JP2005246443A - Method for making square unit cell of two-dimensional code by laser beam exposure device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for making a unit cell of a square shape with the read accuracy higher than heretofore in the case the unit cell shape of the square shape constituting a two-dimensional code is created by an exposure device using a laser beam. <P>SOLUTION: The laser beam exposure device is constituted by successively arranging a laser generator 3, an expander lens 5, an aperture 6" installed side by side with through-holes 6 and 6b of the square shape, a galvanoscanner mirror 7 and an fθ lens 8. The aperture 6" is set at an aperture base 61 in such a manner that the inclination of the through-holes 6a and 6b of the square shape is made approximately equal to the angle of inclination of the revolving axis of the galvanoscanner mirror 7Y on the laser beam incident side. An object 9 is irradiated with the laser beam formed to the square shape in section by the aperture 6" and the galvanoscanner mirror 7 is moved to move a laser beam spot 41" to irradiate the unit cell marking section with the laser beam spot in a way as to smear away the marking section, thereby forming the square shape unit cell. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a creation method for forming a rectangular unit cell constituting a two-dimensional code by a laser exposure apparatus, and an aperture angle adjusting device for an aperture used when the creation method is carried out.

  As is well known, the two-dimensional code 1 as shown in FIG. 1 is formed by arranging rectangular unit cells 2 according to the code configuration of the data code.

  And when marking this square unit cell on a target object with a laser exposure apparatus, conventionally, as shown in FIG. 2, after expanding the laser beam 4 output from the laser generator 3 with the expander lens 5, the circular hole is formed. After being squeezed through the aperture 6 provided, the light is reflected twice by the galvano scanner mirror 7 to change the direction of the light beam from the side to the bottom, incident on the f · θ lens 8, and then the laser beam squeezed by the f · θ lens 8 Is moved to the exposure surface of the object 9, and the galvano scanner mirror 7 is moved so that a spot 4 ″ of a circular laser beam 4 ′ having a diameter approximately half the length of one side of the unit cell size is shown in FIG. As shown by the arrow in FIG. 3, the unit cell 2 ′ having a pseudo-rectangular shape is formed as shown in FIG.

  The same applies when marking is performed by moving the object on the XY table by moving the XY table without scanning the laser beam.

However, since the pseudo-rectangular unit cell 2 ′ is formed by the circular laser beam 4 ′ as described above, the object 9 is compared with the target square as shown in FIG. As shown by the arrow, an unirradiated part is created, so when a reader device reads a two-dimensional code composed of unit cells created by a conventional method, it depends on the illumination conditions that illuminate the reader device and the two-dimensional code. In some cases, 2D codes could not be read.
Japanese Patent Laid-Open No. 2002-160078

  Therefore, the present invention has an object to provide a method of creating a rectangular unit cell with high reading accuracy when a rectangular unit cell constituting a two-dimensional code is created by an exposure apparatus using a laser beam. is there.

  The present invention has been made in order to solve the above-mentioned problems. The first invention is a laser exposure apparatus that uses a two-dimensional code formed by arranging rectangular unit cells on an object in parallel according to the code configuration of a data code. When marking, an aperture provided with a square through-hole so that the spot size of the laser beam on the exposure surface is less than the length of one side of the unit cell size and more than 1/2 is placed behind the expander lens. A rectangular unit cell is formed by irradiating an object with a laser beam shaped into a quadrangular cross section and moving and irradiating the laser beam spot so as to fill a unit cell marking portion. 2D code unit cell forming method.

  According to a second aspect of the present invention, in the case of marking a two-dimensional code in which rectangular unit cells are arranged side by side in accordance with the creation of a data code on an object by a laser exposure apparatus, the length of one side is set on the exposure surface. The laser light spot size was set to be not more than 1/2 of the length of one side of the unit cell size and not less than 1/2, and provided with a short-shaped through-hole having the length of the other side not more than that length. An aperture is provided at the back of the expander lens, the target is irradiated with laser light that has a short cross-section shaped by the aperture, and the laser light spot fills the unit cell marking area to irradiate the rectangular unit cell. A unit cell forming method of a two-dimensional code characterized by forming.

  According to a third invention, in the first or second invention, the laser exposure apparatus is a laser exposure apparatus that moves and irradiates laser light using a galvano scanner mirror, and the aperture through-hole is a galvano scanner on the laser light incident side. This is tilted from the reference by an angle that corrects the deflection of the exposure pattern due to the tilt of the rotation axis of the mirror.

  According to a fourth aspect of the present invention, in the case of marking a two-dimensional code in which rectangular unit cells are arranged side by side in accordance with the code configuration of a data code on a target by a laser exposure apparatus using a galvano scanner mirror, An aperture provided with a diamond-shaped through hole whose spot size of the laser beam on the exposure surface is smaller than the unit cell marking portion, and is inclined from the reference by an angle that corrects the deflection of the exposure pattern according to the shape of the through hole. In addition, a rectangular unit cell is formed by irradiating an object with laser light shaped into a rhombus by the aperture and moving and irradiating the laser light spot so as to fill the unit cell marking portion.

  Note that the laser beam spot moving method in the present invention is such that the laser beam spot fills the unit cell marking portion, for example, according to the cross-sectional shape of the laser beam irradiated to the object, the Z shape, the U shape, It shall be moved in a letter shape.

  A fifth invention relates to an aperture mounting angle adjusting device for creating a unit cell having a simple structure and easy to use for carrying out the present invention, and is provided with a through-hole such as a quadrangle, a rectangle or a rhombus. A vertically long hole for mounting is provided by sandwiching a pin hole in the aperture, the pin hole is engaged with a pin provided in the slide plate, and the aperture is fixed to the slide plate with a screw penetrating the vertical hole for mounting, and An aperture adjustment device for an aperture for creating a unit cell, characterized in that the slide plate is fixed to an aperture base with a screw penetrating a horizontally long mounting hole provided in the slide plate.

  In a laser exposure apparatus that performs marking by moving an XY table or driving a galvano scanner mirror to move a laser beam spot on an object, it is common to use an expander lens to mark a square unit cell. It is conceivable to mark a square unit cell by providing an aperture provided with a through hole in which the spot size of the laser beam on the exposure surface is equal to the size of one unit cell. However, in that case, due to the diffraction phenomenon of light, the marked unit cell has a large R at the four corners, and is likely to cause a reading error.

  In the first invention and the second invention, since the cross section of the laser beam is smaller than the above case, the four corners R of the marked unit cell are reduced, so that a two-dimensional code with less reading error is marked. Can do.

  However, when the first and second inventions are applied using a laser exposure apparatus that uses a galvano scanner mirror, the unit cell is marked with an inclination due to the structure of the galvano scanner mirror. There is. The third invention is a method for solving the problem.

  Here, in order to facilitate understanding, the above-described problem caused by the structure of the galvano scanner mirror will be described.

  FIG. 4 shows a projection state of a laser beam spot when an aperture 6 ′ provided without tilting the square through hole 6a is provided perpendicular to the optical axis of the laser beam. The light is deflected and the exposure pattern is projected with an inclination of θ ° with respect to the Y axis on the object.

  This inclination angle θ ° is equal to the mounting angle θ ° of the rotating shaft of the galvano scanner mirror 7Y on the laser light incident side, and is usually around 20 °.

  Therefore, when the first or second invention is applied, the shape of the marked pseudo-rectangular unit cell is as shown in FIG. 5 (a), and the reference dimension of the unit cell as shown in FIG. 5 (b). Jump out or become lacking. The two-dimensional code is, for example, as shown in FIG.

  The third invention has been made to remedy this problem, and uses an aperture 6 "provided with a square through hole 6a inclined by θ ° as shown in FIG. 6 (a). According to this method, the laser beam spot is not inclined with respect to the Y axis on the object as shown in the figure, and the pseudo-rectangular unit cell that falls within the reference dimensions as shown in FIG. It is possible to realize a high-quality unit cell, that is, a high-quality two-dimensional code.Because the inclination angle θ ° varies depending on the structure of the galvano scanner mirror, the aperture mounting angle can be easily adjusted with an adjustment screw etc. According to a fifth aspect of the present invention, there is proposed an aperture mounting adjusting device having a simple structure.

  In the first to third inventions, the through holes provided in the apertures are square or short, but when using a laser exposure device using a galvano scanner mirror, a practical pseudo-rectangular unit cell can be used as a rhombus. The present invention has been found and the fourth invention has been made.

  FIG. 7 (a) shows the shape of an aperture provided with a diamond-shaped through-hole, the inclination angle θ ° of the rotation axis of the incident-side galvano scanner mirror, and the angle formed by the side of the diamond-shaped through-hole with the vertical axis (diagonal diagonal) FIG. 7B shows the relationship with η °, and FIG. 7B shows the shape of the exposure pattern on the exposure surface. In the fourth invention using an aperture having a diamond-shaped through hole, the one side of the diamond-shaped exposure pattern deflected by the galvano scanner mirror is transparent so that it is parallel to the reference (X axis) as shown in FIG. The holes are inclined.

  However, when the rhomboid shape of the through hole is set so that the angle η ° coincides with the inclination angle θ ° of the rotation axis of the incident side galvano scanner mirror, it is not necessary to incline the rhomboid through hole. That is, in the fourth invention, the position of the through hole is inclined from the reference by an angle for correcting the deflection of the exposure pattern in accordance with the shape of the through hole.

  Of course, in the fourth invention as well, the diamond-shaped through-holes are such that the spot size of the laser beam on the exposure surface is smaller than the unit cell marking part, and at the same time, the unit cell marking part is filled as shown in FIG. As shown, the laser beam spot is moved and irradiated.

  According to this exposure method, as shown in FIG. 7 (d), the size of the reference unit cell (square) can be made as much as possible, and marking a high-quality two-dimensional code practically free from reading errors. can do.

  According to the present invention, it is possible to create a rectangular unit cell with higher reading accuracy than the conventional method.

  FIG. 8 is a schematic diagram showing a configuration of a laser exposure apparatus of an embodiment in which the present invention is applied to marking of a two-dimensional code using a laser exposure apparatus using a galvano scanner mirror. Is an expander lens, 6 "is an aperture provided with two square-shaped through holes 6a and 6b having different sizes as shown in FIGS. 9 and 10, 7 is a galvano scanner mirror, and 8 is an f · θ lens.

  The aperture 6 "is fixed to the aperture base 61 via a slide plate 62, and two large and small quadrilateral through holes 6a and 6b are previously inclined by an inclination angle θ ° of the rotation axis of the galvano scanner mirror 7Y. It has been.

  The aperture 6 "is provided with vertically long mounting holes 64, 64 on both sides of a pin hole 63 provided in the center, and a pin 65 engaged with the pin hole 63 on the slide plate 62, Screw holes 66, 66 having a diameter narrower than the width of the vertical mounting holes 64, 64 and horizontal mounting holes 67, 67 are provided, and the aperture base 61 is further provided with screw holes 68 for mounting the slide plate 62. 68, 68 and mounting holes 69, 69 for attaching the aperture base 61 to the laser exposure apparatus are provided. The aperture 6 "is provided on the slide plate 62, and the slide plate 62 is provided on the aperture base 61 with two screws 70, respectively. It is fixed with. The pin 65 may be provided on the aperture 6 "side, and the pin hole 63 that engages with the pin 65 may be provided on the slide plate 62 side.

  Since it is configured as described above, the aperture 6 "can be moved and adjusted in the horizontal direction within the range of the mounting oblong holes 67, 67 provided in the slide base 67, and has two large and small rectangular through holes. The mounting angle of 6a, 6b can be finely adjusted.

  Accordingly, the laser beam 41 output from the laser generator 3 is enlarged by the expander lens 5 and then passes through an aperture 6 "provided with a square through hole so that the spot size of the laser beam on the exposure surface is a square unit. A quadrilateral smaller than the cell size, that is, a beam having a size such that the length of one side is equal to or shorter than the length of one side of the unit cell size and is a square of 1/2 or more, and the galvano scanner mirror 7, f · θ The object 8 is narrowed down to a square smaller than the size of the unit cell by the lens 8 and irradiated onto the object 9, and as shown in FIG. The unit cell is marked in a square shape as shown in FIG.

  The marked pseudo-rectangular unit cell is a high-quality unit cell with high reading accuracy, although slightly unirradiated portions are formed at the four corners as compared with the target square.

  The shape of the aperture through hole is basically a square, but may be a rectangle or a rhombus as described above. In the case of a rectangle, the length of one side is set to a size such that the spot size of the laser beam on the exposure surface is less than or equal to one side of the unit cell size, and 1/2 or more, and the length of the other side is It shall be below that length.

Note that in order to create a rectangular unit cell, the aperture hole has a side diameter of 82, which is a beam diameter represented by 1 / e ² of the incident laser light beam after passing through the expander lens. Although the effect comes out from shorter than%, it is preferable to make the length about 50 to 70% practically.

  FIG. 12 shows an embodiment of the aperture 6 ′ ″ in the case where the through hole is a diamond shape. The only difference is the shape of the through hole, and the other parts are structurally different from those shown in FIGS. Is the same.

Diagram showing an example of a two-dimensional code Schematic which shows the structure of the laser exposure apparatus using the conventional galvanometer scanner mirror. Explanatory drawing of the conventional method in the case of forming a unit cell with a laser beam. Explanatory drawing which shows the structure and effect | action of a galvano scanner mirror. Explanatory drawing which shows the formation state of the unit cell and two-dimensional code at the time of implementing 1st invention with the laser exposure apparatus using a galvano scanner mirror. Explanatory drawing which shows the formation state of the unit cell and two-dimensional code at the time of implementing 3rd invention with the laser exposure apparatus using a galvano scanner mirror. Explanatory drawing which shows the formation state of the unit cell and two-dimensional code at the time of implementing 4th invention with the laser exposure apparatus using a galvano scanner mirror. Schematic which shows the structure of the laser exposure apparatus used for Example 1 of this invention. The perspective view of the aperture used for Example 1 of this invention. FIG. 10 is an exploded perspective view of the embodiment shown in FIG. 9. FIG. 3 is an explanatory diagram of a unit cell created according to the first embodiment. The perspective view of the aperture used for Example 2 of this invention.

Explanation of symbols

3 Laser Generator 5 Expander Lens 6 Aperture 7 Galvano Scanner Mirror 8 f / θ Lens 9 Object

Claims (5)

When marking a two-dimensional code in which rectangular unit cells are juxtaposed on an object according to the code configuration of the data code by a laser exposure apparatus, the spot size of the laser beam on the exposure surface is one side of the unit cell size. An aperture provided with a square through-hole that has a size of 1/2 or less in length is provided behind the expander lens, and the aperture is used to irradiate the object with laser light shaped into a square cross section. A method for producing a rectangular unit cell of a two-dimensional code, wherein a rectangular unit cell is formed by moving and irradiating a laser beam spot so as to fill a unit cell marking portion. When marking a two-dimensional code in which rectangular unit cells are arranged side by side in accordance with the creation of a data code on an object by a laser exposure apparatus, the spot size of the laser beam on the exposure surface is set to the length of one side. An aperture provided with a short through hole with the length of one side of the unit cell size being equal to or less than 1/2 and the other side being equal to or less than the length is provided behind the expander lens. A rectangular unit cell is formed by irradiating an object with laser light having a short cross section formed by the aperture and moving and irradiating the laser light spot so as to fill a unit cell marking portion. A method for creating a rectangular unit cell of a two-dimensional code. The laser exposure device is a laser exposure device that moves and irradiates laser light using a galvano scanner mirror, and corrects the deflection of the exposure pattern due to the tilt of the rotation axis of the galvano scanner mirror on the laser light entrance side through the aperture. 3. The two-dimensional code quadrilateral unit cell creation method according to claim 1, wherein the angle is inclined from the reference by an angle. When marking a two-dimensional code in which rectangular unit cells are arranged side-by-side in accordance with the code structure of the data code on a target by a laser exposure apparatus using a galvano scanner mirror, the laser beam on the exposure surface is placed behind the expander lens. An aperture with a diamond-shaped through-hole whose spot size is smaller than the unit cell marking part is provided, and the aperture is inclined from the reference by an angle that corrects the deflection of the exposure pattern according to the shape of the through-hole, and the aperture makes the rhombus A method of creating a rectangular unit cell of a two-dimensional code by irradiating an object with shaped laser light and moving and irradiating the laser light spot so as to fill a unit cell marking portion.   A vertically long hole for mounting is formed by sandwiching a pin hole in an aperture provided with a through-hole such as a quadrangle, a rectangle, or a rhombus, and the pin hole is engaged with a pin provided on the slide plate, and the vertical hole for mounting is passed through. The mounting angle of the aperture for creating the unit cell is characterized in that the aperture is fixed to the slide plate with a screw, and the slide plate is fixed to the aperture base with a screw penetrating the mounting elongated hole provided in the slide plate. Adjusting device.

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