JPH11282954A - Laser module and bar code reader - Google Patents

Abstract

PROBLEM TO BE SOLVED: To vertically match the longitudinal direction of an ellipse against the scanning direction of a laser beam even when an elliptical beam form is shaped by fixing a laser beam emitting means and adjusting a base to store the beam emitting means and also the position and direction of the optical axis of an optical element fixing means. SOLUTION: A laser diode 19 is fixed on a base 23, and an optical element holder 22 is housed in a hole 24. Then the holder 22 whose adjusting jig pin 26 is set at a recess 25 is moved in its optical axis direction with an arrow to adjust the position and size of the waist of the laser beam to be generated by adjusting the distance of a lens 20 against the diode 19. Then the holder 22 is turned around its optical axis with an arrow and the section shape of an elliptical laser beam is turned to vertically adjust the longitudinal direction of the elliptical beam against the scanning direction of the laser beam. In such a case, the holder 22 restricts the movements and turns excluding the movement caused toward its optical axis and the turn caused around its optical axis, respectively.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a module including a laser diode and an optical system for condensing and shaping light emitted from the laser diode to generate a laser beam, and is incorporated in a bar code reader and used. Is done.

[0002]

2. Description of the Related Art A conventional technique will be described below with reference to FIGS.

A bar code reader using a laser beam scans a bar code reader 2 with a laser beam 1 and captures a difference between the reflection intensities of a black bar and a white bar of the bar code 2 to generate an electric signal. . The laser beam 1 condenses and shapes the light from the laser diode 3 by an optical system including a lens 4, a stop 5, and the like, and once narrowed down, forms a thinnest portion called a beam waist, that is, a portion with the highest resolution. , Gradually spread again. The laser beam 1 is reflected by the scanning mirror 6 that rotates and forms a fan-shaped scanning pattern 7 and is applied to the bar code 2. The reflected light of the laser beam 1 from the bar code 2 is detected by the light detecting element 8 and converted into an electric signal.

In FIG. 9, reference numeral 9 denotes a laser diode, 10
Is a lens for condensing the light from the laser diode 9, 11
Is an aperture, 12 is an optical element holder for fixing the lens 10 and the aperture 11, 13 is a base on which the laser diode 9 and the optical element holder 12 are mounted, 14 is a hole for receiving the optical element holder 12 provided on the base 13, 15 Is a male thread formed in the optical element holder 12, and 16 is a thread formed in the hole 14 and corresponding to the male thread 15.

In such a configuration, the laser diode 9 is fixed to the base 13, and the optical element holder 12 is rotated in the optical axis direction by rotating the external thread 15 around the optical axis in accordance with the internal thread 16 of the hole 14. The position and the size of the beam waist of the generated laser beam are adjusted by moving and adjusting the distance of the lens 10 to the laser diode 9.

FIG. 10A shows a state in which a laser beam having a circular beam shape is scanned and applied to a bar code. FIG. 10B is a diagram showing a state where a laser beam having an elliptical beam shape is scanned and applied to a barcode.

[0007]

As shown in FIG.
The elliptical beam shape that is elongated in the scanning direction is less susceptible to dirt 17 and chipping 18 in bar code printing than the circular beam shape. However, in the conventional laser diode module, the beam shape is circular, and if the beam
When the shape of the elliptical beam shape is adjusted by 0, when adjusting the position and size of the beam waist of the laser beam,
Since the optical element holder 12 rotates around the optical axis, the lens 10 rotates and the cross-sectional shape of the elliptical laser beam also rotates, so that the longitudinal direction of the ellipse of the beam shape with respect to the scanning direction of the laser beam. It is difficult to adjust vertically.

The present invention solves the above-mentioned problems, and adjusts the position and size of a beam waist of a laser beam, and adjusts the longitudinal direction of an ellipse having an elliptical beam shape to be perpendicular to the scanning direction of the laser beam. It is an object of the present invention to realize a laser diode module capable of performing the above.

[0009]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, a first invention of the present application comprises a laser beam emitting means, and a laser beam emitting means for converging and shaping light emitted from the laser beam emitting means to form an elliptical shape. An optical element for generating a laser beam, cylindrical optical element fixing means for fixing the optical element, a base for fixing the laser beam emitting means, and containing the optical element fixing means, and the optical element fixing means The apparatus is provided with adjusting means for adjusting the position of the means in the optical axis direction and the direction around the optical axis.

According to a second aspect of the present invention, there is provided a laser beam emitting means, an optical element for condensing and shaping light emitted from the laser beam emitting means to generate an elliptical laser beam, and the optical element. And a base for fixing the laser beam emitting means and accommodating the optical element holder, wherein the optical element fixing means is made of a magnetic material.

The third invention of the present application is directed to an optical element for emitting a laser beam, condensing and shaping light emitted from the laser beam emitting means to generate an elliptical laser beam, An optical element fixing means for fixing, a base for fixing the laser beam emitting means, and a housing for fixing the direction of the optical element fixing means around the optical axis so as to adjust the position in the optical axis direction; A configuration is provided that includes means for adjusting the position of the element holder in the optical axis direction.

Further, the fourth invention of the present application is directed to a laser beam emitting means, an optical element for condensing and shaping light emitted from the laser beam emitting means to generate an elliptical laser beam, and the optical element. And a base for fixing the laser diode and fixing the direction of the optical element holder around the optical axis so as to adjustably position the optical element holder in the optical axis direction. The optical element holder is made of a magnetic material.

[0013]

According to the first and second aspects of the present invention, the optical element fixing means can adjust the position in the optical axis direction and the direction around the optical axis independently.

According to the third and fourth aspects of the present invention, when the position of the optical element fixing means is adjusted in the direction of the optical axis, the rotation around the optical axis is restricted. The cross-sectional shape of the laser beam does not rotate with the adjustment of the position and size of the beam waist.

Hereinafter, an embodiment of the present invention according to claim 1 will be described with reference to the drawings. FIG. 1 is a perspective view showing the configuration of the laser diode module according to the present embodiment. In the figure, 19 is a laser diode, 20
A lens 21 for condensing and shaping light emitted from the laser diode 19 to generate an elliptical laser beam;
Is a stop, 22 is a cylindrical optical element holder for fixing the lens 20 and the stop 21, 23 is a base on which the laser diode 19 and the optical element holder 22 are mounted, and 24 is an optical element holder 22 provided on the base 23. A cylindrical hole 25 is a concave portion formed in the optical element holder 22.

In such a configuration, the laser diode 19 is fixed to the base 23, the optical element holder 22 is accommodated in the hole 24, and the pin 26 of the adjusting jig is
By adjusting the distance of the lens 20 to the laser diode 19 by moving the optical element holder 22 in the direction of the arrow A in the optical axis direction, the position and the size of the beam waist of the generated laser beam are adjusted. Further, by rotating the laser beam in the direction of arrow B about the optical axis, the cross-sectional shape of the elliptical laser beam is rotated to adjust the longitudinal direction of the ellipse of the beam shape perpendicular to the scanning direction of the laser beam. At this time, by the fitting of the cylindrical optical element holder 22 and the cylindrical hole 24, the movement and rotation of the optical element holder 22 other than the movement in the optical axis direction and the rotation around the optical axis are restricted.
After the adjustment, the optical element holder 22 and the base 23 are fixed with an adhesive.

Also, as shown in FIG.
2, a projection 27 may be formed, and the position and the orientation of the optical element holder 22 may be adjusted by fitting into a hole 28 of an adjustment jig.

Hereinafter, an embodiment of the present invention according to claim 2 will be described with reference to the drawings. FIG. 3 is a perspective view showing the configuration of the laser diode module according to the present embodiment. In the figure, 29 is a laser diode, 30
Denotes a lens for condensing and shaping light emitted from the laser diode 29 to generate an elliptical laser beam;
Is a stop, 32 is an optical element holder made of a cylindrical magnetic material for fixing the lens 30 and the stop 31, 33 is a base made of a non-magnetic material to which the laser diode 29 and the optical element holder 32 are attached, and 34 is a base 33 It is a cylindrical hole for storing the provided optical element holder 32.

In such a configuration, the laser diode 29 is fixed to the base 33, the optical element holder 32 is housed in the hole 34, and the magnet 35 of the adjusting jig is made of a magnetic material through the nonmagnetic base 33. The distance between the lens 30 and the laser diode 29 is adjusted by moving the optical element holder 32 in the optical axis direction arrow C by magnetic coupling with the optical element holder 32, and the position and size of the beam waist of the generated laser beam In addition, by rotating the laser beam in the direction indicated by the arrow d around the optical axis, the cross-sectional shape of the elliptical laser beam is rotated to adjust the longitudinal direction of the ellipse of the beam shape perpendicular to the scanning direction of the laser beam. At this time, by the fitting of the cylindrical optical element holder 32 and the cylindrical hole 34, the movement and rotation of the optical element holder 32 other than the movement in the optical axis direction and the rotation around the optical axis are restricted. After the adjustment, the optical element holder 32 and the base 33 are fixed with an adhesive.

An embodiment of the present invention according to claim 3 will be described below with reference to the drawings. FIG. 4 is a perspective view showing the configuration of the laser diode module according to the present embodiment. In the figure, 36 is a laser diode, 37
Is a lens for condensing and shaping light emitted from the laser diode 36 to generate an elliptical laser beam;
Is a stop, 39 is a rectangular cylindrical optical element holder for fixing the lens 37 and the stop 38, 40 is a base on which the laser diode 36 and the optical element holder 39 are mounted, and 41 is an optical element holder 39 provided on the base 40. A rectangular tube-shaped hole 42 is a concave portion formed in the optical element holder 39.

In such a configuration, the laser diode 36 is fixed to the base 40, the optical element holder 39 is accommodated in the hole 41, and the pin 43 of the adjusting jig is
By moving the optical element holder 39 to the arrow E in the optical axis direction by adjusting the distance between the lens 37 and the laser diode 36, the position and the size of the beam waist of the generated laser beam are adjusted. . At this time, movement and rotation of the optical element holder 39 other than movement in the optical axis direction are restricted by fitting the rectangular cylindrical optical element holder 39 and the rectangular cylindrical hole 41. After the adjustment is completed, the optical element holder 39 and the base 40 are fixed with an adhesive.

Also, as shown in FIG.
A projection 44 may be formed on 9 and may be configured to be fitted in the hole 45 of the adjustment jig to adjust the position and orientation of the optical element holder 39.

An embodiment of the present invention according to claim 4 will be described below with reference to the drawings. FIG. 6 is a perspective view showing the configuration of the laser diode module according to the present embodiment. In the figure, 46 is a laser diode, 47
Is a lens for condensing and shaping light emitted from the laser diode 46 to generate an elliptical laser beam;
Is an aperture, 49 is a rectangular tube-shaped optical element holder made of a magnetic material for fixing the lens 47 and the aperture 48, 50 is a base made of a non-magnetic material to which the laser diode 46 and the optical element holder 49 are attached, and 51 is a base 50 Is a rectangular cylindrical hole for accommodating the optical element holder 49 provided in.

In such a configuration, the laser diode 46 is fixed to the base 50, the optical element holder 49 is accommodated in the hole 51, and the adjusting magnet 52 is connected to the magnetic optical element via the nonmagnetic base 50. By magnetically coupling with the holder 49 and moving the optical element holder 49 to the arrow in the optical axis direction, the lens 47 for the laser diode 46 is moved.
Is adjusted to adjust the position and size of the beam waist of the generated laser beam. At this time, the fitting and the rectangular tubular optical element holder 49 and the rectangular tubular hole 51 restrict the movement and rotation of the optical element holder 49 other than the movement in the optical axis direction. After the adjustment, the optical element holder 49 and the base 50 are fixed with an adhesive.

FIG. 7 is a perspective view showing a configuration of a laser diode module according to an embodiment of the present invention. In the figure, 53 is a laser diode, 54 is an optical element holder, 55 is a base, 56 is a hole provided in the base 55,
Reference numeral 57 denotes an opening provided on the side surface of the hole 56, and reference numeral 58 denotes a tightening screw.

In such a configuration, after adjusting the position and orientation of the optical element holder 58, the screw 58 is tightened to narrow the opening 57, and the optical holder 58 is sandwiched and fixed by the bending of the hole 56. According to the embodiment shown in FIG. 7, after the adjustment, the screw is tightened to narrow the opening, the optical holder is sandwiched by the bending of the hole, and fixed, whereby the optical element is shrunk when the adhesive is cured. It is possible to prevent the adjusted position of the holder from being shifted, and to fix the holder accurately.

FIG. 8 shows a schematic configuration diagram of a bar code reader using a laser beam. A bar code reader using a laser beam scans a bar code 2 with a laser beam 1 and captures the difference between the reflection intensities of the black bar and the white bar of the bar code 2 to generate an electric signal. Laser beam 1 is
The light from the laser diode 3 is condensed and shaped by an optical system including a lens 4, a stop 5, and the like, and once narrowed down to form a thinnest portion, called a beam waist, that is, the highest resolution, and gradually spread again. To go. The laser beam 1 is reflected by the scanning mirror 6 that rotates and forms a fan-shaped scanning pattern 7 and is applied to the bar code 2. The reflected light of the laser beam 1 from the bar code 2 is detected by the light detecting element 8 and converted into an electric signal. Such a barcode reader is configured using the laser diode module described in the above embodiment of the present invention.

[0028]

According to the first or second aspect of the present invention, the optical element fixing means can adjust the position in the optical axis direction and the direction around the optical axis independently, as in the prior art. With the adjustment of the position and size of the beam waist of the laser beam, the cross-sectional shape of the laser beam does not rotate, and even if the elliptical beam shape is shaped by an optical element, the longitudinal direction of the ellipse is scanned by the laser beam. Can be aligned perpendicular to the direction.

According to the third or fourth aspect of the present invention, when the position of the optical element fixing means is adjusted in the direction of the optical axis, the rotation around the optical axis is restricted. With the adjustment of the position and size of the beam waist of the laser beam, the cross-sectional shape of the laser beam does not rotate, and even if the elliptical beam shape is shaped by the optical element, the optical element is fixed to the optical element holder. If the direction is determined, the longitudinal direction of the ellipse can be made perpendicular to the scanning direction of the laser beam.

[Brief description of the drawings]

FIG. 1 is an external perspective view showing a laser diode module according to an embodiment of the present invention.

FIG. 2 is an external perspective view showing attachment of an optical element holder according to one embodiment of the present invention.

FIG. 3 is an external perspective view showing a laser diode module according to another embodiment of the present invention.

FIG. 4 is an external perspective view showing a laser diode module according to another embodiment of the present invention.

FIG. 5 is an external perspective view showing attachment of an optical element holder according to another embodiment of the present invention.

FIG. 6 is an external perspective view showing a laser diode module according to another embodiment of the present invention.

FIG. 7 is an external perspective view showing a laser diode module according to another embodiment of the present invention.

FIG. 8 is a perspective view showing a schematic configuration of a conventional laser barcode reader.

FIG. 9 is an exploded perspective view showing a conventional laser diode module.

FIG. 10 is an explanatory diagram showing a state in which a laser beam is scanned to irradiate a bar code.

[Explanation of symbols]

 19, 29, 36, 46, 53 Laser diode 20, 30, 37, 47 Lens 21, 31, 38, 48 Aperture 22, 32, 39, 49, 54 Optical element holder 23, 33, 40, 50, 55 Base 24 , 34, 41, 51, 56 holes

 ──────────────────────────────────────────────────の Continued on the front page (72) Inventor Takashi Ichiba 1006 Kadoma Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd.

Claims (8)

[Claims] 1. An optical element for generating a laser beam having an elliptical shape by condensing and shaping light emitted from the laser beam emitting means, and an optical element fixing means for fixing the optical means. A base for fixing the laser beam emitting means, and accommodating the optical element fixing means, and adjusting means for adjusting the position of the optical element fixing means in the optical axis direction and the direction around the optical axis. A laser module characterized in that: 2. An optical element for converging and shaping light emitted from the laser beam emitting means to generate an elliptical laser beam, and an optical element fixing means for fixing the optical element. And a base for fixing the laser beam emitting means and accommodating the optical element fixing means, wherein the optical element fixing means is made of a magnetic material. 3. An optical element for converging and shaping light emitted from the laser beam emitting means to generate an elliptical laser beam, and an optical element fixing means for fixing the optical element. Means for fixing the laser beam emitting means, and fixing the direction around the optical axis of the optical element fixing means so as to adjustably position the optical element in the optical axis direction; and the optical axis of the optical element fixing means. A laser module comprising: means for adjusting a position in a direction. 4. An optical element for converging and shaping light emitted from the laser beam emitting means to generate an elliptical laser beam, and an optical element fixing means for fixing the optical element. And a means for fixing the laser beam emitting means, and for fixing the direction of the optical element holder around the optical axis so as to adjustably position the optical element holder in the optical axis direction. A laser module comprising a magnetic material. 5. A laser beam emitting means, an optical element for converging and shaping light emitted from the laser beam emitting means to generate an elliptical laser beam, and a cylindrical optical element for fixing the optical element. Element fixing means, a base for fixing the laser beam emission, and accommodating the optical element fixing means, and adjusting means for adjusting the position of the optical element fixing means in the optical axis direction and the direction around the optical axis. Barcode reader having a laser module to perform. 6. A laser beam emitting means, an optical element for condensing and shaping light emitted from the laser beam emitting means to generate an elliptical laser beam, and an optical element fixing means for fixing the optical element And a base for fixing the laser beam emitting means and accommodating the optical element fixing means, wherein the optical element fixing means has a laser module made of a magnetic material. 7. An optical element for converging and shaping light emitted from the laser emitting means to generate an elliptical laser beam, and an optical element fixing means for fixing the optical element. Means for fixing the laser beam emitting means, and fixing the direction of the optical element holder around the optical axis to accommodate the position in the optical axis direction so as to be adjustable; and A bar code reader having a laser module comprising: means for adjusting a position. 8. A laser beam emitting means, an optical element for condensing and shaping light emitted from the laser emitting means to generate an elliptical laser beam, and an optical element fixing means for fixing the optical element. Means for fixing the laser beam emitting means, and fixing the optical element fixing means in a direction around the optical axis so that the position in the optical axis direction can be adjusted, and the optical element fixing means is magnetic. A bar code reader having a laser module consisting of a body.