Method for generating square array synchronous spiral light beam
By superimposing the square array light vortex and spot, the synchronized square array spiral beam is formed by using plane wave interference, which solves the problem of the spiral beam being out of synchronization in the array, and realizes efficient application of material processing and particle manipulation.
Patent Information
- Application Number
- CN202510487100.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-18
- Publication Date
- 2025-08-01
AI Technical Summary
In the prior art, the adjacent vortex topological topology of the square array vortex beams have opposite symbols, which makes it impossible to form a helical structure in the same direction, and it is difficult to achieve complete synchronization of the helical beams in the array, which limits its effect in practical applications.
By superimposing the light vortex and spots of the square array, the interference of eight quasi-symmetric plane waves and four symmetric plane waves is used to form a square array spiral beam with synchronization characteristics, and the initial phase and amplitude ratio of the plane waves are adjusted to achieve synchronization of the spiral beam.
The spiral beam in the array has the same rotation direction synchronousness, and a spiral light field with the best contrast is obtained, with good controllability and flexibility, suitable for material processing and particle manipulation.
Smart Images
Figure CN120405940A_ABST
Abstract
Description
Technical Field
[0001] The present invention discloses a method for generating a square array synchronous spiral beam. Background Art
[0002] A spatial spiral beam is a beam with a special light intensity distribution in space, and its intensity distribution is in a spiral structure along the optical axis, which has certain application values in the fields of material processing, particle manipulation, and particle shunting.
[0003] In previous studies, there are two inherent limitations in the square array vortices formed by multi-beam interference: First, since the topological charge numbers of adjacent vortices have opposite signs, when they are superposed with an axial plane wave, a co-rotating spiral structure cannot be formed; Second, the unique phase distribution characteristics of the square array vortices make it difficult to achieve complete synchronization even for the spiral beams with the same rotation direction in the array. This limits the application of the array spatial spiral beam in actual production and life. Summary of the Invention
[0004] The present invention proposes a method for generating a square array synchronous spiral beam by superposing the optical vortices of a square array and the light spots of a square array.
[0005] The technical solution adopted by the present invention is as follows: The optical vortices of the square array are generated by the interference of eight quasi-symmetric plane waves, and the light spots of the square array are generated by the interference of four symmetric plane waves.
[0006] Fig. 1(a) shows a schematic diagram of the interference configuration of twelve plane waves. Fig. 1(b) shows the Fourier transverse wave vector components of the twelve plane waves. The twelve beams of light can be divided into eight outer quasi-symmetric plane waves and four inner symmetric plane waves. Assuming that the complex amplitudes of each outer and inner plane wave are A1 and A2 respectively. The transverse wave vectors of the outer quasi-symmetric plane waves and the inner symmetric plane waves are kr1 and kr2 respectively. The outer quasi-symmetric plane waves can be further divided into two groups that are mirror-symmetric with respect to the xoz plane. The four plane waves in each group are uniformly distributed with respect to the optical axis.
[0007] A method for generating a square array synchronous spiral beam disclosed by the present invention is applied to a material processing device for material processing.
[0008] A method for generating a square array synchronous spiral beam disclosed by the present invention is applied to a particle manipulation device.
[0009] Technical Effects of the Present Invention: The method for generating a square array of synchronous spiral beams provided by the present invention overcomes the problem of opposite spiral directions caused by opposite vortex topological charges in the prior art, and successfully realizes an array of spiral beams with synchronous characteristics, such that the spiral beams in the array have the same rotation direction; by precisely controlling the initial phases of the eight outer plane waves and the amplitude ratio of the inner and outer plane waves, a spiral light field with the optimal contrast can be obtained; the method of the present invention has good controllability and flexibility, and can selectively generate a single spiral array or a double spiral array, and can be widely applied to fields such as material processing and particle manipulation, and has important practical value. Description of the Drawings
[0010] Fig. 1(a) is a schematic diagram of the interference optical path of twelve plane waves.
[0011] Fig. 1(b) is a schematic diagram of the Fourier transverse wave vector components of twelve plane waves.
[0012] Fig. 2(a1) is a schematic diagram of the Fourier transverse wave vector components of the four inner plane waves with the same initial phase.
[0013] Fig. 2(b1) is the normalized intensity distribution of the light field formed by the interference of the four inner plane waves.
[0014] Fig. 2(c1) is the phase distribution of the light field formed by the interference of the four inner plane waves.
[0015] Fig. 2(a2) is a schematic diagram of the Fourier transverse wave vector components of the eight outer plane waves.
[0016] Fig. 2(b2) is the normalized intensity distribution of the light field formed by the interference of the eight outer plane waves shown in Fig. 2(a2).
[0017] Fig. 2(c2) is the phase distribution of the light field formed by the interference of the eight outer plane waves shown in Fig. 2(a2).
[0018] Figure 3 is a synchronous single spiral beam array formed by the interference of twelve beams of light in three-dimensional space.
[0019] Fig. 4(a1) is a schematic diagram of the Fourier transverse wave vector components of the four inner plane waves with the same initial phase.
[0020] Fig. 4(b1) is the normalized intensity distribution of the light field formed by the interference of the four inner plane waves.
[0021] Fig. ,4(c1) is the phase distribution of the light field formed by the interference of the four inner plane waves.
[0022] Fig. 4(a2) is a schematic diagram of the Fourier transverse wave vector components of the eight outer plane waves. 3]
[0023] Figure 4(b2) shows the normalized intensity distribution of the optical field formed by the interference of the outer eight plane waves shown in Figure 4(a2).
[0024] Figure 4(c2) shows the phase distribution of the optical field formed by the interference of the outer eight plane waves shown in Figure 4(a2).
[0025] Figure 5 It is a synchronous double-helical beam array formed by the interference of twelve beams of light in three-dimensional space. Detailed implementation mode
[0026] It should be noted that the following detailed description is exemplary and is intended to provide further illustration of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which this application belongs.
[0027] It should be noted that the terms used herein are only for describing specific implementation modes and are not intended to limit the exemplary implementation modes according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof; As described in the background art, the inventors found that in previous studies, due to the opposite topological charges of adjacent vortices in the square array vortices generated by multiple beams, the helix generated by the superposition of axial plane waves and square array vortices does not have the same directionality. And due to the phase distribution characteristics of the square array vortices themselves, the helical beams with the same rotation direction in the helical beam array are not completely synchronized. To solve the above technical problems, the present application proposes a method for obtaining a square array single-helical beam and a double-helical beam with synchronous characteristics by superimposing a non-diffracting square array vortex and a square array light spot. Embodiment 1
[0028] This embodiment provides a method for forming a square array single-helical beam with synchronous characteristics by superimposing a square array optical vortex and a square array light spot.
[0029] Specifically, the method includes the following steps: Step 1: Configure the parameters of the inner four plane waves and the outer eight plane waves. Among them, as shown in Figure 2(a1), the inner four plane waves have the same initial phase; as shown in Figure 2(a2), the relative initial phases of the outer eight plane waves are 0, π / 2, π, 3π / 2, π / 4, 3π / 4, 5π / 4, 7π / 4 in sequence; the wave vector components of the inner four plane waves and the outer eight plane waves satisfy: , the angle α shown in the figure = tan-1 (1 / 2), kr1 and kr2 are the transverse wave vector components of the outer eight plane waves and the inner four plane waves, respectively.
[0030] Step 2: Adjust the amplitude of the inner four plane waves to A2 and the amplitude of the outer eight plane waves to A1, such that the two satisfy the proportional relationship A2 ≈ 1.451A1.
[0031] Step 3: As shown in Figures 2(b1) and 2(c1), make the inner four plane waves interfere to form a square array light spot. Among them, Figure 2(b1) shows the normalized intensity distribution of the light field of the square array light spot, and Figure 2(c1) shows the phase distribution of the light field of the square array light spot. The phase difference between adjacent light spots is π.
[0032] Step 4: As shown in Figures 2(b2) and 2(c2), make the outer eight plane waves interfere to form a square vortex array with a topological charge of +1. Among them, Figure 2(b2) shows the normalized intensity distribution of the light field of the square vortex array with a topological charge of +1, and Figure 2(c2) shows the phase distribution of the light field of the square vortex array with a topological charge of +1. The phase difference between adjacent vortices is π.
[0033] Step 5: Superimpose the square array light spot formed in Step 3 and the square vortex array formed in Step 4 in space. Since the two array light fields have the same transverse period, they can completely overlap, thereby forming a square array single spiral beam with the best contrast.
[0034] Furthermore, since the adjacent square vortices and adjacent square light spots shown in Figure 2 have the same phase difference π, the formed spiral array not only has the same rotation direction but also has synchronism. As Figure 3 shown, when observed in three-dimensional space, a single spiral array light field with synchronous characteristics is formed, where the outer contour of each spiral corresponds to 30% of the maximum intensity of the spiral. Example 2
[0035] This example provides a method for forming a square array double spiral beam with synchronous characteristics by superimposing a square array optical vortex and a square array light spot.
[0036] Specifically, the method includes the following steps: Step 1: Configure the parameters of the four inner plane waves and the eight outer plane waves. It should be noted that the four inner plane waves in this embodiment are the same as those in Embodiment 1. Among them, as shown in Fig. 4(a1), the four inner plane waves have the same initial phase; as shown in Fig. 4(a2), the relative initial phases of the eight outer plane waves are -π / 2, π / 2, -π / 2, π / 2, π, 0, π, 0 in sequence; the wave vector components of the four inner plane waves and the eight outer plane waves satisfy: , the angle α shown in the figure is tan -1 (1 / 2), kr1 and kr2 are the transverse wave vector components of the eight outer plane waves and the four inner plane waves respectively.
[0037] Step 2: Adjust the amplitude of the four inner plane waves to A2 and the amplitude of the eight outer plane waves to A1, so that the two satisfy the proportional relationship A2≈1.266A1.
[0038] Step 3: As shown in Fig. 4(b1) and Fig. 4(c1), make the four inner plane waves interfere to form a square array light spot. Among them, Fig. 4(b1) shows the normalized intensity distribution of the light field of the square array light spot, and Fig. 4(c1) shows the phase distribution of the light field of the square array light spot. The phase difference between adjacent light spots is π.
[0039] Step 4: As shown in Fig. 4(b2) and Fig. 4(c2), make the eight outer plane waves interfere to form a square vortex array with a topological charge of -2. Among them, Fig. 4(b2) shows the normalized intensity distribution of the light field of the square vortex array with a topological charge of -2, and Fig. 4(c2) shows the phase distribution of the light field of the square vortex array with a topological charge of -2. The phase difference between adjacent vortices is π.
[0040] Step 5: Superimpose the square array light spot formed in Step 3 and the square vortex array formed in Step 4 in space. Since the two array light fields have the same period, they can completely overlap, thus forming a square array double helix beam with the best contrast.
[0041] Furthermore, since there is the same phase difference π between adjacent square vortices and adjacent square light spots shown in Fig. 4, the formed double helix array not only has the same rotation direction but also has synchronism. As Figure 5 shown, when observed in three-dimensional space, a double helix array light field with synchronous characteristics is formed, where the outer contour of each helix corresponds to 60% of the maximum intensity of the helix.
Claims
1. A method for generating a square array of synchronized spiral beams, characterized in that, It includes the following steps: Configure twelve plane waves with the same polarization state, including eight quasi-symmetric plane waves on the outside and four symmetric plane waves on the inside; Interfere the eight quasi-symmetric plane waves on the outside to form a square array vortex field, and interfere the four symmetric plane waves on the inside to form a square array light spot; Superimpose the square array vortex field and the square array light spot to form a square array spiral beam with synchronous characteristics.
2. The method for generating a square array synchronous spiral light beam according to claim 1, wherein: The eight quasi-symmetric plane waves on the outside are divided into two groups of four plane waves each that are mirror-symmetric with respect to the xoz plane, and the four plane waves in each group are uniformly distributed with respect to the optical axis; the four symmetric plane waves on the inside are symmetrically distributed with the optical axis as the center; the transverse wave vectors of the eight quasi-symmetric plane waves on the outside have a preset angle in the transverse coordinate system.
3. The method for generating a square array synchronous spiral beam according to claim 2, wherein: The four symmetric plane waves on the inside have the same initial phase; the relative initial phases of the eight quasi-symmetric plane waves on the outside are periodically distributed.
4. The method for generating a square array synchronous spiral beam according to claim 1, wherein: By adjusting the initial phases of the eight quasi-symmetric plane waves on the outside and the amplitude ratio of the inner and outer plane waves, a single spiral beam array or a double spiral beam array can be selectively formed.