JP2002009497A - Illuminating equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a small and low-cost illuminating equipment which efficiently illuminates a board mark of different characteristics for precision positioning the board mark. SOLUTION: A board mark 5 is coaxially and vertically illuminated with a prism pipe 2 of a hollow pipe where the perimeter of one end is formed as a reflective surface 2a, while that of the other end formed as a diffusion surface 2b and light flux from a lighting source 3a incident on the reflective surface is allowed to exit as diffused light from the other end part. Another lighting source 6a is so provided that the board mark is lit diagonally from above. Both coaxial vertical illumination and diagonal illumination are used simultaneously, or, any one of them is used according to reflection characteristics of the board mark to illuminate the board mark, thus a small and efficient illuminating equipment is provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lighting device, and more particularly, to a lighting device for illuminating a position recognition board mark provided on a board on which electronic components are mounted.

[0002]

2. Description of the Related Art In a component mounting apparatus for mounting an electronic component at a predetermined position on a circuit board, if the mounting position is shifted from a reference position, accurate component mounting cannot be performed. A substrate mark for recognition is provided, and the position of the substrate is recognized by imaging the substrate mark to recognize the position.

When recognizing the board mark, there are board marks having various reflection characteristics. In order to recognize these board marks with high accuracy, the board mark is directly applied in accordance with the reflection characteristics of the board mark. Coaxial epi-illumination, which illuminates with light and receives the reflected light coaxially, or oblique ring condensing illumination, in which an illumination light source is arranged in a ring shape and illuminates a substrate mark from diagonally above, or a combination of these illuminations A method is used.

[0004]

However, in the conventional illuminating device, the coaxial epi-illumination can only provide illumination from an angle perpendicular to the optical axis of the image pickup. If you have
There is a substrate mark that cannot be recognized because the contrast of the recognized image is low. In that case, by adopting the oblique ring condensing illumination, the contrast of the recognition image with respect to the above-mentioned substrate mark is improved, but the contrast of the recognition image of another substrate mark with good contrast by the coaxial incident illumination is improved. Some will go down. In other words, the recognition of the substrate mark portion requires a plurality of illuminations and illumination appropriate for the substrate in order to cause a recognition failure in a uniform illumination device due to the characteristics of each substrate type.
In addition, when a plurality of lighting devices are used, the size of the entire lighting device becomes large, so that a small and inexpensive lighting device is required.

The present invention has been made in view of the above circumstances, and has as its object to provide a small and inexpensive illuminating device which can efficiently illuminate board marks having different characteristics and can position the board marks with high precision. The subject.

[0006]

In each of the embodiments of the present invention, the periphery of one end is formed as a reflection surface, and the periphery of the other end is formed as a diffusion surface, and the light beam incident on the reflection surface is diffused from the other end. A hollow pipe-shaped optical element to be emitted, and a plurality of illumination light sources around the light source, and a reflection surface of the optical element such that light from each illumination light source enters the reflection surface of the optical element and is emitted as diffused light. And a light source unit disposed on the end side, wherein when the illumination light source of the light source unit is turned on, the substrate mark is diffused and illuminated by the diffused light from the illuminated light source. With this configuration, the substrate mark is coaxially illuminated by the diffused light.

According to the present invention, in order to further illuminate the oblique light, a plurality of illumination light sources are provided around the periphery, and another light source unit which is disposed at the end of the diffusion surface of the optical element and illuminates the substrate mark obliquely is provided. When the illumination light source of the light source unit is turned on, the substrate mark is illuminated from obliquely above by the light from the illumination light source. This oblique illumination can also be realized by a coaxial optical element similar to the optical element used for coaxial epi-illumination, and an optical element whose exit surface is a refraction surface.

When a common light source is used for coaxial epi-illumination and oblique illumination, the number of light sources can be reduced.
Therefore, the reflecting surface of the optical element for oblique illumination is a half mirror surface, and the light passing through the half mirror surface is configured to be incident on the reflecting surface of the optical element for coaxial incident illumination.

In order to change the illumination system according to the reflection characteristics of the substrate mark, the illumination light sources of the light source units for coaxial epi-illumination and oblique illumination are turned on simultaneously, or only one of the light sources of one of the light source units is turned on. It is lit. In the embodiment in which the light source is shared, both optical elements are configured to be movable up and down, the optical elements are moved downward according to the illumination mode, and light from the light source is prevented from being incident.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail based on embodiments shown in the drawings.

[First Embodiment] FIG. 1 is a block diagram of a substrate mark illuminating apparatus according to a first embodiment of the present invention. In the figure, the reference numeral 1 denotes an imaging device such as a CCD camera, which captures a substrate mark 5 provided on a printed circuit board 4 on which electronic components are mounted, and other substrate marks. The displacement of the printed circuit board is recognized from these images. The captured image of the board mark 5 can be displayed on a monitor 7 connected to the imaging device 1.

In order to photograph the substrate mark 5, the substrate mark 5 is illuminated by the acrylic prism pipe 2 for vertical incident ring illumination. This prism pipe 2 is shown in FIG.
As shown in (A), the circumference of one end (upper) is 45 °
Is a hollow pipe-shaped optical element formed as a chamfered reflecting surface 2a and around the other end (bottom) as a diffusion transmitting surface 2b, and the diameter of the hollow portion 2c is determined by the substrate mark to be illuminated. Is sized so that almost the entirety enters the interior of the hollow part. The prism pipe 2 has a shape substantially axially symmetric with respect to the center axis 2d, and the center axis 2d coincides with the imaging optical axis of the imaging device 1.

The light source unit 3 is a prism pipe 2
The light source unit 3 includes a plurality of illumination light sources (LEDs) horizontally arranged along a circumference as shown in detail in FIG.
3a is attached to a ring-shaped support plate 3b. As shown in FIG. 4, the light beam from each illumination light source 3a is reflected by the reflecting surface 2a of the prism pipe 2, falls vertically, is substantially diffused by the diffuse transmitting surface 2b, and is emitted downward, and The mark 5 is vertically diffusely illuminated (coaxial epi-illumination).

Further, another light source unit 6 is mounted below the prism pipe 2, and this light source unit 6 has a circular ring-shaped support plate 6b as shown in FIG. 1, a plurality of illumination light sources 6a are attached, and light from each illumination light source 6a is condensed on the substrate mark 5 and illuminates the substrate mark 5 from obliquely above as shown in FIG. illumination).

The image pickup device 1, the prism pipe (optical element) 2, and the light source units 3 and 6 are attached to the illumination device main body so as to be relatively movable with respect to the substrate mark 5. The entire lighting device is attached to an XY moving mechanism (not shown) of the component mounting device.
It is configured to be able to move in the X and Y directions.

In such a configuration, the printed circuit board 4
When photographing the upper substrate mark 5 and recognizing the position, the illuminating device sets the axis center of the prism pipe 2 (the imaging optical axis of the imaging device 1) 2d to substantially coincide with the center of the substrate mark 5.
It moves on the substrate mark 5. When the substrate mark 7 is a mark of high-reflectance and a beautiful metal plating, coaxial epi-illumination using the light source unit 3 is preferable, and when the substrate mark is covered with a cover film, the light source unit 6 is replaced. Since the oblique illumination used is good, one or both light source units are used in consideration of the reflection characteristics of the substrate mark.

For this purpose, first, each illumination light source 3a of the light source unit 3 is turned on, and then each illumination light source 6a of the light source unit 6 is turned on.
Is turned on, the respective illumination light sources 3a of the light source unit 3 are turned off, the board marks 5 are illuminated, the reflected light is photographed by the imaging device 1, and the board mark images are observed on the monitor 7.

When each of the illumination light sources 3a of the light source unit 3 is turned on, a light beam from each of the illumination light sources 3a is vertically reflected internally by the reflection surface 2a of the prism pipe 2, and diffused from the diffusion transmission surface 2b as diffused light. Be injected. Thereby, the substrate mark 5 is diffused and illuminated by the diffused light from each of the illumination light sources 3a. When each illumination light source 6a of the light source unit 6 is turned on, the substrate mark 5 is illuminated from obliquely above by the light from each illumination light source 6a. The user observes the board mark image on the monitor 7 and visually determines whether the contrast of the board mark image is the best in coaxial epi-illumination, oblique illumination, or both of these illuminations. One or both of the illumination light source 3a and the illumination light source 6a are turned on, and the board mark 5 is imaged. The picked-up board mark image is subjected to image processing by an image recognition device (not shown) and its position is recognized.

[Second Embodiment] FIG. 6A shows a lighting device according to a second embodiment of the present invention.
In this embodiment, a prism pipe 20 which is an optical element similar to the prism pipe 2 is used for oblique illumination.
As shown in FIG. 2 (B), the prism pipe 20 has a periphery around one end (upper part) similar to the prism pipe 2.
Although it is formed as a reflecting surface 20a chamfered at an angle, the periphery 20b around the other end (bottom) is a hollow pipe-shaped optical element formed as a refracting surface for refracting a light beam inside. The prism pipe 20 also has an axially symmetrical shape about an axis coinciding with the central axis 2d of the prism pipe 2, and has a structure in which the prism pipe 2 is inserted into a hollow portion of the prism pipe 20. A light source unit 30 is provided above the prism pipe 20 in an area outside the reflection surface 20a. The light source unit 30 includes a plurality of illumination light sources (LEDs) 30a horizontally arranged along the circumference. It is structured to be attached to the ring-shaped support plate 30b.

Light beams from the illumination light sources 3a and 30a are reflected by the reflecting surfaces 2a and 20a of the prism pipes 2 and 20, and fall vertically, as shown in FIG. The light beam from the illumination light source 3a is
b, the light becomes almost diffused light and is emitted downward, and the substrate mark 5
Is vertically diffused (coaxial epi-illumination), while the illumination light source 3
0a is refracted inward by the refraction surface 20b of the prism pipe 20 and condensed on the substrate mark 5;
From above (oblique illumination).

Whether to use coaxial illumination, oblique illumination, or both illuminations is determined in the same manner as in the first embodiment.

Third Embodiment FIG. 7A shows a lighting device according to a third embodiment of the present invention.
This embodiment is different from the second embodiment in that the light source unit 30 of the second embodiment is omitted, and the light source unit 3 is shared by both prism pipes 2 and 20.
The two prism pipes 2 and 20 can be moved in the vertical direction, and one end of the prism pipe 20 is not a reflection surface but a half mirror surface 20a '.

As shown in FIG. 7A, when the reflecting surface 2a and the half mirror surface 20a 'of both prism pipes 2, 20 are at the same height as the illumination light source 3a of the light source unit 3,
The luminous flux from each illumination light source 3a is first
The light that is incident on the half mirror surface 20a 'of the first mirror surface and reflected by the half mirror surface 20a' falls vertically and is refracted by the refraction surface 20b.
The light is refracted inward, converges on the substrate mark 5, and illuminates the substrate mark 5 from obliquely above. At the same time, the light transmitted through the half mirror surface 20a 'is incident on the reflection surface 2a of the prism pipe 2, falls downward, is emitted as diffusion light from the diffusion transmission surface 2b, and illuminates the substrate mark 5 with diffusion. Therefore, the substrate mark is illuminated by the coaxial incident illumination and the oblique illumination.

If it is desired to illuminate the substrate mark only with coaxial incident illumination due to the reflection characteristics of the substrate mark 5, FIG.
As shown in (B), the prism pipe 20 is moved downward so that light from each illumination light source 3a is incident on the reflection surface 2a of the prism pipe 2. As a result, light from each of the illumination light sources 3a is emitted from the diffusion transmission surface 2b of the prism pipe 2 as diffused light, and the substrate mark is illuminated coaxially. On the other hand, when it is desired to perform illumination only with oblique illumination, as shown in FIG. 7C, the prism pipe 2 is moved downward, and the light transmitted through the half mirror surface 20a 'is reflected on the reflection surface 2a of the prism pipe 2. Avoid incidence. Thereby, the light from each illumination light source 3a is refracted inward by the refraction surface 20b of the prism pipe 20, and the substrate mark is illuminated obliquely.

In this embodiment, since the light source unit is common, the configuration is inexpensive.

[Other Embodiments] In each of the embodiments described above, the cross-sectional shape of the prism pipes 2 and 20 is a ring shape. However, the prism pipes 2 and 20 may have other shapes such as a square and a regular polygon. Also, the light source units 3 and 6 may be selected according to the shape.
The arrangement shape of each illumination light source is adapted to the cross-sectional shape of the prism pipe.

Furthermore, in the above-described embodiment, the illumination light source of each light source unit is selectively turned on, and the contrast of the captured image of the board mark is visually determined by the monitor 7 to enable any of the light source units. A light source that performs image processing on the substrate mark image under coaxial epi-illumination, oblique illumination, or both, measures the contrast, and realizes illumination with the best contrast. The illumination light source of the unit may be turned on.

[0028]

As described above, according to the present invention,
The periphery of one end is formed as a reflection surface, and the periphery of the other end is formed as a diffusion surface, and the substrate mark is formed using a hollow pipe-shaped optical element that emits a light beam incident on the reflection surface as diffused light from the other end. Since coaxial epi-illumination is used, the substrate mark can be illuminated with uniform diffused light. In that case, a large number of illumination light sources can be arranged around one end of the optical element, so that the illumination intensity can be increased.

In the present invention, oblique illumination can also be performed. Therefore, according to the reflection characteristics of the substrate mark, both the coaxial epi-illumination and the oblique illumination can be used simultaneously, or any one of the illumination methods can be used. Can be illuminated, and a compact and efficient lighting device can be obtained.

[Brief description of the drawings]

FIG. 1 is a configuration diagram illustrating an overall schematic configuration of a lighting device according to a first embodiment of the present invention.

FIG. 2A is a perspective view showing an embodiment of a prism pipe, and FIG. 2B is a perspective view of a prism pipe of another embodiment.

FIG. 3 is a top view of a prism pipe and a light source unit according to the first embodiment.

FIG. 4 is an explanatory diagram showing a state in which light from an illumination light source is diffused and emitted by a prism pipe in the first embodiment.

FIG. 5 is a top view illustrating an arrangement of an illumination light source that performs oblique illumination in the first embodiment.

FIG. 6A is a configuration diagram showing the overall schematic configuration of a lighting device according to a second embodiment of the present invention, and FIG. 6B is a diagram showing light from an illumination light source diffused or refracted by a prism pipe and emitted. FIG. 4 is an explanatory diagram showing a state in which

FIG. 7A is a configuration diagram illustrating an overall schematic configuration of an illumination device according to a third embodiment of the present invention, and FIG. 7B is a state in which light from an illumination light source is diffused and emitted by a prism pipe. (C) is an explanatory diagram showing a state in which light from an illumination light source is refracted by a prism pipe and emitted.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Image pickup device 2 Prism pipe 3 Light source unit 4 Printed circuit board 5 Board mark 6 Light source unit 7 Monitor

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2F065 AA03 AA16 AA20 BB27 CC01 CC25 DD02 GG17 HH02 HH12 HH13 HH14 JJ03 JJ09 JJ26 LL01 LL46 SS02 SS13 TT02 2G051 AA65 AB20 BA01 BB01 BB03 BB20 A043

Claims (5)

[Claims] 1. An illuminating device for illuminating a substrate mark on a substrate, wherein a periphery of one end is formed as a reflection surface and a periphery of the other end is formed as a diffusion surface, and a light beam incident on the reflection surface is reflected from the other end. A hollow pipe-shaped optical element that emits as diffused light, and an optical element that includes a plurality of illumination light sources around the light source so that light from each of the illumination light sources enters the reflection surface of the optical element and is emitted as diffused light. And a light source unit disposed on the reflection surface end side of the light source unit, wherein when the illumination light source of the light source unit is turned on, the substrate mark is diffused and illuminated by the diffused light from the illuminated light source. Lighting equipment. 2. An illumination device for illuminating a substrate mark on a substrate, wherein a periphery of one end is formed as a reflection surface, and a periphery of the other end is formed as a diffusion surface, and a light beam incident on the reflection surface is reflected from the other end. A hollow pipe-shaped optical element that emits as diffused light, and an optical element that includes a plurality of illumination light sources around the light source so that light from each of the illumination light sources enters the reflection surface of the optical element and is emitted as diffused light. A first light source unit disposed on an end side of a reflective surface of the optical element, and a second light source provided with a plurality of illumination light sources around the end and disposed on an end side of a diffusion surface of the optical element to illuminate a substrate mark from an oblique direction When the illumination light source of the first light source unit is turned on, diffuse illumination is performed by diffused light from the illumination light source of the first light source unit whose substrate mark is turned on, and When the light source is turned on, Lighting device characterized in that the mark is illuminated obliquely from above by the light from the illumination light source of the second light source unit is turned on. 3. A lighting device for illuminating a substrate mark on a substrate, wherein a periphery of one end is formed as a reflection surface, and a periphery of the other end is formed as a diffusion surface, and a light beam incident on the reflection surface is reflected from the other end. A hollow pipe-shaped first optical element that emits as diffused light, a reflection surface formed around one end and a refraction surface formed around the other end, and a light beam incident on the reflection surface is directed inward from the other end. A hollow pipe-shaped second optical element that refracts and emits light, and a plurality of illumination light sources around the light source. Light from each illumination light source is incident on the reflection surface of the first optical element and emitted as diffused light. A first light source unit disposed on the reflection surface end side of the first optical element, and a plurality of illumination light sources around the first optical element, and light from each illumination light source is reflected by the second optical element. The reflecting surface of the second optical element so that it is incident on the surface and is emitted as refracted light And a second light source unit disposed on the side of the first light source unit. When the illumination light source of the first light source unit is turned on, the diffused light from the illumination light source of the first light source unit with the board mark turned on is provided. The illumination device is characterized in that when the illumination light source of the second light source unit is illuminated by diffuse illumination, the substrate mark is illuminated obliquely from above by the light from the illumination light source of the second light source unit with the substrate mark illuminated. . 4. An illuminating device for illuminating a substrate mark on a substrate, wherein a periphery of one end is formed as a reflection surface, and a periphery of the other end is formed as a diffusion surface, and a light beam incident on the reflection surface is reflected from the other end. A hollow pipe-shaped first optical element that emits as diffused light, a half mirror surface around one end and a refractive surface around the other end, and a first optical element outside the first optical element. It is arranged so that it is substantially concentric with the optical element and the half mirror surface is substantially at the same height as the reflection surface of the first optical element, and refracts the light beam reflected by the half mirror surface inward from the other end. A hollow pipe-shaped second optical element for emitting light and transmitting the light transmitted through the half mirror surface to the reflecting surface of the first optical element, and a plurality of illumination light sources around the light source. Enters the half mirror surface of the first optical element The light reflected from the half mirror surface is emitted as refracted light, and the light transmitted through the half mirror surface is incident on the reflection surface of the first optical element and emitted as diffused light. When the illumination light source of the light source unit is turned on, the substrate mark is diffused and illuminated with the diffused light by the first optical element from the illuminated light source and the refraction by the second optical element. A lighting device characterized by being illuminated obliquely from above with light. 5. The illumination light source of the light source unit when each of the first and second optical elements is configured to be vertically movable with respect to the light source unit, and when the second optical element is moved downward. Is incident only on the reflection surface of the first optical element, and the substrate mark is diffused and illuminated with the diffused light from the illuminated illumination light source by the first optical element, and the first optical element moves downward. In this case, the light transmitted through the half mirror surface is not incident on the first optical element, and the substrate mark is illuminated obliquely from above by the refracted light from the illuminated illumination light source by the second optical element. The lighting device according to claim 4, wherein: