JP2002323318A - Positioning method using laser beam and positioning device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a positioning method and a positioning device using laser beam for lengthening the in which a position can be found by using interference fringes of light positively. SOLUTION: In this positioning device 1 using laser beam, when a laser beam is emitted from a laser light source 2, the laser beam is cast on an irradiation object 4 via a spherical lens 3 arranged on an optical axis 6. The face on the irradiation object 4 side of the spherical lens 3 is sphere, so that concentric interference fringes are formed on the irradiation object 4. As these interference fringes are formed by spherical aberration of the spherical face of the spherical lens 3, their intensity is higher than light intensity of interference fringes formed by using an aspherical lens. Therefore, the specification of the center of the interference fringes during positioning work of the irradiation object 4, that is, specification of the center of the optical axis 6 during the work can be facilitated. In addition, the laser beam passing through the spherical lens 3 forms the high-intensity interference fringes, so that this device can withstand use even for a long distance.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a positioning method using a laser beam and a positioning device using a laser beam for specifying the position of an object using the laser beam. The present invention relates to a method and apparatus for examining a deviation between a substrate transport rail surface and a horizontal reference plane, and examining an inclination of a manufacturing apparatus with respect to a vertical direction.

[0002]

2. Description of the Related Art Japanese Patent Application Laid-Open No. 7-167655 discloses a positioning device using a laser beam. This device emits laser light having a horizontal optical axis from a laser light source, and rotates the laser light source about a vertical axis, thereby enabling leveling of a wall surface to be irradiated. In general, a positioning device using laser light described in this publication generally uses a condensing lens to spot the light beam of the laser light on an irradiation target in order to prevent the beam diameter from expanding due to the divergence of the laser light. Focused. As shown in FIG. 7, an aspheric lens 102 is used as a condenser lens in order to positively eliminate the occurrence of light interference fringes and to enhance the concentration of laser light. Even when the aspherical lens 102 is used, light interference fringes slightly occur due to the influence of the end surface of the lens as shown by the broken line.

[0003]

However, when a spot-like laser beam is generated by the aspheric lens 102 and the position of the irradiation target 103 is determined by the spot light, the focal length is limited to several meters. is there. Therefore, for example, in a component mounting machine of an electric board mounting factory,
In the case where the board transfer rails are arranged horizontally for the purpose of smooth transfer of the board, a horizontal reference over a long distance of 20 to 30 meters or more is required,
It was practically impossible to use a conventional device as a reference for such positioning. It is also conceivable to extend the focal length to a sufficient length by using a telephoto lens, but this leads to an increase in the size of the apparatus. As a positioning device using a laser beam, Japanese Patent Application Laid-Open No. Hei 7-21826 is used.
This device is disclosed in Japanese Patent Application Publication No. JP-A-2005-115, and has a variable focal length.

Therefore, the present invention has been made to solve the above-mentioned problems, and uses a laser beam whose distance that can be located is made longer by positively utilizing interference fringes of light. It is an object to provide a positioning method and a positioning device.

[0005]

According to the present invention, there is provided a positioning method using a laser beam, wherein a concentric interference fringe of a laser beam formed on an irradiation object by a spherical aberration of a spherical lens is used to form an interference fringe. The position of the irradiation target is determined by specifying the center.

In the positioning method using laser light according to the present invention, concentric interference fringes are formed on an irradiation target irradiated with laser light through a spherical lens. This interference fringe is formed by the spherical aberration of the spherical lens. However, an aspheric lens used in a conventional condenser lens is designed so that spherical aberration is extremely small, and no interference fringes due to spherical aberration are formed on an irradiation target. Therefore, the light intensity of the interference fringes formed on the irradiation target is higher when the spherical lens is used than when the aspheric lens is used. in this way,
The use of such interference fringes, which actively form high-intensity interference fringes, makes it easy to identify the center of the interference fringes when locating the irradiation target, that is, the center of the optical axis during the work. It is to be. Further, since the laser light passing through the spherical lens forms high-intensity interference fringes, it can withstand use even over long distances, and can be used widely.

A positioning device using laser light according to the present invention comprises a horizontal laser light source for emitting horizontal laser light having an optical axis in a horizontal direction, and a horizontal laser light disposed on the optical axis of the horizontal laser light. A lens for the horizontal laser beam, and the surface of the lens for the horizontal laser beam on the irradiation object side is a spherical surface.

In the positioning device using laser light according to the present invention, when a horizontal laser light having a horizontal optical axis is emitted from a horizontal laser light source, the horizontal laser light is transmitted to a horizontal laser light disposed on the optical axis. Irradiation is performed on the irradiation target object via the laser light lens. Here, since the surface of the horizontal laser light lens on the irradiation object side is a spherical surface, concentric interference fringes are formed on the irradiation object. This interference fringe is formed by the spherical aberration of the spherical surface of the horizontal laser light lens. However, an aspheric lens used in a conventional condenser lens is designed so that spherical aberration is extremely small, and no interference fringes due to spherical aberration are formed on an irradiation target. Therefore, the light intensity of the interference fringes formed on the irradiation target is higher when the spherical lens is used than when the aspheric lens is used. As described above, the use of such interference fringes, which actively formed high-intensity interference fringes, can be used to identify the center of the interference fringes during the leveling operation of the irradiation target, that is, the center of the optical axis during the operation This facilitates the identification of Further, the laser light passing through the horizontal laser light lens forms high-intensity interference fringes,
It can withstand its use even over long distances, and enables wide use.

A positioning device using a laser beam according to the present invention comprises: a vertical laser light source for emitting a vertical laser beam whose optical axis is a vertical direction; and a vertical laser disposed on the optical axis of the vertical laser beam. The vertical laser light lens has a spherical surface on the irradiation object side.

In the positioning device using laser light according to the present invention, when a vertical laser light having a vertical optical axis is emitted from a vertical laser light source, the vertical laser light is transmitted to a vertical laser disposed on the optical axis. Irradiation is performed on the irradiation target object via the laser light lens. Here, since the surface of the lens for vertical laser light on the irradiation object side is spherical, concentric interference fringes are formed on the irradiation object. This interference fringe is formed by the spherical aberration of the spherical surface of the vertical laser light lens. However, an aspheric lens used in a conventional condenser lens is designed so that spherical aberration is extremely small, and no interference fringes due to spherical aberration are formed on an irradiation target. Therefore, the light intensity of the interference fringes formed on the irradiation target is higher when the spherical lens is used than when the aspheric lens is used. In this way, the use of such interference fringes, which actively formed high-intensity interference fringes, is used to identify the center of the interference fringes during the vertical projecting operation of the irradiation target, that is, the center of the optical axis during the operation. This facilitates the identification of Furthermore, the laser light passing through the vertical laser light lens forms high-intensity interference fringes,
It can withstand its use even over long distances, and enables wide use.

In addition, a positioning device using laser light according to the present invention includes a horizontal laser light source that emits horizontal laser light having an optical axis in a horizontal direction, and a horizontal laser light source that is disposed on the optical axis of the horizontal laser light, and A lens for horizontal laser light whose surface on the object side is spherical, a vertical laser light source that emits vertical laser light whose optical axis is vertical, and a surface on the object side that is arranged on the optical axis of the vertical laser light And a vertical laser beam lens having a spherical surface.

In the positioning apparatus using laser light according to the present invention, when a horizontal laser light having a horizontal optical axis is emitted from a horizontal laser light source, the horizontal laser light is transmitted to a horizontal laser light disposed on the optical axis. Irradiation is performed on the irradiation target object via the laser light lens. Here, since the surface of the horizontal laser light lens on the irradiation object side is a spherical surface, concentric interference fringes are formed on the irradiation object. This interference fringe is formed by the spherical aberration of the spherical surface of the horizontal laser light lens. Therefore, the light intensity of the interference fringes formed on the irradiation target is higher when the spherical lens is used than when the aspheric lens is used. As described above, the use of such interference fringes, which actively formed high-intensity interference fringes, is used to identify the center of the interference fringes during the leveling operation of the irradiation target, that is, the center of the optical axis during the operation. This facilitates the identification of Further, since the laser beam passing through the horizontal laser beam lens forms high-intensity interference fringes, it can withstand its use even over long distances, and can be used widely. Similarly, when a vertical laser light having a vertical optical axis is emitted from a vertical laser light source, the vertical laser light is irradiated onto an irradiation target via a vertical laser light lens disposed on the optical axis. Is done. Here, since the surface of the lens for vertical laser light on the irradiation object side is spherical, concentric interference fringes are formed on the irradiation object. Therefore, it is possible to perform the horizontal work and the vertical work at the same time. Note that it is also possible to use one laser beam for positioning and use the other laser beam separately for reference positioning.For example, after specifying a reference position by vertical laser light, the reference position is determined. Originally, it is possible to perform the leveling operation using the horizontal laser light. As described above, since the positioning device using laser light emits laser light in two directions, extremely high versatility is realized.

It is preferable that the apparatus further comprises a support shaft extending perpendicularly to a vertical axis passing through the center of gravity, and a pendulum structure having the support shaft as a center of rotation. In this case, it is easy to always install the positioning device using the laser beam in the vertical direction.

Further, it is preferable that the center of gravity of the weight portion is arranged on a vertical axis passing through the center of gravity. In this case, it is possible to improve the stability when a positioning device using a laser beam having a pendulum structure is installed.

Further, it is preferable that a battery accommodating portion for accommodating the battery is further provided. In this case, electric power is supplied to the positioning device by the battery, and the positioning device using laser light can be of a handy type, so that handling is remarkably improved.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of a positioning device using laser light and a positioning method using laser light according to the present invention will be described below in detail with reference to the accompanying drawings.

First, a first embodiment of a positioning device using a laser beam according to the present invention will be described. As shown in FIG. 1, in a positioning device 1 using laser light, an irradiation object 4 (for example, a wall or a scale of a building) is placed on an optical axis 6 of a laser light source 2 having a semiconductor laser element that emits visible light. Attached ruler) is arranged. Therefore, the laser light is projected on the irradiation surface 5 on the irradiation target 4. A spherical lens 3 is arranged between the laser light source 2 and the irradiation target 4. In the spherical lens 3, the surface on the irradiation object 4 side is a spherical surface, and the surface on the laser light source 2 side is a flat surface. Therefore, the laser beam passing through the spherical lens 3 projects concentric interference fringes around the optical axis 6 on the irradiation surface 5 on the irradiation target 4. This interference fringe is formed by the spherical aberration of the spherical lens 3. In FIG. 1, a bright ring (bright portion) of the interference fringe is formed at the intersection of the optical paths indicated by the solid lines, and has a concentric shape centered on the intersection with the optical axis 6 on the irradiation surface 5. I have. Further, as can be seen from FIGS. 1 and 4, the interference fringes are formed unless the distance from the lens is extremely close (about 0.5 m).

As shown in FIG. 1, when the laser light is emitted from the laser light source 2, the emitted laser light passes through the spherical lens 3 and is irradiated on the irradiation surface 5 of the irradiation object 4. The light image of the laser beam formed on the irradiation surface 5 appears as clear concentric interference fringes because it passes through the spherical lens 3 having a large spherical aberration. Then, the center is specified by using the concentric interference fringes. As a method of specifying the center point of the interference fringe, a method of measuring the irradiation surface 5 on which the interference fringe is formed with a ruler or the like to specify the center point, or a method of writing a reference point on the irradiation surface 5 and There is a method of specifying a center point by superimposing interference fringes. As described above, by using such interference fringes in which high-intensity interference fringes are positively formed, it becomes easy to identify the center of the interference fringes during operation, that is, to identify the center of the optical axis. Therefore, interference fringes are located (for example, horizontal or vertical).
It can be used as a standard for

Here, the relationship between the projection distance from the laser light source 2 to the irradiation surface 5 and the interference fringe will be described. As shown in FIG. 4, when the projection distance is changed in the range of 0.5 to 25 m, the light intensity and the pitch of the interference fringes change accordingly. To explain this change more specifically, the case where the projection distance is 6 m (see FIG. 5) and the case where the projection distance is 25 m (see FIG. 6)
This will be described with an example. 5 and 6, the horizontal axis represents the distance from the optical axis 6 and the vertical axis represents the light intensity. The upper part of the graph shows a part of the interference fringes formed on the irradiation surface 5 in the lower part. It is shown corresponding to the distance from the axis 6. Also,
The bright and dark rings of the interference fringes are schematically shown, and the shorter the width of the ring, the clearer the light and dark.

As shown in the graph of FIG.
The intensity distribution in the case of m clearly shows that the light intensity becomes the highest at the position where the horizontal axis is 0 (the position of the optical axis 6). Then, a peak value is periodically generated in a symmetrical relationship about the position of 0, and a bright ring forms a narrow interference fringe. On the other hand, as shown in the graph of FIG.
As in the case of the projection distance of 6 m, the peak value periodically occurs in a left-right symmetric relationship with respect to the position of 0 as in the case of the projection distance of 6 m. In comparison, the intensity of the light intensity is gentle, and the distance between the peak values is long. Therefore, the width of the bright ring is wider than that of the bright ring when the projection distance is 6 m. However, even with an interference fringe formed at a position where the projection distance is 25 m,
Since the width of the light ring is about 0.5 mm, sufficient accuracy required for positioning is maintained, which indicates that positioning can be performed using interference fringes even at long distances, that is, 25 m. I have.

On the other hand, as shown in FIG. 7, in a positioning device 100 using a conventional laser beam, the laser beam condensed through an aspheric lens 102 designed to have a very small spherical aberration is emitted. Then, one point on the irradiation surface 104 of the irradiation target 103 is irradiated in a spot manner. for that reason,
The optical paths shown by the solid lines do not intersect, and no interference fringes due to spherical aberration are formed on the irradiation surface 104. Note that a slight interference fringe is formed on the irradiation surface 104 due to the light path diffracted at the end of the aspherical lens 102 shown by the broken line. However, since this interference fringe has a lower light intensity than the above-described interference fringe due to spherical aberration, it is formed on the irradiation target using a spherical lens as compared with the case using an aspherical lens. The light intensity of the interference fringes increases. Therefore, when an aspherical lens is used, the shape, outline, and the like of the interference fringes formed on the irradiation target become unclear, and it is difficult to specify the center point of the interference fringes. It cannot be used. As a result, it is difficult to position using the interference fringes.

Next, the positioning device 1 using the laser beam according to the first embodiment more specifically will be described.
0 will be described. The same or equivalent components are denoted by the same reference numerals, and redundant description will be omitted.

As shown in FIG. 2, the positioning device 10 using a laser beam has a pendulum structure, and the center of rotation of the pendulum is a support shaft 13. The support shaft 13 is horizontally supported by an edge of an opening 12a provided in the installation plate 12, and the installation plate 12 is bridged between two transport rails 11 used for transporting a substrate. I have. A rod end 14 is attached to the support shaft 13, and a main body 15 having a size that does not contact the transport rail 11 is fixed to a lower portion of the rod end 14. A vertical laser light generator 1B for irradiating laser light in the vertical direction is provided at a lower portion of the main body 15, and the vertical laser light generator 1B has a vertical laser light source 2B and a floor surface 5B which is an irradiation surface has a spherical surface. Is provided with a vertical laser beam lens 3B. Also, the optical axis 6 of the vertical laser light emitted from the vertical laser light source 2B
The vertical laser light generating unit 1 is arranged so that B coincides with the vertical direction.
The position of B is adjusted by the screw 21 for adjusting the vertical axis. Note that the vertical laser light generator 1B applies the positioning device 1 shown in FIG. 1, and a description thereof will be omitted.

A horizontal laser light generator 1A for irradiating laser light in the horizontal direction is provided above the support shaft 13. The horizontal laser light generator 1A is connected to a main body via a connecting portion 24. 15. The horizontal laser light generator 1A includes a horizontal laser light source 2A and a wall surface 5A as an irradiation surface.
A horizontal laser beam lens 3A having a spherical side is provided. The position of the horizontal laser light generator 1A is adjusted by the horizontal axis adjusting screw 22 so that the optical axis 6A of the horizontal laser light emitted from the horizontal laser light source 2A coincides with the horizontal direction. Note that the horizontal laser light generator 1A employs the positioning device 1 shown in FIG. 1 similarly to the vertical laser light generator 1B, and a description thereof will be omitted.

On the other hand, a cylindrical weight portion 16 is fixed to the main body portion 15 with a weight adjusting screw 17, and the weight portion 16 improves the stability of the positioning device 10 against vibration. The position of the center of gravity of the weight portion 16 is on a vertical axis passing through the center of gravity of the positioning device 10. Further, the main body 15 includes an electric circuit 18 for controlling the laser output and controlling the temperature / time. A battery housing 19 is provided below the electric circuit 18.
Is set. In this way, the battery 2
By using 0, the positioning device 10 becomes a handy type, and portability is improved. Further, the main body 15
The laser switches 23a and 23b of each of the laser light sources 2A and 2B and a circuit switch (not shown) for the electric circuit 18 are provided below.

Next, a positioning method using the above-described positioning device 10 will be briefly described with reference to the drawings. The vertical laser light source 2B is adjusted in advance so that the optical axis 6B is vertical by the vertical axis adjustment screw 21, and the horizontal laser light source is similarly adjusted by the horizontal axis adjustment screw 22 so that the optical axis 6A is horizontal. 2A has been adjusted.

First, the positioning device 10 is installed in the vertical direction by placing the support shaft 13 at a predetermined position on the installation plate 12. Next, a circuit switch (not shown) is turned on, and power is supplied from the battery 20 to the electric circuit 18 to prepare for laser light emission. Subsequently, the laser switches 23a and 23b are turned on, and the horizontal laser light source 2A is turned on.
And a laser beam is emitted from the vertical laser light source 2B. The horizontal laser light whose optical axis 6A is horizontal is converted into a horizontal laser light source 2A.
, A concentric interference fringe is projected onto the wall surface 5A via the horizontal laser light lens 3A disposed on the optical axis 6A. Then, the operator specifies the center of the interference fringes, that is, the center of the optical axis 6A, and performs marking on the wall surface 5A.

Further, the position of the positioning device 10 is changed along the transport rail 11, and the center of the optical axis 6A is similarly marked from the concentric interference fringes projected on the wall surface 5A. By measuring the distance of the mark written on the wall surface 5A in this way, the relative height difference between the initial position of the positioning device 10 and the position after the movement can be measured. Therefore, by changing the position of the positioning device 10 on the transport rail 11 and repeatedly performing the same measurement, the inclination and undulation of the transport rail 11 are detected, and based on that, the horizontal adjustment of the transport rail 11 can be performed. It becomes possible.

Further, a linear reference thread (not shown) is provided on the floor 5B, and the vertical laser light emitted from the vertical laser light source 2B is irradiated. Since the irradiated vertical laser light forms interference fringes on the floor 5B, the position of the optical axis 6B on the floor 5B can be easily specified using the interference fringes as described above. Therefore, the straightness of the transport rail 11 can be measured by measuring the deviation between the optical axis 6B and the reference yarn using a ruler or the like.

Since the positioning device 10 using the laser light includes the horizontal laser light generator 1A and the vertical laser light generator 1B, one of the laser lights is used for positioning by switching the switches 23a and 23b. It is also possible to use the other laser light separately for reference positioning. For example, the switch 23b is turned on, and after confirming that the optical axis 6B of the vertical laser light overlaps the reference thread, the switch 23a is turned on, and the leveling operation can be performed by the horizontal laser light. Thus, it is also possible to use the horizontal laser light and the vertical laser light separately.

Next, a description will be given of a second embodiment of a positioning device using a laser beam according to the present invention. As shown in FIG. 3, the positioning device 30 using laser light according to the second embodiment is positioned at a point where a spherical lens 31 having both spherical surfaces is disposed on the optical axis 6 of the laser light source 2. Different from the device 1.

That is, in the positioning device 30, similarly to the positioning device 1, the laser light emitted from the laser light source 2 is applied to the irradiation surface 5 of the irradiation object 4 after passing through the spherical lens 31. The laser light passing through the spherical lens 31 having both spherical surfaces forms concentric interference fringes on the irradiation surface 5 due to spherical aberration, similarly to the spherical lens 3 having only one spherical surface used in the first embodiment. Form. Then, by specifying the center of the concentric interference fringes by the above-described method or the like, the optical axis 6 of the laser beam is specified and used as a reference for positioning.

The present invention is not limited to the above embodiment, and various modifications are possible. For example, the irradiation target 4 is not limited to a fixed one such as a wall or a floor, and may be a portable one such as a ruler with a scale as long as it can project a laser beam. Further, the laser light source is not limited to a semiconductor laser light source, and may be a gas laser, a solid laser, or the like as long as a desired projection distance can be obtained. Furthermore, what is located is not limited to the transport rail, but may be a building or the like.

[0034]

According to the positioning method using laser light according to the present invention, the center of the interference fringes is specified from the concentric interference fringes of the laser light formed on the irradiation object by the spherical aberration of the spherical lens. By performing the positioning of the irradiation target by using the optical interference fringes, it is possible to positively use the interference fringes of light to increase the distance that can be positioned.

Further, a positioning device using laser light according to the present invention includes a laser light source for emitting laser light, and a laser light lens disposed on the optical axis of the laser light. Since the surface on the side of the object to be irradiated is spherical, it is possible to positively use the interference fringes of light to increase the distance that can be located.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a first embodiment of a positioning device using laser light according to the present invention.

FIG. 2 is a more specific example of a positioning device using the laser light shown in FIG. 1 schematically shown;

FIG. 3 is a schematic diagram showing a second embodiment of a positioning device using laser light according to the present invention.

FIG. 4 is a graph showing a change in light intensity of interference fringes at a projection distance of laser light.

5A and 5B are a graph and a schematic diagram illustrating a state of interference fringes when a projection distance of a laser beam is 6 m.

6A and 6B are a graph and a schematic diagram showing a state of interference fringes when a projection distance of a laser beam is 25 m.

FIG. 7 is a schematic view of a conventional positioning device using laser light.

[Explanation of symbols]

1,10,30 ... Positioning device using laser light, 2,
2A, 2B: laser light source, 3, 3A, 3B, 31: spherical lens, 4: irradiation object, 5, 5A, 5B: irradiation surface,
6, 6A, 6B: optical axis, 13: support shaft, 16: weight part,
19: battery housing, 20: battery.

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[Procedure amendment]

[Submission date] May 23, 2001 (2001.5.2)
3)

[Procedure amendment 1]

[Document name to be amended] Drawing

[Correction target item name] Fig. 5

[Correction method] Change

[Correction contents]

FIG. 5

Claims (7)

[Claims] 1. The method according to claim 1, wherein a center of said interference fringe is specified from a concentric interference fringe of a laser beam formed on the irradiation object by a spherical aberration of the spherical lens, and the irradiation object is located. Positioning method using a laser beam. 2. A horizontal laser light source, comprising: a horizontal laser light source that emits horizontal laser light having an optical axis in a horizontal direction; and a horizontal laser light lens disposed on the optical axis of the horizontal laser light. Wherein the surface on the irradiation object side is a spherical surface. 3. A vertical laser light source, comprising: a vertical laser light source that emits a vertical laser light having a vertical optical axis, and a vertical laser light lens disposed on the optical axis of the vertical laser light. Wherein the surface on the irradiation object side is a spherical surface. 4. A horizontal laser light source that emits horizontal laser light having an optical axis in a horizontal direction, and a lens for horizontal laser light that is disposed on the optical axis of the horizontal laser light and has a spherical surface on an object to be irradiated side. A vertical laser light source that emits a vertical laser light whose optical axis is in a vertical direction, and a vertical laser light lens that is disposed on the optical axis of the vertical laser light and has a spherical surface on the irradiation object side. A positioning device using a laser beam. 5. The pendulum structure according to claim 2, further comprising a support shaft extending perpendicularly to a vertical axis passing through the center of gravity, and having a pendulum centered on said support shaft. A positioning device using the laser beam according to claim 1. 6. The positioning device using laser light according to claim 5, wherein the center of gravity of the weight portion is arranged on a vertical axis passing through the center of gravity. 7. The positioning device using laser light according to claim 2, further comprising a battery accommodating portion accommodating a battery.