TWI721720B - Light source device and optical inspection system - Google Patents

Abstract

A light source device adapted to provide an inspection beam is provided. The light source device includes a housing, a plurality of first light illuminating elements, and a plurality of light guiding structures. The housing has a light exiting port, and a first accommodating space. The plurality of first illuminating elements are disposed in the first accommodating space and are adapted to provide a plurality of first light beams. The plurality of light guiding structures are disposed in the first accommodating space, wherein the plurality of first illuminating elements respectively correspond to the plurality of light guiding structures, and the plurality of light guiding structures respectively guide the plurality of first light beams to be transmitted in different directions. The first light beams are transmitted out of the light exiting port to form the inspection light beam.

Description

Light source device and optical detection system

The present invention relates to a light source device and an optical detection system using the light source device, and more particularly to a light source device for measuring a hole-shaped structure and an optical detection system using the light source device.

Automated Optical Inspection (AOI) uses machine vision as the inspection standard technology to replace traditional human eye recognition through machine vision to achieve high-precision and high-efficiency inspections. As an improvement on the shortcomings of the traditional use of optical instruments for inspection by humans, the application level includes the research and development of high-tech industries, manufacturing quality control, national defense, people's livelihood, medical treatment, environmental protection, electric power and other fields.

In the field of optical inspection, it is more difficult to detect complex surfaces than smooth surfaces. Generally, complex surfaces with visibility depend on the depth of field of the image capture device. If the depth of field of the image capture device is sufficient, it can generally be overcome. In contrast, for the defects that are not visible on the plane (such as blind holes, perforated inner wall surface defects), it is difficult to detect by traditional optical methods (such as plane shooting). Such defects usually need to be opposed to the image capture device. The position and shooting angle must be adjusted, and each target area must be shot one by one, so that this type of detection is very time-consuming and labor-intensive, and it is difficult to achieve the corresponding efficiency.

The invention provides a light source device and an optical detection system, which can sense image information with different characteristics for analysis and comparison of objects to be tested.

The present invention provides a light source device suitable for providing a detection beam. The light source device includes a housing, a plurality of first light-emitting elements, and a plurality of light guide structures. The shell has a light outlet and a first accommodating space. The plurality of first light-emitting elements are arranged in the first accommodating space and are suitable for providing a plurality of first light beams. The plurality of light guide structures are arranged in the first accommodating space, wherein the plurality of first light emitting elements respectively correspond to the plurality of light guide structures, and the plurality of light guide structures respectively guide the plurality of first light beams to pass in different directions. The multiple first light beams are passed out of the light exit to form a detection light beam.

The present invention also provides an optical detection system, which is suitable for measuring an object to be tested. The optical detection system includes a light source device, an image capture device, and a processing device. The light source device is suitable for providing a detection beam. The light source device includes a housing, a plurality of first light-emitting elements, and a plurality of light guide structures. The shell has a light outlet and a first accommodating space. The plurality of first light-emitting elements are arranged in the first accommodating space and are suitable for providing a plurality of first light beams. A plurality of light guide structures are arranged in the first accommodating space, wherein the first light emitting elements respectively correspond to the light guide structures, and the light guide structures respectively guide the first light beams to pass in different directions. The image capturing device is arranged on the transmission path of the detection beam reflected by the object to be tested to capture an image of the object to be tested. The processing device is electrically connected to the image capturing device for image analysis of the image of the object to be tested to obtain a detection result of the object to be tested, wherein the first light beam is transmitted out of the light outlet to form a detection light beam.

The present invention also provides a light source device suitable for providing a detection beam. The light source device includes a housing, a light guide structure, a plurality of first light-emitting elements, a plurality of second light-emitting elements, and a light splitting element. The shell has a light outlet, a first accommodating space and a second accommodating space. The light guide structure is disposed in the first accommodating space, and has a reflective curved surface and a third accommodating space. The plurality of first light-emitting elements are arranged in the third accommodating space, and are suitable for providing the plurality of first light beams to the reflective curved surface. The plurality of second light-emitting elements are arranged in the second accommodating space and are suitable for providing a second light beam. The light splitting element is arranged on the transmission path of the second light beam, wherein the first light beam and the second light beam are transmitted out of the light outlet to form a detection light beam, and the reflective curved surface is suitable for reflecting the first light beam so that the transmission directions of the transmitted light outlet are different.

The present invention also provides an optical detection system, which is suitable for measuring an object to be tested. The optical detection system includes a light source device, an image capture device, and a processing device. The light source device is suitable for providing a detection beam to the object to be tested. The light source device includes a housing, a light guide structure, a plurality of first light-emitting elements, a plurality of second light-emitting elements, and a light splitting element. The shell has a light outlet, a first accommodating space and a second accommodating space. The light guide structure is disposed in the first accommodating space, and has a reflective curved surface and a third accommodating space. The plurality of first light-emitting elements are arranged in the third accommodating space, and are suitable for providing the plurality of first light beams to the reflective curved surface. The plurality of second light-emitting elements are arranged in the second accommodating space and are suitable for providing a second light beam. The light splitting element is arranged on the transmission path of the second light beam. The image capturing device is arranged on the transmission path of the detection beam reflected by the object to be tested. The processing device is electrically connected to the image capturing device, wherein the first light beam and the second light beam are transmitted out of the light outlet to form a detection light beam, and the reflective curved surface is adapted to reflect the first light beam so that the transmission directions of the light transmitted through the light outlet are different.

Based on the above, in the light source device and the optical detection system of the present invention, a plurality of first light-emitting elements are arranged in the first accommodating space of the housing, and a plurality of light guide structures are used to provide a plurality of first light beams. A light-emitting element respectively corresponds to the light-guiding structure, and the light-guiding structure respectively guides the first light beam to pass in different directions. In this way, when the object to be tested is sensed, a plurality of first beams can be provided to different areas of the object to be tested, so that different areas can present different image frames respectively, and then can be sensed with different characteristics Image information for the analysis and comparison of the object under test. In addition, compared with the conventional spatial configuration of the coaxial light framework, the design of the light guide structure enables the first light-emitting elements to be further concentratedly arranged in the first accommodating space in the housing whose extending direction is perpendicular to the optical axis direction. Therefore, other components can be arranged in the space perpendicular to the optical axis direction, and the working distance between the light source device and the image capturing device in the optical detection system can be shortened. At the same time, this design can save configuration space and make the light source device smaller.

In order to make the above-mentioned features and advantages of the present invention more comprehensible, the following specific embodiments are described in detail in conjunction with the accompanying drawings.

FIG. 1 is a schematic cross-sectional view of an optical detection system according to an embodiment of the present invention. 2 is a partial schematic diagram of the optical inspection system measuring an object to be tested according to an embodiment of the present invention. FIG. 3 is a three-dimensional schematic diagram of the light source device in FIG. 1. Please refer to Figure 1 to Figure 3. For the convenience of description, FIG. 3 only shows part of the structure, not the appearance of the physical structure. This embodiment provides an optical inspection system 10 suitable for measuring an object 20 to be tested. In detail, the object under test 20 is, for example, a circuit board and has a hole structure. The hole structure has a bottom surface area A1 and a side wall area A2. The optical detection system 10 is adapted to use the light source device 100 to provide two different optical characteristics (such as optical characteristics such as collimation, wavelength, optical signal intensity, incident angle, etc.) to the bottom area A1 of the object under test 20 and The side wall area A2 allows the bottom surface area A1 and the side wall area A2 to respectively present different image frames during exposure, so that image information with different characteristics can be sensed for analysis and comparison of the object 20 under test.

The optical inspection system 10 includes a light source device 100, an image capturing device 50 and a processing device 60. The image capturing device 50 is disposed on the light transmission path reflected by the object 20 to be tested, and is used to capture the light reflected by the object 20 to be tested to obtain an image. The image capture device 50 includes, for example, a photosensitive element such as a charge coupled device (CCD) or a complementary metal oxide semiconductor (CMOS), but the invention is not limited thereto.

The processing device 60 is electrically connected to the image capturing device 50 for receiving images captured by the capturing device 50 for image detection. The processing device 60 is a central processing unit (CPU), a microprocessor (microprocessor), a digital signal processor (DSP), a programmable controller, and a programmable logic device (programmable logic device, PLD) or other similar devices or combinations of these devices are not limited by the present invention.

The light source device 100 is adapted to provide a detection beam L to the object 20 to be tested. In detail, the light source device 100 includes a housing 110, a plurality of first light-emitting elements 120, a dichroic element 130, and a plurality of second light-emitting elements 140. The housing 110 has a light outlet O1, a first accommodating space E1, and a second accommodating space E2 spaced apart from each other for accommodating the first light-emitting element 120, the light splitting element 130, and the second light-emitting element 140 mentioned above. Specifically, in this embodiment, there is an opening O2 between the first accommodating space E1 and the second accommodating space E2 for allowing the light beams in the first accommodating space E1 and the second accommodating space E2 to borrow Pass and pass through the opening O2. At the edge of the opening O2, the first accommodating space E1 and the second accommodating space E2 can be further separated by a partition or a middle frame, as shown in FIG. 1, but the present invention is not limited to this. On the other hand, the side of the second accommodating space E2 opposite to the first accommodating space E1 has an opening O3 for transmitting the light reflected by the object under test 20 to the image capturing device 50 through the opening O3.

The plurality of second light-emitting elements 140 are arranged in the second accommodating space E2 and are suitable for providing a second light beam L2, and the light splitting element 130 is arranged on the transmission path of the second light beam L2. In this embodiment, the second light-emitting element 140 is, for example, a light-emitting diode (LED) or a laser diode (LD) or other light-emitting device, but the invention is not limited to this. In this embodiment, the light source device 100 further includes a collimating lens group 160, which is disposed in the second accommodating space E2 and the transmission path of the second light beam L2. Therefore, the second light beam L2 emitted by the second light-emitting element 140 passes through the collimating lens group 160 to form collimated light, and is reflected by the beam splitting element 130 and transmitted through the first accommodating space E1 to the object under test 20, for example, The bottom area A1 of the object 20 to be tested is illuminated. It should be noted here that the so-called collimated light here refers to a light beam with certain collimation characteristics, that is, a light beam that does not have a large divergence or focusing characteristic, rather than an absolutely collimated light beam. In other embodiments, different collimating lens groups 160 can pass the second light beam L2 emitted by the second light-emitting element 140 to achieve effects such as divergence, focusing, or intensity adjustment.

The plurality of first light-emitting elements 120 are disposed in the first accommodating space E1, and are suitable for providing a plurality of first light beams L1, wherein the transmission directions of the first light beams L1 transmitted out of the light outlet O1 are all different. In other words, the transmission directions of the multiple first light beams L1 in the housing 110 are also different. In more detail, the light source device 100 further includes a plurality of light guide structures 150 disposed in the first accommodating space E1, wherein the first light emitting elements 120 respectively correspond to the light guide structures 150, and the light guide structures 150 respectively guide the first The light beam L1 is transmitted in different directions. The light guide structure 150 is, for example, a plate-shaped structure, an optical fiber, or is made of a material with diffusion characteristics, and the present invention is not limited thereto. In other words, the first light-emitting element 120 can guide the first light beam L1 to a region that is difficult to irradiate by the shape of the light guide structure 150, and the light guide structure 150 forms a diffused light to illuminate the object 20 under test. , For example, illuminate the sidewall area A2 of the object 20 to be tested.

Therefore, the first light beam L1 and the second light beam L2 pass through the light exit O1 to form the detection light beam L, and in the detection light beam L, the optical characteristics of the first light beam L1 and the second light beam L2 are different. The first light-emitting element 120 may be the same or different light-emitting device as the second light-emitting element 140, and the present invention is not limited thereto. The detection light beam L is transmitted to the object 20 to be tested, and is sequentially transmitted through the light exit port O1, the opening O2, and the opening O3 to the image capturing device 50 by the reflection of the object to be tested 20 for sensing.

In other embodiments, the optical difference between the first light beam L1 and the second light beam L2 may be, for example, that the wavelength of the first light beam L1 is different from the wavelength of the second light beam L2. Alternatively, the luminous intensity of the first light beam L1 is different from the luminous intensity of the second light beam L2. In different embodiments, the first light-emitting element 120 and the second light-emitting element 140 of different types or optical characteristics can be configured for different types of the object to be tested 20 or its hole characteristics. The present invention does not limit the first light beam. The optical characteristics of L1 and the second light beam L2 are different types. In this way, when the object under test 20 is sensed, the first light beam L1 and the second light beam L2 can be provided to the sidewall area A2 and the bottom area A1 of the object under test 20, respectively, so that the bottom area A1 and the sidewall area A2 are Different image frames are presented respectively, and image information with different characteristics (for example, different brightness) can be sensed for analysis and comparison of the object 20 under test. In addition, compared with the conventional spatial configuration of the coaxial light structure, the light guide structure 150 of this embodiment can be designed for the first light emitting element 120 in the same area, so that the first light emitting element 120 provided by the first light emitting element 120 The light beam L1 can be transmitted out of the housing 110 at different angles. In addition, the design of the light guide structure 150 enables the first light emitting element 120 to be further concentratedly arranged in the first accommodating space E1 in the housing 110 whose extending direction is perpendicular to the optical axis direction, so that other elements can be arranged perpendicular to the optical axis. In the space of the direction, the working distance between the light source device 100 and the image capturing device 50 in the optical detection system 10 can be shortened. At the same time, such a design can save configuration space and make the light source device 100 smaller in size.

In detail, in this embodiment, one part of the first light-emitting element 120 is located on a plane B1, and another part of the first light-emitting element 120 is located on another plane B2, and the directions of the two planes are Parallel to each other, as shown in Figure 1. In this way, in addition to reducing the volume of the light source device 100, a heat sink can be easily configured to dissipate the above-mentioned two parts of the first light-emitting element 120, thereby achieving the advantage of simple configuration. In other words, the light source device 100 may further include two heat dissipation devices 170 respectively configured to be connected to one part of the first light emitting element 120 and the other part of the first light emitting element 120. As shown in FIG. 3, the first light-emitting element 120 and the second light-emitting element 140 may each have a circuit substrate, so that the heat sink 170 (shown on the left side only) can be conveniently arranged on the first light-emitting element 120 and the second light-emitting element. Element 140 on.

4 is a schematic cross-sectional view of an optical detection system according to another embodiment of the invention. Please refer to Figure 2 and Figure 4 at the same time. The optical detection system 10A of this embodiment is similar to the optical detection system 10 of FIG. 1. The difference between the two is that in this embodiment, the light source device 100A of the optical detection system 10A is different from the light source device 100 in FIG. 1. In detail, in this embodiment, the light guide structure 150A of the light source device 100A has a reflective curved surface S and a third accommodating space E3. The plurality of first light-emitting elements 120 are disposed in the third accommodating space E3, and are suitable for providing a plurality of first light beams L1 to the reflective curved surface S, wherein the reflective curved surface S is suitable for reflecting the first light beam L1 so as to transmit the light exiting port O1. The directions are all different. The dome of the light guide structure 150A has an opening O4 for allowing light reflected by the object 20 to be measured to pass through the opening O3 to the image capturing device 50 through the opening O4.

In detail, in this embodiment, the first light emitting element 120 is located on the same plane B3 and faces the same direction, that is, provides the first light beam L1 upward. Therefore, the first light beam L1 can be reflected by the reflective curved surface S to be transmitted in different directions, and then can be guided to areas that are harder to irradiate, and the reflective curved surface S forms diffused light to illuminate the object 20 under test, for example, The side wall area A2 of the object 20 to be tested is illuminated. In this way, when the object under test 20 is sensed, the second light beam L2 and the first light beam L1 can be provided to the bottom surface area A1 and the side wall area A2 of the object under test 20 respectively, so that the bottom surface area A1 and the side wall area A2 are Different image frames are presented respectively, and image information with different characteristics (for example, different brightness) can be sensed for analysis and comparison of the object 20 under test.

In addition, it is worth mentioning that in this embodiment, the first light-emitting elements 120 can be respectively arranged on two same areas of the plane B3, for example, in a light bar arrangement, as shown in FIG. 4. In this way, the heat sink can be easily configured to dissipate the two parts of the first light-emitting element 120, thereby achieving the advantage of simple configuration. In other words, the light source device 100 may further include two heat dissipation devices 170 respectively configured to be connected to one part of the first light emitting element 120 and the other part of the first light emitting element 120.

In summary, in the light source device and the optical detection system of the present invention, a plurality of first light-emitting elements are arranged in the first accommodating space of the housing, and a plurality of light guide structures are used to provide a plurality of first light beams, The first light-emitting elements respectively correspond to the light guide structure, and the light guide structure respectively guides the first light beam to pass in different directions. In this way, when the object to be tested is sensed, a plurality of first beams can be provided to different areas of the object to be tested, so that different areas can present different image frames respectively, and then can be sensed with different characteristics Image information for the analysis and comparison of the object under test. In addition, compared with the conventional spatial configuration of the coaxial light framework, the design of the light guide structure enables the first light-emitting elements to be further concentratedly arranged in the first accommodating space in the housing whose extending direction is perpendicular to the optical axis direction. Therefore, other components can be arranged in the space perpendicular to the optical axis direction, and the working distance between the light source device and the image capturing device in the optical detection system can be shortened. At the same time, this design can save configuration space and make the light source device smaller.

Although the present invention has been disclosed in the above embodiments, it is not intended to limit the present invention. Anyone with ordinary knowledge in the relevant technical field can make some changes and modifications without departing from the spirit and scope of the present invention. The scope of protection of the present invention shall be determined by the scope of the attached patent application.

10.10A: Optical inspection system 20: Object to be tested 50: Image capture device 60: processing device 100, 100A: light source device 110: shell 120: The first light-emitting element 130: Spectroscopic element 140: second light-emitting element 150, 150S: light guide structure 160: collimating lens group 170: heat sink A1: Bottom area A2: Sidewall area B1, B2, B3: plane E1: The first housing space E2: Second housing space E3: Third housing space L: detection beam L1: First beam L2: second beam O1: Optical port O2, O3, O4: opening S: reflective surface

FIG. 1 is a schematic cross-sectional view of an optical detection system according to an embodiment of the present invention. 2 is a partial schematic diagram of the optical inspection system measuring an object to be tested according to an embodiment of the present invention. FIG. 3 is a three-dimensional schematic diagram of the light source device in FIG. 1. 4 is a schematic cross-sectional view of an optical detection system according to another embodiment of the invention.

10: Optical inspection system

20: Object to be tested

50: Image capture device

60: processing device

100: light source device

110: shell

120: The first light-emitting element

130: Spectroscopic element

140: second light-emitting element

150: light guide structure

160: collimating lens group

170: heat sink

B1, B2: plane

E1: The first housing space

E2: Second housing space

L: detection beam

L1: First beam

L2: second beam

O1: Optical port

O2, O3: opening

Claims (15)

A light source device suitable for providing a detection beam includes: a housing with a light exit, a first accommodating space, and a second accommodating space spaced apart from the first accommodating space; a plurality of firsts A light-emitting element is arranged in the first accommodating space and is suitable for providing a plurality of first light beams; a plurality of light guide structures are arranged in the first accommodating space; and a plurality of second light-emitting elements are arranged in the second accommodating space The set space is suitable for providing a second light beam; wherein the first light-emitting elements respectively correspond to the light guide structures, and the light guide structures respectively guide the first light beams to pass in different directions, and the first light-emitting elements respectively correspond to the light guide structures. The light beam is passed out of the light outlet to form the detection light beam with the second light beam. In the light source device described in claim 1, wherein one part of the first light-emitting elements is located on a plane, another part of the first light-emitting elements is located on another plane, and the The directions of the two planes are parallel to each other. The light source device described in the first item of the scope of patent application further includes: two heat dissipation devices respectively configured and connected to one part of the first light-emitting elements and another part of the first light-emitting elements. The light source device described in item 1 of the scope of patent application further includes: a light splitting element arranged on the transmission path of the second light beam. According to the light source device described in claim 1, wherein the first light beams are diffuse light, and the second light beams are collimated light. According to the light source device described in claim 1, wherein the wavelength of the first light beams is different from the wavelength of the second light beam or the luminous intensity of the first light beams is different from the luminous intensity of the second light beam. The light source device described in item 1 of the scope of patent application further includes: a collimating lens group disposed on the second accommodating space and the transmission path of the second light beam. According to the light source device described in claim 1, wherein the first accommodating space is located between the second accommodating space and the light exit, and the second light beam passes through the first accommodating space. According to the light source device described in item 1 of the scope of patent application, the light guide structures are composed of at least one of a plate structure, an optical fiber, or a material with diffusing properties. An optical detection system, suitable for measuring an object to be tested, includes: a light source device, adapted to provide a detection beam to the object to be tested, including: a housing with a light outlet, a first accommodating space, and A second accommodating space in which the first accommodating space is spaced apart; a plurality of first light-emitting elements are arranged in the first accommodating space and adapted to provide a plurality of first light beams; a plurality of light guide structures are arranged in the first accommodating space A first accommodating space; and a plurality of second light-emitting elements arranged in the second accommodating space, adapted to provide a second light beam; wherein the first light-emitting elements correspond to the light guide structures, and the The light guide structure respectively guides the first light beams to pass in different directions; An image capture device is arranged on the transmission path of the detection beam reflected by the object to be tested to capture an image of the object to be tested; and a processing device is electrically connected to the image capture device for The image of the object to be measured is analyzed with an image to obtain a detection result of the object to be measured, wherein the first light beams pass through the light exit port to form the detection light beam with the second light beam. According to the optical detection system described in claim 10, the light source device further includes a beam splitting element disposed on the transmission path of the second light beam, the object to be tested has a hole structure, and the hole structure has a A bottom surface area and a side wall area, the second light beam is transmitted to the bottom surface area, and the first light beams are transmitted to the side wall area. A light source device suitable for providing a detection beam includes: a housing with a light exit, a first accommodating space, and a second accommodating space; a light guide structure arranged in the first accommodating space, It has a reflective curved surface and a third accommodating space; a plurality of first light-emitting elements are arranged in the third accommodating space and is suitable for providing a plurality of first light beams to the reflective curved surface; a plurality of second light-emitting elements are arranged in The second accommodating space is suitable for providing a second light beam; and a beam splitting element is disposed on the transmission path of the second light beam, wherein the first light beams and the second light beams are transmitted out of the light outlet to form the Detecting light beams, and the reflective curved surface is suitable for reflecting the first light beams so that the transmission direction of the light exit port is all different. According to the light source device described in claim 12, the first light-emitting elements are located on the same plane and provide the first light beams in the same direction. An optical detection system, suitable for measuring an object to be tested, includes: a light source device, adapted to provide a detection beam to the object to be tested, including: a housing with a light outlet, a first accommodating space, and a A second accommodating space; a light guide structure arranged in the first accommodating space, having a reflective curved surface and a third accommodating space; a plurality of first light-emitting elements, arranged in the third accommodating space, suitable for Providing a plurality of first light beams to the reflective curved surface; a plurality of second light-emitting elements arranged in the second accommodating space, suitable for providing a second light beam; and a beam splitting element arranged on the transmission path of the second light beam An image capturing device, configured on the transmission path of the detection beam reflected by the object to be tested; and a processing device, electrically connected to the image capturing device, wherein the first beams and the second beam The light exit port is transmitted to form the detection beam, and the reflective curved surface is suitable for reflecting the first light beams so that the transmission directions of the light exit port are different. The optical inspection system according to item 14 of the scope of patent application, wherein the object to be tested has a hole structure, and the hole structure has a bottom area and one side In the wall area, the first light beams are transmitted to the side wall area, and the second light beams are transmitted to the bottom area.

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