Adjustment device of light homogenizing rod and illumination light path applied to semiconductor detection

Abstract

The invention relates to the technical field of semiconductor detection, in particular to an assembling and adjusting device of a light uniformizing rod and an illumination light path applied to semiconductor detection.The assembling and adjusting device comprises an upper clamping piece and a lower clamping piece which are asymmetrically designed, and the lower clamping piece supports the lower surface of the light uniformizing rod through an arc-shaped protruding point at the bottom of a containing groove; the upper surface of the dodging rod is supported by the pressure spring, the semispherical bulge is arranged at the midpoint of the pressure spring, and the dodging rod is clamped by the six contact points, so that the contact area between the clamping piece and the dodging rod is effectively reduced; after the upper clamping piece and the lower clamping piece are buckled, the upper clamping piece and the lower clamping piece are installed on the five-dimensional adjusting frame, the five-dimensional adjusting frame is installed on the one-dimensional displacement table, and multi-degree-of-freedom displacement decoupling of the dodging rod is achieved through the five-dimensional adjusting frame and the one-dimensional displacement table. When the adjusting device is used for clamping the dodging rod, the high clamping stability is achieved, meanwhile, damage to the dodging rod caused by rigid clamping is avoided, the good heat dissipation effect is achieved, and when the adjusting device is applied to an illumination light path, the light path stability and the adjusting flexibility can be improved.

Description

Technical Field

[0001] The invention relates to the technical field of semiconductor detection, and specifically provides an adjustment device for a light homogenizing rod and an illumination light path applied to semiconductor detection. Background Art

[0002] In semiconductor inspection lighting systems, the role of the homogenizer is crucial. It is used to homogenize the light coupled into it to ensure the uniformity of the light source illumination. Since the semiconductor inspection field has high requirements for the stability of the homogenizer, the homogenizer must be accurately placed in the critical illumination light path, and its end face acts as a light source as part of the designed light path. When building the light path, in order to ensure that each optical component can accurately meet the requirements of the light path design, the position and posture of the homogenizer must be precisely adjusted.

[0003] However, the clamping stability of the homogenizer rod in the general lighting optical path is often not enough to meet the high requirements of semiconductor detection, and the homogenizer rod itself is fragile, which brings challenges to its fixation and adjustment. In the process of fixing the homogenizer rod, two requirements need to be met at the same time: one is to ensure that the clamping is tight to ensure the stability of the homogenizer rod in the lighting system; the other is to avoid damage to the homogenizer rod. Since the homogenizer rod has the fragile property, it is easy to break or be damaged due to excessive clamping or improper operation. In addition, after fixing the homogenizer rod, the traditional clamping device often couples the up and down, left and right, front and back translation and tilt adjustment of the homogenizer rod. Once the position or posture of one direction needs to be adjusted, it may affect the settings of other directions, making the adjustment process complicated and difficult.

[0004] The conventional clamping device usually consists of two symmetrical clamping parts, which fully wrap the light homogenizing rod or clamp it at one end of the light homogenizing rod. The fully wrapped method is not conducive to the heat dissipation of the light homogenizing rod; while the method of clamping at one end is difficult to achieve stable clamping, and the stress at the contact position between the clamping device and the light homogenizing rod is large, and the light homogenizing rod is easily damaged. In addition, the outer surface of the existing clamping device is smooth and cylindrical, and the fixing stability of the adjustment frame and the clamping device is poor, which further reduces the stability of the light homogenizing rod.

[0005] Therefore, it is necessary to develop a new homogenizer rod installation and adjustment device that can ensure the clamping and tightening while avoiding damage to the homogenizer rod, can achieve high-stability clamping of the homogenizer rod, and can realize independent adjustment in all directions, so as to quickly and accurately complete the position and posture adjustment of the homogenizer rod, and improve the efficiency and accuracy of the lighting system construction. Summary of the invention

[0006] In order to solve the above problems, the present invention provides an adjustment device for a homogenizing rod and an illumination optical path. The homogenizing rod is fixed by two asymmetric clamping parts, which improves the heat dissipation effect, and optimizes the clamping structure to achieve not only elastic clamping but also reduced contact points between the clamping parts and the homogenizing rod. It has high clamping stability and avoids damage to the homogenizing rod caused by rigid clamping. In addition, multi-dimensional adjustment decoupling is achieved through a five-dimensional adjustment frame and a one-dimensional translation stage, thereby improving the adjustment accuracy of the homogenizing rod.

[0007] The device for assembling and adjusting a light homogenizing rod provided by the present invention comprises: A lower clamping member, on which a receiving groove for the light homogenizing rod is formed, and a plurality of supporting structures are provided at the bottom of the receiving groove, wherein the supporting structures have at least two arc-shaped protruding points for abutting against the light homogenizing rod; an upper clamping member engaged with the lower clamping member; The compression spring has a hemispherical protrusion at the midpoint of its side surface. The compression springs on both sides of the hemispherical protrusion are elastic arm structures, and the outer ends of the elastic arm structures are fixed on the lower clamping members on both sides of the supporting structure.

[0008] Preferably, the outer surfaces of the lower clamping member and the upper clamping member are cylindrical surfaces with stepped protrusions.

[0009] Preferably, two supporting structures are provided at the bottom of the receiving tank.

[0010] Preferably, the distance between the two supporting structures is greater than the length of the upper clamping member, and the upper clamping member is arranged between the two supporting structures.

[0011] Preferably, the mid-vertical plane of the above clamping member axis is a symmetrical plane, and the stepped protrusions on its outer surface are asymmetrical. Preferably, the perpendicular midplane of the lower clamping member axis is a symmetric plane, and the stepped protrusions on its outer surface are asymmetric.

[0012] Preferably, a plurality of depressions with arc-shaped cross-sections are formed at the upper end of the support structure, and arc-shaped protrusions for abutting against the light homogenizing rod are formed between adjacent depressions.

[0013] Preferably, the length of the lower clamping member is greater than or equal to the length of the light homogenizing rod.

[0014] Preferably, the elastic arm structure of the compression spring is Z-shaped, and elastic potential energy perpendicular to the side of the compression spring is stored by stretching the Z-shaped elastic arm structure.

[0015] Preferably, a threaded through hole is opened at the midpoint of the compression spring, and the rear end of the hemispherical protrusion is connected to a threaded column matched with the threaded through hole. The hemispherical protrusion is fixed and the height of the hemispherical protrusion is adjusted by the matched threaded column and the threaded through hole.

[0016] Preferably, it also includes a five-dimensional adjustment frame and a one-dimensional displacement platform, the combination of the lower clamping member and the upper clamping member is fixed in the installation frame of the five-dimensional adjustment frame, the side surfaces of the installation frame are respectively provided with knobs for driving the combination to move in the Z direction and the Y direction, and the end surface of the installation frame is provided with a tilt adjustment knob for driving the combination to rotate; the five-dimensional adjustment frame is arranged on the one-dimensional displacement platform, and the one-dimensional displacement platform is used to drive the five-dimensional adjustment frame to move in the X direction.

[0017] An illumination light path adopts a light homogenizing rod installation and adjustment device to fix the light homogenizing rod to realize light path propagation and adjustment.

[0018] Compared with the prior art, the present invention can achieve the following beneficial effects: The upper and lower clamping parts of the adjustment device of the present invention adopt an asymmetric clamping design. The lower clamping part half-wraps and supports the light homogenizing rod, which has a good supporting effect on the light homogenizing rod as a whole, avoiding damage to the light homogenizing rod caused by the position or posture adjustment of the front and rear optical elements or structural parts; the upper clamping part only partially wraps the light homogenizing rod, and the input coupling end face and the output end face of the light homogenizing rod are directly visible, which can not only achieve stable control of the light homogenizing rod, but also improve the heat dissipation effect of the light homogenizing rod and avoid the deformation of the light homogenizing rod due to heat. In addition, left and right asymmetric stepped protrusions are designed on the outer surfaces of the upper and lower clamping parts. The asymmetric stepped protrusions can make the upper and lower clamping parts only install from one side of the adjustment frame after buckling. The stepped protrusions not only play the role of installation limit, but also can avoid the displacement of the upper and lower clamping parts along the opening axis of the installation frame, further improving the stability of the light homogenizing rod.

[0019] The present invention has specially designed the contact points between the clamping piece and the homogenizing rod. Two front and rear supporting structures are arranged on the lower clamping piece, each supporting structure has two arc-shaped protrusions, and the lower clamping piece and the homogenizing rod have only four contact points, which greatly reduces the contact area between the homogenizing rod and the clamping piece; the upper surface of the homogenizing rod is fixed by a hemispherical protrusion arranged in the middle of the compression spring, and each compression spring has only one point in contact with the homogenizing rod. The elastic potential energy of the compression spring is used to elastically clamp the homogenizing rod. The compression spring will not damage the homogenizing rod while pressing the homogenizing rod, thereby avoiding the disadvantages of traditional rigid clamping. In addition, the height of the hemispherical protrusion on the compression spring is adjustable, and then the pressure of the compression spring on the homogenizing rod can be adjusted according to the pressure requirement or to adapt to homogenizing rods of different sizes, which has high flexibility in the installation and adjustment process.

[0020] The present invention uses a five-dimensional adjustment frame and a one-dimensional translation stage to perform motion decoupling on the adjustment device of the homogenizing rod, which can ensure that after the homogenizing rod is fixed by the clamping part, the up and down, left and right, front and back translation and tilt are adjusted separately, avoiding mutual interference in the adjustment process of different degrees of freedom and reducing the difficulty of adjustment. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1is a structural diagram of a light homogenizing rod installation and adjustment device provided according to an embodiment of the present invention; Figure 2 is a top view of a light homogenizing rod mounting and adjusting device provided according to an embodiment of the present invention; Figure 3 is a partial cross-sectional enlarged view of the light homogenizing rod installation and adjustment device provided according to an embodiment of the present invention; Figure 4 is a structural diagram of a lower clamping member provided according to an embodiment of the present invention; Figure 5 is a detailed diagram of the clamping of the light homogenizing rod by the lower clamping member and the upper clamping member according to an embodiment of the present invention; Figure 6 is a structural diagram of a compression spring provided according to an embodiment of the present invention.

[0022] Reference numerals include: Base plate 1, one-dimensional displacement stage 2, five-dimensional adjustment frame 3, light homogenizing rod 4, lower clamping piece 5, upper clamping piece 6, compression spring 7, compression ring 8; Locking screw 21, Y-axis displacement knob 31, Z-axis displacement knob 32, tilt adjustment knob 33; Accommodating groove 51, supporting structure 52; Hemispherical protrusion 71 and elastic arm structure 72. DETAILED DESCRIPTION

[0023] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In the following description, the same modules are represented by the same reference numerals. In the case of the same reference numerals, their names and functions are also the same. Therefore, the detailed description thereof will not be repeated.

[0024] It should be noted that the directions or positional relationships indicated by terms such as “upper”, “lower”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside” and “outside” are based on the directions or positional relationships shown in the accompanying drawings and are only for the convenience of describing the present invention and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, they should not be understood as limiting the present invention.

[0025] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and do not constitute a limitation of the present invention.

[0026] See also Figure 1 and Figure 2In one embodiment of the present invention, a device for adjusting a light homogenizing rod is provided, comprising: a one-dimensional displacement stage 2, a five-dimensional adjustment frame 3, a lower clamping member 5, an upper clamping member 6 and a compression spring 7, wherein, see Figure 3 The lower clamping member 5 and the upper clamping member 6 are used to clamp the homogenizing rod 4. The combination of the lower clamping member 5 and the upper clamping member 6 is fixed in the installation frame of the five-dimensional adjustment frame 3 by the pressure ring 8. The homogenizing rod 4 is driven by the five-dimensional adjustment frame 3 to realize Y-direction displacement, Z-direction displacement and tilt rotation. Specifically, a Z-direction displacement knob 32 for driving the homogenizing rod 4 to move up and down is provided on the upper surface of the installation frame; a Y-direction displacement knob 31 for driving the homogenizing rod 4 to move left and right is provided on the side surface of the installation frame; and three tilt adjustment knobs 33 are provided on the front surface of the installation frame. By combining and adjusting the tilt adjustment knobs 33, the homogenizing rod 4 can be driven to tilt and rotate, and the up and down displacement, left and right displacement and tilt rotation of the homogenizing rod 4 can be realized through the five-dimensional adjustment frame 3.

[0027] The five-dimensional adjustment frame 3 is fixed on the one-dimensional displacement stage 2, and the one-dimensional displacement stage 2 is set on the bottom plate 1. The regulator of the one-dimensional displacement stage 2 can drive the five-dimensional adjustment frame 3 and the homogenizing rod 4 to move forward and backward, that is, the displacement in the X direction, and after the adjustment is in place, the position can be locked by the locking screw 21 of the one-dimensional displacement stage 2 to prevent the homogenizing rod 4 from shifting in the optical path. The embodiment of the present invention can independently adjust the homogenizing rod 4 with multiple degrees of freedom through the one-dimensional displacement stage 2 and the five-dimensional adjustment frame 3, decouple the up-down, left-right, and front-back translation and tilt, and reduce the difficulty of adjusting the homogenizing rod 4 in the illumination optical path.

[0028] See also Figure 4 and Figure 5 The lower clamping member 5 is a semi-cylindrical structure, and its outer side surface is a cylindrical surface with a stepped protrusion. The design of the stepped protrusion is mainly used to adapt the installation requirements of the lower clamping member 5 in the installation frame of the five-dimensional adjustment frame 3. The lower clamping member 5 has a receiving groove 51 adapted to the side of the light homogenizing rod 4 at the position of the section axis. Two supporting structures 52 are provided at the bottom of the receiving groove 51. The supporting structure 52 is arranged along the width direction of the receiving groove 51. The upper end of the supporting structure 52 has three concave depressions with arc-shaped cross sections. The spacing between the three concave depressions is equal, and arc-shaped protrusions are formed between adjacent arc-shaped concave depressions. It can be understood that when the homogenizing rod 4 is clamped and installed, each supporting structure 52 supports the homogenizing rod 4 through two arc-shaped protrusions, and the arc-shaped recess design reduces the contact area between the lower clamping member 5 and the homogenizing rod 4. The lower clamping member 5 has a total of 4 points in contact with the surface of the homogenizing rod 4, and the arc-shaped recess can also improve the heat dissipation efficiency of the homogenizing rod 4, avoiding the homogenizing rod 4 in the clamped part from being unable to achieve effective heat dissipation, causing it to soften due to heat, and avoiding the problem of light angle deviation in the homogenizing rod 4.

[0029] As a preferred embodiment, the length of the lower clamping member 5 is equal to or slightly greater than the length of the homogenizing rod 4, ensuring that the homogenizing rod 4 can be completely located in the accommodating groove 51 of the lower clamping member 5. The homogenizing rod 4 is protected by the lower clamping member 5 to prevent the homogenizing rod 4 from being damaged by collision during the adjustment of the homogenizing rod 4.

[0030] The upper clamping member 6 and the lower clamping member 5 adopt an asymmetric clamping design, that is, the upper clamping member 6 and the lower clamping member 5 are asymmetric along the contact surface between the two. Specifically, the length of the upper clamping member 6 is less than the spacing between the two supporting structures 52 of the lower clamping member 5. The upper clamping member 6 is connected to the lower clamping member 5 by screws, and the connection position is between the two supporting structures 52. The asymmetric clamping design can ensure that the lower clamping member 5 can provide sufficient protection for the homogenizing rod 4, and the upper clamping member 6 only partially wraps the upper surface of the homogenizing rod 4. The input coupling end face and the output end face of the homogenizing rod 4 are directly exposed to the air. Since the laser spot size of the input coupling end face of the homogenizing rod is small and the energy density is high, direct exposure to the air can increase the heat dissipation effect and prevent the homogenizing rod from being deformed by heat. Compared with the existing completely wrapped fixing method, the fixing method of the embodiment of the present invention has a better heat dissipation effect and will not affect the protective effect of the adjustment device on the homogenizing rod 4; compared with the method of only clamping one end of the homogenizing rod 4, the fixing method of the embodiment of the present invention has the advantages of better fixing stability and better protection effect on the homogenizing rod 4.

[0031] As a preferred embodiment, the outer surfaces of the lower clamping member 5 and the upper clamping member 6 are cylindrical surfaces with multiple sections of stepped protrusions. Along the axial direction of the lower clamping member 5, the mid-vertical plane of the axis of the lower clamping member 5 is the symmetric plane, and the stepped protrusions on the lower clamping member 5 are designed to be left-right asymmetrical. This design is mainly convenient for fixing the lower clamping member 5 and the upper clamping member 6 in the installation frame of the five-dimensional adjustment frame 3. It can be understood that the outer diameters of the stepped protrusions on the left and right sides of the lower clamping member 5 are different, and the outer diameter of one of the stepped protrusions on one side is preferably designed to be larger than the inner diameter of the installation frame, while the outer diameters of the stepped protrusions on the other side are all smaller than the inner diameter of the installation frame. After the lower clamping member 5 and the upper clamping member 6 are buckled together, the side with the smaller outer diameter of the protrusion can be extended into the installation frame until the larger outer diameter of the protrusion clamps the lower clamping member 5. This design can improve the installation stability of the lower clamping member 5 and the upper clamping member 6 in the installation frame, avoid the displacement of the lower clamping member 5 and the upper clamping member 6 along the opening axis of the installation frame, further improve the stability of the light homogenizing rod in the optical path, and avoid the slight displacement of the light homogenizing rod relative to the clamping device during the posture adjustment process. Similarly, the stepped protrusion on the upper clamping member 6 can also adopt the asymmetric design of the following clamping member 5. The specific design form will not be repeated here. Please refer to the design description of the lower clamping member 5, which also has the effect of improving the stability of the light homogenizing rod.

[0032] See also Figure 6The upper surface of the light homogenizing rod 4 is elastically fixed by a compression spring 7. Two identical compression springs 7 are respectively provided on both sides of the upper clamping member 6. The compression spring 7 is in the form of a strip of metal sheet. Through holes are respectively provided at both ends of the compression spring 7 along the length direction of the compression spring 7. The compression spring 7 is respectively fixed to the lower clamping member 5 on both sides of the support structure 52 by bolts. Two groups of interlaced slots are provided along the width direction of the compression spring 7 to form a Z-shaped elastic arm structure 72. The compression spring 7 realizes elastic deformation and stores elastic potential energy by stretching the elastic arm structure 72. In addition, a threaded hole is provided at the center of the compression spring 7 for fixing the hemispherical protrusion 71. A threaded column matched with the threaded hole is provided at the rear end of the hemispherical protrusion 71. The hemispherical protrusion 71 is fixed at the midpoint of the compression spring 7 by the cooperation of the threaded hole and the threaded column. When the light homogenizing rod 4 is clamped, the lower clamping member 5 supports the lower surface of the light homogenizing rod 4 through the four contact points of the supporting structure 52, and the upper surface of the light homogenizing rod 4 is elastically abutted through the hemispherical protrusion 71 on the compression spring 7. Therefore, when the light homogenizing rod 4 is fixed by the adjustment device of the embodiment of the present invention, there are 6 contact points, which greatly reduces the contact area with the light homogenizing rod 4. The elastic fixation by the compression spring 7 can not only stably clamp the light homogenizing rod 4, but also avoid the problem that the local stress of the light homogenizing rod 4 is too large due to rigid clamping, thereby causing the light homogenizing rod 4 to break.

[0033] As a preferred embodiment, by screwing in or out the threaded column of the hemispherical protrusion 71, the protrusion height of the hemispherical protrusion 71 on the compression spring 7 can be adjusted, the elastic deformation degree of the compression spring 7 can be changed, and then the elastic force provided by the compression spring 7 for fixing the light homogenizing rod 4 can be changed. By changing the protrusion height of the hemispherical protrusion 71, light homogenizing rods 4 of different sizes can be adapted and fixed; or the pressure of the compression spring 7 on the light homogenizing rod 4 can be adjusted to meet different fixing strength requirements. The embodiment of the present invention uses the compression spring 7 to elastically clamp the light homogenizing rod 4, which not only reduces the probability of damage to the light homogenizing rod 4, but also improves the clamping flexibility of the light homogenizing rod 4.

[0034] The adjustment device for the homogenizing rod of the embodiment of the present invention can be used in the illumination light path to fix the homogenizing rod 4 in the light path. The coupling input end of the homogenizing rod 4 is connected to the front-end optical system, and the output end of the homogenizing rod 4 is connected to the rear-end optical system. The homogenizing rod 4 can be fixed by the adjustment device to achieve stable propagation of the light path, or the position of the homogenizing rod 4 in the light path can be adjusted to achieve adjustment of the light path.

[0035] Although the embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and cannot be understood as limiting the present invention. Those skilled in the art may change, modify, replace and modify the above embodiments within the scope of the present invention.

[0036] The above specific implementations of the present invention do not constitute a limitation on the protection scope of the present invention. Any other corresponding changes and modifications made based on the technical concept of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A device for adjusting a light homogenizing rod, characterized in that: include: A lower clamping member, on which a receiving groove for the light homogenizing rod is formed, and a plurality of supporting structures are provided at the bottom of the receiving groove, wherein the supporting structures have at least two arc-shaped protruding points for abutting against the light homogenizing rod; an upper clamping member buckled with the lower clamping member; The compression spring has a hemispherical protrusion at the midpoint of its side surface. The compression springs on both sides of the hemispherical protrusion are elastic arm structures, and the outer ends of the elastic arm structures are fixed on the lower clamping members on both sides of the supporting structure.

2. The light homogenizing rod installation and adjustment device according to claim 1, characterized in that: The outer surfaces of the lower clamping member and the upper clamping member are cylindrical surfaces with stepped protrusions.

3. The light homogenizing rod installation and adjustment device according to claim 1, characterized in that: Two supporting structures are provided at the bottom of the containing tank.

4. The light homogenizing rod installation and adjustment device according to claim 3, characterized in that: The distance between the two supporting structures is greater than the length of the upper clamping member, and the upper clamping member is arranged between the two supporting structures.

5. The light homogenizing rod installation and adjustment device according to claim 2, characterized in that: The mid-vertical plane of the axis of the upper clamping piece is taken as a symmetry plane, and the stepped protrusions on the outer surface thereof are asymmetric.

6. The light homogenizing rod adjustment device according to claim 2 or 5, characterized in that: The mid-vertical plane of the axis of the lower clamping piece is taken as a symmetry plane, and the stepped protrusions on the outer surface thereof are asymmetric.

7. The light homogenizing rod installation and adjustment device according to claim 1, characterized in that: The upper end of the support structure is provided with a plurality of depressions with arc-shaped cross sections, and arc-shaped protrusions for contacting with the light homogenizing rod are formed between adjacent depressions.

8. The light homogenizing rod installation and adjustment device according to claim 1, characterized in that: The length of the lower clamping member is greater than or equal to the length of the light homogenizing rod.

9. The light homogenizing rod installation and adjustment device according to claim 1, characterized in that: The elastic arm structure of the compression spring is Z-shaped, and elastic potential energy perpendicular to the side surface of the compression spring is stored by stretching the Z-shaped elastic arm structure.

10. The light homogenizing rod installation and adjustment device according to claim 9, characterized in that: A threaded through hole is opened at the midpoint of the compression spring, and a threaded column matched with the threaded through hole is connected to the rear end of the hemispherical protrusion. The hemispherical protrusion is fixed and its height is adjusted by the matched threaded column and the threaded through hole.

11. The light homogenizing rod installation and adjustment device according to claim 1, characterized in that: It also includes a five-dimensional adjustment frame and a one-dimensional displacement platform, wherein the combination of the lower clamping member and the upper clamping member is fixed in the installation frame of the five-dimensional adjustment frame, the side surfaces of the installation frame are respectively provided with knobs for driving the combination to perform displacement in the Z direction and the Y direction, and the end surface of the installation frame is provided with a tilt adjustment knob for driving the combination to rotate; the five-dimensional adjustment frame is arranged on the one-dimensional displacement platform, and the one-dimensional displacement platform is used to drive the five-dimensional adjustment frame to perform displacement in the X direction.

12. An illumination optical path used for semiconductor detection, characterized in that: The light homogenizing rod is fixed by using the light homogenizing rod mounting and adjusting device as claimed in any one of claims 1 to 11 to realize light path propagation and adjustment.

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