JP2962439B2 - Beam irradiation reader - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of a beam irradiation reading apparatus, and more particularly to a structure of forming a plurality of irradiation lines of a light beam on an object to be read in order to perform a reliable reading process.

[0002]

2. Description of the Related Art As a beam irradiation reading device, for example, there is a bar code scanner for reading a bar code. As shown in FIG. 3A, the barcode includes a plurality of bars having different thicknesses.
It is composed of a combination of 2B and space 2S,
Represents predetermined data. The bar code scanner performs a reading operation by irradiating the irradiation line L9 on the bar code 2 with a laser beam or the like. That is, the black part of the bar 2B absorbs light, and the white part of the space 2S diffusely reflects light. For this reason, reflected light is generated with the intensity corresponding to the bar code 2, and the reflected light is received by the light receiving element in the bar code scanner to read the bar code 2 and recognize the data.

The following is a method for forming the irradiation line L9 on the bar code 2. First, as shown in FIG. 4A, there is a type in which irradiation light H1 from a semiconductor laser 3 is transmitted through a rod lens 10 via a collimator lens 4. The irradiation light H1 transmitted through the rod lens 10 is linearly enlarged to form an irradiation line L9. The bar code scanner condenses the reflected light H2 from the bar code 2 with a condenser lens 12, receives the light with a line sensor 14 of a CCD, and reads the bar code 2.

[0004] Further, as shown in FIG. 4B, there is a method in which a laser beam is scanned on a bar code 2 in the direction of arrow 90 to form an irradiation line L9. The barcode scanner reflects the irradiation light H1 from the semiconductor laser 3 on the reflection plate 16 via the collimator lens 4 and projects it on the side surface M1 of the polygon mirror 5. The polygon mirror 5 is a polyhedral reflecting mirror, and is controlled to rotate around a mirror axis 5J in the direction of arrow 91.

The irradiation light H1 projected on the side surface M1 of the polygon mirror 5 is reflected here to form an irradiation spot 2P on the bar code 2. At the same time, the polygon mirror 5 rotates by a predetermined angle in the direction of arrow 91, and the irradiation spot 2P scans the barcode 2 in the direction of arrow 90 according to this rotation. Thus, the irradiation line L9 is formed on the bar code 2. The reflected light H2 from the barcode 2 is incident on the side surface M1 of the polygon mirror 5 in a diffused state, is reflected, is collected by the condenser lens 20, and is received by the light receiving section 22.

[0006]

The above conventional beam irradiation reading apparatus has the following problems. For example, as shown in FIG. 3A, a bar 2B has a flaw 2K, and when the irradiation line L9 is located on the flaw 2K, the amount of reflected light changes and accurate reading cannot be performed. If the bar code 2 itself is misaligned, the irradiation light H1 is not irradiated onto the bar code 2 in a distribution process or the like.

For this reason, as shown in FIG. 3B, there is a type in which a plurality of irradiation lines L1, L2, L3, L4, L5, and L6 are formed to perform a reliable barcode reading process (raster scan).
Each of the irradiation lines can be formed by processing the polygon mirror 5 of the barcode scanner in FIG. 4B. That is, each side of the polygon mirror 5 is
It is formed to be inclined at different angles with respect to 5J (not shown). Then, when the polygon mirror 5 is rotated once, the irradiation light H1 reflected from each side surface M1 to M6 is irradiated with the irradiation lines L1, L2, L3, L4, L5, and L5 shown in FIG.
L6 will be formed sequentially.

However, the inclination of the side surface of the polygon mirror 5 requires fine and accurate machining, and there is a problem that a large amount of cost is required for machining the mirror surface of the polygon mirror 5. Further, there is a type in which each side surface is formed by pasting a mirror plate to obtain a desired inclination. However, in this case as well, there is a problem that the pasting operation is troublesome and a large production cost is required. Further, when the irradiation lines L1, L2, L3, L4, L5, L6 are obtained by the inclination of the side surface of the polygon mirror 5,
Since the projection angle of the irradiation light H1 is determined according to each inclination,
There is also a problem that the interval between the irradiation lines cannot be freely changed and adjusted.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a beam irradiation reading apparatus in which a plurality of irradiation lines are formed, and the distance between the irradiation lines can be freely adjusted at a low cost.

[0010]

According to a first aspect of the present invention, there is provided a beam irradiation reading apparatus which emits a light beam toward an object to be read so as to form an irradiation line, and receives light reflected from the object to be read. A deflection member for receiving the light beam emitted by the light-emitting portion, refracting the light beam by a predetermined angle, and irradiating the reading target, and a deflection member that supports the deflection member and generates a movement corresponding to a predetermined voltage. And an adjustment unit that moves and adjusts the irradiation position of the light beam irradiated on the reading target in a direction substantially perpendicular to the irradiation line.

According to a second aspect of the present invention, there is provided a beam irradiation reading apparatus.
A light emitting unit that irradiates a light beam toward the object to be read, a multi-faced member that reflects the light beam emitted by the light emitting unit on its side surface and scans the light beam on the object to be scanned by rotation to form an irradiation line, the object to be read The light receiving unit receives the reflected light from the light emitting unit, the light emitting unit receives the beam light, refracts a predetermined angle, and irradiates the object to be read. An adjustment unit that causes movement, the adjustment unit moving and adjusting the irradiation position of the light beam irradiated on the reading target in a direction substantially perpendicular to the irradiation line is provided.

[0012]

In the beam irradiation reading device according to the first aspect, the deflection member receives the light beam emitted by the light emitting unit, refracts the light beam by a predetermined angle, and irradiates the reading object. The deflecting member is supported by an adjustment unit, which moves in a direction corresponding to a predetermined voltage and moves the irradiation position of the light beam irradiated on the object to be read in a direction substantially perpendicular to the irradiation line. adjust. Therefore, a plurality of irradiation lines can be formed on the object to be read.

In the beam irradiation reading apparatus according to the second aspect, the beam light is reflected on the side surface of the multi-faced member, and scans on the object to be read by the rotation of the multi-faced member to form an irradiation line. Then, the deflection member receives the light beam, refracts the light beam by a predetermined angle, and irradiates the light beam to a reading target. The deflection member is supported by an adjustment unit, and the adjustment unit causes movement corresponding to a predetermined voltage to move and adjust the irradiation position of the light beam irradiated on the reading target in a direction substantially perpendicular to the irradiation line. . Therefore, a plurality of irradiation lines can be formed on the object to be read without forming an inclination on the side surface of the multi-faced member.

Further, in the beam irradiation reading device according to the first or second aspect, the irradiation position of each irradiation line can be arbitrarily determined by adjusting the voltage applied to the adjustment unit.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of a beam irradiation reading apparatus according to the present invention will be described using a bar code scanner as an example. As shown in FIG. 1, irradiation light irradiated by a semiconductor laser 3 which is a light emitting unit
H1 passes through the collimator lens 4 and is converged as parallel light. Then, the irradiation light H1 further passes through the wedge plate 8 as a turning member. The wedge plate 8 is a prism that transmits the received light by refracting the light at a predetermined angle and is made of glass or plastic. By the transmission through the wedge plate 8, the optical path of the irradiation light H1 is changed in the direction of arrow 93 as shown in the figure.

The wedge plate 8 is fixed and supported at the tip 6a of the piezoelectric actuator 6 serving as an adjusting unit. Here, the piezoelectric actuator 6 is an actuator using a piezoelectric element (piezoelectric ceramic, piezoelectric film, or the like), and controls its movement by utilizing the fact that a crystal is distorted according to a given voltage. . The base end 6b of the piezoelectric actuator 6 is fixed to a fixed surface 65, and a lead wire 80 is connected near the base end 6b. By adjusting the voltage applied from this lead wire 80,
The piezoelectric actuator 6 can be moved in the directions of arrows 95 and 96 with a desired amplitude.

When the piezoelectric actuator 6 moves in the direction of the arrow 95, the optical path of the irradiation light H1 changes in the direction of the arrow 93 due to the angle change of the wedge plate 8 accompanying the movement. Conversely, when the piezoelectric actuator 6 moves in the direction of the arrow 96, the optical path of the irradiation light H1 changes in the direction of the arrow 92. Thus, by adjusting the voltage to the piezoelectric actuator 6, the optical path of the irradiation light H1 can be freely controlled, and the irradiation light of a desired angle can be controlled.
H1 can be obtained. In addition, the piezoelectric actuator 6
Excellent responsiveness and high rigidity. For this reason, there is an advantage that the use of the piezoelectric actuator 6 enables quick and accurate control, and also allows the device to be downsized.
In general, the amplitude of the piezoelectric actuator is small and has a limit. However, in order to form each irradiation line on the bar code 2, for example, the maximum deflection angle of 1.35 degrees, 2.43 degrees, 4.86 degrees, or the like is sufficient. For this reason, the limit of the amplitude of the piezoelectric actuator does not particularly hinder the present invention.

This piezoelectric actuator 6, wedge plate 8
Is the mounting position of the barcode scanner in FIG. 4B, for example.
If it is attached to 59 (not shown), the irradiation lines L1, L2, L3, L4, L5, L6 shown in FIG. 3B can be easily obtained.
That is, by adjusting the piezoelectric actuator 6 by voltage control, it becomes possible to perform raster scan without providing each side surface of the polygon mirror 5 with an inclination. The specific operation in this case will be described below.

In FIG. 4B, irradiation light H1 is projected and reflected on the side surface of the polygon mirror 5 to form an irradiation spot 2P on the bar code 2 to be read. The polygon mirror 5 is configured as a polyhedral reflecting mirror, and is controlled to rotate in the direction of arrow 91 about the mirror axis 5J. The direction of the side surface changes due to the rotation of the polygon mirror 5, and accordingly, the irradiation spot 2P on the bar code 2 scans in the direction of arrow 90 to form an irradiation line. The polygon mirror 5 formed as a hexahedron
Is rotated once, six irradiation lines scan on the bar code 2.

Now, it is assumed that the irradiation light H1 is reflected on the side surface M1 of the polygon mirror 5. And the polygon mirror 5
The irradiation spot 2P is scanned by the rotation of
L1 is formed (FIG. 3B). At this time, it is assumed that the piezoelectric actuator 6 and the wedge plate 8 (FIG. 1) are stationary at a predetermined angle in the direction of arrow 95. In FIG. 4B, the rotation of the polygon mirror 5 causes the irradiation light H1 to be subsequently projected on the side surface M2.

At the timing of the conversion of the irradiation surface from the side surface M1 to the side surface M2, the piezoelectric actuator 6 and the wedge plate 8 shown in FIG. Due to the movement of the wedge plate 8, the irradiation line formed by the side surface M2 shifts in the direction of arrow 94 (see FIG. 3B), and the irradiation line
L2 is formed. As described above, if the voltage is changed stepwise for each side surface of the polygon mirror 5 and the piezoelectric actuator 6 and the wedge plate 8 are sequentially moved and controlled, the irradiation lines L1, L2, L3, L4, and L4 shown in FIG. L5 and L6 can be obtained. FIG. 2 shows a stepwise change in the voltage applied to the piezoelectric actuator 6 in this case.

In FIG. 2, if the voltage change period T is adjusted and the amplitude of the piezoelectric actuator 6 is controlled, the intervals between the irradiation lines L1, L2, L3, L4, L5, L6 can be freely controlled and determined. be able to. In addition, the number of irradiation lines can be changed. Furthermore, if the voltage applied to the piezoelectric actuator 6 is fixed, the bar code 2 can be read by forming only a single irradiation line as needed.

In the above embodiment, the bar code scanner shown in FIG. 4B has been described as an example. However, by applying the mechanism of FIG. 1 to the bar code scanner of FIG. 4A, the irradiation lines L1, L2, L3, L4, L5,
L6 may be formed.

[0024]

In the beam irradiation reader according to the first aspect, a plurality of irradiation lines can be formed on the object to be read by adjusting the movement of the irradiation light performed by the adjustment unit. Therefore, as compared with the case where the reading process is performed based on the irradiation of the single irradiation line, the reading process can be performed more reliably without being affected by the displacement of the reading target or the like. In the beam irradiation reading device according to the second aspect, a plurality of irradiation lines can be formed on the object to be read without forming a slope on the side surface of the polyhedral member. Therefore, reliable reading can be performed at low cost.

In the beam irradiation reading device according to the first or second aspect, the irradiation position of each irradiation line can be arbitrarily determined by adjusting the voltage applied to the adjustment unit. Therefore, the interval between the irradiation lines can be freely adjusted, and a reading operation suitable for the size of the reading target and other conditions can be performed. Further, the number of irradiation lines themselves can be arbitrarily determined.
Further, if the voltage applied to the adjustment unit is fixed at a constant value, it is possible to form only a single irradiation line and perform reading if necessary.

[Brief description of the drawings]

FIG. 1 is a side view showing details of a semiconductor laser, a piezoelectric actuator, a wedge plate, and the like of a beam irradiation reader according to one embodiment of the present invention.

FIG. 2 is a graph showing a voltage change applied to the piezoelectric actuator shown in FIG.

FIGS. 3A and 3B are diagrams showing bar codes, in which A shows a case where a single irradiation line is formed, and B shows a case where six irradiation lines are formed; FIGS.

FIGS. 4A and 4B are perspective views showing a conventional barcode scanner, in which A shows an irradiation line formed by a rod lens and B shows an irradiation line formed by using a polygon mirror.

[Explanation of symbols]

 2 ... Barcode 3 ... Semiconductor laser 5 ... Polygon mirror 6 ... Piezoelectric actuator 8 ... Wedge plate L1, L2, L3, L4, L5, L6, L9 ... Irradiation line H1 ... Irradiation light H2 ... Reflection light

Claims (2)

(57) [Claims] 1. A light emitting unit for irradiating a light beam toward an object to be read so as to form an irradiation line, a light receiving unit for receiving reflected light from the object to be read, and receiving a light beam emitted by the light emitting unit at a predetermined angle. A deflection member that refracts and irradiates the object to be read; an adjustment unit that supports the deflection member and generates a movement corresponding to a predetermined voltage; An adjustment unit that adjusts the movement in a direction substantially perpendicular to the irradiation line. 2. A light emitting section for irradiating a light beam to a reading object, and the light beam emitted by the light emitting section is reflected on a side surface thereof, and the light beam is scanned on the reading object by rotation to form an irradiation line. Supports a polyhedral member, a light-receiving unit that receives reflected light from the object to be read, a diverting member that receives the light beam emitted by the light-emitting unit, refracts the light by a predetermined angle, and irradiates the object to be read. An adjustment unit that generates a movement corresponding to the voltage of the light source, the adjustment unit that moves and adjusts the irradiation position of the light beam irradiated on the reading target in a direction substantially perpendicular to the irradiation line. Beam irradiation reader.