阅读说明：本技术 一种用于光学低相干间距测量的调焦装置 (Focusing device for optical low coherence interval measurement ) 是由 邢利娜 何益 高峰 张欣 史国华 于 2019-09-24 设计创作，主要内容包括：本发明提供一种用于光学低相干间距测量的调焦装置,该装置通过驱动组件驱动转动组件,通过导向结构带动可动筒及胶合透镜运动进行焦距调节。本发明还涉及一种调焦镜头。通过脉冲型的步进电机输入脉冲的数量来控制胶合透镜的运动距离,镜头的焦距可以大范围调整,便于在光学低相干间距测量时将测量光聚焦于待测样品的光学面附近。采用标准的光纤接头,以满足在不同的光纤系统中替换使用,提高利用率。该装置实现将点光源准直或者聚焦,具有结构简单,易于装配调整,调整分辨率高的优点。(The invention provides a focusing device for measuring an optical low-coherence interval. The invention also relates to a focusing lens. The movement distance of the cemented lens is controlled by the number of pulses input by the pulse type stepping motor, the focal length of the lens can be adjusted in a large range, and the measurement light is conveniently focused near the optical surface of a sample to be measured during optical low-coherence distance measurement. And standard optical fiber connectors are adopted to meet the requirement of replacement in different optical fiber systems, so that the utilization rate is improved. The device realizes the collimation or the focusing of a point light source, and has the advantages of simple structure, easy assembly and adjustment and high adjustment resolution.)

1. A focusing device for optical low coherence interval measurement is characterized by comprising a focusing body, wherein the focusing body comprises a driving assembly, a transmission assembly, a lens barrel, a guide structure and a sleeve, the driving assembly is used for driving the transmission assembly to drive the sleeve to rotate, and the sleeve is arranged on the outer wall of the lens barrel;

a movable cylinder is arranged in the lens cone, and one end of the guide structure is fixedly arranged on the movable cylinder; the other end of the guide structure is connected with the lens cone and the sleeve;

the driving assembly drives the transmission assembly to drive the sleeve to rotate, and the guide structure drives the movable barrel and the cemented lens therein to move along the axis direction of the lens barrel under the driving of the sleeve so as to adjust the focal length.

2. The focusing device for optical low coherence interval measurement according to claim 1, wherein the guiding structure comprises a spiral groove, a first through groove and a guiding post, the spiral groove is located on the cylinder wall of the sleeve, the first through groove is located on the cylinder wall of the lens barrel and extends along the axial direction of the cylinder wall, one end of the guiding post is fixedly mounted on the movable cylinder, and the other end of the guiding post passes through the first through groove and moves along the spiral groove.

3. A focusing mechanism for optical low coherence interval measurement according to claim 1 or 2, wherein said transmission assembly comprises a first gear and a second gear, said first gear being fixedly mounted to said drive assembly, said first gear engaging said second gear; the second gear is fixedly connected with the sleeve;

the inner wall of the second gear comprises a plurality of bulges, and the sleeve comprises grooves matched with the bulges;

the driving assembly drives the first gear, the first gear drives the second gear to rotate, the second gear drives the sleeve to rotate, and the guide column is driven by the sleeve to move so that the movable cylinder and the cemented lens move together along the first through groove.

4. The focusing apparatus for optical low coherence interval measurement according to claim 1, wherein the driving assembly is a pulse stepping motor having a zero reset function, and the moving distance of the movable barrel is controlled by setting the number of pulses of the pulse stepping motor.

5. The apparatus of claim 3, wherein the focusing body further comprises a fiber fixing barrel and a fiber connector, the fiber fixing barrel is fixedly connected to the lens barrel, and the fiber is fixed in the fiber fixing barrel through the fiber connector.

6. The apparatus of claim 5, wherein the barrel comprises a first barrel and a second barrel, the first barrel and the second barrel are integrally formed, the movable barrel is mounted in the first barrel, the first barrel is adjacent to the second gear, and the movable barrel moves in the first barrel; and the plurality of cemented lenses are fixedly arranged in the second lens cone, and the second lens cone is close to the optical fiber connector.

7. The focusing device for optical low coherence interval measurement according to claim 3, wherein the focusing body further comprises a lens fixing seat, a fixing seat upper cover and a base, the lens fixing seat is fixedly mounted on the base, the lens fixing seat comprises a notch matched with the outer wall of the lens barrel, and the lens barrel is fixedly mounted on the lens fixing seat through the fixing seat upper cover; the fixing seat upper cover comprises a clamping part and a fixing part, the clamping part is used for matching with the outer wall of the lens cone, and the fixing part is used for fixing the lens cone on the lens fixing seat.

8. The apparatus of claim 7, wherein the focus body further comprises a motor mount for fixing the motor to the base and a trimming pad connected to the motor mount for compensating for the accuracy of the engagement of the first and second gears.

9. The apparatus of claim 1, wherein the barrel or barrel includes a plurality of threaded clamping or spacer rings for securing a plurality of cemented lenses within the barrel or barrel.

10. A focus lens comprising the focus body according to claim 1.

Technical Field

The invention relates to the technical field of optical engineering, in particular to a focusing device for optical low coherence interval measurement.

Background

The measurement of the optical surface spacing is one of the core supporting means for the adjustment and integration of precise optical components and image quality evaluation. At the present stage, the traditional contact measurement is adopted in most occasions for measuring the distance between the optical surfaces in China, the measurement mode is not only easy to damage the surfaces of the precision lenses, but also only can realize the measurement of the single lens, and the measurement of the whole system cannot be realized. By adopting the optical low-coherence measurement technology, the two problems can be well solved. When the optical low-coherence technique is used to realize the test, firstly, a point light source from a light source needs to be collimated by an optical fiber collimator.

However, the traditional commercial optical fiber collimator has the problems of small adjustable focal length range and large dispersion.

Disclosure of Invention

To overcome the deficiencies of the prior art, the present invention provides a focusing apparatus for optical low coherence interval measurement. The invention controls the movement distance between the movable cylinder and the cemented lens through the motor, the focal length of the lens can be adjusted and increased in a large range, and the focus of the light beam is ensured to move to a required position.

The invention provides a focusing device for measuring an optical low coherence interval, which comprises a focusing body, wherein the focusing body comprises a driving assembly, a transmission assembly, a lens cone, a guide structure and a sleeve, the driving assembly is used for driving the transmission assembly to drive the sleeve to rotate, and the sleeve is arranged on the outer wall of the lens cone;

a movable cylinder is arranged in the lens cone, and one end of the guide structure is fixedly arranged on the movable cylinder; the other end of the guide structure is connected with the lens cone and the sleeve;

the driving assembly drives the transmission assembly to drive the sleeve to rotate, and the guide structure drives the movable barrel and the cemented lens therein to move along the axis direction of the lens barrel under the driving of the sleeve so as to adjust the focal length.

Preferably, the guide structure includes a spiral groove, a first through groove, and a guide post, the spiral groove is located on the cylinder wall of the sleeve, the first through groove is located on the cylinder wall of the lens barrel and extends along the axis direction of the first through groove, one end of the guide post is fixedly mounted on the movable cylinder, and the other end of the guide post passes through the first through groove and moves along the spiral groove.

Preferably, the transmission assembly comprises a first gear and a second gear, the first gear is fixedly mounted on the driving assembly, and the first gear is meshed with the second gear; the second gear is fixedly connected with the sleeve;

the inner wall of the second gear comprises a plurality of bulges, and the sleeve comprises grooves matched with the bulges;

the driving assembly drives the first gear, the first gear drives the second gear to rotate, the second gear drives the sleeve to rotate, and the guide column is driven by the sleeve to move so that the movable cylinder and the cemented lens move together along the first through groove.

Preferably, the driving component is a pulse stepping motor with a zero reset function, and the moving distance of the movable cylinder is controlled by setting the pulse number of the pulse stepping motor.

Preferably, the focusing body further comprises an optical fiber fixing cylinder and an optical fiber connector, the optical fiber fixing cylinder is fixedly connected with the lens barrel, and the optical fiber is fixed in the optical fiber fixing cylinder through the optical fiber connector.

Preferably, the lens barrel includes a first lens barrel and a second lens barrel, the first lens barrel and the second lens barrel are integrally formed, the movable barrel is installed in the first lens barrel, the first lens barrel is close to the second gear, and the movable barrel moves in the first lens barrel; and the plurality of cemented lenses are fixedly arranged in the second lens cone, and the second lens cone is close to the optical fiber connector.

Preferably, the focusing body further comprises a lens fixing seat, a fixing seat upper cover and a base, the lens fixing seat is fixedly mounted on the base, the lens fixing seat comprises a notch matched with the outer wall of the lens cone, and the lens cone is fixedly mounted on the lens fixing seat through the fixing seat upper cover; the fixing seat upper cover comprises a clamping part and a fixing part, the clamping part is used for matching with the outer wall of the lens cone, and the fixing part is used for fixing the lens cone on the lens fixing seat.

Preferably, the focusing body further comprises a motor base and a trimming pad, the motor base fixes the motor on the base, the trimming pad is connected with the motor base, and the trimming pad is used for compensating the meshing precision of the first gear and the second gear.

Preferably, the lens barrel or the movable barrel comprises a plurality of threaded pressing rings or spacing rings, and the threaded pressing rings or the spacing rings are used for fixing a plurality of cemented lenses in the lens barrel or the movable barrel.

A focus lens includes a focus body of a focusing apparatus for optical low coherence interval measurement.

Compared with the prior art, the invention has the beneficial effects that:

the invention discloses a focusing device for optical low coherence interval measurement. The movement distance of the cemented lens is controlled by the number of pulses input by the pulse type stepping motor, the focal length of the lens can be adjusted in a large range, and the measurement light is conveniently focused near the optical surface of a sample to be measured during optical low-coherence distance measurement. The standard optical fiber connector can be used in different optical fiber systems, and utilization rate is improved. The device realizes the collimation or the focusing of a point light source, and has the advantages of simple structure, easy assembly and adjustment and high adjustment resolution.

The foregoing description is only an overview of the technical solutions of the present invention, and in order to make the technical solutions of the present invention more clearly understood and to implement them in accordance with the contents of the description, the following detailed description is given with reference to the preferred embodiments of the present invention and the accompanying drawings. The detailed description of the present invention is given in detail by the following examples and the accompanying drawings.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the invention and together with the description serve to explain the invention without limiting the invention. In the drawings:

FIG. 1 is a perspective view of a focusing apparatus for optical low coherence gap measurement according to the present invention;

FIG. 2 is a cross-sectional view of a focusing apparatus for optical low coherence gap measurement in accordance with the present invention;

FIG. 3 is a side view of a lens of a focusing apparatus for optical low coherence pitch measurement of the present invention;

FIG. 4 is a side view of a focusing apparatus for optical low coherence gap measurement of the present invention;

FIG. 5 is a perspective view of an upper cover of a holder of a focusing apparatus for optical low coherence interval measurement according to the present invention;

FIG. 6 is a perspective view of a sleeve of a focusing apparatus for optical low coherence gap measurement of the present invention;

FIG. 7 is a perspective view of a lens barrel of a focusing apparatus for optical low coherence interval measurement according to the present invention;

FIG. 8a is a first optical path structure diagram of a focusing lens assembly with a focal length of 200mm according to the present invention;

FIG. 8b is a diagram of a second optical path structure with a focal length of 500mm for a focusing lens assembly according to the present invention;

FIG. 8c is a diagram of a second optical path structure with a focal length of 1000mm for a focusing lens assembly according to the present invention;

FIG. 8d is a diagram of a fourth optical path structure in which the focal length of the focusing lens assembly of the present invention is infinite;

reference numerals:

100. the focusing mechanism comprises a focusing body, 101, a motor, 102, a first gear, 103, a second gear, 1031, a gear pressing ring, 1032, a protrusion, 104, a guide post, 105, a sleeve, 1051, a spiral groove, 1052, a groove, 106, a lens barrel, 1061, a first lens barrel, 1062, a second lens barrel, 1063, a first through groove, 1064, a lens barrel spacer, 107, a base, 108, an optical fiber fixing barrel, 109, an optical fiber joint, 1101, a lens fixing seat, 1102, a fixing seat upper cover, 1103, a fixing part, 1104, a clamping part, 111, a trimming pad, 112, a motor seat, 1131, a first cemented lens, 1132, a second cemented lens, 1133, a third cemented lens, 114, a movable barrel, 117, a spacer ring, 118, an inner hexagonal screw, 119, a 200mm focusing optical path, 120, 500mm focusing optical path, 121, 1000mm focusing optical path, 122, and an infinite focusing optical path.

Detailed Description

The present invention will be further described with reference to the accompanying drawings and the detailed description, and it should be noted that any combination of the embodiments or technical features described below can be used to form a new embodiment without conflict.

The invention provides a focusing device for measuring an optical low coherence interval, which comprises a focusing body 100, wherein the focusing body 100 comprises a driving assembly, a transmission assembly, a lens barrel 106, a guide structure and a sleeve 105, the driving assembly is used for driving the transmission assembly to drive the sleeve 105 to rotate, and the sleeve 105 is arranged on the outer wall of the lens barrel 106; a movable cylinder 114 is arranged in the lens barrel 106, and one end of the guide structure is fixedly arranged on the movable cylinder 114; the other end of the guiding structure is connected with the lens barrel 106 and the sleeve 105; the driving assembly drives the transmission assembly to drive the sleeve 105 to rotate, and the guiding structure drives the movable barrel 114 and the cemented lens therein to move along the axial direction of the lens barrel 106 under the driving of the sleeve 105, so as to adjust the focal length. In one embodiment, the driving component is preferably a motor 101, and the transmission component is preferably a gear transmission, although the driving component and the transmission component are not limited to the motor and the gear transmission. A plurality of cemented lenses are fixedly mounted in the lens barrel 106, and focusing is performed by changing the distance between the cemented lenses. Preferably, the present embodiment includes three groups of cemented lenses, each group of cemented lens includes two lenses, and the two lenses are glued together, so that the combination of the two lenses achieves a good achromatization effect. The first cemented lens 1131 is fixedly installed in the movable barrel 114, two groups of cemented lenses, namely, the second cemented lens 1132 and the third cemented lens 1133 are installed in the other end of the lens barrel 106, namely, the second lens barrel 1062 referred to hereinafter, focusing is performed through movement of the cemented lenses in the movable barrel 114, the focal length of the lenses can be adjusted in a large range, and it is ensured that the focal point of the light beam moves to a required position. In addition, the two sides of the three groups of cemented lenses are fixed in position by a pressing ring or spacer 117 to avoid movement, and the spacer 117 is included between the second cemented lens 1132 and the third cemented lens 1133. In this embodiment, the driving assembly drives the transmission assembly to drive the lens barrel 106, and the lens barrel 106 drives the guiding structure to drive the movable barrel 114 to move, so that the distance between the cemented lenses changes.

In one embodiment, the guiding structure includes a spiral groove 1051, a first through groove 1063, and a guiding post 104, the spiral groove 104 is located on the wall of the sleeve 105, the first through groove 1063 is located on the wall of the lens barrel 106 and extends along the axial direction thereof, one end of the guiding post 104 is fixedly mounted on the movable barrel 114, and the other end of the guiding post 104 passes through the first through groove 106 and moves along the spiral groove 1051. In this embodiment, when the motor 101 drives the gear to rotate, and the gear drives the sleeve 105 to rotate, the sleeve 105 drives the guiding column 104 to move along the spiral groove 1051 and simultaneously move along the first through groove 1063 of the lens barrel 106, so as to drive the movable barrel 114 and the cemented lens therein to move along the first through groove 1063. By adjusting the motor 101 to control the moving distance of the cemented lens, the focal length of the lens can be adjusted in a large range, ensuring that the focal point of the light beam moves to a desired position.

Specifically, the first through groove 1063 forms a path on the wall of the lens barrel 106 parallel to the axis of the lens barrel 106. The first through slot 1063 on the lens barrel 106 is in a rounded rectangle shape, and the long side of the rounded rectangle is parallel to the axis of the lens barrel 106, i.e. the movable barrel 114 moves along the axis direction of the lens barrel 106. The movable cylinder 114 comprises a through hole which is a threaded hole, the outer surface of one end of the guide post 104 is provided with a thread matched with the threaded hole, and the guide post 104 is fixed on the movable cylinder 114 through the thread. The diameter of the part of the guide post 104 fixed in the through hole is smaller than that of the other part of the guide post 104, so that the guide post 104 is fixed on the movable cylinder 114, and looseness is avoided during use.

In one embodiment, the focusing body 100 includes a motor 101, a first gear 102, a second gear 103, a lens barrel 106, a cemented lens group, and a guide post 104, the first gear 103 is mounted on the motor 101, the first gear 102 engages the second gear 103; the inner wall of the second gear 103 comprises a plurality of bulges 1032, a sleeve 105 is arranged between the second gear 103 and the lens barrel 106, and the sleeve 105 comprises a groove 1052 matched with the plurality of bulges 1032 and a spiral groove 1051; a movable cylinder 114 is installed inside the lens barrel 106, and the outer wall of the movable cylinder 114 includes a through hole (not shown) matching the guide post 104; the outer wall of the lens barrel 106 includes a first through slot 1063, one end of the guide post 104 is fixedly mounted in the through hole of the movable barrel 114 and passes through the first through slot 1063, and the other end of the guide post 104 passes through and protrudes out of the spiral slot 1051; the cemented lens group includes several cemented lenses, and a first cemented lens 1131 is fixedly mounted inside the movable barrel.

The motor 101 drives the first gear 102, the first gear 102 drives the second gear 103 to rotate, the second gear 103 drives the sleeve 105 to rotate, and the guide post 104 is driven by the sleeve 105 to move so that the movable cylinder 114 and the cemented lens move along the first through slot 1063. In one embodiment, the focusing body 100 includes a lens and a motor 101, the lens includes a lens barrel 106, a cemented lens group, a fiber joint 109, a fiber fixing barrel 108, and a guide post 104. The motor 101 and the motor base 112, the lens fixing base 1101 and the base 107, the lens fixing base 1101 and the fixing base upper cover 1102, and the optical fiber fixing cylinder 108 and the lens barrel 106 are all fixed through a plurality of socket head cap screws 118. The diameter of the second gear 103 is larger than that of the first gear 102, and a plurality of protrusions 1032 on the inner wall of the second gear 103 are in interference fit with the grooves 1052 on the sleeve, so that the sleeve 105 is driven to rotate together when the second gear 103 rotates; a gear pressing ring 1031 is mounted on the outer side of the second gear 103. Guide post 104 connects sleeve 105, barrel 106 and movable barrel 114,

in one embodiment, the motor 101 is a pulse stepping motor having a null reset function, and the moving distance of the first cemented lens 1131 is controlled by setting the number of pulses of the pulse stepping motor 101. In this embodiment, the stepping motor 101 is of an impulse type, for example, it is preferable that the stepping motor can achieve 10000 impulse revolutions, the number of teeth of the first gear 102, which is a pinion on the motor shaft, is 21, and the number of teeth of the second gear 103, which is a gearwheel on the lens, is 32, and the pitch of the spiral groove 1051 for machining the sleeve of the lens is preferably 7mm, that is, the moving distance of the cemented mirror corresponding to each impulse is 7/32 × 21/10000 — 0.00046 mm. The pulse stepping motor in the example is a stepping motor of an east motor, and can realize 1000/10000 pulse two gears with zero reset setting. In this embodiment, the number of teeth of the first gear 102 and the second gear 103 and the pitch of the spiral groove 1051 can be set as required, and the assembly and adjustment are easy.

In one embodiment, the focusing body 100 further includes an optical fiber fixing cylinder 108 and an optical fiber connector 109, the optical fiber fixing cylinder 108 is fixedly connected to the lens barrel 106, and the optical fiber is fixed in the optical fiber fixing cylinder 108 through the optical fiber connector 109. In this embodiment, the optical fiber is fixed in the optical fiber fixing cylinder 108 through the optical fiber connector 109, and the optical fiber fixing cylinder 108 is over-fitted with the lens barrel 106, and is fixed by a set screw after the position of the optical fiber is adjusted. The standard optical fiber connector can be used in different optical fiber systems, and utilization rate is improved.

In one embodiment, the lens barrel 106 includes a first barrel 1061 and a second barrel 1062, the first barrel 1061 and the second barrel 1062 are integrally formed, the movable barrel 114 is installed in the first barrel 1061, the first barrel 1061 is close to the second gear 103, and the movable barrel 114 moves in the first barrel 1061; several cemented lenses are fixedly mounted in the second barrel 1062 close to the fiber stub 109. In this embodiment, the lens barrel 106 is divided into a first lens barrel 1061 and a second lens barrel 1062 by the lens barrel partition 1064, the first lens barrel 1061 and the second lens barrel 1062 are integrally formed, the movable cylinder 114 is installed inside the first lens barrel 1061, the movable cylinder 114 is driven to move by the guide post 104, and the movable cylinder 114 is limited by the lens barrel partition 1064 and the guide post 104 and can only move in the first lens barrel 1061. Several cemented lenses are fixedly mounted in a second barrel 1062, the second barrel 1062 being close to the fiber stub 109. Preferably, the first and second electrodes are formed of a metal,

in one embodiment, the focusing body 100 further includes a lens fixing seat 1101, a fixing seat upper cover 1102 and a base 107, the lens fixing seat 1101 is fixedly installed on the base 107, the lens fixing seat 1101 includes a notch matching with the outer wall of the lens barrel 106, and the lens barrel 106 is fixedly installed on the lens fixing seat 1101 through the lens fixing seat 1101 upper cover; the holder upper cover includes an engaging portion 1104 and a fixing portion 1103, the engaging portion 1104 is used for matching with an outer wall of the lens barrel 106, and the fixing portion 1103 is used for fixing the lens barrel 106 on the lens holder 1101. The focusing body 100 further comprises a motor base 112 and a trimming pad 111, the motor base 112 fixes the motor 101 on the base 107, the trimming pad 111 is connected with the motor base 112, and the trimming pad 111 is used for adjusting the meshing accuracy of the first gear 102 and the second gear 103. In this embodiment, the motor 101 is fixed on the base 107 through the motor base 112, and the base 107 includes a plurality of fixing holes for fixedly connecting the focusing body 100 with other devices. The motor base 112 is also fixedly connected with a dressing pad 111, and the dressing pad 111 can improve the meshing precision of the first gear 102 and the second gear 103 by adjusting the height of the dressing pad 111. As shown in fig. 5, the lens holder 1101 is fixed to the chassis 107, the lens is placed on the lens holder 1101 and fixed by the holder upper cover 1102, the holder upper cover 1102 includes an engaging portion 1104 and a fixing portion 1103, the engaging portion 1104 is matched with the outer wall of the lens, the engaging portion 1104 and the fixing portion 1103 are integrally formed, and the fixing portion 1103 is fixed to the holder by an allen screw.

Generally, the material of the sleeve 105, the lens barrel 106, the pressing ring, the spacer 117 and the base 107 is duralumin alloy, and the material of the guide post 104 is martensitic stainless steel.

Optical path description, as shown in FIGS. 8a-8 d:

in order to better collect the reflected light signals of each optical surface of a sample to be measured, the distance measuring system is provided with a group of focusing modules. Before a sample to be measured is measured, the focusing amount of the focusing module is controlled according to the design parameters of the sample to be measured, so that the measuring light is focused near the last optical surface of the sample to be measured. The optical main design parameters of the focusing module comprise: the design wavelength is 1.21-1.41 μm and 0.65 μm, and the focusing range is 200 mm-infinity. The focusing lens consists of three groups of double cemented lenses, and is designed to cover two wave bands, namely 1.21-1.41 μm and 0.65 μm, and the visible indication light source is an LD light source with 0.65 μm. The first optical path 8a is set to a focusing distance of 200mm, the second optical path 8b is set to a focusing distance of 500mm, the third optical path 8c is set to a focusing distance of 1000mm, and the fourth optical path 8d is set to a focusing distance of infinity.

The invention discloses a focusing device for optical low coherence interval measurement. The movement distance of the cemented lens is controlled by the number of pulses input by the pulse type stepping motor, the focal length of the lens can be adjusted in a large range, and the measurement light is conveniently focused near the optical surface of a sample to be measured during optical low-coherence distance measurement. The standard optical fiber connector can be used in different optical fiber systems, and utilization rate is improved. The device realizes the collimation or the focusing of a point light source, and has the advantages of simple structure, easy assembly and adjustment and high adjustment resolution.

The foregoing is merely a preferred embodiment of the invention and is not intended to limit the invention in any manner; those skilled in the art can readily practice the invention as shown and described in the drawings and detailed description herein; however, those skilled in the art should appreciate that they can readily use the disclosed conception and specific embodiments as a basis for designing or modifying other structures for carrying out the same purposes of the present invention without departing from the scope of the invention as defined by the appended claims; meanwhile, any changes, modifications, and evolutions of the equivalent changes of the above embodiments according to the actual techniques of the present invention are still within the protection scope of the technical solution of the present invention.