FIG. 1 is operated. First, in S10, the illumination means (that is, the first illumination light source 21 and the second illumination light source 22) is changed to the first. Processing to set one lighting state is performed. This first illumination state is a state in which the first region is illuminated brighter than the second region. In this embodiment, the first illumination light source 21 shown in FIGS. 1 and 2 is turned on, and the second illumination light source 22 is turned on. Realized by turning off. FIG. 4 illustrates the timing of the control. As shown in FIG. 4, an ON signal (first display) is sent from the control circuit 40 to the first drive circuit (not shown) that drives the first illumination light source 21. (Illumination light source drive signal) is given, and an off signal (second illumination light source non-drive signal) is given to a second drive circuit (not shown) for driving the second illumination light source 22, whereby the illumination means The lighting state is set. In this way, the control of the illumination means is performed by the control circuit 40 that functions as the “illumination control means”.

  Further, an exposure signal is output from the control circuit 40 to the light receiving sensor 28 at the same time as or after the first illumination light source 21 is turned on. This exposure signal is a signal for causing the light receiving sensor 28 to perform exposure, and the light receiving sensor 28 performs exposure while the exposure signal is output (S20). Thus, the exposure control of the light receiving sensor 28 is performed by the control circuit 40 functioning as “exposure control means”.

  Then, when a predetermined control time (exposure time) has elapsed after the start of exposure, the process proceeds to Yes in S30 to perform control for causing the light receiving sensor 28 to output image data (S40). Specifically, as shown in FIG. 4, the exposure signal is stopped and, after the stop, an image capture signal is given to the light receiving sensor 28. Specifically, an image capture signal is given from the control circuit 40 to the synchronization signal generation circuit 38, and the light receiving sensor 28 outputs the stored image data triggered by the synchronization signal output according to the capture signal. It will be. The image data output at this time corresponds to “first image data” formed by forming an image on the first region side in the first illumination state, and the output first image data is an amplification circuit. Amplified with a predetermined gain at 31, converted from an analog signal to a digital signal by an A / D conversion circuit 33, and stored in the memory 35.

  Further, a binarization process for binarizing the first image data is performed (S50). This binarization process is a process of generating a light / dark distribution of the first region by dividing the obtained first image data into a light level and a dark level based on a predetermined threshold. When a barcode as shown in FIG. 5A is to be read, a signal waveform as shown in FIG. 5B is obtained from the left image (image on the first region side), and the right image (second image). A signal waveform as shown in FIG. 5C is obtained by the image on the region side. In this signal waveform, if the comparison processing is performed so that the portion exceeding the threshold is set to the light level and the portion below the threshold is set to the dark level, the position and width of the light level region and the position and width of the dark level region are specified. Possible bright / dark pattern data (see FIGS. 6A and 6B) is obtained. The binarization processing of the first image data in S50 is performed in this way, and light / dark pattern data as shown in FIG. 6A is generated, and the obtained light / dark pattern data is stored in the memory 35 (S60). ).

  Thereafter, in S70, processing for setting the illumination means (that is, the first illumination light source 21 and the second illumination light source 22) to the second illumination state is performed. This second illumination state is a state in which the second region is illuminated brighter than the first region, and is realized by turning off the first illumination light source 21 and turning on the second illumination light source 22. Specifically, an off signal (first illumination light source non-drive signal) is given from a control circuit 40 functioning as “illumination control means” to a first drive circuit (not shown) that drives the first illumination light source 21. In addition, an ON signal (second illumination light source drive signal) is given to a second drive circuit (not shown) that drives the second illumination light source 22, thereby setting the illumination means to the second illumination state.

  An exposure signal is output from the control circuit 40 to the light receiving sensor 28 simultaneously with or after the second illumination light source 22 is turned on, and exposure is performed by the light receiving sensor 28 while the exposure signal is being output. (S80). When a predetermined control time (exposure time) has elapsed after the start of exposure, the process proceeds to Yes in S90, and control is performed to cause the light receiving sensor 28 to output image data (S100). This control is performed by the control circuit 40 in the same manner as in S40. The exposure signal is stopped and, after the stop, the capture signal is given to the synchronization signal generation circuit 38 (FIG. 1). The light receiving sensor 28 outputs the stored image data using a synchronization signal output according to the capture signal as a trigger. This image data corresponds to “second image data” formed by forming an image on the second region side in the second illumination state. The output second image data is predetermined by the amplification circuit 31. Amplified by the gain, converted from an analog signal to a digital signal by the A / D conversion circuit 33, and stored in the memory 35.

  Further, binarization processing for binarizing the second image data is performed (S110). The binarization process is the same as in S50, and the obtained second image data is divided into a light level and a dark level based on a predetermined threshold value, a light / dark distribution is generated, and light / dark pattern data is stored in the memory 35. Store (S120). In this way, the first image data and the second image data are respectively stored in the memory 35 as light / dark pattern data.

  Thereafter, a synthesis process is performed (S130). In this synthesis process, first, the light / dark pattern data related to the first image data and the light / dark pattern data related to the second image data are read from the memory 35. 6A conceptually illustrates the light / dark pattern data of the first image data, and FIG. 6B conceptually illustrates the light / dark pattern data of the second image data. In the synthesizing process, coincident portions of these patterns are detected, and both patterns are connected based on the coincident portions as shown in FIG. 6C to generate one pattern data. In this manner, the first image data and the second image data are synthesized based on the overlapping portion between the first image data and the second image data stored in the memory 35.

  After the synthesizing process of S130, a confirmation process is performed as to whether or not the obtained data can be recognized as a code (S140). Specifically, it is determined whether or not one pattern data synthesized by the synthesizing process of S130 can be recognized as a code corresponding to the entire area of the barcode B. If data that can be recognized as a code cannot be obtained, for example, it cannot be detected, the process proceeds to No in S140. On the other hand, if appropriate synthesis processing is performed and one pattern data synthesized as shown in FIG. 6C can be recognized as a code corresponding to the entire area of the barcode B, the process proceeds to Yes in S140, and synthesis is performed. The composite decoded data obtained by decoding the single pattern data is stored in the memory 35 (S150), the illumination light of the illumination unit is turned off (S170), and the process is terminated. The control circuit 40 thus functions as “decoding means”.

  In addition, when progressing to No in S140, the process (S150) which changes control conditions is performed, and the process after S10 is performed again. There are various examples of changing the control condition in S150, but there are processes such as changing the amount of illumination light emitted from the illumination means and changing the threshold values shown in FIGS. 5B and 5C. Can be mentioned.

  According to the configuration of the present embodiment, the first imaging lens 26 that forms an image on the first region side of the barcode B over the majority region of the light receiving sensor 28, the image on the first region side, and a part thereof A second imaging lens 27 that forms an image of the overlapping second region side over the majority region of the light receiving sensor 28, and when the illumination means is set to the first illumination state, the first region side The first image data formed by forming the first image is output to the light receiving sensor 28, and when the second illumination state is set, the second image data formed by forming the second region side image is received by the light receiving sensor. 28 is made to output. Therefore, it is possible to quickly acquire images of two areas in the barcode B without complicated operations. In addition, since the composite decoded data is generated by synthesizing and decoding the first image data and the second image data based on the overlapping part of the first image data and the second image data, a long barcode is high. It can be read well with resolution. In addition, according to this configuration, a long barcode can be read well without increasing the size of the light receiving sensor 28, so that the configuration is excellent in terms of cost.

  Moreover, the 1st illumination light source 21 irradiates the area | region of the longitudinal direction one side in barcode B, and the 2nd illumination light source 22 irradiates the area | region on the opposite side to the one side (irradiation side by the 1st illumination light source 21). When the first illumination state is set, the first image data formed by forming an image on one side of the barcode B is output to the light receiving sensor 28 and set to the second illumination state. The second image data formed by forming the opposite image is output to the light receiving sensor 28. According to this configuration, it is possible to divide the barcode B, which tends to be long, into two regions and read it well with high resolution, and to simplify and speed up the reading operation.

  In the first illumination state, the illumination of the first illumination light source 21 is turned on and the illumination of the second illumination light source 22 is turned off. In the second illumination state, the illumination of the first illumination light source 21 is turned off and the second illumination is turned on. The first illumination light source 21 and the second illumination light source 22 are controlled to turn on the illumination of the light source 22. Therefore, when the image on the first area side is read, the influence of the second illumination light source 22 can be eliminated, and the image on the first area side can be read with high accuracy and good. Similarly, when reading the image on the second region side, the influence of the first illumination light source 21 can be eliminated, so that the image on the second region side can be read with high accuracy and good. Furthermore, since the illumination means for illuminating the side that is not the reading side (for example, the second illumination light source 22 that illuminates the side that is not the reading side when reading the first region side) is turned off, power saving is also achieved. It becomes a structure.

[Reference example]
Next, a reference example will be described.
FIG. 7 is a block diagram schematically showing an electrical configuration of the barcode reader 100 according to the reference example . FIG. 8 is an explanatory diagram for explaining illumination means and image forming means in the barcode reader 100 of FIG. FIG. 9 is a flowchart illustrating the flow of reading process control in the barcode reader 100.

The circuit unit 120 of the barcode reader 100 according to the reference example is partially different from the circuit unit 20 of the first embodiment, but the amplifier circuit 31, the A / D conversion circuit 33, the synchronization signal generation circuit 38, and the address generation circuit 36. The operation switch 50, the LED 49, the buzzer 44, the liquid crystal display 47, the communication interface 48, and the like have the same configuration as in the first embodiment. Therefore, the same reference numerals as those in the first embodiment are assigned to these, and detailed description thereof is omitted.

  The barcode reader 100 has an illumination unit that irradiates illumination light Lf1 and Lf2 to a longitudinal barcode B (identification code), an imaging unit that forms an image of the barcode B, and a light receiving element. It includes a light receiving sensor 128 and a memory 135 (memory 135 corresponds to an example of a storage unit) that stores image data of an identification code output from the light receiving sensor 128. The light receiving sensor 128 has the same configuration as the light receiving sensor 28 (FIG. 1) of the first embodiment, and the memory 135 has the same configuration as the memory 35 of the first embodiment. .

  The illumination means of the barcode reader 100 irradiates the first region in the longitudinal direction of the barcode B (the region illuminated by the first illumination light source 121 and the region including at least one half of the barcode B). The illumination light source 121 and a second region (a region irradiated by the second illumination light source 122 and including at least the other half of the barcode B) shifted in the longitudinal direction from the first region of the identification code are irradiated. And two illumination light sources 122. The first illumination light source 121 has the same configuration as the first illumination light source 21 (FIG. 1) of the first embodiment, and the second illumination light source 122 is also the second illumination light source 22 (FIG. 1) of the first embodiment. ) Is used.

  The image forming unit of the barcode reader 100 includes a prism 126 that functions as a light direction changing unit, an image forming lens 127 that takes in light from the prism 126, and an actuator (not shown) that controls the displacement of the prism 126. A first imaging state in which an image on the first region (region irradiated by the first illumination light source 121) side of the barcode B is formed over a majority region of the light receiving sensor 128, and the first region side It is possible to switch to the second imaging state in which an image on the second region (region irradiated by the second illumination light source 122) side partially overlapping with the first image is formed over the majority region of the light receiving sensor 128. ing.

The actuator is composed of, for example, a stepping motor, and the prism 126 is in a first rotation state in which the reflected light Lr1 from the first region side is captured by the actuator and the control circuit 140 (the state of the two-dot chain line in FIGS. 7 and 8). ) And the second rotation state (the state indicated by the solid line in FIGS. 7 and 8) in which the reflected light Lr2 from the second region side is taken in. That is, when the control circuit 140 outputs a signal indicating the first rotation state, the actuator is driven, and the prism 126 is in the state of the two-dot chain line shown in FIGS. By outputting the signal to be in a state, the prism 126 becomes a solid line state shown in FIGS. When the prism 126 is in a two-dot chain line state, the reflected light Lr1 from the first region side enters the prism 126 and is deflected toward the imaging lens 127 by the prism 126 and passes through the imaging lens 127. Light is received over the majority region in the longitudinal direction of the light receiving sensor 128 .

A control circuit 140 shown in FIG. 7 is a microcomputer capable of controlling the entire barcode reader 100, and includes a CPU, a system bus, an input / output interface, and the like, and can constitute an information processing apparatus together with the memory 135. to have a function.

Next, barcode reading processing will be described. The reading process shown in FIG. 9 is started when the operation switch 50 of FIG. 7 is operated. First, in S200, the illumination means (that is, the first illumination light source 121 and the second illumination light source 122) is changed to the first. Processing to set one lighting state is performed. This first illumination state is a state in which the first region is illuminated brighter than the second region. In the reference example , the first illumination light source 121 shown in FIGS. 7 and 8 is turned on and the second illumination light source 122 is turned off. It is realized by doing .

Further, processing for setting the imaging means to the first imaging state is performed (S210). The first imaging state is as described above, and a signal for setting the prism 126 to the first rotation state is output from the control circuit 140 to an actuator (not shown) that drives the prism 126, thereby driving the actuator. Thus, the prism 126 enters the first rotation state (a state in which the reflected light Lr1 from the first region side can be taken in and deflected toward the imaging lens 127) .

Further, an exposure signal is output from the control circuit 140 to the light receiving sensor 128. This exposure signal is a signal for causing the light receiving sensor 128 to perform exposure, and the light receiving sensor 128 performs exposure while the exposure signal is output (S220 ).

  Then, when a predetermined control time (exposure time) has elapsed after the start of exposure, the process proceeds to Yes in S230, and control is performed to output image data (first image data) to the light receiving sensor 128 (S140). Note that the processing of S240, S250, and S260 is the same as the processing of S40, S50, and S60 (FIG. 3) of the first embodiment, and when the processing of S260 ends, the light and dark pattern data of the first image data is stored in the memory 135. Will be stored.

Thereafter, in S270, processing for setting the illumination means (that is, the first illumination light source 121 and the second illumination light source 122) to the second illumination state is performed. This second illumination state is a state in which the second region is illuminated brighter than the first region, and is realized by turning off the first illumination light source 121 and turning on the second illumination light source 122 .

  Further, processing for setting the imaging means to the second imaging state is performed (S280). The second imaging state is as described above, and a signal for setting the prism 126 to the second rotation state is output from the control circuit 140 to an actuator (not shown) that drives the prism 126, thereby driving the actuator. As a result, the prism 126 enters a second rotation state (a state in which the reflected light Lr2 from the second region side can be taken in and deflected toward the imaging lens 127). In this way, when the second illumination state is set, the control circuit 140 functioning as the image formation control means is switched to the second image formation state.

  Then, an exposure signal is output from the control circuit 140 to the light receiving sensor 128, and exposure is performed by the light receiving sensor 128 while the exposure signal is being output (S290). Then, when a predetermined control time (exposure time) has elapsed after the start of exposure, the process proceeds to Yes in S300 to perform control for causing the light receiving sensor 128 to output image data (S310). Note that the processing of S310, S320, and S330 is the same as the processing of S100, S110, and S120 (FIG. 3) of the first embodiment, and when the processing of S330 ends, the light and dark pattern data of the second image data is stored in the memory 135. Will be stored. In this way, the first image data and the second image data are respectively stored in the memory 135 as light / dark pattern data.

  The processes of S340, S350, S370, and S380 are the same as the processes of S130, S140, S150, and S160 of the first embodiment, and the first image data stored in the memory 135 and the second image data are overlapped. Based on this, the first image data and the second image data are synthesized and output. In addition, when progressing to No in S350, the process (S360) which changes control conditions is performed, and the process after S200 is performed again. This setting condition changing process can also be performed in the same manner as the process of S150 in the first embodiment (FIG. 3).

According to the configuration of the reference example , the images of the two regions in the barcode B (the image on the first region side and the image on the second region side) can be quickly acquired without complicated operations. Further, since the composite decoded data is generated by synthesizing and decoding the first image data and the second image data based on the overlapping part of the first image data and the second image data, a long barcode is high. It can be read well with resolution. In addition, according to this configuration, a long barcode can be satisfactorily read without increasing the size of the light receiving sensor 128, so that the configuration is excellent in terms of cost.

[Other Embodiments]
The present invention is not limited to the embodiments described with reference to the above description and drawings. For example, the following embodiments are also included in the technical scope of the present invention.

  In the above-described embodiment, an example in which images of two regions are combined has been described, but three or more may be used. For example, a third illumination unit may be provided, and different areas shifted in the longitudinal direction may be irradiated by the first illumination unit, the second illumination unit, and the third illumination unit, respectively. In this case, if combined decode data is generated by combining and decoding the first image data on the first region side, the second image data on the second region side, and the third image data on the third region side based on the overlapping portion. Good.

  In the embodiment, in the first illumination state, the illumination of the first illumination light source is turned on and the illumination of the second illumination light source is turned off. In the second illumination state, the illumination of the first illumination light source is turned off and the second illumination is turned on. Although the 1st illumination light source and the 2nd illumination light source were controlled so that illumination of a light source may be turned on, it is not limited to this. For example, in the first illumination state, the illumination of the first illumination light source is set to a predetermined first light amount, and the illumination of the second illumination light source is turned on with a light amount lower than the first light amount. The illumination of the second illumination light source may be set to a predetermined second light amount, and the illumination of the first illumination light source may be turned on with a light amount that is less than the second light amount.

In the first embodiment, the example as shown in FIG. 2 is given as the imaging unit, but the configuration capable of imaging the image on the first region side and the image on the second region side over the majority region of the light receiving sensor 28. If it is, it will not be limited to this. For example, the configuration shown in FIGS. 10 and 11 may be used.
In FIG. 10, the first illumination light source 21, the second illumination light source 22, and the light receiving sensor 28 similar to those in the first embodiment are provided, and the imaging lens 326 that receives the reflected light Lr <b> 1 from the first region side and the light reception. An optical fiber 328 that guides light transmitted through the imaging lens 326 is provided between the sensor 28 and reflected light from the first region side is guided to the light receiving sensor 28 by the optical fiber 328. Yes. The reflected light Lr2 from the second region side is incident on the imaging lens 327. However, the light transmitted through the imaging lens 327 may be received by the light receiving sensor 28 as it is, and may be received by an optical fiber. A form guided by the light receiving sensor 28 may be employed.
Also in FIG. 11, the same first illumination light source 21, second illumination light source 22, and light receiving sensor 28 as those in the first embodiment are provided. In this example, a mirror 425 and a semi-transmissive mirror 424 are provided, so that the reflected light Lr1 from the first region side is reflected by the mirror 425, reflected by the semi-transmissive mirror 424, and guided to the prism 426. It has become. The semi-transmissive mirror 424 is configured to transmit the reflected light Lr2 from the second region side. The reflected light Lr2 is transmitted through the semi-transmissive mirror 424 and guided to the prism 426. Any reflected light Lr 1, Lr 2 is deflected toward the imaging lens 427 by the prism 426, and is received over the majority region of the light receiving sensor 28.

FIG. 1 is a block diagram schematically showing an electrical configuration of a barcode reader 1 according to the first embodiment of the present invention. FIG. 2 is an explanatory diagram for explaining illumination means and image forming means in the barcode reader 1 of FIG. FIG. 3 is a flowchart illustrating a control flow of reading processing in the barcode reader 1 of FIG. FIG. 4 is a timing chart for explaining illumination timing, exposure timing, and image capture timing. FIG. 5 is an explanatory diagram illustrating an image on the first area side, an image on the second area side, and the like. FIG. 6 is an explanatory diagram for explaining the generation of the composite decoded data. FIG. 7 is a block diagram schematically showing an electrical configuration of the barcode reader 100 according to the reference example . FIG. 8 is an explanatory diagram for explaining illumination means and image forming means in the barcode reader 100 of FIG. FIG. 9 is a flowchart illustrating a flow of control of reading processing in the barcode reader 100 of FIG. FIG. 10 is an explanatory view showing another example 1 of the imaging means different from FIG. FIG. 11 is an explanatory view showing another example 2 of the imaging means different from FIG.

Explanation of symbols

1,100 ... Bar code reader (optical information reader)
21, 121... First illumination light source (first illumination means)
22, 122 ... second illumination light source (second illumination means)
26. First imaging lens (imaging means, first imaging means)
27. Second imaging lens (imaging means, second imaging means)
28, 128 ... Light receiving sensor 35, 135 ... Memory (storage means)
40. Control circuit (illumination control means, exposure control means, decoding means)
126 ... Prism (imaging means)
127 ... Lens (imaging means)
140... Control circuit (illumination control means, exposure control means, image formation control means, decoding means)
B ... Bar code (identification code)

Claims (3)

A light receiving sensor comprising a line sensor in which light receiving elements are arranged;
Illuminating means for irradiating illumination light to an identification code comprising a longitudinal barcode ;
Illumination control means for controlling the illumination means;
Exposure control means for controlling exposure of the light receiving sensor;
Imaging means for forming an image of the identification code;
Storage means for storing image data of the identification code output from the light receiving sensor;
Decoding means for decoding the identification code based on the image data stored in the storage means;
An optical information reader comprising:
The illumination means includes
First illumination means for illuminating a first region in the longitudinal direction of the identification code;
A second illuminating means for irradiating a second region shifted in the longitudinal direction from the first region of the identification code;
With
The imaging means is
First imaging means for forming an image on the first region side of the identification code over a majority region of the light receiving sensor;
A second image forming means for forming an image on the second region side partially overlapping with the image on the first region side over a majority region of the light receiving sensor;
With
The illumination control means includes
The illumination unit can be set and changed between a first illumination state in which the first region is illuminated brighter than the second region and a second illumination state in which the second region is illuminated brighter than the first region. Configured,
The exposure control means includes
When the illumination unit is set to the first illumination state, the first image data formed by forming an image on the first region side is output to the light receiving sensor, and the second illumination state is set. Sometimes, the second image data formed by forming an image of the second region side is configured to output the light receiving sensor,
The storage means
Storing the first image data and the second image data output by the light receiving sensor,
The decoding means includes
Based on an overlap portion between the first image data and the second image data stored in the storage means, combined decode data is generated by combining and decoding the first image data and the second image data. An optical information reader.   The first illumination unit irradiates a region on one side in the longitudinal direction of the barcode, and the second illumination unit has a configuration of irradiating a region opposite to the one side,
  The exposure control unit causes the light receiving sensor to output the first image data formed by forming the image on the one side of the barcode when the illumination unit is set to the first illumination state. 2. The configuration according to claim 1, wherein when the second illumination state is set, the light receiving sensor outputs the second image data formed by forming the image on the opposite side. Optical information reader.   The illumination control means turns on the illumination of the first illumination means and turns off the illumination of the second illumination means in the first illumination state, and turns on the illumination of the first illumination means in the second illumination state. 3. The optical information reader according to claim 1, wherein the first illumination unit and the second illumination unit are controlled to turn off and turn on the illumination of the second illumination unit. 4.

Images