JPH0741648U - Code reader - Google Patents

Abstract

(57) [Abstract] [Purpose] It is an object of the present invention to provide a reader which is not affected by external light and which can be easily adjusted. [Structure] The irradiation light 10L emitted from the projector 10 is
The light is projected onto the projection polygon mirror 20T, and the barcode 45 is scanned by rotation in the direction of the arrow 300. The reflected light 10R from the bar code 45 reaches the light-receiving polygon mirror 20J which is formed larger than the light-projecting polygon mirror 20T and is displaced by a predetermined angle.
The light is received by the light receiver 30 by the rotation in the direction of the arrow 300. Therefore, the reflected light 10R is surely incident on the light receiver 30, the barcode 45 is accurately read, and accurate reading can be performed even when used in a place where the external light is strong. In addition, each unit can be adjusted individually on the light-projecting side and the light-receiving side, which facilitates the adjustment.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a reading device, and more particularly to reading accuracy and facilitating adjustment.

[0002]

[Prior art]

 Generally, there are various types of readers. In recent years, barcodes have been added to many products for the purpose of product management, etc., so barcode reading devices are used in factories and distribution processes.

A bar code reading device is a device that illuminates an original bar code attached to a product and discriminates the type of the product based on the reflected light. Generally, there are two types of operation methods of the bar code reader, which are called different axis method and coaxial method. The different axis type and coaxial type bar code readers will be described below.

FIG. 5A is a perspective view showing a bar code reader 100 of a different axis type. The barcode reader 100 is composed of a semiconductor laser 10, a collimator lens 15, a polygon mirror 20, a condenser lens 25, and a light receiving section 30. Here, the polygon mirror 20 refers to a mirror having six reflecting surfaces. A barcode 45 is arranged at a predetermined position near the barcode reading device 100.

Next, an outline of the operation of the different axis type bar code reading apparatus 100 will be described with reference to FIG. 5A. The irradiation light 10L emitted from the semiconductor laser 10 is converged in a parallel direction by the collimator lens 15 and then irradiated on the reflecting surface of the polygon mirror 20. The polygon mirror 20 rotates about the central axis 20C in the direction of arrow 300. As a result, the angle of each reflecting surface of the polygon mirror 20 with respect to the semiconductor laser 10 changes sequentially.

Irradiation light 10L irradiated on the reflecting surface of the polygon mirror 20 is scanned on the barcode 45 in the direction of arrow 350 by the rotation of the polygon mirror 20 in the direction of arrow 300. Since the polygon mirror 20 rotates at a high speed, the scanning speed of the irradiation light 10L is also high.

The irradiation light scanned at a high speed on the bar code 45 is reflected including the light and shade of the code (such as the interval between black and white portions). A part of the reflected light (reflected light 10R) is collected by the condenser lens 25 and given to the light receiving unit 30. The light receiving unit 30 receives the reflected light 10R from the condenser lens 25 and identifies the product with the bar code 45 based on the shading included in the reflected light 10R. In this way, reliable barcode reading can be performed.

Next, the coaxial bar code reader will be described. FIG. 5B is a perspective view showing a coaxial type bar code reader 200. The bar code reading device 200 includes a semiconductor laser 10, a collimator lens 15, a mirror 17, a polygon mirror 20, a condenser lens 25, and a light receiving unit 30. Here, the bar code reading device 200 is provided with the mirror 17, and the semiconductor laser 10, the collimator lens 15 and the mirror 17 are provided in the vertical direction, which is different from the bar code reading device 100 of the different axis type. Is different. Further, unlike the case of the different axis method, the reflection surface of the polygon mirror 20 and the condenser lens are formed large, which is also different from the different axis method.

The operation of the coaxial bar code reader 200 will be described with reference to FIG. 5B. The irradiation light 10L emitted from the semiconductor laser 10 in the vertical direction is converged by the collimator lens 15, converted into substantially parallel light by the mirror 17, and irradiated on the reflecting surface of the polygon mirror 20.

Here again, the polygon mirror 20 rotates at a high speed in the direction of the arrow 300, whereby the angle of each reflecting surface of the polygon mirror 20 with respect to the mirror 17 changes sequentially.

The irradiation light 10L applied to the reflecting surface of the polygon mirror 20 is swept over the barcode 45 in the direction of arrow 350 at high speed by the rotation of the polygon mirror 20 in the direction of arrow 300.

The irradiation light 10L scanned on the bar code 45 is reflected by including the light and shade of the code (such as the interval between black and white portions). The reflected light (reflected light 10R) reaches the polygon mirror 20 while being diffused, and is given to the condenser lens 25 by being rotated in the direction of the arrow 300. The reflected light 10R collected by the condenser lens 25 is narrowed down and given to the light receiving unit 30.

The light receiving unit 30 receives the reflected light 10R from the condenser lens 25, and identifies the product with the bar code 45 based on the shading included in the reflected light 10R. In this way, the bar code can be reliably read.

[0014]

[Problems to be solved by the device]

 However, the conventional bar code reader has the following problems.

A plan view of the different axis type barcode reading apparatus 100 shown in FIG. 5A is shown in FIG. 4A. Normally, the light scanned on the bar code 45 is diffused into the width W400 as the reflected light 10R.

In the different-axis bar code reader 100, the condenser lens 25 uniformly collects the entire reflected light 10R diffused at intervals of width 400. For this reason, in the different axis type bar code reader 100, noise included in the diffused reflected light 10R is also condensed. Therefore, it becomes difficult for the light receiving unit 30 to identify the shade of the barcode 45 to be read (such as the interval between black and white portions) due to the noise included in the reflected light 10R.

In addition, when the different-axis bar code reading device 100 is used in a place where the external light is strong, there is a problem that it becomes more difficult to distinguish the shade of the bar code 45 due to the influence of the external light. In such a case, the different-axis barcode reader 100 recognizes that the barcode is different from the barcode actually used for reading, and there is a problem in that accurate reading cannot be performed. there were.

Next, a plan view of the coaxial barcode reader 200 shown in FIG. 5B is shown in FIG. 4B. In this method, the irradiation light 10L is applied to the bar code 45 by the rotation of the polygon mirror 20, and the reflected light 10R from the bar code 45 is given to the condenser lens 25 by the polygon mirror formed in a large size. Therefore, it is easy to read the light and shade of the barcode 45 even when the barcode 45 is used in a place where the external light is strong unlike the different axis method.

However, a mirror 17 is provided on the optical path of the reflected light 10R given to the condenser lens 25 (FIG. 4B). Therefore, the reflected light 10R is blocked by the mirror 17 before being condensed by the condenser lens 25. That is, the shadow of the mirror 17 is formed on the condenser lens 25 over the width W200, and the reflected light 10R is not collected in the shadow portion. In particular, since the portion blocked by the mirror 17 is the portion with the strongest signal in the reflected light 10R, there is a problem that accurate reading cannot be performed by blocking this portion.

Further, as described above, in the coaxial barcode reader 200, the semiconductor laser 10, the collimator lens 15, and the mirror 17 are provided in the vertical direction. Therefore, in order to accurately read the barcode 45 included in the reflected light by causing the irradiation light 10L to be reflected by the polygon mirror 20 and scanning the barcode 45, the semiconductor laser 10, the collimator lens 15, and the mirror 17 must be read. There was a problem that it took time and effort to adjust each accurately. In particular, the mirror 17 is formed small in order to minimize the shadow caused by the mirror 17. For this reason, there is also a problem that it takes a lot of time to adjust each of the above parts accurately. Therefore, an object of the present invention is to provide a reader that is not affected by external light and is easy to adjust.

[0021]

[Means for Solving the Problems]

 The reading device according to claim 1, further comprising: an irradiation unit that emits irradiation light; and an irradiation light reflection unit that has a plurality of reflecting surfaces and that irradiates the reading object while scanning the irradiation light by rotating about a rotation axis. It has a plurality of reflecting surfaces that are displaced from the reflecting surface of the irradiation light reflecting means by a predetermined angle in the rotation direction, and by rotating about the rotation axis, the reading reflected light from the reading object is directed to the light receiving means. The reading reflected light reflecting means for reflecting the light and the light receiving means provided at a position different from the irradiation means on a plane perpendicular to the rotation axis are provided.

According to a second aspect of the present invention, the reading device has an irradiation unit that emits irradiation light and a plurality of reflecting surfaces that are not parallel to the rotation axis, and the irradiation object is irradiated with the irradiation light by rotating about the rotation axis. An irradiation light reflecting means for irradiating while scanning the light, and a plurality of reflecting surfaces substantially parallel to the rotation axis, and by rotating around the rotation axis, the reading reflection light from the reading object is received. And a light receiving unit provided at a position different from that of the irradiation unit on a plane including the rotation axis.

[0023]

[Action]

 The reading device according to claim 1 is provided with an irradiation light reflecting means separately from the reading reflected light reflecting means, and the reflecting surface of the irradiation light reflecting means and the reflecting surface of the reading reflected light reflecting means are displaced by a predetermined angle in the rotation direction. There is. Therefore, it is possible to make the irradiation light and the position of the light receiving means different from each other without providing a reflecting mirror in the optical path of the reading reflected light while making the optical paths of the irradiation light from the reflecting surface to the reading object and the reading reflected light almost the same. .

According to a second aspect of the present invention, the reading light reflection means is provided separately from the reading reflection light reflection means, and one of the reflection surface of the irradiation light reflection means and the reflection surface of the reading reflection light reflection means is used as a rotation axis. They are provided substantially parallel to each other and the other is provided so as not to be parallel. Therefore, the positions of the irradiation unit and the light receiving unit can be different without providing a reflecting mirror in the optical path of the reading reflected light while making the optical paths of the irradiation light from the reflecting surface to the reading target and the reading reflected light almost the same. .

[0025]

【Example】

 An embodiment of the reading device according to the present invention will be described below. FIG. 1A shows a bar code reader 400 of this embodiment. The bar code reading device 400 includes a light projector 10 as an irradiation unit, a polygon mirror 20, and a light receiver 30 as a light receiving unit.

In this embodiment, the semiconductor laser and the collimator lens are integrally formed in the light projector 10, and the polygon mirror 20 includes a projection polygon mirror 20T as an irradiation light reflection means and a reading reflection light reflection means. The light receiving polygon mirror 20J is integrally formed. Further, in the light receiver 30, a condenser lens and a light receiving section are integrally formed.

Here, a plurality of reflecting surfaces are formed on the polygon mirror 20, and the reflecting surface of the light projecting polygon mirror 20T is as small as possible (for example, about the same as a laser spot for irradiation light, for example, about 3 mm). The reflecting surface of the light-receiving polygon mirror 20J is formed as large as possible. Both reflecting surfaces are provided so as to be offset by a predetermined angle (about 25 degrees in this embodiment). A plan view of such a bar code reader 400 is shown in FIG.

The operation of the barcode reading apparatus 400 will be described with reference to FIGS. 1A and 2. First, the irradiation light 10L emitted from the light projector 10 strikes the reflecting surface of the projection polygon mirror 20T (FIGS. 1A and 2). The polygon mirror 20 rotates about the central axis 20C in the direction of arrow 300. Here, the light projecting polygon mirror 20T and the light receiving polygon mirror 20J rotate in the direction of the arrow 300 while maintaining the difference in angle (see FIG. 2). Therefore, the irradiation light 10L that hits the reflecting surface of the projection polygon mirror 20T is scanned at high speed on the barcode 45 in the direction of arrow 350 by the rotation of the polygon mirror 20.

On the other hand, the reflected light 10R from the barcode 45 strikes the reflecting surface of the light-receiving polygon mirror 20J while being diffused. As described above, the reflecting surface of the light-receiving polygon mirror 20J is formed to be larger than the reflecting surface of the light-projecting polygon mirror 20T, and it rotates while maintaining the above-mentioned angle difference from the light-projecting polygon mirror 20T. ing.

As a result, the reflected light 10R is reflected in the direction of the light receiver 30 only by the reflecting surface of the light-receiving polygon mirror 20J, and is not reflected in the direction of the light projector 10. That is, the reading position of the bar code 45 is sequentially changed by the rotation of the light-receiving polygon mirror 20J. Therefore, the reflected light 10R is surely incident on the light receiver 30, and the shade of the bar code 45 can be accurately read. This makes it possible to read barcodes accurately even when used in places with strong external light.

In addition, also in the barcode reading apparatus 400, in order to perform accurate reading, each part is adjusted. On the projecting side (projector 10 and projecting polygon mirror 20T), adjustment is necessary to accurately reflect the irradiation light 10L to the reflecting surface of the projecting polygon mirror 20T and to scan the barcode. Becomes On the other hand, on the light receiving side (the light receiving polygon mirror 20J and the light receiver 30), it is necessary to make an adjustment so that the reflected light 10R is reflected by the reflection surface of the light receiving polygon mirror 20J and is incident on the light receiver 30. For example, the angle of the reflecting surface of the light projecting polygon mirror 20T with respect to the light projecting device 10 and the angle of the light receiving device 30 with respect to the reflecting surface of the light receiving polygon mirror 20J correspond to this.

Further, the adjustment in the bar code reading device 400 can be individually performed on the light projecting side (light projecting device 10 and the light projecting polygon mirror 20T) and the light receiving side (light receiving polygon mirror 20J and the light receiving device 30). .

That is, by using the bar code reading device 400, it is possible to read the bar code more accurately without being affected by the external light, because the bar code is easily adjusted. Next, FIG. 1B is a perspective view showing another embodiment of the bar code reading apparatus according to the present invention. The bar code reading device 500 according to this embodiment also includes a light projector 10, a polygon mirror 20, and a light receiver 30. The projector 10 has a semiconductor laser and a collimator lens integrally formed therein, and the light receiver 30 has a condenser lens and a light receiving unit integrally formed therein.

However, the polygon mirror 20 of the present embodiment has a triple structure in which the light projecting polygon mirror 20T is sandwiched between the first light receiving polygon mirror 20J1 and the second light receiving polygon mirror 20J2. ing.

Also in this case, the light projecting polygon mirror 20T is formed as small as possible, and the first light receiving polygon mirror 20J1 and the first light receiving polygon mirror 20J2 are formed as large as possible. Further, the light projecting polygon mirror 20T, the first light receiving polygon mirror 20J1 and the second light receiving polygon mirror 20J2 are provided so as to be offset by a predetermined angle.

The operation of the barcode reading apparatus 500 of this embodiment is the same as the operation of the barcode reading apparatus 400 described above.

Also in this embodiment, the two light receiving polygons 20J1 and 20J2 are used to supply the reflected light 10R to the light receiver 30. Therefore, the reflected light 10R can be applied to the light receiver 30 more accurately. That is, the barcode can be read more accurately even when used in a place where the external light is strong.

Further, the adjustment of each part in this embodiment is performed by the light projecting side (light projector 10 and light projecting polygon mirror 20T) and the light receiving side (first light receiving polygon mirror 20J1, second light receiving polygon mirror 20J2, and light receiving device). 30) can be done individually.

That is, when the bar code reading device 500 is used, the bar code is not affected by external light, the adjustment is easy, and the bar code can be read more accurately. Next, another embodiment of the bar code reader according to the present invention will be described. FIG. 3A is a side view showing the configuration of the barcode reading device 600 according to this embodiment. For convenience of explanation, the bar code is not shown here. Also in this embodiment, the bar code reading device 600 is composed of the light projector 10, the polygon mirror 20, and the light receiver 30. Further, the projector 10 has a semiconductor laser and a collimator lens integrally formed therein, and the light receiver 30 has a condenser lens and a light receiving unit integrally formed therein. Further, the polygon mirror 20 is integrally formed with a light projecting polygon mirror 20T and a light receiving polygon mirror 20J, each having a plurality of reflecting surfaces.

However, while the light-receiving polygon mirror 20J has a plurality of reflecting surfaces that are substantially horizontal to the rotation axis 20C, the light-projecting polygon mirror 20T has a plurality of reflection surfaces that are not parallel to the rotation axis. The reflecting surface has an angle of β (for example, about 10 degrees in this embodiment).

Further, in this embodiment, unlike the above-mentioned embodiment, the light receiver 30 is provided above the light projector 10. Also in this embodiment, as shown in FIG. 3B, the polygon mirror 20 rotates about the central axis 20C in the direction of arrow 300.

The operation of such a barcode reading device 600 will be described. Irradiation light 10L emitted from the projector 10 hits the reflecting surface 20TR of the projecting polygon mirror 20T and is reflected at the angle β direction provided on the reflecting surface (FIG. 3A). The reflected irradiation light 10L is scanned at high speed on the barcode 45 in the direction of arrow 350 by the rotation of the polygon mirror 20 (FIG. 3B).

Here, the reflected light 10R from the barcode 45 strikes the reflecting surface of the light-receiving polygon mirror 20J while being diffused. The light-receiving polygon mirror 20J gives the received reflected light 10R to the light receiver 30 by rotation (FIGS. 3A and 3B). As described above, the light receiver 30 is located above the light projector 10. Therefore, the light projector 10 and the light receiver 30 are provided on the same optical path, but the reflected light 10R enters the light receiver 30 without being blocked by the light projector 10.

As a result, the portion of the reflected light 10R having the strongest signal can be received by the light receiver 30. Therefore, the bar code can be read accurately even when used in a place where the external light is strong.

Further, also in the bar code reading apparatus 600 according to the present embodiment, adjustment of each part is performed on the light projecting side (light projecting device 10 and light projecting polygon mirror 20T) and light receiving side (light receiving polygon mirror 20J and light receiving device 30). ), Each can be done individually.

That is, by using the bar code reading device 600, it is possible to read the bar code without being affected by external light, easy to adjust, and accurate.

[0047]

[Effect of device]

 In the reading device according to the first aspect, the irradiation light reflecting means is provided separately from the reading reflected light reflecting means, and the reflecting surface of the irradiation light reflecting means and the reflecting surface of the reading reflected light reflecting means are displaced by a predetermined angle in the rotational direction. . Further, in claim 2, one of the reflection surface of the irradiation light reflection means and the reflection surface of the read reflection light reflection means is provided substantially parallel to the rotation axis, and the other is provided not parallel. That is, it is possible to make the positions of the irradiation unit and the light receiving unit different without providing a reflecting mirror in the optical path of the reading reflected light while making the optical paths of the irradiation light from the reflecting surface to the reading target and the reading reflected light almost the same. . Therefore, it is possible to provide a reading device that is not affected by external light and is easy to adjust.

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of a bar code reader according to the present invention.

FIG. 2 is a plan view showing a relationship between an apparatus for reading with the barcode reading apparatus shown in FIG. 1 and irradiation light and reflected light.

FIG. 3 is a side view showing the configuration of another embodiment of the bar code reading device according to the present invention and a plan view showing the relationship between the reading device and the irradiation light and the reflected light.

FIG. 4 is a plan view showing a relationship between a device and irradiation light and reflected light when reading is performed using a conventional barcode reading device.

FIG. 5 is a perspective view showing a configuration of a conventional barcode reading device, and irradiation light and reflected light.

[Explanation of symbols]

 10: Emitter 20: Polygon mirror 30: Light receiver 45: Bar code 10L: Irradiated light 10R: Reflected light 20J ... ... Polygon mirror for receiving light 20T ... Polygon mirror for projecting light

Claims (2)

[Scope of utility model registration request] 1. Irradiation means for emitting irradiation light; Irradiation light reflecting means for irradiating scanning light with scanning irradiation light by having a plurality of reflecting surfaces and rotating about a rotation axis. A reading device that has a plurality of reflecting surfaces that are deviated by a predetermined angle in the rotation direction with respect to the reflecting surface of the means, and that reflects the reading reflected light from the reading object toward the light receiving means by rotating about the rotation axis A reading device comprising: a reflected light reflection unit; and a light reception unit provided at a position different from the irradiation unit on a plane perpendicular to the rotation axis. 2. An irradiation means for emitting irradiation light, having a plurality of reflecting surfaces which are not parallel to a rotation axis,
Irradiation light reflecting means for irradiating the irradiation light while scanning the irradiation light by rotating about the rotation axis, and having a plurality of reflecting surfaces substantially parallel to the rotation axis, centering on the rotation axis. Read reflected light reflecting means for reflecting the read reflected light from the reading object toward the light receiving means by rotating, and a light receiving means provided at a position different from the irradiating means on a plane including the rotation axis. A reading device characterized by.