Optical detection system

Abstract

The embodiment of the invention provides an optical detection system which is used for improving the accuracy of obtaining illumination light intensity in an illumination light beam. The method comprises the following steps: an illumination optical system used for emitting an illumination light beam and irradiating the illumination light beam to a detection object; the focusing optical system comprises a detection light emitting device and an adjusting device, the detection light emitting device is used for emitting a focus detection light beam to a detection object so that the distance between the detection object and the imaging device can be obtained through the focus detection light beam, and the adjusting device is used for adjusting the distance so that the detection object can be located at the focus of the imaging device; before irradiating a detected object, the focus detection light beam and the illumination light beam are coupled through a coupler; the illumination light intensity detection device is used for detecting the energy of the coupled illumination light beams; and the imaging device is used for imaging the focused detection object to obtain an image of the detection object, and the image of the detection object is used for feature detection.

Description

Technical Field

[0001] The present invention relates to the field of optical detection technology, and in particular to an optical detection system. Background Art

[0002] In the semiconductor wafer inspection system, there are various lighting optical systems such as illumination light sources and autofocus light sources. The illumination light source is used to provide an illumination light beam for illuminating the inspection object, and the autofocus light source is used to provide a focusing light beam for automatic ranging. The brightness of the illumination light beam irradiating the surface of the inspection object is a key indicator and needs to be monitored in real time. When monitoring the brightness of the illumination light source in real time, interference from the autofocus light source also needs to be avoided.

[0003] The prior art obtains the brightness of the illumination beam by calculating the grayscale of the image finally obtained. The grayscale of the image is affected not only by the illumination intensity but also by the camera parameters and the illumination wavelength. Therefore, the method of calculating the intensity of the illumination beam by using the grayscale of the image has poor accuracy. Summary of the invention

[0004] The embodiment of the present invention provides an optical detection system, which can directly measure the light intensity of a coupled illumination light beam through an illumination light intensity detection device, thereby improving the accuracy of obtaining the illumination light intensity in the illumination light beam.

[0005] The embodiment of the present application provides an optical detection system, including: an illumination optical system, a focusing optical system, a coupler, an illumination light intensity detection device, and an imaging device, wherein:

[0006] The illumination optical system is used to emit an illumination light beam and irradiate the illumination light beam to the detection object;

[0007] The focusing optical system comprises a detection light emitting device and an adjusting device, wherein the detection light emitting device is used to emit a focus detection beam to the detection object so as to obtain the distance between the detection object and the imaging device through the focus detection beam, and the adjusting device is used to adjust the distance so that the detection object is located at the focus of the imaging device, wherein the focus detection beam and the illumination beam are coupled through the coupler before being irradiated to the detection object;

[0008] The illumination light intensity detection device is used to detect the energy of the illumination light beam after coupling;

[0009] The imaging device is used to image the focused detection object to obtain an image of the detection object, wherein the image of the detection object is used for feature detection.

[0010] As a possible embodiment, the illumination light intensity detection device and the illumination optical system are coaxially arranged along the direction of the illumination light beam.

[0011] As a possible embodiment, the illumination light intensity detection device includes a first optical component, a photodetector and a signal processing unit, wherein:

[0012] The first optical component is used to receive the illumination beam from the coupled beam and isolate the focus detection beam;

[0013] The photoelectric detector is used to convert the optical signal of the illumination light beam after passing through the first optical component into an electrical signal;

[0014] The signal processing unit is used to measure the energy of the illumination light beam based on the electrical signal.

[0015] As a possible embodiment, the illumination light intensity detection device further includes a second optical component, wherein:

[0016] The second optical component is arranged on the optical path between the first optical component and the photodetector, and is used to focus the illumination light beam passing through the first optical component onto the photodetector.

[0017] As a possible embodiment, the illumination light intensity detection device further includes a third optical component, wherein:

[0018] The third optical component is used to attenuate the energy of the illumination light beam passing through the second optical component to an energy detection range of the photodetector.

[0019] As a possible embodiment, the first optical component includes at least one of a bandpass filter, a high-pass filter and a low-pass filter, the second optical component includes a lens group, and the third optical component includes an optical attenuation plate.

[0020] As a possible embodiment, the second optical component is perpendicular to the illumination light beam after passing through the first optical component.

[0021] As a possible embodiment, at least one component among the first optical component, the third optical component and the photodetector is tilted relative to the second optical component.

[0022] As a possible embodiment, the coupler includes a dichroic mirror, which is used to transmit the focusing beam to the detection object, transmit the beam of the first energy ratio in the illumination beam to the illumination light intensity detection device, and reflect the beam of the second energy ratio in the illumination beam to the detection object, wherein the first energy ratio is smaller than the second energy ratio.

[0023] As a possible embodiment, the illumination optical system includes: an illumination light source, and at least one of a beam shaping device, an optical modulation device and an illumination tube lens sequentially arranged along a propagation direction of the illumination light beam;

[0024] The illumination light source is used to emit an initial light beam;

[0025] The beam shaping device adjusts the divergence angle of the initial light beam so that the initial light beam has a preset aperture angle and a preset field angle;

[0026] The optical modulation device is used to select an illumination light beam of a preset wavelength band from the initial light beam after the divergence angle is adjusted;

[0027] The illumination tube lens is used to adjust the propagation direction of the illumination light beam and make the adjusted illumination light beam incident on the coupler.

[0028] As a possible embodiment, the beam shaping device includes at least one of a lens group, a homogenizing tube and frosted glass, the optical modulation device includes at least one of a filter, an attenuation plate, a polarizer and an aperture, and the illumination tube lens includes a lens group.

[0029] As a possible embodiment, the imaging device is arranged on the optical path between the coupler and the detection object through a beam splitter along the direction of the coupled illumination light beam.

[0030] As a possible embodiment, the imaging device includes an objective lens and an imaging assembly, wherein the objective lens is arranged on the optical path of the illumination beam transmitted by the beam splitter, and is used to transmit the illumination beam and the focus detection beam transmitted by the beam splitter to the detection object, and receive the illumination beam and the focus detection beam reflected by the detection object;

[0031] The beam splitter is used to transmit the focus detection beam reflected by the detection object to the detection light emitting device, and reflect the illumination beam reflected by the detection object to the imaging component;

[0032] The imaging component is arranged on the optical path of the illumination light beam reflected by the beam splitter, and is used to image the detection object according to the illumination light beam reflected by the detection object.

[0033] It can be seen from the above technical solutions that the embodiments of the present invention have the following advantages:

[0034] In the embodiment of the present application, the optical detection system includes: an illumination optical system, a focusing optical system, a coupler, an illumination light intensity detection device and an imaging device, wherein the illumination optical system is used to emit an illumination light beam and irradiate the illumination light beam to the detection object; the focusing optical system includes a detection light emitting device and an adjustment device, wherein the detection light emitting device is used to emit a focusing light beam to the detection object so as to obtain the distance between the detection object and the imaging device through the focusing light beam, and the adjustment device is used to adjust the distance so that the detection object is located at the focus of the imaging device, wherein the focusing light beam and the illumination light beam are coupled through the coupler before being irradiated to the detection object; the illumination light intensity detection device is used to detect the energy of the coupled illumination light beam; the imaging device is used to image the detection object after focusing so as to obtain an image of the detection object, wherein the image of the detection object is used for feature detection.

[0035] Because the illumination light intensity detection device in the embodiment of the present application can directly measure the energy of the illumination light beam after coupling, the accuracy of obtaining the energy of the illumination light beam in the optical detection system is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 This is a schematic diagram of an embodiment of an optical detection system in an embodiment of the present application;

[0037] Figure 2 This is another schematic diagram of an optical detection system in an embodiment of the present application;

[0038] Figure 3 Schematic diagram of the transmittance of the light film to the illumination light beam and the focus detection light beam in the embodiment of the present application;

[0039] Figure 4 This is a schematic diagram of the internal structure of the light intensity detection device in the embodiment of the present application;

[0040] Figure 5 Schematic diagram of the internal structure of the illumination optical system 10 and the internal structure of the imaging device 50 in the optical detection system in the embodiment of the present application. DETAILED DESCRIPTION

[0041] The embodiment of the present invention provides an optical detection system, which can directly measure the energy (light intensity) of the coupled illumination light beam through an illumination light intensity detection device, thereby improving the accuracy of obtaining the illumination energy in the illumination light beam.

[0042] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0043] The terms "first", "second", "third", "fourth", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments described herein can be implemented in an order other than that illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0044] For ease of understanding, the optical detection system in the embodiment of the present application is described below. Figure 1 , an embodiment of the optical detection system in the embodiment of the present application includes:

[0045] Illumination optical system 10, focusing optical system 20, coupler 30, illumination light intensity detection device 40 and imaging device 50, wherein:

[0046] The illumination optical detection system 10 is used to emit an illumination beam and illuminate the illumination beam to the detection object. The detection object in the embodiment of the present application includes a wafer, a chip, a mask, a glass screen, etc., and there is no specific limitation on the detection object here.

[0047] The focusing optical system 20 includes a detection light emitting device 201 and an adjusting device 202, wherein the detection light emitting device 201 is used to emit a focusing beam to the detection object so as to obtain the distance between the detection object and the imaging device through the focusing beam, and the adjusting device 202 is used to adjust the distance between the detection object and the imaging device so that the detection object is located at the focus of the imaging device, wherein the focusing beam and the illumination beam are coupled through the coupler 30 before being irradiated to the detection object.

[0048] Specifically, the illumination beam and the focusing beam in the embodiment of the present application are beams of different bands. For example, when the illumination beam is a beam within the band range of λ1 to λ2, the focusing beam is a beam within the band range of λ3 to λ4. No specific limitation is made on the wavelengths of the illumination beam and the focusing beam.

[0049] Furthermore, the coupler in the embodiment of the present application can be a beam splitter, a dichroic mirror or a reflector, etc., as long as it can couple the illumination beam and the focusing beam, and there is no specific limitation on the type of the coupler.

[0050] The illumination light intensity detection device 40 is used to detect the energy (light intensity) of the illumination light beam after coupling;

[0051] The imaging device 50 is used to image the focused inspection object to obtain an image of the inspection object, wherein the image of the inspection object is used for feature detection, such as detecting defects in the image of the inspection object through a processor.

[0052] The embodiment of the present application is different from the method of measuring the light intensity of the illumination light beam by image grayscale in the prior art. By setting up an illumination light intensity detection device 40, the energy of the illumination light beam after coupling is directly detected, thereby improving the accuracy of obtaining the energy (light intensity) of the illumination light beam.

[0053] based on Figure 1 The optical detection system in the embodiment of the present application is described below. Figure 2 Another embodiment of the optical detection system after the embodiment of the present application includes:

[0054] Illumination optical system 10, focusing optical system 20, coupler 30, illumination light intensity detection device 40 and imaging device 50, wherein:

[0055] The illumination optical detection system 10 is used to emit an illumination light beam along a first direction and illuminate the illumination light beam to the detection object. The detection object in the embodiment of the present application includes a wafer, a chip, a mask, a glass screen, etc., and there is no specific limitation on the detection object here.

[0056] The focusing optical system 20 includes a detection light emitting device 201 and an adjusting device 202, wherein the detection light emitting device 201 is used to emit a focusing beam to the detection object along the second direction to obtain the distance between the detection object and the imaging device through the focusing beam, and the adjusting device 202 is used to adjust the distance between the detection object and the imaging device so that the detection object is located at the focus of the imaging device, wherein the focusing beam and the illumination beam are coupled through the coupler 30 before being irradiated to the detection object.

[0057] The illumination light intensity detection device 40 is used to detect the intensity of the illumination light beam after coupling;

[0058] The imaging device 50 is used to image the focused inspection object to obtain an image of the inspection object, wherein the image of the inspection object is used for feature detection, such as detecting defects in the image of the inspection object through a processor.

[0059] Furthermore, in order to reduce the volume of the optical detection system, the first direction and the second direction in the embodiment of the present application are perpendicular to each other, and the coupler 30 is a dichroic mirror, which is used to transmit the focusing beam to the detection object, transmit the beam of the first energy ratio in the illumination beam to the illumination light intensity detection device, and reflect the beam of the second energy ratio in the illumination beam to the detection object, wherein the first energy ratio is smaller than the second energy ratio, such as transmitting 5% of the beam to the illumination light intensity detection device, and reflecting 95% of the beam to the detection object.

[0060] In the embodiment of the present application, the illumination light intensity detection device 40 and the illumination optical system 10 are coaxially arranged along the direction of the illumination light beam, so as to measure the energy (light intensity) of the coupled illumination light beam. The coaxial arrangement of the light intensity detection device 40 and the illumination optical system 10 along the direction of the illumination light beam can not only improve the neatness of the light path arrangement, but also reduce the volume of the light path, so as to further reduce the space occupancy of the optical detection system.

[0061] Specifically, the light intensity detection device in the embodiment of the present application includes a first optical component 401, a photodetector 404 and a signal processing unit 405, wherein the first optical component 401 is coated with a light film, wherein the transmittance of the light film to the illumination beam band is greater than a first threshold, and the transmittance to the focus detection beam band is less than a second threshold, so as to receive the illumination beam from the coupled light beam and isolate the focus detection beam, and the first threshold is greater than the second threshold.

[0062] As a possible embodiment, the transmittance of the optical film in the embodiment of the present application to the illumination beam band is 1, while the transmittance to the focus beam band is 0, thereby achieving automatic isolation of the focus beam. Figure 3 A schematic diagram of the transmittance of the optical film to the illumination beam and the focusing beam is given.

[0063] As a possible embodiment, the first optical component in the embodiment of the present application includes a bandpass filter, a high-pass filter or a low-pass filter, so as to receive the illumination beam from the coupled light beam and isolate the focus detection beam.

[0064] Furthermore, because the illumination light beam after passing through the first optical component is weak, in order to enhance the signal of the illumination light beam, the illumination light intensity detection device 40 can also be provided with a second optical component 402 on the optical path between the first optical component 401 and the photodetector 404, so as to focus the illumination light beam after passing through the first optical component onto the photodetector 404.

[0065] As a possible embodiment, the second optical component 402 includes a single focusing lens or a combination of multiple lenses to focus the illumination light beam.

[0066] Furthermore, because the photodetector 404 (such as a photodiode) has its own response range to optical power, in order to improve the dynamic detection range of the photodetector to optical power, the embodiment of the present application may further provide a third optical component 403 in the light intensity detection device 40, wherein the third optical component 403 is used to attenuate the optical power of the illumination light beam to the optical power response range of the photodetector 404, so as to improve the dynamic detection range of the photodetector to the optical power of the illumination light beam. For ease of understanding, Figure 4 A schematic diagram of the internal structure of the light intensity detection device is given.

[0067] As a possible embodiment, the third optical component 403 in the embodiment of the present application includes an optical attenuation plate.

[0068] In the light intensity detection device 40, because the second optical component 402 is perpendicular to the illumination light beam so as to focus the illumination light beam onto the photodetector, in order to avoid the first optical component 401, the third optical component 403 and the photodetector 404 from reflecting the illumination light beam, causing the reflected illumination light beam to return to the original illumination light path and affect the original illumination light path, in the embodiment of the present application, the first optical component 401, the third optical component 403 and / or the photodetector 404 are tilted relative to the second optical component 402.

[0069] In the embodiment of the present application, the internal components of the light intensity detection device 40 and the functions of each component are described in detail, wherein the first optical component 401 is used to receive the illumination light beam and isolate the focusing beam, thereby achieving the acquisition of the illumination light beam from the coupled light beam, thereby achieving automatic measurement of the light intensity of the illumination light beam by the photoelectric detector.

[0070] based on Figure 2The embodiment described above, the illumination optical system 10 and the imaging device 50 are described in detail below, because the illumination light beam emitted by the illumination optical detection system 10 needs to provide a light field of a preset size (that is, a light spot of a preset size) to the detection object before irradiating the detection object, and in order to achieve control of the light field size, the embodiment of the present application requires that the illumination light beam has a preset field angle before incident on the detection object, wherein the larger the field angle, the larger the light spot. Further, in order to improve the resolution of the image, the embodiment of the present application requires that the illumination light beam has a preset aperture angle before incident on the detection object, wherein the larger the aperture angle, the higher the resolution of the image by the imaging device, that is, the higher the recognition rate of the image details.

[0071] Therefore, the illumination light beam emitted by the illumination optical system 10 in the embodiment of the present application is required to have a preset aperture angle and a preset field of view angle. Therefore, the illumination optical detection system 10 in the embodiment of the present application includes an illumination light source 101, and at least one of a beam shaping device 102, an optical modulation device 103 and an illumination tube lens 104 arranged in sequence along the propagation direction of the illumination light beam.

[0072] The illumination light source 101 is used to emit an initial light beam along a first direction, and the beam shaping device 102 is used to adjust the divergence angle of the initial light beam so that the initial light beam has a preset aperture angle and a preset field angle.

[0073] As an optional embodiment, the beam shaping device 102 includes a lens group, or a lens group and at least one of a light averaging tube and frosted glass, so that the initial light beam after adjusting the divergence angle is more uniform, wherein the uniformity here refers to the fact that the light intensity in a preset light field irradiating the detection object is the same everywhere (that is, spatially uniform), and on the other hand, it also refers to the fact that the aperture angles of illumination light beams with different divergence angles in different directions are also the same (that is, the aperture angle is uniform).

[0074] Furthermore, the optical modulation device 103 is used to filter out an illumination beam of a preset band from the initial beam. Assuming that the initial beam emitted by the illumination light source 101 is a beam within the λ1-λ2 band, the optical modulation device can filter out a beam with a wavelength of λ0 from the above band.

[0075] As an optional embodiment, the optical modulation device 103 includes a filter, or a filter and at least one of an attenuation plate, a polarizer, an aperture and other elements to achieve modulation of optical parameters in the illumination light beam.

[0076] Furthermore, the illumination tube lens 104 is used to adjust the propagation direction of the illumination light beam in a preset wavelength band (such as λ0 wavelength), and make the illumination light beam after the adjustment be incident on the coupler (dichroic mirror).

[0077] As an optional embodiment, the illumination tube lens 104 includes a single lens or a combination of multiple lenses.

[0078] In addition, the imaging device 50 in the embodiment of the present application is arranged on the optical path between the coupler 30 and the detection object through a beam splitter along the direction of the coupled illumination light beam.

[0079] As an optional embodiment, the imaging device 50 in the embodiment of the present application includes an objective lens 501 and an imaging component 502, wherein the objective lens 501 is arranged on the optical path of the illumination light beam transmitted by the spectroscope, and is used to transmit the illumination light beam and the focusing light beam transmitted by the spectroscope to the detection object, and to receive the illumination light beam and the focusing light beam reflected by the detection object, wherein the illumination light beam reflected by the detection object is used to image the detection object, and the focusing light beam reflected by the detection object is returned to the detection light emitting device for measuring the focus of the objective lens.

[0080] The beam splitter is used to transmit the focus light beam reflected by the detection object to the detection light emitting device, and reflect the illumination light beam reflected by the detection object to the imaging component 502.

[0081] The imaging component 502 is disposed on the light beam of the illumination light beam reflected by the beam splitter, and is used to image the detection object according to the illumination light beam reflected by the detection object.

[0082] Specifically, the beam splitter in the embodiment of the present application can be coated to achieve partial transmission (such as 50% transmission) of the illumination beam and full transmission of the focusing beam.

[0083] For ease of understanding, Figure 5 A schematic diagram of the internal structure of the illumination optical system 10 and a schematic diagram of the internal structure of the imaging device 50 in the optical detection system are given.

[0084] In the embodiment of the present application, because the illumination optical system includes an illumination light source 101, and at least one of a beam shaping device 102, an optical modulation device 103 and an illumination tube lens 104 sequentially arranged along the propagation direction of the illumination light beam, the illumination light beam has a preset aperture angle and a preset field of view angle, thereby improving the recognition rate of the optical inspection system for defects of the inspection object.

[0085] The imaging device 50 is disposed on the optical path of the illumination light beam reflected by the beam splitter, and images the detection object according to the illumination light beam reflected by the detection object, thereby further improving the neatness of the optical path and reducing the volume of the optical detection system.

[0086] As described above, the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features thereof may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. An optical detection system, characterized in that: include: Illumination optical system, focusing optical system, coupler, illumination light intensity detection device and imaging device, wherein: The illumination optical system is used to emit an illumination light beam and irradiate the illumination light beam to the detection object; The focusing optical system comprises a detection light emitting device and an adjusting device, wherein the detection light emitting device is used to emit a focus detection beam to the detection object so as to obtain the distance between the detection object and the imaging device through the focus detection beam, and the adjusting device is used to adjust the distance so that the detection object is located at the focus of the imaging device, wherein the focus detection beam and the illumination beam are coupled through the coupler before being irradiated to the detection object; The illumination light intensity detection device is used to detect the energy of the illumination light beam after coupling; The imaging device is used to image the focused detection object to obtain an image of the detection object, wherein the image of the detection object is used for feature detection.

2. The optical detection system according to claim 1, characterized in that: The illumination light intensity detection device is coaxially arranged with the illumination optical system along the direction of the illumination light beam.

3. The optical detection system according to claim 1, characterized in that: The illumination light intensity detection device comprises a first optical component, a photoelectric detector and a signal processing unit, wherein: The first optical component is used to receive the illumination beam from the coupled beam and isolate the focus detection beam; The photoelectric detector is used to convert the optical signal of the illumination light beam after passing through the first optical component into an electrical signal; The signal processing unit is used to measure the energy of the illumination light beam based on the electrical signal.

4. The optical detection system according to claim 3, characterized in that: The illumination light intensity detection device further comprises a second optical component, wherein: The second optical component is arranged on the optical path between the first optical component and the photodetector, and is used to focus the illumination light beam passing through the first optical component onto the photodetector.

5. The optical detection system according to claim 4, characterized in that: The illumination light intensity detection device further comprises a third optical component, wherein: The third optical component is used to attenuate the energy of the illumination light beam passing through the second optical component to an energy detection range of the photodetector.

6. The optical detection system according to claim 5, characterized in that: The first optical component includes at least one of a bandpass filter, a high-pass filter and a low-pass filter, the second optical component includes a lens group, and the third optical component includes an optical attenuation plate.

7. The optical detection system according to claim 4, characterized in that: The second optical component is perpendicular to the illumination light beam after passing through the first optical component.

8. The optical detection system according to claim 7, characterized in that: At least one component among the first optical component, the third optical component and the photodetector is tilted relative to the second optical component.

9. The optical detection system according to claim 2, characterized in that: The coupler includes a dichroic mirror, which is used to transmit the focusing light beam to the detection object, transmit the light beam with a first energy ratio in the illumination light beam to the illumination light intensity detection device, and reflect the light beam with a second energy ratio in the illumination light beam to the detection object, wherein the first energy ratio is smaller than the second energy ratio.

10. The optical detection system according to claim 1, characterized in that: The illumination optical system comprises: an illumination light source, and at least one of a beam shaping device, an optical modulation device and an illumination tube lens arranged in sequence along the propagation direction of the illumination light beam; The illumination light source is used to emit an initial light beam; The beam shaping device adjusts the divergence angle of the initial light beam so that the initial light beam has a preset aperture angle and a preset field angle; The optical modulation device is used to select an illumination light beam of a preset wavelength band from the initial light beam after the divergence angle is adjusted; The illumination tube lens is used to adjust the propagation direction of the illumination light beam and make the adjusted illumination light beam incident on the coupler.

11. The optical detection system according to claim 10, characterized in that: The beam shaping device includes at least one of a lens group, a homogenizing tube and frosted glass, the optical modulation device includes at least one of a filter, an attenuation plate, a polarizer and an aperture, and the lighting tube lens includes a lens group.

12. The optical detection system according to claim 1, characterized in that: The imaging device is arranged on the optical path between the coupler and the detection object through a beam splitter along the direction of the coupled illumination light beam.

13. The optical detection system according to claim 12, characterized in that: The imaging device comprises an objective lens and an imaging assembly, wherein the objective lens is arranged on the optical path of the illumination beam transmitted by the beam splitter, and is used to transmit the illumination beam and the focus detection beam transmitted by the beam splitter to the detection object, and receive the illumination beam and the focus detection beam reflected by the detection object; The beam splitter is used to transmit the focus detection beam reflected by the detection object to the detection light emitting device, and reflect the illumination beam reflected by the detection object to the imaging component; The imaging component is arranged on the optical path of the illumination light beam reflected by the beam splitter, and is used to image the detection object according to the illumination light beam reflected by the detection object.

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