JP2021148633A - Illumination device, illumination device control method, exterior appearance inspection device, and program - Google Patents

Abstract

To provide an illumination device, illumination device control method, exterior appearance inspection device, and program that can avoid detection accuracy of a defect on a surface of an inspection object from falling.SOLUTION: An illumination device 101 comprises: a first light source 31; second and third light sources 32 and 33 that are provided in the vicinity of the first light source 31; and a light source control unit 13. The first light source 31 is configured to irradiate a workpiece W1 to be subjected to an exterior inspection with a first illumination light ray L41 via a half mirror 2 or a prism 6. The first illumination light ray L41 is coaxial epi-illumination that has an irradiation optical axis serving as the same axis as an optical axis Z1 of an image formation optical system 1 image-forming an image of the workpiece W1 to be subjected to the exterior inspection. The second and third light sources 32 and 33 are configured to irradiate the workpiece W1 to be subjected to the exterior inspection with second and third irradiation light rays L42 and L43 respectively via the half mirror 2 or the prism 6. Illumination optical axes of the second and third illumination light rays L42 and L43 intersect an illumination incidence optical axis of the first illumination light ray L41.SELECTED DRAWING: Figure 1

Description

The present invention relates to a lighting device, a control method for the lighting device, a visual inspection device, and a program.

In the inspection device disclosed in Patent Document 1, each image pickup target area defined for the work to be inspected is irradiated with diffused light having a size capable of illuminating the entire inspection target area in the area, and specular reflection from the work. Align the camera and light source so that the light can be imaged. Each time this alignment is performed, the lighting range of the light source is limited to only a part of the emission surface, and spot illumination that illuminates a part of the inspection target area and the entire inspection target area without limiting the lighting range. The whole lighting is executed in order, and the camera is made to perform imaging for each illumination. As a result, both unevenness defects and poor smoothness on the surface of the molded product can be detected efficiently and accurately using the same optical system.

Japanese Unexamined Patent Publication No. 2008-215875

However, with such an inspection device, the accuracy of detecting defects on the surface to be inspected may be lowered.

An object of the present disclosure is to provide a lighting device, a control method of the lighting device, a visual inspection device, and a program capable of avoiding a decrease in detection accuracy of a surface defect to be inspected in view of the above-mentioned problems. It is in.

The lighting device according to one of the embodiments of the present disclosure is
The first light source and
The second and third light sources provided in the vicinity of the first light source, and
Equipped with a light source control unit
The first light source irradiates the appearance inspection object with the first illumination light through a half mirror or a prism.
The first illumination light is coaxial epi-illumination having an irradiation optical axis that is the same axis as the optical axis of the imaging optical system that forms an image of the appearance inspection object.
The second and third light sources irradiate the appearance inspection object with the second and third illumination lights via the half mirror or the prism, respectively.
The irradiation optical axes of the second and third illumination lights intersect with the illumination emission axes of the first illumination light, respectively.
The light source control unit exclusively lights the first, second, and third light sources.

The visual inspection apparatus according to one of the embodiments of the present disclosure is
Lighting equipment and
Equipped with an imaging unit
The lighting device is
A first light source, second and third light sources provided in the vicinity of the first light source, and a light source control unit are provided.
The first light source irradiates the appearance inspection object with the first illumination light through a half mirror or a prism.
The first illumination light is coaxial epi-illumination having an incident optical axis that is the same axis as the optical axis of the imaging optical system that forms an image of the appearance inspection object.
The second and third light sources irradiate the appearance inspection object with the second and third illumination lights via the half mirror or the prism, respectively.
The incident optical axes of the second and third illumination lights intersect with the incident optical axes of the first illumination light, respectively.
The light source control unit exclusively lights the first light source and the second and third light sources.
When the light source control unit exclusively lights the first light source and the second and third light sources, the image pickup unit captures the appearance inspection object and lights only the first light source. The image captured when only the second light source is turned on, the image captured when only the second light source is turned on, and the image captured when only the third light source is turned on are generated.

The method for controlling the lighting device according to one of the embodiments of the present disclosure is as follows.
The first light source and
A second and third light sources provided in the vicinity of the first light source are provided.
The first light source irradiates the appearance inspection object with the first illumination light through a half mirror or a prism.
The first illumination light is coaxial epi-illumination having an irradiation optical axis that is the same axis as the optical axis of the imaging optical system that forms an image of the appearance inspection object.
The second and third light sources irradiate the appearance inspection object with the second and third illumination lights via the half mirror or the prism, respectively.
In the method of controlling the illumination device, the irradiation optical axes of the second and third illumination lights intersect with the illumination emission axes of the first illumination light, respectively.
The step includes exclusively turning on the first, second and third light sources.

The program according to one of the embodiments of the present disclosure is
The first light source and
A second and third light sources provided in the vicinity of the first light source are provided.
The first light source irradiates the appearance inspection object with the first illumination light through a half mirror or a prism.
The first illumination light is coaxial epi-illumination having an irradiation optical axis that is the same axis as the optical axis of the imaging optical system that forms an image of the appearance inspection object.
The second and third light sources irradiate the appearance inspection object with the second and third illumination lights via the half mirror or the prism, respectively.
The irradiation optical axes of the second and third illumination lights are used in a computer that operates as an illumination device that intersects the illumination emission axes of the first illumination light.
The step of exclusively turning on the first, second, and third light sources is executed.

According to the present disclosure, it is possible to provide a lighting device, a control method of the lighting device, a visual inspection device, and a program capable of avoiding a decrease in detection accuracy of a surface defect to be inspected.

It is a schematic diagram which shows the lighting apparatus which concerns on Embodiment 1. FIG. It is a side view which shows the main part of the lighting apparatus which concerns on Embodiment 1. FIG. It is a front view which shows the main part of the lighting apparatus which concerns on Embodiment 1. FIG. It is a schematic diagram which shows one operation example of the lighting apparatus which concerns on Embodiment 1. FIG. It is a schematic diagram which shows an example of the appearance inspection apparatus provided with the lighting apparatus which concerns on Embodiment 1. FIG. It is a bottom view which shows the main part of an example of the appearance inspection apparatus provided with the lighting apparatus which concerns on Embodiment 1. FIG. It is a control block diagram of an example of the appearance inspection apparatus which concerns on Embodiment 1. FIG. It is a flowchart which shows the control method of the visual inspection apparatus which concerns on Embodiment 1. FIG. It is a flowchart which shows the control method of the visual inspection apparatus which concerns on Embodiment 1. FIG. FIG. 5 is a timing chart showing the operation of each configuration of an example of the visual inspection apparatus according to the first embodiment. It is a schematic diagram which shows the modification 1 of the lighting apparatus which concerns on Embodiment 1. FIG. It is a side view which shows the modification 2 of the main part of the lighting apparatus which concerns on Embodiment 1. FIG. It is a schematic diagram which shows the modification 3 of the lighting apparatus which concerns on Embodiment 1. FIG. It is a side view which shows the main part of the modification 3 of the lighting apparatus which concerns on Embodiment 1. FIG. It is a front view which shows the main part of the modification 3 of the lighting apparatus which concerns on Embodiment 1. FIG. It is a side view which shows the main part of the modification 3 of the lighting apparatus which concerns on Embodiment 1. FIG. It is a top view which shows the main part of the modification 3 of the lighting apparatus which concerns on Embodiment 1. FIG. It is a schematic diagram which shows the modification 4 of the lighting apparatus which concerns on Embodiment 1. FIG. It is a schematic diagram which shows the modification 5 of the appearance inspection apparatus which concerns on Embodiment 1. FIG. It is a bottom view which shows the main part of the modification 5 of the visual inspection apparatus which concerns on Embodiment 1. FIG. It is a figure which shows one configuration example of the hardware included in the visual inspection apparatus.

Hereinafter, specific embodiments to which the present invention is applied will be described in detail with reference to the drawings. However, the present invention is not limited to the following embodiments. Further, in order to clarify the explanation, the following description and drawings have been simplified as appropriate.

(Embodiment 1)
The first embodiment will be described with reference to FIGS. 1 to 3. FIG. 1 is a schematic view showing a lighting device according to the first embodiment. FIG. 2 is a side view showing a main part of the lighting device shown in FIG. FIG. 3 is a front view showing a main part shown in FIG.

As a matter of course, the right-handed XYZ coordinates shown in FIG. 1 and other drawings are for convenience to explain the positional relationship of the components. Usually, the Z-axis plus direction is vertically upward, and the XY plane is a horizontal plane, which is common between drawings.

As shown in FIG. 1, the lighting device 101 includes a half mirror 2 and a light source group 3. The lighting device 101 and the imaging device 1 constitute a visual inspection device. The visual inspection device is, for example, a line scanner, a line scan camera, an area scanner, or an area scan camera.

The image pickup device 1 is provided above the appearance inspection object W1 (also referred to as a work) (here, the plus side in the Z-axis direction). The image pickup device 1 may be any device that captures an image pickup target and generates image data. The image pickup device 1 is, for example, a CCD (Charge Coupled Device) sensor or a CMOS (Complementary Metal Oxide Semiconductor) sensor. The image pickup device 1 may be a two-dimensional sensor (area sensor) that images an area (area) having a predetermined area in the appearance inspection object W1. The image pickup device 1 may generate a line-shaped image by imaging a line-shaped region in the appearance inspection object W1. The image pickup device 1 may include, for example, a row of light receiving elements. The light receiving element row includes a plurality of light receiving elements arranged in one direction. Instead of the image pickup device 1, an imaging optical system that forms an image of the appearance inspection object W1 may be arranged.

The appearance inspection object W1 is transported in the transport direction X1 (here, the plus side in the X-axis direction) by a transport device (not shown) or the like. The transport device is an external device of the above-mentioned visual inspection device. The transfer device is, for example, a roller conveyor or a belt conveyor. The optical axis Z1 of the image pickup device 1 intersects the main portion of the surface W1a of the appearance inspection object W1 substantially perpendicularly.

The half mirror 2 is provided between the image pickup device 1 and the appearance inspection object W1. The light source group 3 is provided on the side of the half mirror 2 (here, the minus side in the X-axis direction).

The light source group 3 includes a first light source 31, a second light source 32, and a third light source 33. As the first light source 31, the second light source 32, and the third light source 33, for example, a bullet-shaped LED (light emitting diode) may be used. The second light source 32 and the third light source 33 are provided in the vicinity of the first light source 31. The first light source 31, the second light source 32, and the third light source 33 may be adjacent to each other or may be arranged at a predetermined interval. Further, the second light source 32 and the third light source 33 may sandwich the first light source 31.

The first light source 31 irradiates the appearance inspection object W1 with the first illumination light L41 via the half mirror 2. Specifically, as shown in FIGS. 1 and 2, the first light source 31 emits the first illumination light L41 along the emission light axis L41a. The emission optical axis L41a extends in the transport direction X1. At least a part of the first illumination light L41 is reflected by the half mirror 2 and irradiates the appearance inspection object W1. Then, the reflected light from the appearance inspection object W1 passes through the half mirror 2 and reaches the image pickup surface of the image pickup device 1, and the appearance inspection object W1 forms an image on this image pickup surface. The optical axis Z1 of the image pickup device 1 and the irradiation optical axis L41b of the first illumination light L41 are the same axis. Therefore, the first illumination light L41 is a coaxial epi-illumination having an irradiation light axis L41b which is the same axis as the optical axis Z1 of the imaging device 1.

The second light source 32 irradiates the appearance inspection object W1 with the second illumination light L42 via the half mirror 2. Specifically, the second light source 32 emits the second illumination light L42 along the emission optical axis L42a. The outgoing light axis L42a is inclined and extends toward the outgoing light axis L41a. At least a part of the second illumination light L42 is reflected by the half mirror 2 and irradiates the appearance inspection object W1. The irradiation optical axis L42b of the second illumination light L42 intersects with the irradiation optical axis L41b of the first illumination light L41. The place where the irradiation optical axis L42b and the irradiation optical axis L41b intersect may be the irradiation portion W1b of the surface W1a of the appearance inspection object W1. The illumination angle β12 formed by the intersection of the irradiation optical axis L42b and the irradiation optical axis L41b may be in the range of more than 0 (zero) degrees and 5 degrees or less. The upper limit of the illumination angle β12 is preferably 0.5, 1.0, 1.5, 2.0, 2.5 degrees, and the upper limit of the illumination angle β12 is 2.0 degrees. It is preferable, and more preferably 1.0 degree. The angle α32 formed by the intersection of the emission light axis L42a and the emission light axis L41a may be determined so that the illumination angle β12 is within the above range.

The third light source 33 irradiates the appearance inspection object W1 with the third illumination light L43 via the half mirror 2. Specifically, the third light source 33 emits the third illumination light L43 along the emission optical axis L43a. The emission optical axis L43a is inclined and extends toward the emission optical axis L41a. At least a part of the third illumination light L43 is reflected by the half mirror 2 and irradiates the appearance inspection object W1. The irradiation optical axis L43b of the third illumination light L43 intersects with the irradiation optical axis L41b of the first illumination light L41. The place where the irradiation optical axis L43b and the irradiation optical axis L41b intersect may be the irradiation portion W1b of the surface W1a of the appearance inspection object W1. The illumination angle β13 formed by the intersection of the irradiation optical axis L43b and the irradiation optical axis L41b may be in the range of more than 0 (zero) degrees and 5 degrees or less. The upper limit of the illumination angle β13 is preferably 0.5, 1.0, 1.5, 2.0, or 2.5 degrees, and the upper limit of the illumination angle β13 is 2.0 degrees. It is preferable, and more preferably 1.0 degree. The angle α33 formed by the intersection of the emission light axis L43a and the emission light axis L41a may be determined so that the illumination angle β13 is within the above range.

The irradiation optical axis L41b may be located between the irradiation optical axis L42b and the irradiation optical axis L43b. The irradiation optical axis L41b, the irradiation optical axis L42b, and the irradiation optical axis L43b may be aligned in the transport direction X1.

The light source colors of the first light source 31, the second light source 32, and the third light source 33 are various, and may be, for example, infrared color, white color, or ultraviolet color. The light source colors of the first light source 31, the second light source 32, and the third light source 33 may all be the same or different from each other.

As shown in FIG. 3, the first light source 31 may include, for example, a plurality of LED chips 30. Similarly, the second light source 32 and the third light source 33 may include a plurality of LED chips 30. The plurality of LED chips 30 may be arranged in a predetermined direction (here, the Y direction).

(Operation example)
Next, an example of illuminating the appearance inspection object W2 using the lighting device 101 will be described with reference to FIG. FIG. 4 is a schematic view showing an operation example of the lighting device shown in FIG. The surface W2a of the appearance inspection object W2 has a defect W2b. The defect W2b protrudes from the surface W2a.

As shown in FIG. 4, the third illumination light L43 is applied to the defect W2b, and the reflected light L53 is reflected from the defect W2b. The reflected light L53 travels along the optical axis Z1 of the image pickup device 1. The optical axis of the reflected light L53 and the optical axis Z1 of the imaging device 1 are the same axis. Therefore, the third illumination light L43 is substantially the same illumination as the coaxial epi-illumination. The image pickup device 1 can acquire the reflected light L53 by the third illumination light L43 and generate an image having good brightness.

On the other hand, the first illumination light L41 and the second illumination light L42 irradiate the defect W2b, and the reflected lights L51 and L52 are reflected from the defect W2b. The reflected lights L51 and L52 move away from the optical axis Z1 of the image pickup device 1 as they advance. The optical axis of the reflected light L53 and the optical axis Z1 of the imaging device 1 are not the same axis. The first illumination light L41 and the second illumination light L42 do not become coaxial epi-illumination.

Since the defect W2b irradiated to the first illumination light L41, the second illumination light L42, and the third illumination light L43 is inclined with respect to the surface W2a, only the reflected light L53, not the reflected light L51, is present. It is considered that the light traveled along the optical axis Z1 of the image pickup device 1. Further, when the defect W2b is recessed, the second illumination light L42 is substantially the same illumination as the coaxial epi-illumination. Therefore, even if the surface W2a of the appearance inspection object W2 has a defect, either the second illumination light L42 or the third illumination light L43 can be substantially the same illumination as the coaxial epi-illumination. Therefore, the appearance inspection object W2 can be easily illuminated in substantially the same manner as the coaxial epi-illumination. Therefore, the first illumination light L41, the second illumination light L42, and the third illumination light L43 easily illuminate the appearance inspection object in substantially the same manner as the coaxial epi-illumination regardless of the presence or absence of defects. be able to. As a result, it is possible to generate an captured image having good brightness and avoid a decrease in the detection accuracy of the defect W2b on the surface to be inspected. In particular, even when the surface W2a of the appearance inspection object W2 is a mirror surface or is glossy, it is preferable that the detection accuracy of the defect W2b on the surface to be inspected can be prevented from being lowered.

Further, even if each of the above configurations, for example, the appearance inspection objects W1 and W2, the imaging device 1, the half mirror 2, and the light source group 3 are not installed at a predetermined position and orientation with high accuracy, the first illumination light L41 , The second illumination light L42, and the third illumination light L43 can be substantially the same illumination as the coaxial epi-illumination.

(Example of visual inspection equipment)
Next, with reference to FIGS. 5A and 5B, it is a schematic view which shows an example of the appearance inspection apparatus provided with the lighting apparatus which concerns on Embodiment 1. FIG. FIG. 5A is a schematic view showing an example of an appearance inspection device including the lighting device shown in FIG. FIG. 5B is a bottom view showing a main part of an example of the visual inspection apparatus shown in FIG. 5A.

As shown in FIGS. 5A and 5B, the visual inspection device 201 includes a lighting device 101, a CCD sensor 80, and a lens 84. The visual inspection device 201 is a scanner. The CCD sensor 80 is an example of the image pickup device 1 shown in FIG. The CCD sensor 80 includes a CCD substrate 81 and a photoelectric conversion element 82. The photoelectric conversion element 82 is provided on the CCD substrate 81. The photoelectric conversion elements 82 are arranged in a row in a predetermined direction (here, the Y direction).

Here, the first light source 31, the second light source 32, and the third light source 33 use the first illumination light L41, the second illumination light L42, and the third illumination light 43, respectively, as the appearance inspection object W1. The irradiated portion W1b on the surface W1a of the above surface is irradiated, and the reflected lights L51, L52, and L53 are reflected. At least one of the reflected lights L51, L52, and L53 is imaged by the lens 84. Further, at least one of them forms an image on the photoelectric conversion element 82. The photoelectric conversion element 82 outputs an image showing the irradiation site W1b by performing photoelectric conversion.

(Control configuration)
Next, the control configuration of the visual inspection device 201 will be described with reference to FIG. FIG. 6 is a control block diagram of an example of the visual inspection apparatus shown in FIG. 5A.

As shown in FIG. 6, the visual inspection device 201 includes an external synchronization interface 11, an image pickup system control unit 12, a light source control unit 13, an image pickup device control unit 14, an image processing unit 15, and an image interface 16. To be equipped with.

The external synchronization interface 11 acquires an external synchronization signal according to the amount of transportation of the appearance inspection object W1 from the transfer device that conveys the appearance inspection object W1. The external synchronization interface 11 appropriately processes the external synchronization signal and then outputs the external synchronization signal to the imaging system system control unit 12.

The imaging system system control unit 12 acquires an external synchronization signal. The acquired external synchronization signal is, for example, a one-pulse signal generated every time the amount of the appearance inspection object W1 conveyed increases by one line. In such a case, when the transfer device moves the appearance inspection object W1 by one line, the imaging system system control unit 12 acquires a pulse signal from the transfer device. This acquired external synchronization signal corresponds to the rotational displacement of the rotor of the motor when the transport device transports the appearance inspection object W1 using the motor, and is, for example, an encoder signal. The image pickup system system control unit 12 outputs control signals to the light source control unit 13, the image pickup device control unit 14, and the image processing unit 15, respectively, based on the external synchronization signal.

When the light source control unit 13 acquires a control signal from the imaging system system control unit 12, the light source control unit 13 exclusively lights the first light source 31, the second light source 32, and the third light source 33. In other words, the light source control unit 13 controls lighting and extinguishing in the order of the first light source 31, the second light source 32, and the third light source 33. Specifically, the light source control unit 13 turns on only the first light source 31 for a predetermined period of time, and then turns off the first light source 31. Then, the light source control unit 13 turns on only the second light source 32 for a predetermined period of time, and then turns off the second light source 32. Finally, the light source control unit 13 turns on only the third light source 33 for a predetermined period of time, and then turns off the third light source 33. As a result, at least a part of the appearance inspection object W1 is irradiated with the first illumination light L41, the second illumination light L42, and the third illumination light L43, respectively.

The image pickup device control unit 14 acquires a control signal from the image pickup system system control unit 12 at substantially the same timing as the acquisition of the control signal of the light source control unit 13. The image pickup system system control unit 12 sends a drive signal to the image pickup device 1 so that the image pickup device 1 is made to take an image at the same timing as the lighting of the first light source 31, the second light source 32, and the third light source 33. At this time, the image pickup device 1 performs a photoelectric conversion operation for one line at the timing (time point) when the first light source 31, the second light source 32, and the third light source 33 are turned on, and generates image data. .. The image pickup device 1 outputs the generated image data to the image processing unit 15. That is, in this case, when the external synchronization interface 11 acquires the external synchronization signal for one line of the transported amount of the appearance inspection object W1, the image pickup device 1 receives the first light source 31, the second light source 32, and the third light source. Image data for a total of 3 lines for each of the 33 light sources is output to the image processing unit 15. When the appearance inspection object W1 is transported by one line, the image pickup device 1 receives image data for one line by lighting the light sources of the first light source 31, the second light source 32, and the third light source 33. To generate. Therefore, the image data output from the image pickup device 1 corresponds to the data for three lines.

The image processing unit 15 acquires image data from the image pickup device 1, and appropriately performs image processing on the acquired image data.

The image interface 16 is, for example, a camera link, USB (universal serial bus) 3.0, CXP (CoaXPress (registered trademark)), or the like. The image interface 16 acquires image-processed image data from the image processing unit 15. The image interface 16 appropriately processes the acquired image data, and then outputs the image data to, for example, a higher-level inspection system. The higher-level inspection system is, for example, a computer or the like.

(Control method)
Next, a control method of the visual inspection apparatus according to the first embodiment will be described with reference to FIGS. 7A and 7B. 7A and 7B are flowcharts showing a control method of the visual inspection apparatus shown in FIG. 5A.

The visual inspection device 201 is powered on to initialize the system (step ST101). Subsequently, it waits for an imaging start command from the inspection system (step ST102: NO). Upon receiving the imaging start command (step ST102: YES), it waits for the acquisition of the external synchronization signal (step ST103, ST104: NO). In other words, the visual inspection device 201 is on standby. When the external synchronization signal is acquired (step ST104: YES), the control of imaging the amount equivalent to one line of the conveyed amount in the appearance inspection object W1 is started (step ST105). In step ST105, a total of three light sources, the first light source 31, the second light source 32, and the third light source 33, are turned on and off, and the image pickup device 1 is controlled to take an image. After acquiring the image data of a total of three light sources (step ST106: YES), it is determined whether to end or continue the imaging (step ST107). When continuing the imaging (step ST107: NO), the process returns to step ST103. When the imaging is terminated (step ST107: YES), the termination process is performed (step ST108). Then, the process returns to step ST102.

(Timing chart)
Next, with reference to FIG. 8, the operation of each configuration of an example of the visual inspection apparatus according to the first embodiment will be described. FIG. 8 is a timing chart showing the operation of each configuration of an example of the visual inspection apparatus shown in FIG. 5A.

When the appearance inspection object W1 is conveyed for one line, one pulse of an external synchronization signal (here, an encoder signal) is generated. The time corresponding to one line of the transported amount of the appearance inspection object W1 and one cycle of the external synchronization signal are the same.

In one cycle of the external synchronization signal, the light source control unit 13 sequentially and exclusively controls the lighting of the first light source 31, the second light source 32, and the third light source 33.

The imaging system system control unit 12 shown in FIG. 6 sends a drive signal to the imaging device 1 three times in one cycle of the external synchronization signal. In other words, the time corresponding to one line of the conveyed amount of the appearance inspection object W1 is three times the interval of the drive signal ΦTG of the imaging device 1. Each time the image pickup device 1 acquires a drive signal, the image pickup device 1 takes an image of a region corresponding to one line of the conveyed amount in the appearance inspection object W1.

Specifically, when the external synchronization signal is acquired, the appearance inspection object W1 is illuminated by the first light source 31, and the imaging device 1 acquires the first drive signal to carry one line in the appearance inspection object W1. Image the area of the minute. Subsequently, the appearance inspection object W1 is illuminated by the second light source 32, and the imaging device 1 acquires the second drive signal to image the region of the appearance inspection object W1 for one line of the conveyed amount. Further, the appearance inspection object W1 is illuminated by the second light source 32, and the imaging device 1 acquires the third drive signal to image the region of the appearance inspection object W1 for one line of the conveyed amount. When the external synchronization signal is acquired again, the same illumination and imaging are repeated. Therefore, it is possible to acquire an image of the appearance inspection object W1 irradiated to each light source.

(Modification example)
Next, a modification of the lighting device and the visual inspection device according to the first embodiment will be described with reference to FIGS. 9 to 17B.

(Modification example 1)
The lighting device 102 shown in FIG. 9 is a modification of the lighting device 101 shown in FIG. The illuminating device 102 has the same configuration as the illuminating device 101 except that the prism 6 is provided instead of the half mirror 2. Similar to the illumination device 101, the first light source 31 irradiates the appearance inspection object W1 with the first illumination light L41 via the prism 6. Further, the second light source 32 irradiates the appearance inspection object W1 with the second illumination light L42 via the prism 6. Further, the third light source 33 irradiates the appearance inspection object W1 with the third illumination light L43 via the prism 6.

According to the configuration of the illuminating device 102, similarly to the illuminating device 101, even if the surface W2a of the appearance inspection object W2 shown in FIG. 4 has a defect W2b, the appearance inspection object W2 can be easily coaxial epi-illumination. Substantially the same lighting can be achieved. Since it is possible to easily perform substantially the same illumination as the coaxial epi-illumination, it is possible to generate an image with good brightness and avoid a decrease in the detection accuracy of the defect W2b on the surface to be inspected. can.

(Modification 2)
There is a modification of the lighting device 101 having the same configuration as the lighting device 101 shown in FIG. 1 except for the light source group. The modified example includes the light source group 3a shown in FIG. The light source group 3a shown in FIG. 10 is a modification of the light source group 3 shown in FIG. The light source group 3a has the same configuration as the light source group 3 except for the directions of the second light source 32 and the third light source 33.

The outgoing light axis L42a is inclined and extends in a direction away from the outgoing light axis L41a. The outgoing light axis L43a is inclined and extends in a direction away from the outgoing light axis L41a. The angular relationship between the light source group 3a and the half mirror 2 may be the same as the angular relationship between the light source group 3 and the half mirror 2 shown in FIG. Specifically, the illumination angle β12 formed by the intersection of the irradiation optical axis L42b and the irradiation optical axis L41b may be in the range of more than 0 (zero) degrees and 5 degrees or less. The angle α32a formed by the intersection of the emission light axis L42a and the emission light axis L41a in the light source group 3a may be determined so that the illumination angle β12 is within the above range. The illumination angle β13 formed by the intersection of the irradiation optical axis L43b and the irradiation optical axis L41b may be in the range of more than 0 (zero) degrees and 5 degrees or less. The angle α33a formed by the intersection of the emission light axis L43a and the emission light axis L41a in the light source group 3a may be determined so that the illumination angle β13 is within the above range. For example, the angle α32a in the light source group 3a is the same as the angle α33 in the light source group 3. The angle α33a in the light source group 3a is the same as the angle α32 in the light source group 3.

(Modification example 3)
The lighting device 101a shown in FIG. 11 is a modification of the lighting device 101 shown in FIG. The lighting device 101a has the same configuration as the lighting device 101 except for the light source group 3b.

The light source group 3b includes a first light source 31b, a second light source 32b, and a third light source 33b. The first light source 31b has the same configuration as the first light source 31 except for its direction and the first illumination light. Similarly, the second light source 32b has the same configuration as the second light source 32, except for its orientation and the second illumination light. Similarly, the third light source 33b has the same configuration as the third light source 33, except for its orientation and the third illumination light.

The illumination light L44 of the first light source 31b has a lower directivity than the illumination light L41 of the first light source 31 shown in FIG. In other words, the luminous flux of the illumination light L44 is greatly spread as compared with the luminous flux of the illumination light L41. Similarly, the illumination light L45 of the second light source 32b has a lower directivity than the illumination light L42 of the second light source 32 shown in FIG. In other words, the luminous flux of the illumination light L45 is greatly spread as compared with the luminous flux of the illumination light L42. Similarly, the illumination light L46 of the third light source 33b has a lower directivity than the illumination light L43 of the third light source 33 shown in FIG. In other words, the luminous flux of the illumination light L46 is much wider than the luminous flux of the illumination light L43.

The first light source 31b may be arranged so that the emission light axis L41a of the illumination light L41 shown in FIG. 1 enters the inside of the luminous flux of the illumination light L44 of the first light source 31b. Similarly, the second light source 32b may be arranged so that the emission light axis L42a of the illumination light L42 shown in FIG. 1 enters the inside of the luminous flux of the illumination light L45 of the second light source 32b. Similarly, the third light source 33b may be arranged so that the emission light axis L43a of the illumination light L43 shown in FIG. 1 enters the inside of the luminous flux of the illumination light L46 of the third light source 33b.

As shown in FIG. 12, the emission light axis L45a of the second illumination light L45 and the emission light axis L46a of the third illumination light L46 may be parallel to the emission light axis L44a of the first illumination light L44. The luminous flux of the first illumination light L44, the second illumination light L45, and the third illumination light L46 spreads. Therefore, the luminous fluxes of the first illumination light L44, the second illumination light L45, and the third illumination light L46 are the light beams along the irradiation light axis L41b, the irradiation light axis L42b, and the irradiation light axis L43b shown in FIG. Includes each. Even if the emission light axis L45a and the emission light axis L46a are parallel to the emission light axis L44a, the second illumination light L45 and the third illumination light L46 have an illumination angle β12 and an illumination angle β13, respectively. Includes light rays in the range above 0 (zero) degrees and below 5 degrees.

Therefore, similarly to the illuminating device 101, the appearance inspection object is subjected to the first illumination light L44, the second illumination light L45, and the third illumination light L46 regardless of the presence or absence of defects on the surface of the appearance inspection object. It is possible to easily perform substantially the same illumination as coaxial epi-illumination. Therefore, it is possible to generate an captured image having good brightness and avoid a decrease in the detection accuracy of defects on the surface to be inspected.

The first light source 31 may include, for example, a plurality of LED chips 30a shown in FIGS. 13 to 15. Similarly, the second light source 32 and the third light source 33 may include a plurality of LED chips 30a. The LED chip 30a emits illumination light 312 from the exit surface 311 along the emission light axis 313. The luminous flux of the illumination light 312 spreads. Specifically, the outer edge of the light flux of the illumination light 312 departs from the emission optical axis 313 as it travels from the emission surface 311. The luminous flux of the illumination light 312 is much wider than the luminous flux of the illumination light of the LED chip 30 shown in FIG.

Therefore, the orientation of the first light source 31b has a wider range than the orientation of the first light source 31 shown in FIG. Therefore, the first light source 31b has a lower required installation accuracy than the first light source 31, and can be easily installed. Similarly, the orientation of the second light source 32b has a wider range than the orientation of the second light source 32 shown in FIG. Therefore, the second light source 32b has a lower required installation accuracy than the second light source 32 and can be easily installed. Similarly, the orientation of the third light source 33b has a wider range than the orientation of the third light source 33 shown in FIG. Therefore, the third light source 33b has lower required installation accuracy than the third light source 33 and can be easily installed. From the above, the light source group 3b may be easily installed as compared with the light source group 3 shown in FIG.

(Modification example 4)
The lighting device 102a shown in FIG. 16 is a modification of the lighting device 101a shown in FIG. The illuminating device 102a has the same configuration as the illuminating device 101a except that the prism 6 is provided instead of the half mirror 2. Similar to the illumination device 101a, the first light source 31b irradiates the appearance inspection object W1 with the first illumination light L44 via the prism 6. Further, the second light source 32b irradiates the appearance inspection object W1 with the second illumination light L45 via the prism 6. Further, the third light source 33b irradiates the appearance inspection object W1 with the third illumination light L46 via the prism 6.

According to the configuration of the illuminating device 102a, similarly to the illuminating device 101a, even if the surface W2a of the appearance inspection object W2 shown in FIG. 4 has a defect W2b, the appearance inspection object W2 can be easily coaxial epi-illumination. Substantially the same lighting can be achieved. Since it is possible to easily perform substantially the same illumination as the coaxial epi-illumination, it is possible to generate an image with good brightness and avoid a decrease in the detection accuracy of the defect W2b on the surface to be inspected. can.

(Modification 5)
The visual inspection device 202 shown in FIG. 17A is a modification of the visual inspection device 201 shown in FIG. 5A. The visual inspection device 202 has the same configuration as the visual inspection device 201 except for the imaging device. The CCD sensor 280 is an example of the image pickup device 1 shown in FIG. As shown in FIG. 17B, the CCD sensor 280 includes a CCD substrate 81 and a photoelectric conversion element group 85. The photoelectric conversion element group 85 is provided on the CCD substrate 81. The photoelectric conversion element group 85 includes photoelectric conversion element rows 85a, 85b, and 85c. The photoelectric conversion element rows 85a, 85b, and 85c are a plurality of photoelectric conversion elements arranged in a row in a predetermined direction (here, the Y direction). The photoelectric conversion element trains 85a, 85b, and 85c are arranged in parallel.

Here, the first light source 31, the second light source 32, and the third light source 33 use the first illumination light L41, the second illumination light L42, and the third illumination light 43, respectively, as the appearance inspection object W1. The irradiated portion W1b on the surface W1a of the above surface is irradiated, and the reflected lights L51, L52, and L53 are reflected. At least one of the reflected lights L51, L52, and L53 is imaged by the lens 84. Further, at least one of them forms an image on the photoelectric conversion element group 85, that is, the photoelectric conversion element rows 85a, 85b, 85c. The photoelectric conversion element group 85 outputs an image showing the irradiation site W1b by photoelectric conversion. Specifically, the photoelectric conversion element trains 85a, 85b, and 85c output images showing different lines or areas at the irradiation site W1b, respectively. Therefore, the visual inspection device 202 can output images showing three different lines or areas by one imaging.

(Other embodiments, etc.)
Further, the lighting devices 101, 101a, 102, 102a and the visual inspection devices 201, 202 according to the above embodiment can be provided with the following hardware configurations. FIG. 18 is a diagram showing an example of the hardware configuration included in the lighting devices 101 and 102 and the visual inspection devices 201 and 202. As described in the procedures for processing in the lighting devices 101, 101a, 102, 102a, and the visual inspection devices 201, 202 in the various embodiments described above, the present invention may also take a form as a processing method.

The lighting device 300 shown in FIG. 18 includes a processor 301 and a memory 302 together with the interface 303. The control configuration (see FIG. 6) of the visual inspection device 201 described in the above-described embodiment is realized by the processor 301 reading and executing the control program stored in the memory 302. That is, this program is a program for causing the processor 301 to function as a control configuration of the visual inspection device 201, for example, an imaging system system control unit 12, or a part thereof. It can be said that this program is a program for causing the visual inspection device 201 of FIG. 6 to execute the processing in the control configuration or a part thereof.

The programs described above are stored using various types of non-transitory computer readable medium and can be supplied to a computer (a computer including an information notification device). Non-transient computer-readable media include various types of tangible storage media. Examples of non-temporary computer-readable media include magnetic recording media (eg, flexible disks, magnetic tapes, hard disk drives), magneto-optical recording media (eg, magneto-optical disks). Further, this example includes a CD-ROM (Read Only Memory), a CD-R, and a CD-R / W. Further, this example includes semiconductor memories (eg, mask ROM, PROM (Programmable ROM), EPROM (Erasable PROM), flash ROM, RAM (Random Access Memory)). The program may also be supplied to the computer by various types of transient computer readable medium. Examples of temporary computer-readable media include electrical, optical, and electromagnetic waves. The temporary computer-readable medium can supply the program to the computer via a wired communication path such as an electric wire and an optical fiber, or a wireless communication path.

Furthermore, as described in the various embodiments described above, the procedure for processing in the visual inspection device, the present disclosure may also take a form as a control method for the lighting device and the visual inspection device. Further, it can be said that the above-mentioned program is a program for causing the lighting device and the visual inspection device to execute such a control method.

The present invention is not limited to the above embodiment, and can be appropriately modified without departing from the spirit.

101, 101a, 102, 102a Lighting equipment 201, 202 Visual inspection equipment 1 Imaging device 2 Half mirror 3, 3a, 3b Light source group
31, 31b, 32, 32b, 33, 33b Light source 6 Prism 11 External synchronization interface 12 Imaging system system control unit 13 Light source control unit 14 Imaging device control unit 15 Image processing unit 16 Image interface 80, 280 CCD sensor 81 CCD substrate 82 Photoelectric Conversion element 84 Lens 85 Photoelectric conversion element group 85a, 85b, 85c Photoelectric conversion element row 300 Lighting device 301 Processor 302 Memory 303 Interface 311 Emission surface 312 Illumination light 313 Emission light axis L41, L44 First illumination light L41a, L44a Emission light Axis L41b Irradiation light axis L42, L45 Second illumination light L42a, L45a Emission light axis L42b Irradiation light axis L43, L46 Third illumination light L43a, L46a Emission light axis L43b Irradiation light axis L5, Z7 Optical axis L51, L52, L53 Reflected light ST101, ST102, ST103, ST104, ST105, T106, ST107, ST108 Step W1, W2 Appearance inspection object W1a, W2a Surface W1b Irradiation site W2b Defect X1 Transport direction α32, α32a, α33, α33a Angle β12, β13 Illumination angle

Claims (8)

The first light source and
The second and third light sources provided in the vicinity of the first light source, and
Equipped with a light source control unit
The first light source irradiates the appearance inspection object with the first illumination light through a half mirror or a prism.
The first illumination light is coaxial epi-illumination having an irradiation optical axis that is the same axis as the optical axis of the imaging optical system that forms an image of the appearance inspection object.
The second and third light sources irradiate the appearance inspection object with the second and third illumination lights via the half mirror or the prism, respectively.
The irradiation optical axes of the second and third illumination lights intersect with the illumination emission axes of the first illumination light, respectively.
The light source control unit exclusively lights the first, second, and third light sources.
Lighting device. The irradiation optical axis of the first illumination light is located between the irradiation optical axes of the second and third illumination lights.
The lighting device according to claim 1. The irradiation optical axes of the first, second, and third illumination lights are aligned in the direction in which the appearance inspection object is conveyed.
The lighting device according to claim 1 or 2. The light source control unit exclusively lights the first light source, the second light source, and the third light source, thereby causing the first illumination light, the second illumination light, and the third light source. Irradiates at least a part of the appearance inspection object with the illumination light of
The lighting device according to any one of claims 1 to 3. The light source colors of the first, second, and third light sources are different.
The lighting device according to any one of claims 1 to 4. Lighting equipment and
Equipped with an imaging unit
The lighting device is
A first light source, second and third light sources provided in the vicinity of the first light source, and a light source control unit are provided.
The first light source irradiates the appearance inspection object with the first illumination light through a half mirror or a prism.
The first illumination light is coaxial epi-illumination having an incident optical axis that is the same axis as the optical axis of the imaging optical system that forms an image of the appearance inspection object.
The second and third light sources irradiate the appearance inspection object with the second and third illumination lights via the half mirror or the prism, respectively.
The incident optical axes of the second and third illumination lights intersect with the incident optical axes of the first illumination light, respectively.
The light source control unit exclusively lights the first light source and the second and third light sources.
When the light source control unit exclusively lights the first light source and the second and third light sources, the image pickup unit takes an image of the appearance inspection object and lights only the first light source. An image captured when only the second light source is turned on, an image captured when only the third light source is turned on, and an image captured when only the third light source is turned on are generated.
Visual inspection equipment. The first light source and
A second and third light sources provided in the vicinity of the first light source are provided.
The first light source irradiates the appearance inspection object with the first illumination light through a half mirror or a prism.
The first illumination light is coaxial epi-illumination having an irradiation optical axis that is the same axis as the optical axis of the imaging optical system that forms an image of the appearance inspection object.
The second and third light sources irradiate the appearance inspection object with the second and third illumination lights via the half mirror or the prism, respectively.
In the method of controlling the illumination device, the irradiation optical axes of the second and third illumination lights intersect with the illumination emission axes of the first illumination light, respectively.
Including the step of exclusively turning on the first, second and third light sources.
How to control the lighting device. The first light source and
A second and third light sources provided in the vicinity of the first light source are provided.
The first light source irradiates the appearance inspection object with the first illumination light through a half mirror or a prism.
The first illumination light is coaxial epi-illumination having an irradiation optical axis that is the same axis as the optical axis of the imaging optical system that forms an image of the appearance inspection object.
The second and third light sources irradiate the appearance inspection object with the second and third illumination lights via the half mirror or the prism, respectively.
The irradiation optical axes of the second and third illumination lights are used in a computer that operates as an illumination device that intersects the illumination emission axes of the first illumination light.
The step of exclusively turning on the first, second, and third light sources is executed.
program.

Images