JPH08235295A - Laser type optical scanning device - Google Patents

Abstract

(57) [Abstract] [Purpose] By scanning the object to be read several times while swinging the laser beam once, it enables quick and reliable reading work and improves efficiency, and also the width of the main body case. Provided is a laser scanner capable of reading an even wider object to be read. A main body case 10 having a laser beam emitting port 16 at a tip end thereof, and a laser beam generated by a laser light source scans an object to be read, and a laser beam reflected by the object is received by a light receiving section. Of the main body case 10 facing the emission port 16 so that the laser beam from the laser optical unit 20 is photoelectrically converted and the laser beam from the laser optical unit 20 is reflected to irradiate the object to be read with the reflected laser beam. A pair of opposed flat reflecting mirrors 30 and 31 (reflecting members) attached along the inner sides of both sidewalls 18 and 18, and the main body case 10 of the portion facing the emission port 16.
Both side walls 18, 18 of the flat reflecting mirrors 30, 31 or convex reflecting mirrors 40, 41 which are a pair of reflecting members facing the enlarged side wall portions on both sides thereof.
Is attached in an inverted C shape.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a simple portable laser type optical scanning device (hereinafter referred to as a laser scanner) which is used for product identification by scanning an object to be read such as a bar code.

[0002]

2. Description of the Related Art In general, handy type scanners that optically read an object to be read such as a bar code displayed on a product include an object to be read such as a bar code by emitting light from a light emitting element such as a light emitting diode. There is a touch scanner in which an object to be read can be optically read by irradiating an object and receiving reflected light from the object with a light receiving element such as a photodiode. Further, in a laser scanner using a laser beam having a strong directivity, a laser beam generated by a laser light source is emitted while being periodically oscillated with a predetermined amplitude, and is emitted to an object to be read which is apart from the emission port to some extent. A laser beam that is emitted, reflected, and returned is received by a light receiving portion and is read by photoelectrically changing it. 15 and 1
6A and 6B are a plan view and a side view schematically showing a conventional example of a laser scanner. A modularized laser optical unit 2 is built in the case 1 of the scanner body. This laser optical unit 2 is a rotary scanning device that emits a laser beam 3 generated by a laser light source from a front end emission port 4 of a main body case 1 and irradiates and scans an object to be read (not shown) such as a barcode. Means are provided. In this rotary scanning means, the laser beam 3 is swung with a predetermined amplitude in a fan shape from one side to the other side indicated by broken lines 3A and 3B in the figure. Further, the laser optical unit 2 is provided with a light receiving section for receiving and photoelectrically converting the laser beam reflected and returned from the reading object.

[0003]

In such a conventional laser scanner, while the laser beam 3 is swung from one side 3A to the other side 3B in the scanning range 5 shown by the hatched portion in FIG. In contrast, scanning can be performed only once. Therefore, if the reading is incomplete, the scanning is repeated once again, which is inconvenient. Further, even if the scanning range 5 is expanded and an object to be read such as a bar code having a large width is to be read, there is a limit because it is blocked by both side walls of the main body case 1 facing the ejection port 5. Therefore,
A first object of the present invention is to provide a laser scanner in which an object to be read is scanned several times while the amplitude of the laser beam is swung once, thereby enabling a quick and reliable reading operation and improving efficiency. Is. Further, a second object of the present invention is to provide a laser scanner capable of reading an object to be read which is considerably wider than the width of the exit of the main body case.

[0004]

In order to achieve the above-mentioned first object, the laser scanner according to the first and second aspects of the present invention is provided with an emission port for emitting a laser beam to the outside at the tip portion. The main body case and the laser beam generated by the laser light source built into the main body case are periodically shaken at a predetermined amplitude to irradiate the scanning target that is located a distance from the emission port and scan the scanning target. A laser optical unit that receives the reflected and returned laser beam and photoelectrically converts it, and both side walls of the main body case facing the emission port so that the object to be read can be irradiated with the reflected laser beam that reflects the laser beam from the laser optical unit. And a pair of opposing reflecting members attached along the inner side of, and a flat reflecting mirror can be used as the reflecting member. Further, in order to achieve the second object, in the laser scanner according to claims 3 to 5 of the present invention, both side walls of the main body case facing the emission port are formed so as to be enlarged toward the emission port, A pair of opposing reflecting members are attached to the enlarged side wall portions on both sides in an inverted V-shape, and as the pair of opposing reflecting members attached in the inverted C-shape,
Either a flat mirror or a convex mirror can be used. When a convex reflecting mirror is used for the reflecting member, the scanning width for scanning with the reflected laser beam reflected by the convex reflecting mirror of the laser beam from the laser optical unit, with respect to the reading object located at a constant distance from the exit, The convex surface curvature of the convex reflecting mirror is set so as to be the same as the scanning width for scanning with the laser beam directly from the laser optical unit.

[0005]

According to the laser scanner of the present invention, while the laser beam is swung once by the laser optical unit at a predetermined amplitude, the reflected laser beam reflected by the reflecting members on both sides is applied to the object to be read. A total of three scans can be performed: two scans by irradiating and scanning, and one scan by directly irradiating and scanning the object to be read with the laser beam from the laser optical unit without reflection. That is, since scanning can be performed three times by swinging the laser beam once with a predetermined amplitude, the inconvenience of repeating the operation is eliminated and reliable reading is possible. In other words, the work efficiency can be improved by shortening the time required for one reading operation. Further, in the laser scanner according to any one of claims 3 to 5, the main body case is enlarged by enlarging both side walls of the main body case facing the emission port, and the reflecting members are attached to the enlarged side wall portions on both sides thereof in an inverted V shape. It is possible to read an object to be read that is, for example, a barcode that is significantly wider than the width of the case. Either a flat reflecting mirror or a convex reflecting mirror can be used as the reflecting member, and the scanning width can be made larger with the convex reflecting mirror than with the flat reflecting mirror. Also, by using a convex reflecting mirror with a convex curvature set for the reflecting member, and by making the scanning width of the reflected laser beam that is reflected the same as the scanning width of the direct laser beam, a certain distance from the exit It becomes easy to align the position of the reading target object with the laser beam at the time of scanning.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first laser scanner according to the present invention will be described below.
-A 3rd Example is described with reference to FIGS. FIG. 1 is a plan external view of a laser scanner applied commonly to each of the first to third embodiments. The main body case 10 of the scanner is formed as a long and slender upper and lower case that is convenient to carry. In addition, the case 11 is provided with an input unit 12 in which various keys such as ten keys, function keys and trigger keys are arranged, and the read data is displayed transparently by a display panel 13 including a liquid crystal display unit and an electroluminescence display unit. Is also provided. Also, the main body case 1
0 stores a circuit board (not shown) such as an LSI that performs various controls based on an input signal from the key input unit 12 and sends a drive signal to be displayed on the display panel 13, for example. A laser optical unit 20 schematically shown in each of FIGS. 2 and subsequent figures is electrically connected to the circuit board. That is, the laser beam from the laser optical unit 20 is emitted to the outside from the emission port 16 by the nose cap 15 attached to the tip of the body case 10.
By irradiating an object to be read such as the bar code 17 with a laser beam for scanning, and receiving and controlling a reflected laser beam that is reflected by the bar code 17 and returned, the product etc. is identified and displayed on the display panel 13. It can be displayed.

Based on the above structure, FIGS. 2 to 6 show a laser scanner according to the first embodiment of the present invention.
Laser optical unit 2 stored inside the body case 10
As a structural example thereof, reference numeral 0 has a reflecting mirror for reflecting a laser beam generated from a laser light source for convenience, and scanning as a rotary scanning means for periodically oscillating the laser beam from this reflecting mirror at a predetermined amplitude. A mirror 21 is arranged. The laser beam periodically oscillated by the scanning mirror 21 is provided with an emission port 16 provided at the tip of the main body case 10.
The bar code 17 is emitted from a bar code 17 located at an arbitrary position apart from the ejection port 16 and is scanned. Although not shown, the laser optical unit 2
In 0, a light receiving section is provided in front of the scanning mirror 21 at a position where optical path interference does not occur, and the laser beam reflected by the bar code 17 and returning is received by the light receiving section, and photoelectric conversion is possible.

The scanning mirror 21 may be, for example, a mechanism for periodically swinging the end plate to the left and right around an axis of rotation within an angular range θ corresponding to a predetermined amplitude, and is operated by a control signal from the circuit board. . Further, as the light receiving section, an optical lens system for condensing the laser beam reflected and returned from the bar code 17, a photoelectric conversion element for converting the condensed laser beam into an electric signal, for example, a phototransistor,
It can be configured by using either a photodiode or a photocoupler, and when combined with a CCD (charge coupled devic) image sensor or the like, a laser beam reflected by the barcode 17 and returned can be resolved with a predetermined resolution and converted into an electric signal. It is like this. Based on the electric signal, a bar code data such as a product name, a product price, a manufacturing date, etc. is displayed on the display panel 13 by a signal from a circuit board.

In this first embodiment, a pair of opposing flat reflecting mirrors 30 and 31 are attached to both side walls of the front end portion of the main body case 10 as reflecting members which are the gist of the invention.
That is, the main body case 1 of the portion facing the injection port 16 at the tip
On both side walls 18 of No. 0, a plane reflecting mirror 30 on the left side and a plane reflecting mirror 31 on the right side of the drawing are arranged in parallel along the inner surface thereof, with their reflecting surfaces 30a, 31a facing each other. The left and right flat reflecting mirrors 30 and 31 both have the same length L and are flush with the exit port 16. The laser beam oscillated by the scanning mirror 21 provided in the laser optical unit 20 is adjusted to the rear end of the length L of the flat reflecting mirror 30 on the left side from one side of the predetermined amplitude angle θ, and the amplitude angle θ
The other side of is set to match the rear end of the length L of the flat reflecting mirror 31 on the right side.

With the above-described structure, the first embodiment shown in FIG.
~ Operates and acts as in Figure 6. When reading the bar code 17 displayed on a product or the like, the key input unit 12 is turned on to turn on the power and activate the internal equipment. The laser optical unit 20 is turned on by the drive signal, reflects the laser beam generated from the laser light source by the scanning mirror 21, and swings the received laser beam within the range of the amplitude angle θ. First, as the first step, as shown in FIG.
When the scanning mirror 21 starts rotating rightward in the drawing, the laser beam from the laser light source is swung and the left flat reflecting mirror 3
0 is gradually irradiated from the lower end of the length L to the exit end 16 flush with the upper end, that is, from the broken line symbols 22 to 23 in the figure to the plane reflecting mirror 30 once in the angle range represented by the hatched portion a. The laser beam a within this angle range is reflected by the flat reflecting mirror 30 and has a locus represented by a hatched portion A as the first scanning laser beam (reflected laser beam).
To form. The first scanning laser beam A is emitted from the emission port 16 and irradiates the barcode 17, and the first scanning is performed.

Next, as a second step, as shown in FIG. 5, the scanning mirror 21 continues to rotate in the right direction in the figure, and the optical axis of the laser beam is straight and parallel to the longitudinal axis of the main body case 10. Is shaken to the position. That is, when the laser beam is displaced from the reflection range of the left flat reflecting mirror 30 by the angle range represented by the hatched portion B from the broken line symbols 23 to 24 in the figure, the laser beam is left and right flat reflecting mirrors 30, 31. In the state where it is not reflected by any of the above, it is emitted from the emission port 16 as a direct laser beam in the present invention. This direct laser beam irradiates the barcode 17 as the second scanning laser beam B, and the second scanning is performed.

Further, as the third stage, as shown in FIG.
Still further, when the scanning mirror 21 is rotated rightward in the drawing, the laser beam is shaken so that the flat reflecting mirror 31 on the right side is flush with the exit 16 having the length L from the upper end to the lower end, that is, a broken line 24 in the drawing. From 25 to 25, the angle range represented by the shaded portion c is irradiated.
The laser beam c in this angle range is reflected by the flat reflecting mirror 31 to form a third scanning laser beam (reflected laser beam) having a locus represented by a hatched portion C. The third scanning laser beam C is emitted from the emission port 16 and irradiates the bar code 17, and the third scanning is performed.

In this way, the scanning mirror 21 has the amplitude angle θ.
By swinging the range once, that is, while swinging the laser beam from the position on one side indicated by the reference numeral 22 to the position on the other side indicated by the reference numeral 25, by the scanning loci reflected by the left and right flat reflecting mirrors 30 and 31. Amplitude once through the first to third stages of the first and third scanning laser beams A and C and the second scanning laser beam B that directly irradiates the barcode 17 from the emission port 16 without being reflected. Between "3 times"
The barcode 17 will be scanned. This means that it is possible to increase the number of times of scanning the object to be read such as the barcode 17 in a unit time, in other words, it is possible to shorten the time spent for one scanning. As a result, the object to be read can be quickly and surely read, the time spent for scanning and the energy consumption required for operation work can be significantly reduced, and product identification can be efficiently performed.

The first embodiment also has the following advantages. As shown schematically in FIG. 2, the scanning widths of the three-step locus scanning and the direct scanning by the first to third scanning laser beams A to C are the same as those of the exit port 16 of the main body case 10.
The opening width W ₁ can be expanded considerably. As a result, despite being a small scanner,
It becomes possible to read an object to be read such as a bar code 17 having a wide width W _{2 and a} long length.

Next, FIGS. 7 to 10 show a laser scanner according to a second embodiment of the present invention. The parts common to the members shown in the first embodiment are designated by the same reference numerals,
A duplicate description will be omitted. As shown in FIG. 7, this second
In the embodiment, the same shape as the left and right flat reflecting mirrors 30 and 31 used in the first embodiment and the length L, or the length L or more can be used. The pair of left and right flat reflecting mirrors 30 and 31 facing each other are arranged so as to spread out in an inverted V shape toward the tip of the main body case 10. That is, both side wall portions of the main body case 10 facing the injection port 16a are formed as expanded side wall portions 18a, 18a wider than the case width dimension and in an inverted C shape, and the expanded and enlarged side wall portions 18a on both sides are formed. Along the inner surface of 18a, the left flat reflecting mirror 30 and the right flat reflecting mirror 31 are arranged so that
a and 31a are attached so as to face each other.

The operation and action are the same as those in the first embodiment and are shown in FIG.
Corresponds to FIG. 4 of the first embodiment, FIG. 9 corresponds to FIG. 5, and FIG. 10 corresponds to FIG. Also in this case, while the scanning mirror 21 swings the laser beam once within the range of the amplitude angle θ, the first and third scanning laser beams as the reflected laser beam due to the loci reflected by the left and right flat reflecting mirrors 30 and 31. Two scans in which the barcode 17 is scanned by irradiating the barcode 17 with A and C, and a second scan laser beam B which is a direct laser beam from the laser optical unit without being reflected is barcode 1.
One scan is performed by irradiating 7 and scanning is performed, and three scans are performed in three convenient steps. In the second embodiment, the left and right flat reflecting mirrors 30, 31
The injection port 16a is expanded wider than the injection port 16 of the first embodiment by the amount of the expansion of the inverted C-shape. However, when viewed from the entire scanner, the ejection port 16a does not increase in size.
An object to be read such as a wider bar code 17 having a constant distance H can be read. In other words, it is possible to read an object to be read such as the bar code 17 having a width W ₂ which is further away from the ejection port 16a by a distance H than in the case of the first embodiment.

On the other hand, FIGS. 11 to 14 show a laser scanner of a third embodiment according to the present invention, like the second embodiment. The parts common to the members shown in the first and second embodiments are designated by the same reference numerals, and the duplicated description will be omitted. In the third embodiment, both side wall portions of the main body case 10 facing the injection port 16b are formed as expanded side wall portions 18b and 18b which are expanded and curved in an inverted C shape, and the curved expanded side wall is formed. This is a configuration in which convex reflecting mirrors 40 and 41 are attached along the inner curved surfaces of the portions 18b and 18b.

As the convex reflecting mirrors 40 and 41, those having the curvature R of the convex reflecting surfaces 40a and 41a set as follows are used. Similar to the first and second embodiments, the scanning mirror 21
While shaking the laser beam once within the range of its amplitude angle θ,
First and third scanning laser beams A and C as reflected laser beams according to trajectories reflected by the left and right flat reflecting mirrors 30 and 31.
Is applied to the object to be read and scanned, and the second scanning laser beam B, which is a laser beam directly from the laser optical unit without being reflected, is applied to the object to be read and scanned. Scanning is performed three times in three stages for convenience. In this case, the same scanning width W ₃ by the first and third scanning laser beams A and C shown in FIGS. 12 and 14 and the second scanning laser beam A 2 shown in FIG.
Each of the reflecting surfaces 40 of the pair of left and right convex reflecting mirrors 40, 41 has the same length as the scanning width W ₄ by the scanning laser beam B.
The curvatures R of a and 41a are set. By providing such convex reflecting mirrors 40 and 41, the exit port 16b
When the object to be read, such as a barcode, which is located away from the object to be read, can be easily aligned with the scanning width of the object to be read, and the scanning accuracy is improved.
As a result, the operability and work efficiency when reading the product are significantly improved compared to the first and second embodiments. The possible scanning widths W ₃ and W ₄ can be made wider than those in the first embodiment, and can be considerably expanded as compared with the second embodiment.

[0019]

As described above, in the laser scanner according to the present invention, the laser beam is reflected by the pair of reflecting members on both sides, and then the reading object such as a bar code is irradiated and scanned. Therefore, the object to be scanned can be scanned several times while the laser beam is swung once, and the inconvenience of re-reading as in the past can be eliminated and reliable and highly accurate reading becomes possible. It is possible to reduce the labor involved in the reading work, shorten the scanning time, and improve the work efficiency. Further, by enlarging both side walls of the main body case of the portion facing the exit opening in an inverted C shape and providing a reflecting member of either a flat reflecting mirror or a convex reflecting mirror there, without increasing the size of the scanner main body, It is possible to read an object to be read that is significantly wider than the width of the main body case.

[Brief description of drawings]

FIG. 1 is a plan view showing an appearance example of a laser scanner to which each embodiment according to the present invention is applied.

FIG. 2 is a plan sectional view showing a mode of irradiating a scanning object such as a bar code with a laser beam for scanning in the laser scanner of the first embodiment provided with the plane reflecting mirror.

FIG. 3 is a side sectional view of the laser scanner according to the first embodiment.

FIG. 4 is a plan sectional view showing a scanning mode in which a laser beam is reflected by a plane reflecting mirror and is swung in an amplitude direction of a laser beam in the laser scanner of the first embodiment.

FIG. 5 is a plan sectional view showing a mode in which a laser beam that is not reflected is swung in the amplitude direction for scanning in the laser scanner of the first embodiment.

FIG. 6 is a plan sectional view showing a scanning mode in which a laser beam is reflected by a plane reflecting mirror and is swung in an amplitude direction of a laser beam in the laser scanner of the first embodiment.

FIG. 7 is a plan cross-sectional view showing a mode in which a laser beam of a laser scanner according to the second embodiment, which is spread out and provided with a flat reflecting mirror, is irradiated with a laser beam to scan an object to be read such as a barcode.

FIG. 8 is a plan sectional view showing a scanning mode by swinging the laser beam in the amplitude direction by being reflected by an expanding flat reflecting mirror in the laser scanner of the second embodiment.

FIG. 9 is a plan sectional view showing a mode in which a laser beam that is not reflected is swung in the amplitude direction for scanning in the laser scanner of the second embodiment.

FIG. 10 is a plan sectional view showing a scanning mode in which a laser beam of the second embodiment is reflected by an expanding flat reflecting mirror and a laser beam is swung in the amplitude direction.

FIG. 11 is a plan cross-sectional view showing a mode in which a laser beam of a laser scanner according to a third embodiment, which is spread out and provided with a convex reflecting mirror, is irradiated with a laser beam to scan an object to be read such as a barcode.

FIG. 12 is a plan sectional view showing a scanning mode in which a laser beam is reflected by an expanding convex reflecting mirror and is swung in the amplitude direction of a laser beam in the laser scanner of the third embodiment.

FIG. 13 is a plan sectional view showing a mode in which a laser beam that is not reflected is swung in the amplitude direction for scanning in the laser scanner of the third embodiment.

FIG. 14 is a plan cross-sectional view showing a scanning mode in which a laser beam is reflected by an expanding convex reflecting mirror and is swung in the amplitude direction of a laser beam in the laser scanner of the third embodiment.

FIG. 15 is a plan sectional view showing a mode in which a laser beam is irradiated and scanned in a conventional laser scanner.

FIG. 16 is a side sectional view of a conventional laser scanner.

FIG. 17 is a plan sectional view showing a scanning range of a laser beam in a conventional laser scanner.

[Explanation of symbols]

 10 Main Body Case 16 Laser Beam Exit 17 Object to be Read such as Bar Code 18 Case Side Wall 20 Laser Optical Unit 21 Scanning Mirror 22-25 Each Position of Laser Beam Swung in Amplitude Range 30, 31 Planar Reflector (Reflecting Member) 40 , 41 Convex reflector (Reflecting member)

Claims (5)

[Claims] 1. A main body case having an emission port for emitting a laser beam to the outside at a tip portion, and a laser beam generated by a laser light source, which is built in the main body case, is periodically oscillated with a predetermined amplitude. The laser optical unit that irradiates and scans the object to be read at a distance from the emission port, receives the laser beam reflected by the object to be read and photoelectrically converts it, and reflects the laser beam from the laser optical unit. A laser type optical scanning device comprising: a pair of opposing reflecting members attached along the inner sides of both side walls of the main body case facing the emission port so that the object to be read can be irradiated with the reflected laser beam. 2. The laser type optical scanning device according to claim 1, wherein the pair of opposing reflecting members are flat reflecting mirrors. 3. The both side walls of the main body case facing the emission port are formed to be enlarged toward the emission port, and the pair of opposed reflecting members are attached to the enlarged side wall portions on both sides in an inverted V shape. The laser type optical scanning device according to claim 1, wherein 4. The laser type optical scanning device according to claim 3, wherein the pair of opposing reflecting members attached in an inverted V shape are flat reflecting mirrors or convex reflecting mirrors. 5. A laser beam from the laser optical unit for the object to be read which is located at a fixed distance from the emission port, wherein the pair of opposing reflecting members attached in an inverted V shape are convex reflecting mirrors. The scanning width scanned by the reflected laser beam reflected by the convex reflecting mirror is the same as the scanning width scanned by the direct laser beam from the laser optical unit, and the convex curvature of the convex reflecting mirror is set. 5. The laser type optical scanning device according to claim 4, wherein