Light source device and image capturing apparatus

Abstract

The utility model relates to a light source device and image shooting equipment. The light source device comprises a light source, a dodging part and an optical lens. The light source is used for emitting a first light beam, the dodging piece is arranged on a light path of the first light beam and provided with a first end face and a second end face, the end face of the first end face is opposite to a light-emitting face of the light source, and the first light beam enters the dodging piece through the first end face and is emitted through the second end face to form a second light beam. The optical lens is arranged on a light path of the second light beam and is used for reflecting the second light beam to a measured object. According to the light source device, the light intensity of the light irradiated to the measured object is higher, and the light spot brightness distribution is more uniform.

Description

Technical Field

[0001] The present application relates to the field of visual detection technology, and in particular to a light source device and an image capturing device. Background Art

[0002] The machine vision system uses machines to replace human eyes to make various measurements and judgments. It is an important branch of computer science. It integrates technologies in optics, mechanics, electronics, computer hardware and software, and involves multiple fields such as computers, image processing, pattern recognition, artificial intelligence, signal processing, optomechanical integration, etc.

[0003] The principle of the machine vision system is that a point light source is projected onto the object to be tested, and the object to be tested reflects and scatters the light beam, forming an image on the CCD. With the continuous innovation of chip technology and chip packaging technology, the chip area and packaging area are developing towards smaller, lighter, and thinner, and the difficulty of chip appearance inspection is also increasing. The light intensity and brightness of the point light source projected onto the object to be tested by the existing machine vision system are difficult to meet the requirements of detecting smaller defects on the chip, requiring the light intensity of the light irradiated to the inspection object to be higher and the brightness to be more uniform. Utility Model Content

[0004] Embodiments of the present application provide a light source device and an image capturing device.

[0005] In a first aspect, an embodiment of the present application provides a light source device, including a light source, a light homogenizer, and an optical lens. The light source is used to emit a first light beam, the light homogenizer is arranged on the light path of the first light beam, the light homogenizer has a first end face and a second end face, the area of ​​the first end face is smaller than the area of ​​the second end face, the end face of the first end face is opposite to the light emitting surface of the light source, the first light beam enters the light homogenizer through the first end face, and is emitted through the second end face to become a second light beam. The optical lens is arranged on the light path of the second light beam, and the optical lens is used to reflect the second light beam to the object to be measured.

[0006] In some optional embodiments, the light source has a light emitting surface, the light emitting surface and the first end surface are relatively spaced apart, and the ratio of the area of ​​the first end surface to the area of ​​the light emitting surface is greater than or equal to 0.9 and less than or equal to 1.2.

[0007] In some optional embodiments, the distance between the light emitting surface of the light source and the first end surface is less than or equal to 0.2 mm; and / or the angle of the first light beam received by the first end surface is greater than or equal to 120 degrees.

[0008] In some optional embodiments, the light homogenizer is a tapered light guide rod, and the taper of the tapered light guide rod is greater than or equal to 3 and less than or equal to 4.5.

[0009] In some optional embodiments, the tapered light guide rod includes any one of the following structures: a circular tapered light guide rod, a square tapered light guide rod, a pentagonal tapered light guide rod, and a hexagonal tapered light guide rod.

[0010] In some optional embodiments, a divergence angle of the second light beam emitted through the second end surface is less than or equal to 50 degrees.

[0011] In some optional embodiments, the distance between the first end surface and the second end surface is greater than or equal to 15 mm.

[0012] In some optional embodiments, the light source includes a light emitting diode chip, or the light source includes a laser chip and a wavelength conversion element, the laser chip is used to emit a laser beam, and the wavelength conversion element is used to convert the laser beam into a converted light with a different wavelength range.

[0013] In some optional embodiments, the optical lens is a transflective lens, which is arranged between the object to be measured and the image sensor and is located on the optical path of the third light beam emitted by the object to be measured. After the second light beam is reflected by the optical lens to the object to be measured, it is reflected by the object to be measured to form a third light beam; the optical lens is also used to transmit the third light beam.

[0014] In some optional embodiments, the reflectivity of the optical lens is 50%, and the transmittance of the optical lens is 50%.

[0015] In a second aspect, an embodiment of the present application further provides an image capture device, which includes a light source device of any one of the above items and an image sensor, wherein the image sensor is disposed on one side of the optical lens, and the image sensor is used to obtain a third light beam emitted from the object to be measured.

[0016] In some optional embodiments, the light homogenizer has an optical axis, and the light path from the light source to the optical lens propagates along the optical axis, and the optical axis is perpendicular to the light path of the third light beam to the image sensor.

[0017] In some alternative embodiments, the image sensor includes a charge coupled device image sensor or a complementary metal oxide semiconductor image sensor.

[0018] Compared with the prior art, when the light source device provided in the embodiment of the present application is used, the light source emits a first light beam, which enters the light homogenizer through the first end face, and after multiple reflections in the light homogenizer, it is emitted from the second end face to become a second light beam. The optical lens collects the second light beam and reflects it onto the object to be measured. The area of ​​the first end face of the light homogenizer is smaller than the area of ​​the second end face. According to the law of conservation of optical expansion, during the propagation of light, the expansion of the light beam remains unchanged in the propagation direction, then the divergence angle of the second light beam emitted from the second end face is smaller than the divergence angle of the first light beam received by the first end face. After being homogenized by the light homogenizer, the first light beam becomes a second light beam with a smaller divergence angle and a larger light spot, thereby improving the uniformity of the light intensity and brightness of the light irradiated on the object to be measured. Therefore, the light intensity of the light irradiated to the object to be measured by the light source device provided in the embodiment of the present application is higher, and the brightness distribution of the light spot is more uniform, thereby improving the applicability of the machine vision inspection system, and being able to detect smaller defects of the object to be measured. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solution of the present application, the drawings required for use in the implementation manner will be briefly introduced below. Obviously, the drawings described below are only some implementation manners of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0020] Figure 1 It is a simplified structural diagram of an image acquisition device provided in one embodiment of the present application.

[0021] Figure 2 yes Figure 1 The diagram is a simplified schematic diagram of a portion of the structure of a light source device of an image acquisition device.

[0022] Explanation of reference numerals: 100, light source device; 10, light source; 12, light emitting surface; 20, light source module; 30, light homogenizer; 32, first end surface; 34, second end surface; 36, tapered light guide rod; 50, optical lens; 200, object to be measured; 300, image acquisition device; 70, image sensor. DETAILED DESCRIPTION

[0023] In order to enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without making creative work are within the scope of protection of the present application.

[0024] If certain words are used in the specification and claims to refer to specific components, those skilled in the art should understand that hardware manufacturers may use different terms to refer to the same component. The specification and claims do not use differences in names as a way to distinguish components, but use differences in components' functions as the criteria for distinction. For example, "including" mentioned throughout the specification and claims is an open term, so it should be interpreted as "including but not limited to"; "substantially" means that those skilled in the art can solve technical problems within a certain error range and basically achieve technical effects.

[0025] See also Figure 1 An embodiment of the present application provides an image acquisition device 300, which can be applied to a machine vision inspection system, and is used to capture an electronic image of an object 200 to be inspected, and then send it to an image processor for analysis by the image processor.

[0026] The machine vision inspection system is used to replace the human eye to make measurements and judgments. This specification does not limit the specific structure of the machine vision inspection system. As an example, the machine vision inspection system may include the above-mentioned image acquisition device 300, image processor, monitor, communication / input and output unit, etc. The machine vision inspection system uses the image acquisition device 300 to convert the measured object 200 into an image signal, which is transmitted to a dedicated image processor, and converted into a digital signal according to pixel distribution, brightness, color and other information. The image processor performs various operations on these signals to extract the characteristics of the target, such as area, quantity, position, length, and then outputs the results according to the preset tolerance and other conditions, including size, angle, number, qualified / unqualified, presence / absence, etc., to realize the automatic recognition function.

[0027] The object 200 to be measured is usually an industrial product. This specification does not limit the specific type of the object 200 to be measured. For example, the object 200 to be measured may be a chip or a semiconductor product.

[0028] In this embodiment, the image capture device 300 may include a light source device 100 and an image sensor 70. The light source device 100 may include a light source 10, a light homogenizer 30, and an optical lens 50. The light source 10 is used to emit a first light beam A, and the light homogenizer 30 is arranged on the optical path of the first light beam A. The light homogenizer 30 has a first end face 32 and a second end face 34 opposite to each other, and the first end face 32 and the second end face 34 are both planes, and the area of ​​the first end face 32 is smaller than the area of ​​the second end face 34. Among them, the first end face 32 is opposite to the light emitting surface 12 of the light source 10, and the first light beam A enters the light homogenizer 30 through the first end face 32, and after multiple reflections inside the light homogenizer 30, it is emitted through the second end face 34 to become a second light beam B. The optical lens 50 is arranged on the optical path of the second light beam B, and the optical lens 50 is used to reflect the second light beam B to the object to be measured 200. The image sensor 70 is arranged on one side of the optical lens 50, and the image sensor 70 is used to obtain the third light beam C emitted from the object to be measured 200.

[0029] When in use, the light source 10 emits a first light beam A, which enters the light homogenizer 30 through the first end face 32, and after multiple reflections in the light homogenizer 30, it is emitted from the second end face 34 to become a second light beam B. The optical lens 50 collects the second light beam B and reflects it onto the object 200 to be measured. The object 200 to be measured reflects and scatters the light beam irradiated thereon, and the image sensor 70 collects the third light beam C reflected and scattered by the object 200 to be measured again and forms an image. The area of ​​the first end face 32 of the light homogenizer 30 is smaller than the area of ​​the second end face 34. According to the law of conservation of optical extension, during the propagation of light, the extension of the light beam remains unchanged in the propagation direction, so the divergence angle of the second light beam B emitted from the second end face 34 is smaller than the divergence angle of the first light beam A received by the first end face 32. After being homogenized by the light homogenizer 30, the first light beam A becomes a second light beam B with a smaller divergence angle and a larger light spot emitted from the second end face 34. The brightness distribution of the light spot of the second light beam B is uniform, so that the energy density and brightness of the light irradiated on the object to be measured 200 are larger. Therefore, the light intensity of the light irradiated by the light source device 100 provided in the embodiment of the present application to the object to be measured 200 is higher, and the brightness distribution of the light spot is more uniform, thereby improving the applicability of the machine vision inspection system and being able to detect smaller defects of the object to be measured 200.

[0030] Please also see Figure 1 and Figure 2In this embodiment, the light source 10 is used to emit a first light beam A. The light source 10 has a light emitting surface 12, and the first light beam A is emitted from the light emitting surface 12. The light source 10 is a Lambertian light source, and the first light beam A is Lambertian light. The beam angle of the first light beam A can reach 180°. The light emitting surface 12 and the first end surface 32 are arranged relatively spaced apart, and the first end surface 32 can receive the first light beam A emitted from the light emitting surface 12. The first end surface 32 is a plane, which is used for light transmission. In order to enable the first end surface 32 to receive more first light beams A, the area of ​​the first end surface 32 can be equal to the area of ​​the light emitting surface 12, or the area of ​​the first end surface 32 can be slightly larger than or smaller than the area of ​​the light emitting surface 12. In this embodiment, the ratio of the area of ​​the first end surface 32 to the area of ​​the light emitting surface 12 is greater than or equal to 0.9 and less than or equal to 1.2. For example, the ratio of the area of ​​the first end surface 32 to the area of ​​the light emitting surface 12 can be 0.9, 1, 1.1, 1.2, etc.

[0031] In some embodiments, in order to further improve the receiving rate of the first end surface 32 for the first light beam A, the distance between the first end surface 32 and the light emitting surface 12 can be adjusted. The first end surface 32 and the light emitting surface 12 can be parallel to each other. In this embodiment, the distance between the light emitting surface 12 and the first end surface 32 is less than or equal to 0.2 mm. For example, the distance between the light emitting surface 12 and the first end surface 32 can be 0.2 mm, 0.1 mm, etc. In this embodiment, the angle ɑ of the first light beam A received by the first end surface 32 is greater than or equal to 120 degrees, which improves the utilization rate of the first light beam A emitted by the light source 10, thereby improving the light intensity of the second light beam B. The angle ɑ of the first light beam A received by the first end surface 32 can be 120°, 130°, 140°, etc. In other embodiments, the angle ɑ of the first light beam A received by the first end surface 32 is greater than or equal to 120 degrees.

[0032] In other embodiments, in order to improve the light beam transmittance of the first end surface 32 and the second end surface 34 , the surfaces of the first end surface 32 and the second end surface 34 may be covered with an anti-reflection film.

[0033] This specification does not limit the specific type of the light source 10. The light source 10 may include a light emitting diode chip, or the light source 10 may include a laser chip and a wavelength conversion element. The laser chip is used to emit a laser beam, and the wavelength conversion element is used to convert the laser beam into a converted light with a different wavelength range. Among them, the "wavelength conversion element" may include a fluorescent substance, such as a fluorescent color wheel. As an example, the light source 10 may include a light emitting diode chip, and the number of light emitting diode chips may be set to one or more. In the present embodiment, the light source 10 includes a light emitting diode chip assembly, which is a combination of multiple light emitting diode chips, wherein the wavelengths of the multiple light emitting diode chips may be the same or different.

[0034] In this embodiment, the light homogenizer 30 is used to homogenize the first light beam A to make it a second light beam B with a more uniform distribution of light spot brightness. The light homogenizer 30 can be a light homogenizer rod, which is a rod-shaped lens made of an optical material with high light transmittance (such as fused quartz glass). When the uneven first light beam A enters the light homogenizer 30 through the first end face 32, multiple reflections occur inside the light homogenizer 30, and each reflection will generate an equivalent virtual light source on the rear extension line of the reflected light beam, and the second light beam B emitted from the second end face 34 can be understood as the superposition of light beams generated by virtual light sources at many different positions, thereby generating a second light beam B with higher light uniformity.

[0035] This specification does not limit the structural shape of the light homogenizer 30. In this embodiment, the light homogenizer 30 is a tapered light guide rod 36, and the first end face 32 and the second end face 34 are planes, both of which are used for light transmission. The area of ​​the first end face 32 is smaller than the area of ​​the second end face 34, and the first end face 32 and the second end face 34 can be parallel to each other. The small end (first end face 32) of the tapered light guide rod 36 receives the first light beam A, and emits it from the large end (second end face 34) as the second light beam B. Since the optical extension amount remains unchanged, the first light beam A emitted from the light source 10 has a small luminous area and a large emission angle. After being homogenized by the tapered light guide rod 36, the light spot of the second light beam B emitted from the second end face 34 becomes larger, the divergence angle of the emission becomes smaller, and the brightness distribution of the light spot becomes more uniform.

[0036] The light source device 100 provided in the embodiment of the present application uses a tapered light guide rod 36 to realize multiple reflections of the light beam. Each reflection will generate an equivalent virtual light source on the rear extension line of the reflected light beam. Therefore, the light beam (second light beam B) emitted by the tapered light guide rod 36 can be considered as the superposition of light beams generated by light sources at many different positions, thereby improving the uniformity of light. In some embodiments, the taper of the tapered light guide rod 36 can be set so that the light beam is totally reflected in the tapered light guide rod 36. For example, the incident angle of the light beam on the inner wall of the tapered light guide rod 36 is greater than the critical angle from the tapered light guide rod 36 to the air, so total reflection occurs, thereby reducing light loss. The taper of the tapered light guide rod 36 can be greater than or equal to 3 and less than or equal to 4.5. For example, the taper of the tapered light guide rod 36 is 3, 4, 4.5, etc. In other embodiments, a reflective film, such as a reflection-enhancing film or a total reflection film, may be provided on the inner wall of the tapered light guide rod 36 , so that the light beam undergoes multiple total reflections inside the tapered light guide rod 36 and then emerges from the second end surface 34 .

[0037] The taper adjustment of the tapered light guide rod 36 can change the light output angle of the second light beam B emitted from the second end face 34. The taper setting of the tapered light guide rod 36 makes the divergence angle b of the second light beam B emitted through the second end face 34 less than or equal to 50°. For example, the divergence angle b of the second light beam B can be 30°, 40°, 50°, etc. In the present embodiment, the divergence angle b of the second light beam B is 30°, which improves the receiving rate of the optical lens 50 for the second light beam B and improves the utilization rate of the first light beam A emitted by the light source 10. In the present embodiment, the light homogenizer 30 reduces the divergence angle of the light beam. Considering the case where the divergence angle b of the second light beam B is 30°, the optical lens 50 can collect almost all of the second light beam B, reducing light loss, thereby improving light intensity.

[0038] This specification does not limit the specific shape of the tapered light guide rod 36. The cross section of the tapered light guide rod 36 can be circular or polygonal (for example, pentagonal or hexagonal). For example, the tapered light guide rod 36 can include any one of the following structures: a tapered light guide rod, a square tapered light guide rod, a pentagonal tapered light guide rod, and a hexagonal tapered light guide rod. In this embodiment, the tapered light guide rod 36 is a tapered light guide rod. The conical surface of the tapered light guide rod is a polished surface. After the first light beam A enters the tapered light guide rod 36, it can be fully reflected multiple times on the inner wall of the conical surface. This specification does not limit the specific length of the tapered light guide rod 36. In order to improve the uniform light effect of the tapered light guide rod 36, in this embodiment, the length of the tapered light guide rod 36 is greater than or equal to 15 mm, that is, the distance between the first end face 32 and the second end face 34 is greater than or equal to 15 mm. For example, the distance between the first end face 32 and the second end face 34 can be 15 mm, 16 mm, 18 mm, etc. As an example, the length of the tapered light guide rod 36 is less than or equal to 100 mm, for example, the length of the tapered light guide rod 36 is 50 mm, 60 mm, 70 mm, 80 mm, 90 mm, 100 mm. The longer the length of the tapered light guide rod 36 is, the more times the first light beam A can be totally reflected, so that the second light beam B emitted from the second end surface 34 can obtain a more uniform light spot.

[0039] After the first light beam A is homogenized by the tapered light guide rod 36 , the light spot brightness distribution of the second light beam B emitted from the second end surface 34 is uniform, and when it is transmitted to the object 200 to be measured through the optical lens 50 , a relatively uniform light spot can be formed.

[0040] The light source 10 and the light homogenizer 30 together form a light source module 20. The light source module 20 has a high light intensity and a highly uniform light spot brightness distribution. This specification does not limit the specific application of the light source module 20. The light source module 20 can not only be used in machine vision inspection systems, for example, the light source module 20 can also be used in stage lights, car lights, flashlights, searchlights and other equipment.

[0041] In this embodiment, the optical lens 50 is arranged at the end of the light homogenizer 30 away from the light source 10, that is, at the second end face 34 of the light homogenizer 30, and the optical lens 50 is used to reflect the second light beam B emitted from the second end face 34 to the object to be measured 200. The light homogenizer 30 has an optical axis P, which is the central axis of the tapered light guide rod 36, and the light path from the light source 10 to the optical lens 50 propagates along the optical axis P. The optical lens 50 is tilted relative to the optical axis P to change the propagation angle of the second light beam B and guide the second light beam B to the object to be measured 200. The optical lens 50 images the light spot of the second end face 34 onto the object to be measured 200, so that the brightness distribution of the light spot of the light beam projected onto the object to be measured 200 is more uniform.

[0042] In this embodiment, the optical lens 50 is a transflective lens. The optical lens 50 is disposed between the object to be measured 200 and the image sensor 70 and is located on the optical path of the third light beam C. After the second light beam B is reflected by the optical lens 50 to the object to be measured 200, it is reflected by the object to be measured 200 to form the third light beam C. The optical lens 50 is also used to transmit the third light beam C. The image sensor 70 is located on the optical path after the third light beam C transmits the optical lens 50. The optical lens 50 reflects the second light beam B emitted from the second end surface 34 to the object to be measured 200, and then the object to be measured 200 reflects and scatters the second light beam B to form the third light beam C. The optical lens 50 transmits the third light beam C, and part of the third light beam C passes through the optical lens 50 and is imaged on the image sensor 70. In some embodiments, the third light beam C may also include a self-luminous light beam of the object to be measured 200.

[0043] This specification does not limit the specific type of the optical lens 50. In this embodiment, the optical lens 50 is a telecentric lens. The telecentric lens can focus and magnify the light beam so that the details of distant objects or tiny objects can be clearly seen. The telecentric lens is well used in machine vision detection systems. When measuring the area, the telecentric lens can obtain the same measurement result without considering the change of object distance or position. In this embodiment, the reflectivity of the optical lens 50 is 50%, and the transmittance of the optical lens is 50%. The optical lens 50 can both reflect the second light beam B to the object 200 to be measured, and can also transmit the third light beam C emitted by the object 200 to the image sensor 70.

[0044] In this embodiment, the image sensor 70 is arranged on the side of the optical lens 50 away from the object 200 to be measured, and the image sensor 70 is used to obtain the light beam reflected or scattered by the object 200 (that is, the third light beam C), so as to obtain the image information of the object 200 to achieve visual detection. In this embodiment, the optical path of part of the third light beam C propagating to the image sensor 70 is perpendicular to the optical axis P of the light homogenizer 50. This position setting improves the compactness of the structure of the image acquisition device 300 and reduces the occupied space of the image acquisition device 300. This specification does not limit the specific type of the image display 70, and the image display 70 may include a charge coupled device image sensor or a complementary metal oxide semiconductor image sensor. In this embodiment, the image display 70 is a charge coupled device image sensor (Charge Coupled Device, CCD). The CCD image sensor is made of a semiconductor material with high sensitivity, which can convert the light beam into an electric charge, and convert it into a digital signal through an analog-to-digital converter chip. After the digital signal is compressed, it is stored in the flash memory or built-in hard disk card inside the camera, and the data can be easily transmitted to the computer.

[0045] When the image acquisition device 300 provided by the embodiment of the present application is used, the light source 10 emits a first light beam A, the first light beam A enters the light homogenizer 30 through the first end face 32, and after multiple reflections in the light homogenizer 30, it is emitted from the second end face 34 to become a second light beam B. The optical lens 50 collects the second light beam B and reflects it to the object 200 to be measured. The object 200 to be measured reflects and scatters the light beam irradiated thereon, and the image sensor 70 collects the third light beam C reflected and scattered by the object 200 to be measured again and forms an image. The area of ​​the first end face 32 of the light homogenizer 30 is smaller than the area of ​​the second end face 34. According to the law of conservation of optical etendue, during the propagation of light, the expansion of the light beam remains unchanged in the propagation direction, and the divergence angle of the second light beam B emitted from the second end face 34 is smaller than the divergence angle of the first light beam A received by the first end face 32. After being homogenized by the light homogenizer 30, the first light beam A becomes a second light beam B with a smaller divergence angle and a larger light spot, thereby improving the uniformity of the light intensity and brightness of the light irradiated on the object 200 to be measured. Therefore, the light intensity of the light irradiated to the object 200 by the light source device 100 provided in the embodiment of the present application is higher, and the brightness distribution of the light spot is more uniform, thereby improving the applicability of the machine vision inspection system and being able to detect smaller defects of the object 200 under inspection.

[0046] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0047] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A light source device, characterized in that: The light source device comprises: A light source, configured to emit a first light beam; a light homogenizer, arranged on the optical path of the first light beam, the light homogenizer having a first end face and a second end face opposite to each other, the area of ​​the first end face is smaller than the area of ​​the second end face, the first end face is opposite to the light emitting surface of the light source, the first light beam enters the light homogenizer through the first end face, and after multiple reflections inside the light homogenizer, is emitted through the second end face to become a second light beam; and An optical lens is arranged on the optical path of the second light beam, and is used to reflect the second light beam to the object to be measured.

2. The light source device according to claim 1, wherein: The light source has a light emitting surface, the light emitting surface and the first end surface are arranged relatively spaced apart, and the ratio of the area of ​​the first end surface to the area of ​​the light emitting surface is greater than or equal to 0.9 and less than or equal to 1.

2.

3. The light source device according to claim 1, wherein: The distance between the light emitting surface of the light source and the first end surface is less than or equal to 0.2 mm; and / or, The angle of the first light beam received by the first end surface is greater than or equal to 120 degrees.

4. The light source device according to claim 1, wherein: The light homogenizer is a tapered light guide rod, and the taper of the tapered light guide rod is greater than or equal to 3 and less than or equal to 4.

5.

5. The light source device according to claim 4, characterized in that: The tapered light guide rod includes any one of the following structures: a circular tapered light guide rod, a square tapered light guide rod, a pentagonal tapered light guide rod, and a hexagonal tapered light guide rod.

6. The light source device according to claim 4, characterized in that: A divergence angle of the second light beam emitted through the second end surface is less than or equal to 50 degrees.

7. The light source device according to claim 1, wherein: A distance between the first end surface and the second end surface is greater than or equal to 15 mm.

8. The light source device according to claim 1, wherein: The light source includes a light emitting diode chip, or The light source comprises a laser chip and a wavelength conversion element. The laser chip is used to emit a laser beam, and the wavelength conversion element is used to convert the laser beam into a converted light with a different wavelength range.

9. The light source device according to any one of claims 1 to 8, characterized in that: The optical lens is a transflective lens, which is arranged between the object to be measured and the image sensor and is located on the optical path of the third light beam emitted by the object to be measured. After the second light beam is reflected by the optical lens to the object to be measured, it is reflected by the object to be measured to form the third light beam; the optical lens is also used to transmit the third light beam.

10. The light source device according to claim 9, characterized in that: The reflectivity of the optical lens is 50%, and the transmittance of the optical lens is 50%.

11. An image acquisition device, characterized in that: The image acquisition device comprises: The light source device according to any one of claims 1 to 10; and An image sensor is arranged on one side of the optical lens, and is used to obtain a third light beam emitted from the object to be measured.

12. The image pickup device according to claim 11, characterized in that The light homogenizer has an optical axis, and the light path from the light source to the optical lens propagates along the optical axis, and the optical axis is perpendicular to the light path of the third light beam propagating to the image sensor.

13. The image pickup device according to claim 11, characterized in that The image sensor includes a charge coupled device image sensor or a complementary metal oxide semiconductor image sensor.

Images