JPH10160414A - Illuminator and picture inspection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an illuminator, which do not cause uneven illuminance even when lamps are provided successively and can emit light rays along the same line. SOLUTION: Fluorescent lamps 13 are arranged in parallel with each other in a housing section 12a provided on the back side of a main body section 12 and an optical path for passing the light rays emitted from the lamps 13 is provided. At both ends of a light transmission body 12b, first and second step sections 15 and 17 are provided as engaging sections. The curved surfaces from the lower surfaces 16a of the first step sections 15 and curved surfaces from the second step sections 17 form a continuous curved surface (light reflecting surface) 18.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lighting device using a long light-emitting body such as a fluorescent lamp and an image inspection device using the lighting device.

[0002]

2. Description of the Related Art In a wide variety of fields, an image defect inspection apparatus which detects a defect such as a stain on an object by a camera and detects the image by embedding the obtained image has been widely used.

Meanwhile, an image defect inspection apparatus for detecting a defect of a wide and long paper or a steel plate having a width exceeding 5 m is generally constructed by combining a plurality of cameras and lighting devices.

FIG. 12 shows an example of such an image defect inspection apparatus. The wide inspection object 103 shown in the figure is moved in the direction of the arrow 103b by the transfer device 103a shown by the dotted line. The image defect inspection apparatus is configured by installing a plurality of cameras 101 near an inspection area 100 of an inspection target 103 and arranging a plurality of lighting devices 102 at positions facing the cameras 101. Then, as the object 103 passes through the inspection area 100, a defect is detected for the object 103.

[0005] That is, when the width of the inspection object is small, it is possible to illuminate the inspection area with a single illumination device for one or a plurality of cameras. In the case of an object, it is difficult to illuminate the inspection area with a single illuminating device. Therefore, as shown in FIG. 12, a plurality of illuminating devices 102 are used in series.

FIG. 13 shows an example of the configuration of such a lighting device 102. As shown in FIG.
Is configured by housing a fluorescent lamp 105 in a container 104. At both ends of each fluorescent lamp 105, electrode portions 106a, 10a
6b is provided. FIG. 1 shows the individual illuminance characteristics of each lighting device 102 in which the horizontal axis represents the width of the fluorescent lamp and the vertical axis represents the illuminance.
As shown in FIG. 4, the illuminance characteristic graph A shows both ends A of the fluorescent lamp.
The illuminance decreases at a and Ab, and an appropriate illuminance can be obtained at the center. That is, the characteristics shown in FIG. 14 are obtained due to the influence of the electrode portions 106 a and 106 b (non-light emitting portions) of the fluorescent lamp 105 and the end of the container 104. Accordingly, when a plurality of lighting devices 102 having such characteristics are connected as shown in FIG. 12, the lighting devices 102 are connected so that the side surfaces of the containers 104 are brought into contact as shown in FIG.

FIG. 15 shows such a conventional lighting device 102.
Shows the total illuminance when three are connected. 13, the vertical axis represents the illuminance as in FIG. 14, and the horizontal axis represents the illuminance in FIG.
The three fluorescent devices are arranged side by side to form a continuous fluorescent lamp width. FIG. 12 shows a configuration in which a large number of lighting devices 102 are connected, but FIG. 15 simply shows the total illuminance characteristics when three are connected. As a result, in the illuminance characteristic graph Β, the illuminance is significantly reduced at both ends Βa and Βb of the connected illuminating device group as in FIG. The illuminance between the lighting devices Δc and Δd does not decrease as much as both ends due to the presence of the adjacent fluorescent lamps, but decreases from the center due to the presence of the electrode portions of the fluorescent lamps. In the case of using the image processing device, the collection and processing of precise image processing data has been hindered.

Therefore, for example, as shown in FIG. 16, it is conceivable to arrange a plurality of lighting devices 102 in a staggered manner. That is, the lighting device 1 has the overlapping portion 107 at the end of the adjacent lighting device 102.
Insufficient illuminance at the end of 02 is compensated by the illumination of the adjacent illumination device 102.

However, when the plurality of lighting devices 102 are arranged in a staggered manner as described above, the irradiation position (in FIG. 16) differs between the adjacent lighting devices 102,
That is, there is a problem that a difference D occurs between the inspection positions corresponding to the adjacent lighting devices and the inspection accuracy is deteriorated. In this case, it can be dealt with by performing software correction in a later image processing step, but there is a problem that the configuration becomes complicated or the processing speed is hindered.

In addition, in such an arrangement, there is also a problem that the space is widened only by the difference D, and the entire image inspection apparatus becomes large.

[0011]

As described above, in an image inspection apparatus for inspecting a wide object by image processing, it is necessary to arrange a plurality of lighting devices in series. Then, illuminance unevenness occurs. For this reason, it is conceivable to arrange a plurality of lighting devices in a staggered manner,
There is a problem that a difference occurs in the irradiation position of the adjacent lighting device, that is, a difference occurs in the inspection position, which leads to a deterioration in inspection accuracy and an increase in size of the device.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and uses an illuminating device capable of irradiating the same line without generating uneven illuminance even when the illuminating device is connected, and using the illuminating device. It is an object to provide an image inspection device.

It is a further object of the present invention to provide a lighting device that can be made smaller and an image inspection device using the lighting device.

Another object of the present invention is to provide a lighting device capable of improving illuminance.

[0015]

According to the first aspect of the present invention, to solve such a problem, a long luminous body, the luminous body, and the light emitted from the luminous body are emitted. A main body provided with an optical path to pass therethrough, and an engaging portion that engages with an end of the device having the same configuration and is integrated in the axial direction of the luminous body at at least one end in the axial direction of the luminous body. And a light reflecting surface disposed opposite to the light emitter with the light path interposed therebetween and reflecting light emitted from the light emitter in a predetermined direction. Is done.

According to the present invention, a plurality of lighting devices can be engaged so that their respective engaging portions face each other, and these lighting devices can be connected. At this time, for example, the illuminance is reduced because the electrode portion of the luminous body, for example, the fluorescent lamp is located at the engaging portion of one lighting device, but the engaging portion of the other adjacent lighting device corresponding to this position is reduced. The light reflected and radiated on the light reflecting surface can compensate for this shortfall.

Further, since the device according to the present invention can be engaged with the device end portion having the same configuration and integrated in the axial direction of the luminous body, the size can be further reduced.

In this case, the light-reflecting surface is curved as in claim 2, a light-reflecting surface is flat as in claim 3, or a plurality of planar light-reflecting surfaces with different inclination angles as in claim 4. It can be a reflective surface. By configuring the light reflecting surface as in claim 2, the irradiation range can be expanded,
By configuring the light reflecting surface as described in claim 3 or 4, it is possible to improve illuminance.

Further, the engaging portion may be configured to have two step portions having different heights in a stepwise manner, or may be configured to have one step portion.

Further, the main body may be formed of a light transmitting synthetic resin.

[0021] In this lighting device, the respective engaging portions may be engaged so as to face each other, and the lighting devices may be connected.

According to a ninth aspect of the present invention, the illuminating device is applied to an image inspection apparatus, that is, a transport unit for moving an inspection object and a plurality of imaging units for capturing an image of a predetermined area of the inspection object. A lighting device for irradiating the predetermined area with light, the lighting device having a long light-emitting body, an optical path for accommodating the light-emitting body and passing light emitted from the light-emitting body; Provided, and a main body portion provided with an engaging portion integrated with the device end portion having the same configuration and integrated in the axial direction of the light emitting body at at least one end portion in the axial direction of the light emitting body, A light reflecting surface disposed at the other end of the main body portion, facing the light emitting body with the light path interposed therebetween, and reflecting a light emitted from the light emitting body in a predetermined direction; A plurality of these engaging parts so as to face each other Engaged thereby, allowed connecting these illumination devices, wherein the in a predetermined area of the inspection object is a structure in which as arranged for emitting light.

[0023]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a perspective view of a lighting device according to an embodiment of the present invention, FIG. 2 is a perspective view schematically showing a part of the lighting device shown in FIG. 1, and FIG. FIG. 4 is a front view, FIG. 5 is a partially transparent plan view, and the same parts are indicated by the same numbers.

In the lighting device 11 according to one embodiment of the present invention, the storage unit 12a provided on the back side of the
The fluorescent lamps 13 are arranged side by side. Electrodes 14 are provided at both ends of each fluorescent lamp 13. Although shown only in FIG. 4 from the electrode part 14, the lead wire 19 is drawn out.

An optical path through which light emitted from the fluorescent lamp 13 passes, for example, a light guide 12b made of acrylic resin, which is a light-transmitting resin, is provided on the front side of the housing portion 12a. At both ends of the light guide 12b, a first step portion 15 and a second step portion 17 are provided as engagement portions. That is, at a position separated from the fluorescent lamp 13 by a predetermined distance, the first
A step 15 is provided. The width of the first step portion 15 may be at least a width that shields the electrode portion 14 of the fluorescent lamp 13. Therefore, the first step portions 15 are provided on both sides of the light guide 12b with the same width.

The light guide 12b extends further from the first step portion 15 to the front side, and the lower surface 16a in the figure is
6b. From the upper surface 16b, the second step 17
Is provided. A curved surface extends from the lower surface 16a to the second step portion 17. Further, the light guide 12b is provided with the second step portion 1.
7 is also curved from the lower end. In FIG. 1, these curved surfaces are hatched.

That is, the curved surface from the lower surface 16a of the first step portion 15 and the curved surface from the second step portion 17 are continuous curved surfaces 18
(Light reflecting surface), and only the curved surface 18 is taken out and shown in a shape as shown in FIG. FIG. 2 shows this curved surface in a perspective view from the back side in FIG.

The curved surface 18 is a light reflecting surface, and the light emitted from the fluorescent lamp 13 is reflected by the light reflecting surface 18 and irradiated upward as shown by an arrow 19 in FIG. The curved surface of the light reflecting surface 18 is a part of an ellipse. By making the light reflecting surface 18 curved as described above, light emitted from the three fluorescent lamps 13 is reflected by the light reflecting surface 18 and irradiated so as to be focused at a predetermined position above the light guide 12b. You.

The light reflecting surface 18 can be formed by attaching a metal film having excellent light reflecting characteristics or by depositing it by vapor deposition.

FIG. 6 shows a configuration in which two illuminating devices 11 according to the present invention having the above configuration are connected in series. The two first and second lighting devices 11a and 11b engage the respective engaging portions so as to face each other, that is,
The lighting devices are connected so that the stepped portions of the lighting devices are engaged with each other in a rotated state. More specifically, the first step 15a of the first lighting device 11a is engaged with the second step 17b of the second lighting device 11b, and the second step 17a of the first lighting device 11a is 1st step part 1 of device 11b
5b.

With such engagement, the light reflecting surface 18a of the first lighting device 11a and the light reflecting surface 18b of the second lighting device 11b are rotated by 180 ° with respect to each other, but the axis of the fluorescent lamp is rotated. Can be integrated in the direction, that is, continuous in the lateral direction.

The fluorescent lamp 13a of the first lighting device 11a
And the fluorescent lamp 13b of the second lighting device 11b are arranged outside each other, and are arranged at positions where light emission from the light reflecting surfaces 18a and 18b is not hindered.

FIG. 7 is a diagram showing the total illuminance characteristics when three illuminating devices according to the present invention shown in FIGS. 1 to 5 are connected by the connecting method shown in FIG. In the figure, the solid line C shows the characteristics of the device according to the present invention, and the dotted line D shows the characteristics when the conventional lighting device shown in FIG. 15 is connected for reference.

According to the characteristics of the device according to the present invention, both ends C
Although a decrease in the illuminance is observed in a and Cb as in the conventional case, the illuminance characteristics Cc and C at the place where three lighting devices are connected are shown.
Although d is slightly reduced as compared with each central part,
Compared with the conventional reduction in illuminance indicated by the dotted line D, a remarkable improvement is recognized, and the optical characteristics required for the image inspection apparatus can be satisfied.

That is, in the present invention, as shown in FIG. 6, the fluorescent lamp 1 is provided at the first step portion 15a of the first lighting device 11a.
Since the electrode portion 3a is located, the illuminance decreases,
The second step portion 1 of the second lighting device 11b corresponding to this position
The light reflected and irradiated on the light reflecting surface 18 below 7b compensates for this shortfall. Similarly, the second lighting device 11b
Of the illuminance at the first step portion 15b of the first lighting device 1
The light 1a is corrected by the light reflected and irradiated on the light reflecting surface 18 below the second step 17a.

The present invention is not limited to the above-described embodiment, and various modifications can be made within the scope of the technical idea.

For example, in the above embodiment, the light guide 1
Although an example is shown in which 2b is formed of a light-transmitting acrylic resin, it may be formed in a box shape having a hollow portion instead of a synthetic resin.

FIG. 8 schematically shows a cross section of the lighting device according to the above-described embodiment.
The focused light is irradiated in the direction of the arrow by the opposing curved reflecting surface 18. However, the light reflecting surface is not limited to this, and may be a planar light reflecting surface 18a as shown in FIG. By using the flat reflecting surface 18a, it is possible to make the irradiation light parallel light. Further, as another configuration for converging light in a certain range, as shown in FIG. 10, it is also possible to use a composite reflecting surface in which a plurality of planar reflecting surfaces 18b, 18c, and 18d having different inclination angles are continuous. is there.

Further, the lighting device according to the present invention shown in FIGS. 1 to 6 has a configuration in which a plurality of steps 15 and 17 are provided. As shown in FIG. 11, a single step 15a is formed. However, it may also engage with a single step of another device to be connected.

Further, the lighting device according to the present invention is shown in FIG.
Although it is effective as an image inspection device as described in (1), it can also be effectively used as a backlight of an LCD (Liquid Crystal Display).

[0042]

As described in detail above, according to the present invention,
A long light-emitting body and, while accommodating the light-emitting body, an optical path for passing light emitted from the light-emitting body toward a predetermined radial direction of the light-emitting body is provided, and an apparatus end having the same configuration. An engaging portion that engages and is integrated in the axial direction of the luminous body is provided on at least one end in the axial direction of the luminous body, and faces the luminous body across the optical path. Since it is arranged and provided with a light reflecting surface that reflects light emitted from the light emitting body in a predetermined direction, even when connected and arranged, illuminance unevenness does not occur, and irradiation can be performed on the same line, Further, the size can be further reduced. Further, the illuminance can be improved by making the light reflecting surface a curved surface or a plurality of planar reflecting surfaces having different inclination angles.

[Brief description of the drawings]

FIG. 1 is a perspective view of a lighting device according to an embodiment of the present invention.

FIG. 2 is a perspective view schematically showing a part of the lighting device shown in FIG.

FIG. 3 is a side view of the lighting device shown in FIG. 1;

FIG. 4 is a front view of the lighting device shown in FIG. 1;

FIG. 5 is a partially transparent plan view of the lighting device shown in FIG. 1;

FIG. 6 is a view showing a method of connecting the lighting devices according to the present invention.

FIG. 7 is a diagram showing an overall illuminance characteristic when three illuminating devices according to the present invention are connected by the connecting method shown in FIG. 5;

FIG. 8 is a diagram showing an example of a light reflecting surface of the lighting device according to the present invention.

FIG. 9 is a view showing another example of the light reflecting surface of the lighting device according to the present invention.

FIG. 10 is a view showing still another example of the light reflecting surface of the lighting device according to the present invention.

FIG. 11 is a diagram showing another embodiment of the lighting device according to the present invention.

FIG. 12 is a diagram illustrating an example of a conventional image defect inspection apparatus.

FIG. 13 is a diagram for explaining a conventional method of connecting a plurality of lighting devices.

FIG. 14 is a diagram showing the illuminance characteristics of the lighting device alone.

FIG. 15 is a diagram showing illuminance characteristics when a lighting device is connected by a conventional method.

FIG. 16 is a diagram for explaining another conventional method for connecting a plurality of lighting devices.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Illumination device 12 Main part 12a Storage part 12b Light guide 13 Fluorescent lamp 14 Electrode part 15 1st step part 17 2nd step part 18 Light reflection surface

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Tadashi Itagaki 66-2 Horikawa-cho, Saiwai-ku, Kawasaki City, Kanagawa Prefecture

Claims (9)

[Claims] An elongated light emitting body, an optical path for receiving the light emitted from the light emitting body and being provided at one end thereof, and being engaged with an apparatus end having the same configuration. An engaging portion that is integrated in the axial direction of the light-emitting body, a main body portion provided at at least one end in the axial direction of the light-emitting body, and the other end of the main body portion, with the optical path interposed therebetween; A lighting device, comprising: a light-reflecting surface that is arranged to face a light-emitting body and reflects light emitted from the light-emitting body in a predetermined direction. 2. The lighting device according to claim 1, wherein the light reflecting surface is curved. 3. The lighting device according to claim 1, wherein the light reflecting surface is planar. 4. The lighting device according to claim 1, wherein the light reflecting surface is a plurality of planar reflecting surfaces having different inclination angles. 5. The lighting device according to claim 1, wherein the engaging portion has two step portions having different heights in a stepwise manner. 6. The lighting device according to claim 1, wherein the engaging portion has one step. 7. The lighting device according to claim 1, wherein the main body is formed of a light-transmitting synthetic resin. 8. An illuminating device comprising: a plurality of engaging portions of the illuminating device according to claim 1 being engaged with each other so as to face each other; and connecting the illuminating devices. 9. A lighting device, comprising: a transport unit for moving an inspection object; a plurality of cameras for capturing an image of a predetermined area of the inspection object; and an illumination device for irradiating the predetermined area with light. Is provided with an elongated luminous body, an optical path for accommodating the luminous body, and for transmitting light emitted from the luminous body, and engaging with an apparatus end portion having the same configuration as the axis of the luminous body. A main body provided at at least one end of the luminous body in the axial direction, and the other end of the main body facing the luminous body with the optical path interposed therebetween. A plurality of lighting devices, each of which has a light reflecting surface for reflecting light emitted from the light emitter in a predetermined direction, and engaging these engaging portions so as to face each other. And irradiate light to a predetermined area of the inspection object. Image inspection apparatus which is a structure in which as arranged.