阅读说明：本技术 探测装置、路侧传感设备以及智能交通系统 (Detection device, roadside sensing equipment and intelligent transportation system ) 是由 张庆舜 于 2021-08-23 设计创作，主要内容包括：本公开提供了探测装置、路侧传感设备以及智能交通系统,涉及传感设备技术领域,尤其涉及车路协同中的路侧传感设备技术领域。其中,探测装置包括用于探测同一目标区域的雷达组件和相机组件,雷达组件包括第一控制与处理模块、发射模块和雷达接收模块,第一控制与处理模块用于控制发射模块发射激光,以及控制雷达接收模块接收激光的反射光并生成雷达传感信息；相机组件包括第二控制与处理模块和相机接收模块,第二控制与处理模块用于控制相机接收模块接收反射光并生成图像传感信息。根据本公开的技术,在光照条件较差的场景下可以利用发射模块发射的激光对相机组件进行补光,无需单独为相机组件设置补光设备,从而降低了探测装置的设备成本。(The utility model provides a detecting device, roadside sensing equipment and intelligent transportation system relates to sensing equipment technical field, especially relates to roadside sensing equipment technical field in the vehicle and road is in coordination. The detection device comprises a radar component and a camera component which are used for detecting the same target area, the radar component comprises a first control and processing module, a transmitting module and a radar receiving module, and the first control and processing module is used for controlling the transmitting module to transmit laser and controlling the radar receiving module to receive reflected light of the laser and generate radar sensing information; the camera assembly comprises a second control and processing module and a camera receiving module, and the second control and processing module is used for controlling the camera receiving module to receive the reflected light and generate image sensing information. According to the technology disclosed by the invention, the camera assembly can be supplemented with light by utilizing the laser emitted by the emitting module under the scene with relatively poor illumination condition, and the light supplementing equipment does not need to be independently arranged for the camera assembly, so that the equipment cost of the detection device is reduced.)

1. A detection apparatus comprising a radar component and a camera component for detecting the same target area;

the radar assembly comprises a first control and processing module, a transmitting module and a radar receiving module, wherein the first control and processing module is used for controlling the transmitting module to transmit laser and controlling the radar receiving module to receive reflected light of the laser and generate radar sensing information;

the camera assembly comprises a second control and processing module and a camera receiving module, wherein the second control and processing module is used for controlling the camera receiving module to receive the reflected light and generate image sensing information.

2. The detection device according to claim 1, wherein the first control and processing module and the second control and processing module respectively receive a synchronization signal and respectively control the radar receiving module and the camera receiving module to synchronously operate based on the synchronization signal.

3. The detection apparatus according to claim 2, wherein the first control and processing module is configured to control the emission module to emit laser light at a first preset time interval in response to the synchronization signal;

the second control and processing module is configured to, in response to the synchronization signal, control the camera receiving module to receive the reflected light at intervals of a second preset duration, which is an integral multiple of the first preset duration, and generate the image sensing information.

4. The detection device according to claim 2, wherein the radar component and the camera component are respectively provided with a synchronization interface, and the first control and processing module and the second control and processing module respectively receive the synchronization signal through the corresponding synchronization interfaces.

5. The detection device according to claim 1, wherein the detection field of view of the radar assembly is formed by splicing a plurality of detection areas, the transmission module comprises a plurality of transmission areas, and the plurality of transmission areas correspond to the plurality of detection areas in a one-to-one manner;

the first control and processing module is further configured to control the plurality of emission areas to sequentially emit laser according to a preset sequence within a first preset time period.

6. The detection device according to claim 1, wherein the camera receiving module comprises an infrared sensor, and the laser light emitted by the emitting module is near infrared light.

7. The detection apparatus of claim 6, wherein the radar assembly further comprises:

and the light supplementing module is integrated with the transmitting module and is used for transmitting white light.

8. The detection apparatus of claim 1, wherein the radar receiving module comprises a single photon avalanche diode array.

9. The detection apparatus of claim 1, wherein the first control and processing module is configured to receive the radar sensing information and generate radar data;

the second control and processing module is configured to receive the image sensing information and generate image data.

10. A roadside sensing device characterized by comprising:

a detection device according to any one of claims 1 to 9;

and the synchronous control device is used for sending synchronous signals to the first control and processing module and the second control and processing module.

11. An intelligent transportation system, comprising:

the roadside sensing apparatus of claim 10;

and the roadside computing unit is used for receiving the image data and the radar data from the roadside sensing equipment and executing data computing processing.

Technical Field

The utility model relates to an intelligent transportation technical field especially relates to roadside sensing equipment technical field in vehicle and road is in coordination.

Background

In the related art, the road junction is monitored at the road end by adopting a mode of combining a laser radar and a monitoring camera, and when the monitoring camera is used in an extremely low illumination scene such as at night, a high-power mixed light supplement or a near-infrared optical module is generally required to be independently arranged for light supplement, so that the hardware cost is high.

Disclosure of Invention

The present disclosure provides a detection device, a roadside sensing device and an intelligent transportation system.

According to an aspect of the present disclosure, a detection apparatus is provided, which includes a radar component and a camera component for detecting a same target area, the radar component includes a first control and processing module, a transmitting module and a radar receiving module, the first control and processing module is configured to control the transmitting module to transmit laser light, and control the radar receiving module to receive reflected light of the laser light and generate radar sensing information; the camera assembly comprises a second control and processing module and a camera receiving module, and the second control and processing module is used for controlling the camera receiving module to receive the reflected light and generate image sensing information.

According to another aspect of the present disclosure, there is provided a roadside sensing device including:

the detection device according to the above embodiment of the present disclosure;

and the synchronous control device is used for sending synchronous signals to the first control and processing module and the second control and processing module.

According to another aspect of the present disclosure, there is provided an intelligent transportation system including:

the roadside sensing device according to the above embodiment of the present disclosure;

and the roadside calculation unit is used for receiving the image data and the radar data from the roadside sensing equipment and executing data calculation processing.

According to the technology disclosed by the invention, the camera receiving module is supplemented with light by utilizing the transmitting module of the radar component, so that the light signal intensity of reflected light is improved under the scene of insufficient illumination, and the image quality and the signal-to-noise ratio of image data output by the camera component are improved. Therefore, according to the detection device disclosed by the embodiment of the disclosure, a better light supplementing effect can be realized for the camera assembly in a scene with a poorer illumination condition, and a light supplementing device does not need to be arranged for the camera assembly independently, so that the equipment cost of the detection device is reduced.

It should be understood that the statements in this section do not necessarily identify key or critical features of the embodiments of the present disclosure, nor do they limit the scope of the present disclosure. Other features of the present disclosure will become apparent from the following description.

Drawings

The drawings are included to provide a better understanding of the present solution and are not to be construed as limiting the present disclosure. Wherein:

FIG. 1 shows a schematic structural diagram of a detection apparatus according to an embodiment of the present disclosure;

fig. 2 shows a schematic structural diagram of a roadside sensing device according to an embodiment of the disclosure.

Description of reference numerals:

a roadside sensing device 1;

a detection device 100;

a radar component 10; a first control and processing module 11; a transmitting module 12; a radar receiving module 13;

a camera assembly 20; a second control and processing module 21; a camera receiving module 22;

a synchronization control device 200; a data processing apparatus 300.

Detailed Description

Exemplary embodiments of the present disclosure are described below with reference to the accompanying drawings, in which various details of the embodiments of the disclosure are included to assist understanding, and which are to be considered as merely exemplary. Accordingly, those of ordinary skill in the art will recognize that various changes and modifications of the embodiments described herein can be made without departing from the scope and spirit of the present disclosure. Also, descriptions of well-known functions and constructions are omitted in the following description for clarity and conciseness.

A probe apparatus 100 according to an embodiment of the present disclosure is described below with reference to fig. 1.

As shown in fig. 1, a detection apparatus 100 according to an embodiment of the present disclosure includes a radar assembly 10 and a camera assembly 20 for detecting the same target area.

The radar assembly 10 includes a first control and processing module 11, a transmitting module 12 and a radar receiving module 13, wherein the first control and processing module 11 is configured to control the transmitting module 12 to transmit laser light, and control the radar receiving module 13 to receive reflected light of the laser light and generate radar sensing information. Wherein the reflected light is formed by the laser encountering an obstacle. The camera assembly 20 includes a second control and processing module 21 and a camera receiving module 22, and the second control and processing module 21 is configured to control the camera receiving module 22 to receive the reflected light and generate image sensing information.

The detection device 100 of the embodiment of the present disclosure may be applied to the roadside sensing apparatus 1, the roadside sensing apparatus 1 is installed in a roadside environment, and the radar component 10 and the camera component 20 are used for detecting the same target region in the roadside environment. It will be appreciated that the detection field of view of the radar assembly 10 and the monitoring field of view of the camera assembly 20 at least partially coincide, and that the fields of view of the coincident portions correspond to the same target area.

Further, the radar receiving module 13 and the camera receiving module 22 may determine the field of view of the detection field of the radar component 10 and the field of view of the monitoring field of the camera component 20 at the overlapped portion by means of internal and external reference calibration.

For example, the Laser Emitting unit may employ a Vertical-Cavity Surface-Emitting Laser (VCSEL) or a semiconductor Laser (LD). Preferably, the laser emitting unit may employ a vertical cavity surface emitting laser. The vertical cavity surface emitting laser has the advantages of high output power, high conversion efficiency, high laser quality and the like, and can improve the sensing precision of a radar module and a camera module, reduce the operation power consumption and improve the working reliability.

It should be noted that the radar receiving module 13 and the camera receiving module 22 may respectively receive the reflected light of the laser, that is, the radar receiving module 13 and the camera receiving module 22 respectively generate corresponding electrical signals based on the optical signal transmitted by the same transmitting module 12, so as to implement detection of the same target area.

In the embodiment of the present disclosure, the radar receiving module 13 and the camera receiving module 22 are both photoelectric sensors, and the photoelectric principles of the two are substantially similar. Unlike millimeter-wave radars in the related art, the radar receiving module 13 in the embodiment of the present disclosure uses light as a dominant medium, and can achieve detection accuracy at a pixel level of a target region.

For example, the radar receiving module 13 of the radar component 10 may employ a Single Photon Avalanche Diode (SPAD) array or a Silicon photomultiplier (SIPM) to achieve pixel-level detection accuracy.

Illustratively, the camera assembly 20 may employ an infrared camera having a day and night confocal function. Specifically, the infrared camera starts an RGB (Red Green Blue) working mode and outputs image data in an RGB format in the daytime; the infrared camera turns on the infrared mode at night, and the camera receiving module 22 of the infrared camera may include an infrared receiver, and the infrared camera outputs image data in a gray graph format based on the received infrared light. Based on the image data in the grayscale map format, a distance value of the target region can be obtained.

For example, the radar data output by the radar component 10 may include point cloud data, distance values of respective laser points, and intensity values, and the image data output by the camera component 20 may include intensity values and distance values of respective pixel points. Based on the intensity value in the radar data, the intensity value in the image data, the distance value in the radar data and the distance value in the image data, the enhanced distance value and intensity value can be obtained through fusion calculation processing, and therefore the detection precision of the target area is improved in a scene with dark light.

It should be noted that, in the embodiment of the present disclosure, the radar component 10 and the camera component 20 may be provided integrally or separately. The transmitting module 12 may be integrated with the radar component 10 or integrated with the camera component 20.

According to the detection apparatus 100 of the embodiment of the present disclosure, the transmitting module 12 shared by the radar receiving module 13 and the camera receiving module 22 is provided, and the radar receiving module 13 and the camera receiving module 22 respectively generate radar sensing information and image sensing information based on reflected light formed by laser light transmitted by the transmitting module 12, based on which, the transmitting module 12 of the radar component 10 is used to supplement light to the camera receiving module 22, so as to improve the light signal intensity of the reflected light of the camera receiving module 22 in a scene with insufficient light, thereby improving the image quality and the signal-to-noise ratio of image data output by the camera component 20. Therefore, according to the detection device 100 of the embodiment of the present disclosure, a better light compensation effect can be achieved for the camera assembly 20 in a scene with a poor illumination condition, and a light compensation device does not need to be separately provided for the camera assembly 20, so that the device cost of the detection device 100 is reduced.

In one embodiment, the first control and processing module 11 and the second control and processing module 21 respectively receive the synchronization signal, and respectively control the radar receiving module 13 and the camera receiving module 22 to synchronously operate based on the synchronization signal.

In one example, the first and second control and processing modules 11 and 21, respectively, receive a synchronization signal to synchronize the time information of the camera assembly 20 with the time information of the radar assembly 10. The first control and processing module 11 controls the transmitting module 12 to transmit laser according to the preset time point and period of transmitting laser by the transmitting module 12 in the synchronous signal, and controls the radar receiving module 13 to continuously work; the second control and processing module 21 controls the camera receiving module 22 to intermittently operate according to the preset photographing time point and photographing interval of the camera component 20 in the synchronization signal.

In another example, the first control and processing module 11 and the second control and processing module 21 may communicate with each other, and the first control and processing module 11 sends a synchronization signal to the second control and processing module 21, so that the time information of the first control and processing module 11 and the second control and processing module 21 is synchronized, and the camera receiving module 22 is controlled to operate according to the photographing time point and the photographing period of the camera assembly 20 preset in the synchronization signal.

Through the above embodiment, the time information of the radar sensing information output by the radar receiving module 13 and the time information of the image sensing information output by the camera receiving module 22 can be synchronized, so that the reliability and accuracy of the subsequent data fusion processing on the radar sensing data and the image sensing data can be ensured.

In one embodiment, the radar assembly 10 and the camera assembly 20 are each provided with a synchronization interface, and the first control and processing module 11 and the second control and processing module 21 each receive a synchronization signal via the corresponding synchronization interface.

Illustratively, the synchronization interface may employ an I/O (Input/Output) interface to achieve hardware-level synchronization between the radar component 10 and the camera component 20.

The signal synchronization is performed through the I/O interface, and the time information difference between the radar receiving module 13 and the camera receiving module 22 can be controlled to be in a level below microseconds, so that the radar sensing data and the camera sensing data are highly synchronized.

In one embodiment, the first control and processing module 11 is configured to control the emitting module 12 to emit the laser light for a first preset time interval in response to the synchronization signal. The second control and processing module 21 is configured to control the camera receiving module 22 to receive the reflected light at a second preset time interval in response to the synchronization signal, and generate the image sensing information, wherein the second preset time interval is an integral multiple of the first preset time interval.

In other words, the first preset duration is a scanning period of the radar component 10, and the transmitting module 12 transmits laser light once in one scanning period. Accordingly, the radar receiving module 13 receives the reflected light of the primary laser, completes the primary scanning of the target area, and generates the radar sensing information of the single frame of the target area. The second preset duration is the shutter interval time of the camera assembly 20, and the camera receiving module 22 receives the emitted light of the laser once every second preset duration, completes one shooting of the target area, and generates single-frame image sensing information of the target area.

Wherein the second preset time period is an integer multiple of the first preset time period, that is, the shutter interval time of the camera assembly 20 is an integer multiple of the scanning period of the radar assembly 10, and the timestamp of the reflected light received by the camera receiving module 22 is an integer multiple of the timestamp of the reflected light received by the radar receiving module 13.

Through the above embodiment, it can be ensured that the laser emitted by the emitting module 12 can traverse the target area within the time interval of the camera assembly 20 shooting the frame image, so as to achieve the purpose of supplementing light to the camera assembly 20 and ensure the image quality of the image data.

In one embodiment, the detection field of view of the radar assembly 10 is formed by splicing a plurality of detection areas, and the transmitting module 12 includes a plurality of transmitting areas, which correspond to the plurality of detection areas one by one. The first control and processing module 11 is further configured to control the plurality of emission areas to sequentially emit the laser light in a preset order within a first preset time period.

For example, the emitting module 12 may adopt a surface laser, the emitting module 12 includes a plurality of laser emitting subunits arranged in an array, each emitting area is formed by a plurality of laser emitting subunits, and the first controlling and processing module 11 may individually control one of the emitting areas to emit laser. Therefore, the emitting area corresponding to the key area can be controlled to emit laser aiming at the key area in the plurality of detecting areas of the detecting field of view, so that the laser emitted by the emitting area is controlled to light the key area, and the aim of targeted light supplement is fulfilled.

Further, the first control and processing module 11 may control the plurality of emitting modules 12 to sequentially emit the laser light according to a preset sequence, so that the laser light sequentially illuminates the plurality of detecting regions of the detecting field of view. Therefore, the laser emitted by the emitting module 12 may traverse a plurality of detection areas of the detection field according to a preset sequence, and after completing one traversal, the radar component 10 acquires frame data of the target area.

Through the embodiment, the detection of the detection view field in the sub-areas can be realized, and each detection area can be independently controlled by controlling the emission area to independently emit laser, so that the detection is carried out on a specific detection area in the detection view field. In addition, the first control and processing module 11 controls the plurality of emitting areas to sequentially emit laser according to a preset sequence, so that the frequency and duty ratio of the laser emitted by the laser can be increased, the intensity of the laser is increased, and the light supplement effect on the camera receiving module 22 is improved.

In one embodiment, the radar receiving module 13 comprises a single photon avalanche diode array.

It will be appreciated that a single photon avalanche diode is an avalanche photodiode operating in geiger mode. The bias voltage of the avalanche photodiode in the Geiger mode is higher than the breakdown voltage, the avalanche photodiode can enter a reverse breakdown state after receiving photons, and a large reverse current is passed, so that the function of detecting the photons is realized.

Illustratively, the single photon avalanche diode can be processed by a Complementary Metal Oxide Semiconductor (CMOS) process, which can result in a large-batch and highly integrated single photon avalanche diode array, wherein the size of the single photon avalanche diode is only 15um × 15 um. Therefore, the size of the radar sensing unit can be further reduced on the basis of ensuring that the radar sensing unit has high pixel detection capability.

In other examples of the present disclosure, the radar receiving module 13 may further include a Silicon Photomultiplier (SIPM). Specifically, the silicon photomultiplier is composed of a plurality of (several to several thousands) avalanche photodiode units, each avalanche photodiode unit is formed by connecting an avalanche photodiode and a large-resistance quenching resistor in series, and the operating mode of the avalanche photodiode is a geiger mode so as to form a single photon avalanche diode. The plurality of avalanche photodiode units are connected in parallel to form a surface receiving array. The silicon photomultiplier has a large dynamic range, so that the detection precision of the radar sensing unit can be improved. In addition, the radar receiving module 13 may be packaged with a plurality of silicon photomultiplier tubes to form a plurality of surface receiving arrays, so as to improve the receiving performance of the reflected laser pulse signals and reduce the probability of missed detection of the laser pulse signals.

In one embodiment, the camera receiving module 22 includes an Infrared sensor, and the laser light emitted by the emitting module 12 is Near Infrared (NIR).

Illustratively, the camera receiving module 22 may employ an infrared sensor capable of receiving near-infrared light. It is understood that the near infrared light is an electromagnetic wave between visible light and mid-infrared light, and particularly, an electromagnetic wave having a wavelength in a range of 780 to 2526nm, wherein the near infrared region may be divided into two regions of a near infrared short wave (780 to 1100nm) and a near infrared long wave (1100 to 2526 nm). The wavelength of the near infrared light emitted by the emitting module 12 may be 850 nanometers or 940 nanometers.

Through the above embodiment, on the basis that the detection function of the radar component 10 is satisfied by the laser emitted by the emitting module 12, it is ensured that the laser emitted by the emitting module 12 can be sensed by the camera receiving module 22, and the reliability and stability of the light supplement of the emitting module 12 to the camera component 20 are ensured.

In one embodiment, the radar assembly 10 further includes a light supplement module, which is integrated with the transmitting module 12 and is configured to transmit white light.

It will be appreciated that white light is a composite light, typically a mixture of two or three wavelengths of light. The white light may be used to fill the radar receiving module 13 and the camera receiving module 22 with light together.

Illustratively, the fill-in module may be a white light laser, and a plurality of white light lasers are integrally disposed to form a white light fill-in area among the plurality of emission areas of the emission module 12. The white light supplementary lighting area is arranged corresponding to a specific key area in the plurality of detection areas in the detection field, namely, the white light emitted by the plurality of white light lasers in the white light supplementary area can cover the key area, so that the purpose of supplementary lighting of the key area is achieved. The key area may be an area with a longer distance in the detection field of view, so as to reinforce the illumination intensity and improve the detection effect of the radar receiving module 13 and the camera receiving module 22.

Therefore, light can be supplemented to a key area in a detection view field of the radar component 10 in a targeted manner, so that the detection precision and the detection effect of the radar sensor on a long-distance target object are further improved.

In one embodiment, the first control and processing module 11 is configured to receive radar sensing information and generate radar data; the second control and processing module 21 is configured to receive the image sensing information and generate image data.

Illustratively, the first control and processing module 11 includes distance information and intensity information in the radar data generated based on the radar sensing information, and the second control and processing module 21 includes brightness information in the image data generated based on the image sensing information. The radar data and the image data are transmitted together to the data processing device 300 of the roadside computing unit, the intensity information and the brightness information have high correlation, and the data processing device 300 performs weighted superposition based on the intensity information and the brightness information to obtain brightness fusion information. Based on the luminance fusion information, image quality enhancement can be performed on the image data or the radar data, thereby improving the detection accuracy of the roadside sensing device 1.

Therefore, the detection device 1 can output radar data and image data, and can enhance the radar data or the image data by utilizing the fusion information of the radar data and the image data, thereby improving the output precision of the detection device 1.

As another aspect of the disclosed embodiment, a roadside sensing device 1 is also provided.

As shown in fig. 2, the roadside sensing device 1 includes the detection apparatus 100 and the synchronization control apparatus 200 according to the above-described embodiment of the present disclosure. The synchronization control device 200 is configured to send synchronization signals to the first control and processing module 11 and the second control and processing module 21.

Illustratively, the synchronization signal is used to instruct the first control and processing module 11 to control the transmitting module 12 to transmit laser light once every a first preset time interval according to preset time information and a time stamp, and instruct the second control and processing module 21 to control the camera receiving module 22 to shoot the target area once every a second preset time interval according to preset time information and a time stamp. And the second preset time length is integral multiple of the first preset time length.

Thereby, it is possible to realize synchronous control of the radar unit 10 and the camera unit 20 so that the radar data output from the radar unit 10 and the image data output from the camera unit 20 are kept time-synchronized.

Illustratively, the roadside sensing device 1 includes a base body, and the detection device 100 is disposed on the base body. The power supply module is integrated in the base body and used for respectively supplying power to the radar component 10 and the camera component 20.

Illustratively, the roadside sensing device 1 further includes a data processing device 300, and the data processing device 300 is configured to perform weighted overlap-add processing to obtain luminance fusion information according to the intensity information in the radar data and the luminance information in the image data. And based on the brightness fusion information, performing structural feature extraction on the radar data to obtain structural data. The structured data may be transmitted to the roadside computing unit to perform corresponding decision-making processing.

According to the roadside sensing device 1 of the embodiment of the present disclosure, by using the detection apparatus 100 according to the above-described embodiment of the present disclosure, a better light compensation effect can be achieved for the camera assembly 20 in a scene with a poor illumination condition, and it is not necessary to separately set a light compensation device for the camera assembly 20, thereby reducing the hardware cost of the roadside sensing device 1.

Other configurations of the roadside sensing device 1 of the above-described embodiment may be adopted for various technical solutions known by those skilled in the art now and in the future, and will not be described in detail here.

As another aspect of the disclosed embodiment, an intelligent transportation system is also provided.

The intelligent transportation system comprises the roadside sensing device 1 and a roadside computing unit according to the above-mentioned embodiment of the present disclosure, wherein the roadside computing unit is used for receiving radar data and image data from the roadside sensing device 1 and executing corresponding data computing processing.

Illustratively, the roadside computing unit may be an edge computing unit, and is configured to receive radar data and image data sent by the roadside sensing device 1, and perform corresponding decision processing to obtain relevant information of a target object in a target area, so as to implement other functions such as prediction perception, path planning, and early warning for the target object.

The intelligent transportation system can further comprise a cloud server and a vehicle-end server, and any two of the roadside computing unit, the cloud server and the vehicle-end server can perform information interaction.

In the description of the present specification, it is to be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the present disclosure and to simplify the description, but are not intended to indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and are therefore not to be considered limiting of the present disclosure.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present disclosure, "a plurality" means two or more unless specifically limited otherwise.

In the present disclosure, unless otherwise expressly stated or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integral; the connection can be mechanical connection, electrical connection or communication; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meaning of the above terms in the present disclosure can be understood by those of ordinary skill in the art as appropriate.

In the present disclosure, unless expressly stated or limited otherwise, the first feature "on" or "under" the second feature may comprise the first and second features being in direct contact, or may comprise the first and second features being in contact, not directly, but via another feature in between. Also, the first feature being "on," "above" and "over" the second feature includes the first feature being directly on and obliquely above the second feature, or merely indicating that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature includes the first feature being directly above and obliquely above the second feature, or simply meaning that the first feature is at a lesser level than the second feature.

The above disclosure provides many different embodiments or examples for implementing different features of the disclosure. In order to simplify the disclosure of the present disclosure, specific example components and arrangements are described above. Of course, they are merely examples and are not intended to limit the present disclosure. Moreover, the present disclosure may repeat reference numerals and/or reference letters in the various examples, which have been repeated for purposes of simplicity and clarity and do not in themselves dictate a relationship between the various embodiments and/or arrangements discussed.

The above detailed description should not be construed as limiting the scope of the disclosure. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions may be made in accordance with design requirements and other factors. Any modification, equivalent replacement, and improvement made within the spirit and principle of the present disclosure should be included in the scope of protection of the present disclosure.