Eccentric light beam projection device and eccentric dodging light beam projection device

Abstract

The utility model provides an eccentric light beam projection device and an eccentric uniform light beam projection device. The eccentric light beam projection device comprises a super lens; wherein under the action of the phase provided by the super lens, an incident light beam is modulated into an emergent light beam by the super lens; projection positions of light beam sections of the emergent light beams under different working distances on a two-dimensional plane where the super lens is located are different; the phase provided by the super lens comprises a focusing phase used for focusing the incident light beam; and the deflection phase is used for deflecting the incident light beam. The degree of freedom of eccentric translation of the optical system is improved, and the size and complexity of the optical system are reduced.

Description

Technical Field

[0001] The present disclosure relates to the technical field of optical metalenses, and in particular to an eccentric light beam projection device and an eccentric uniform light beam projection device. Background Art

[0002] In technical fields such as dual-beam interferometry, optical system debugging and calibration, laser processing, and structured light projection to detect depth information, there are extremely high requirements on the quality and characteristics of the light spot. Special optical systems are needed to project eccentric light spots to meet the needs of different application scenarios.

[0003] In the existing structured light projection detection depth information device, the eccentricity of the light spot is mainly achieved by repeatedly designing and adjusting the optical lens. The optical path diagram is as follows: Figure 1 As shown: The light source emits a carefully designed eccentric light. When the light spot hits the surface of the object, it is received by the sensor at a specific reflection angle. The sensor processes and analyzes the reflected light spot to accurately calculate the three-dimensional depth information of the detected object.

[0004] Although optical lenses can achieve spot eccentricity to a certain extent, they still have disadvantages in practical applications. Inevitably, the volume of the optical system increases, and the optical lenses require more complicated design and fine modulation to achieve the eccentricity effect. In addition, the more complex system structure leads to higher manufacturing difficulty and calibration requirements, which not only increases product costs, but also poses higher challenges to the stability and reliability of the system.

[0005] Therefore, there is a need for a more efficient, compact and cost-effective off-center beam projection device. Utility Model Content

[0006] In order to solve at least one of the above technical problems, the first aspect of the present disclosure provides an eccentric light beam projection device.

[0007] The eccentric light beam projection device includes a metalens, wherein, under the action of the phase provided by the metalens, the incident light beam is modulated by the metalens into an outgoing light beam; the beam cross-section of the outgoing light beam at different working distances has different projection positions on the two-dimensional plane where the metalens is located.

[0008] The phases provided by the metalens include: a focusing phase for focusing the incident light beam; and a deflection phase for deflecting the incident light beam.

[0009] Optionally, the above focusing phase satisfies:

[0010]

[0011] in, is the focusing phase, f is the focal length of the metalens, x and y are the coordinates of the metalens on the two-dimensional plane, k is the wave number, and the coefficient a is the coefficient of modulating the focusing phase.

[0012] Optionally, the above-mentioned deflection phase includes a first deflection phase for deflecting the incident light beam in the X-axis direction on the two-dimensional plane where the metalens is located:

[0013]

[0014] in, is the first deflection phase, k is the wave number, x is the coordinate on the X-axis, θ x is the deflection angle on the X axis.

[0015] Optionally, the above-mentioned deflection phase includes a second deflection phase for deflecting the incident light beam in the Y-axis direction on the two-dimensional plane where the metalens is located:

[0016]

[0017] in, is the second deflection phase, k is the wave number, y is the coordinate on the Y axis, θ y is the deflection angle on the Y axis.

[0018] Optionally, the above-mentioned eccentric light beam projection device also includes a light source; the light beam emitted by the above-mentioned light source is the incident light beam of the super lens.

[0019] Optionally, the superlens comprises a substrate and a superstructure unit arranged on one side of the substrate, and each vertex and center of the superstructure unit are provided with a micro-nano structure.

[0020] Optionally, the superstructure unit is in the shape of a regular hexagon, a square or a fan.

[0021] Optionally, the micro-nano structure includes nano-fins or nano-pillars.

[0022] Optionally, the arrangement period of the micro-nano structures is greater than or equal to 0.3λc and less than or equal to 2λc, wherein λc is the central wavelength of the incident light beam.

[0023] Optionally, the superlens further includes a filling material, and the filling material is filled between the micro-nano structures.

[0024] A second aspect of the present disclosure provides an eccentric uniform light beam projection device.

[0025] The device includes a superlens array; the superlens array includes at least two superlenses as described above; the size of each superlens in the superlens array is configured to be randomly distributed, or the focal length of each superlens in the superlens array is configured to be randomly distributed.

[0026] Optionally, the size of each of the above-mentioned super lenses is configured to be randomly distributed; wherein, the size of each super lens is configured to be an ideal size based on non-interference conditions, and the actual size of each super lens is randomly distributed within a preset offset range based on the ideal size.

[0027] Optionally, the preset offset range based on the above ideal size is less than or equal to 10%.

[0028] Optionally, the focal lengths of the above-mentioned metalenses are configured to be randomly distributed; wherein the focal lengths of the above-mentioned metalenses are configured to be ideal focal lengths based on non-interference conditions, and the actual focal lengths of the above-mentioned metalenses are randomly distributed within a preset offset range based on the above-mentioned ideal focal lengths.

[0029] Optionally, the preset offset range based on the above-mentioned ideal focal length is less than or equal to 10%.

[0030] The technical solution disclosed in the present invention uses the focusing phase of a single metalens to make the outgoing light beam converge at a near distance and then diverge at a far distance, and the light spot is freely eccentrically translated by superimposing the deflection phase. Compared with the traditional optical solution, this solution can reduce the complexity of the design of the optical system, improve the degree of modulation freedom, and reduce the volume and cost of the optical system. Therefore, the present invention provides an efficient, compact and cost-effective light beam projection device for the optical field. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The accompanying drawings are included to provide a further understanding of the present disclosure and are incorporated in and constitute a part of this specification. The accompanying drawings illustrate embodiments of the present disclosure and together with the following description serve to explain the principles of the present disclosure.

[0032] Figure 1 The schematic diagram of the optical path of structured light detecting object depth information in the prior art is shown;

[0033] Figure 2 The schematic diagram of the optical path of a uniform light spot obtained by eccentricity in a traditional optical solution is shown;

[0034] Figure 3 A schematic diagram of an eccentric light beam projection device provided by an embodiment of the present disclosure is shown;

[0035] Figure 4 A schematic diagram showing the phase distribution of a metalens without superimposed deflection phase provided in Example 1 of the present disclosure is shown;

[0036] Figure 5 A schematic diagram of light intensity distribution on the observation surface of a metalens without superimposed deflection phase provided in Example 1 of the present disclosure is shown;

[0037] Figure 6A schematic diagram of the cross-sectional light intensity in the y direction of the observation surface of the metalens without superimposed deflection phase provided in Example 1 of the present disclosure is shown;

[0038] Figure 7 A schematic diagram showing the phase distribution of a super-lens with superimposed deflection phase provided in Example 1 of the present disclosure is shown;

[0039] Figure 8 A schematic diagram of light intensity distribution on the observation surface of a superlens with superimposed deflection phase provided in Example 1 of the present disclosure is shown;

[0040] Fig. 9 A schematic diagram of the cross-sectional light intensity in the y direction of the observation surface of the super-lens with superimposed deflection phase provided in Example 1 of the present disclosure is shown;

[0041] Fig.10 A schematic diagram showing the phase distribution of a metalens without superimposed deflection phase provided in Example 2 of the present disclosure is shown;

[0042] Fig.11 A schematic diagram of light intensity distribution on the observation surface of a metalens without superimposed deflection phase provided in Example 2 of the present disclosure is shown;

[0043] Fig.12 A schematic diagram of the cross-sectional light intensity in the x direction of the observation surface of the metalens without superimposed deflection phase provided in Example 2 of the present disclosure is shown;

[0044] Fig.13 A schematic diagram showing the phase distribution of a super-lens with superimposed deflection phase provided in Example 2 of the present disclosure is shown;

[0045] Fig.14 A schematic diagram of light intensity distribution on the observation surface of a superlens with superimposed deflection phase provided in Example 2 of the present disclosure is shown;

[0046] Fig.15 A schematic diagram of the cross-sectional light intensity in the x direction of the observation surface of the super-lens with superimposed deflection phase provided in Example 2 of the present disclosure is shown;

[0047] Fig.16 A schematic diagram showing the phase distribution of a metalens without superimposed deflection phase provided in Example 3 of the present disclosure is shown;

[0048] Fig.17 A schematic diagram of light intensity distribution on the observation surface of a metalens without superimposed deflection phase provided in Example 3 of the present disclosure is shown;

[0049] Fig.18 A schematic diagram of the cross-sectional light intensity in the x direction of the observation surface of the metalens without superimposed deflection phase provided in Example 3 of the present disclosure is shown;

[0050] Fig.19A schematic diagram of the cross-sectional light intensity in the y direction of the observation surface of the metalens without superimposed deflection phase provided in Example 3 of the present disclosure is shown;

[0051] Fig. 20 A schematic diagram showing the phase distribution of a super-lens with superimposed deflection phase provided in Example 3 of the present disclosure is shown;

[0052] Fig.21 A schematic diagram of light intensity distribution on the observation surface of a superlens with superimposed deflection phase provided in Example 3 of the present disclosure is shown;

[0053] Fig. 22 A schematic diagram of the cross-sectional light intensity in the x direction of the observation surface of the super-lens with superimposed deflection phase provided in Example 3 of the present disclosure is shown;

[0054] Fig.23 A schematic diagram of the cross-sectional light intensity in the y direction of the observation surface of the super-lens with superimposed deflection phase provided in Example 3 of the present disclosure is shown.

[0055] The reference numerals in the figure represent respectively:

[0056] 10-light source; 20-super lens; 30-observation surface;

[0057] 21-substrate; 22-micro-nanostructure. DETAILED DESCRIPTION

[0058] The present disclosure will be described more fully below with reference to the accompanying drawings, in which various embodiments are shown. However, the present disclosure can be implemented in many different ways and should not be construed as being limited to the embodiments set forth herein. On the contrary, these embodiments are provided so that the present disclosure will be exhaustive and complete, and will fully convey the scope of the present disclosure to those skilled in the art. The same reference numerals throughout the text represent the same components. Furthermore, in the accompanying drawings, the thickness, ratios, and sizes of the components are exaggerated for clarity.

[0059] The terms used herein are only used for the purpose of describing specific embodiments and are not intended to be limiting. Unless the context clearly indicates otherwise, "one", "the", "at least one" as used herein do not represent a limitation on quantity, but are intended to include both the singular and the plural. For example, unless the context clearly indicates otherwise, "a component" has the same meaning as "at least one component". "At least one" should not be interpreted as being limited to the number "one". "Or" means "and / or". The term "and / or" includes any and all combinations of one or more of the associated listed items.

[0060] Unless otherwise defined, all terms used herein, including technical and scientific terms, have the same meanings as those generally understood by those skilled in the art. Terms defined in commonly used dictionaries should be interpreted as having the same meanings as in the relevant technical context, and unless clearly defined in the specification, these terms are not interpreted as having formal meanings in an idealized or overly formal sense.

[0061] The meaning of “include” or “comprising” specifies properties, quantities, steps, operations, components, parts or a combination thereof, but does not exclude other properties, quantities, steps, operations, components, parts or a combination thereof.

[0062] Embodiments are described herein with reference to cross-sectional views as idealized embodiments. Thus, variations in shape relative to the illustrated diagram are anticipated as a result of, for example, manufacturing techniques and / or tolerances. Therefore, the embodiments described herein should not be interpreted as being limited to the specific shapes of the regions as shown herein, but should include deviations in shape due to, for example, manufacturing. For example, a region shown or described as flat may typically have rough and / or nonlinear features. Moreover, the sharp angles shown may be rounded. Therefore, the regions shown in the figures are schematic in nature, and their shapes are not intended to illustrate the precise shape of the regions and are not intended to limit the scope of the claims.

[0063] Hereinafter, exemplary embodiments according to the present disclosure will be described with reference to the accompanying drawings.

[0064] The present disclosure provides an eccentric light beam projection device, such as Figure 3 As shown, the device coaxially arranges a light source 10, a super lens 20, and an observation surface 30 in sequence. The super lens 20 includes a substrate 21 and a super structure unit arranged on one side of the substrate, each vertex and center of the super structure unit are provided with a micro-nano structure 22, and the filling material is filled between the micro-nano structures 22.

[0065] Under the action of the phase provided by the superlens 20, the incident light beam is modulated by the superlens 20 into an outgoing light beam; the beam cross section of the outgoing light beam at different working distances has different projection positions on the two-dimensional plane where the superlens 20 is located; wherein the working distance is the distance between the observation plane 30 and the superlens 20, and the size of this distance directly affects the projection position and the size of the light spot. When the distance increases, the size of the projected image will also increase accordingly; the different projection positions at different working distances refer to that when the distance between the observation plane 30 and the superlens 20 is different, light spots of different sizes are projected on the observation plane 30, and the projection positions are different. After the light spots are superimposed on the observation plane 30, an eccentric effect of the light spots is achieved.

[0066] The phases provided by the metalens 20 include: a focusing phase for focusing the incident light beam, by adding the focusing phase, the incident light beam is refracted, reflected and transmitted, and focused into a very small area, thereby increasing the energy density, and concentrating the outgoing light beam onto the observation surface 30 to form a clear light spot, thereby achieving the effect of light beam concentration and energy improvement; a deflection phase for deflecting the incident light beam, by adding the deflection phase, the outgoing light beam is eccentrically emitted along the two-dimensional plane where the metalens 20 is located, and the optical axis of the eccentrically emitted light beam is inclined to the exit surface, thereby achieving an eccentric effect.

[0067] The focusing phase formula of the lens is:

[0068]

[0069] in, is the focusing phase, f is the focal length of the superlens 20, x and y are the coordinates of the superlens 20 on the two-dimensional plane, and k is the wave number, which is obtained by the following formula:

[0070] k=2π / λ

[0071] λ is the central wavelength of the incident light beam. A coefficient a is now introduced to adjust the focusing effect of the above-mentioned focusing phase in the x and y directions, thereby obtaining the focusing phase of the metalens 20 of this embodiment:

[0072]

[0073] in, is the focusing phase, f is the focal length of the superlens 20, x and y are the coordinates of the superlens 20 on the two-dimensional plane, k is the wave number, λ is the central wavelength of the incident light beam, and a coefficient is the coefficient of modulating the focusing phase.

[0074] In an optional embodiment, when the coefficient a of the focusing phase is equal to 1, the focusing effects in different directions are consistent.

[0075] In an optional embodiment, when the coefficient a of the focusing phase is not equal to 1, the focusing effects in different directions are inconsistent.

[0076] The above configuration can be used to adjust the focusing degree / divergence angle of the outgoing light beam. The two-dimensional plane where the super lens 20 is located can be divided into two coordinate axes, namely the X axis and the Y axis. The positive direction of the X axis is set to the right, the positive direction of the Y axis is set to the top, and the deflection angle is the angle with the coordinate axis.

[0077] In an optional embodiment, the deflection phase includes a first deflection phase for deflecting the incident light beam in the X-axis direction on the two-dimensional plane where the metalens 20 is located, satisfying:

[0078]

[0079] in, is the first deflection phase, k is the wave number, x is the coordinate on the X-axis, θ x is the deflection angle on the X axis.

[0080] When a deflection phase is arranged in the positive direction of the X-axis, the outgoing light beam of the super lens 20 achieves an effect of being deflected to the right as a whole.

[0081] In an optional embodiment, the deflection phase includes a second deflection phase for deflecting the incident light beam in the Y-axis direction on the two-dimensional plane where the metalens is located, satisfying:

[0082]

[0083] in, is the second deflection phase, k is the wave number, y is the coordinate on the Y axis, θ y is the deflection angle on the Y axis.

[0084] A deflection phase is arranged in the positive direction of the Y-axis, so that the outgoing light beam of the super lens 20 achieves an effect of overall upward deflection.

[0085] In an optional embodiment, a deflection phase is applied in the positive direction of the X-axis and the positive direction of the Y-axis, so that the outgoing light beam of the superlens 20 can achieve an overall deflection effect toward the upper right.

[0086] The above device can make the light spot freely eccentrically translated based on the single-chip super lens 20. Compared with the traditional optical solution, this solution can reduce the complexity of the design of the optical system and improve the degree of freedom of modulation. At the same time, the super lens 20 can also reduce the volume and cost of the optical system.

[0087] In the related art, in order to obtain a uniform eccentric light spot, Figure 2 As shown in the figure, it is often necessary to add additional optical lenses (such as a light homogenizer and a lens combination) to finely modulate the initial light spot to achieve the desired eccentricity effect. Although adding additional optical lenses can achieve light homogenization and eccentricity of the light spot to a certain extent, there are still disadvantages in practical applications, which inevitably leads to an increase in the volume of the optical system. In addition, a more complex system structure means higher manufacturing difficulty and calibration requirements, which not only increases the product cost, but also poses higher challenges to the stability and reliability of the system.

[0088] To this end, the second aspect of the present disclosure provides an eccentric uniform light beam projection device, which includes a superlens array; the superlens array includes at least two superlenses 20 as described above; the size of each superlens 20 in the superlens array is configured to be randomly distributed, or the focal length of each superlens 20 in the superlens array is configured to be randomly distributed.

[0089] Specifically, the focusing phase of a single metalens makes the outgoing light beam converge at a near distance and then diverge at a far distance; the outgoing light beams of multiple metalens diverge at a far distance and are partially mixed, thereby achieving uniform light.

[0090] If the metalenses are exactly the same, the outgoing light beams of adjacent metalenses may interfere with each other, resulting in the light intensity at the splicing position being more prominent, affecting the uniformity of the light intensity. Therefore, random factors are applied to the metalenses, preferably including random size and focal length, thereby breaking the interference and improving the uniformity of the light intensity.

[0091] In an optional embodiment, the size of each of the above-mentioned super lenses 20 is configured to be randomly distributed; wherein, the size of each super lens 20 is configured to be an ideal size based on non-interference conditions, and the actual size of each super lens 20 is randomly distributed within a preset offset range based on the above-mentioned ideal size.

[0092] Specifically, without considering the mutual interference between the output light beams of adjacent metalenses, the size of each metalens 20 is configured to be an ideal size (for example, a uniform size); according to the determined ideal size, an allowable preset offset range is set for the size of each metalens 20, and the preset offset range is configured as an interval around the ideal size. Within the preset offset range, a random value is assigned to the size of each metalens 20. This ensures that the size of each metalens 20 has a certain degree of randomness while maintaining a certain consistency, and ensures that the size difference between each metalens 20 is large enough to avoid interference that may be caused by periodic or regular arrangement.

[0093] In an optional embodiment, the preset offset range based on the above-mentioned ideal size is less than or equal to 10%.

[0094] In an optional embodiment, the focal lengths of the above-mentioned metalenses 20 are configured to be randomly distributed; wherein the focal lengths of the above-mentioned metalenses 20 are configured to be ideal focal lengths based on non-interference conditions, and the actual focal lengths of the above-mentioned metalenses 20 are randomly distributed within a preset offset range based on the above-mentioned ideal focal lengths.

[0095] Specifically, without considering the mutual interference between the outgoing light beams of adjacent metalenses, the focal length of each metalens 20 is configured as an ideal focal length; according to the determined ideal focal length, an allowable preset offset range is set for the focal length of each metalens 20, and the preset offset range is configured as an interval around the ideal focal length. Within the preset offset range, a random value is assigned to the focal length of each metalens 20. This ensures that the focal length of each metalens 20 has a certain degree of randomness while maintaining a certain consistency, and ensures that the focal length difference between each metalens 20 is large enough to avoid interference.

[0096] In an optional embodiment, the preset offset range based on the above-mentioned ideal focal length is less than or equal to 10%.

[0097] Taking advantage of the free superposition of metalens phase modulation, on the basis of the original metalens realizing the focusing and eccentric functional phase, the metalens is arrayed and randomized to achieve the uniform light effect, and then eccentrically translated on the observation plane to obtain an eccentric uniform light spot.

[0098] Therefore, compared with the related art, the above configuration uses a metalens array to achieve the integration of light homogenization and eccentricity functions, which significantly reduces the overall volume and complexity of the optical system. Specifically, through the precise design and optimization of the metalens, both eccentricity and light homogenization requirements can be met without the need for additional optical lenses or complex modulation steps. This configuration not only simplifies the design of the optical system, but also reduces the difficulty of manufacturing and calibration, thereby further reducing the cost of the optical system. Therefore, the technical solution in the present disclosure provides a new option for the optical field that is efficient, compact and cost-effective.

[0099] The following examples illustrate the degrees of freedom of eccentric translation of a uniform light spot obtained according to an embodiment of the present disclosure.

[0100] Embodiment 1

[0101] In this embodiment, the light source 10 emits a plane wave with a center wavelength of 940 nm and is incident normally. The light source 10 is 10 mm away from the metalens 20, and the metalens 20 is 1 m away from the observation surface 30. When no deflection phase is added, the uniform light spot projected by the metalens 20 has a field of view of about 17 degrees in the x direction and a field of view of about 23 degrees in the y direction. The phase distribution diagram of the metalens 20 uses length coordinates, while the y-direction cross-sectional light intensity in the light intensity distribution diagram of the observation surface 30 uses angle coordinates based on the field of view angle.

[0102] When the deflection phase is not added, Figure 4-6 As shown, the phase distribution of the unsuperimposed deflection phase superlens, the light intensity distribution on the observation surface, and the schematic diagram of the cross-sectional light intensity in the y direction are respectively shown.

[0103] After adding the deflection phase, the uniform spot is translated 5 degrees in the positive y-semi-axis direction, as shown in Figure 7-9 As shown, the phase distribution of the superlens with superimposed deflection phase, the light intensity distribution on the observation surface, and the schematic diagram of the cross-sectional light intensity in the y direction are respectively shown.

[0104] As can be seen from the above embodiments, the incident light beam itself has a uniform light intensity distribution, and the light intensity of the outgoing light beam of the metalens is uniformly distributed. Therefore, this embodiment can achieve the free translation of the uniform light spot in the vertical direction on the observation surface.

[0105] Embodiment 2

[0106] In this embodiment, the light source 10 emits a plane wave with a center wavelength of 940 nm. The light source 10 is 10 mm away from the metalens 20, and the metalens 20 is 1 m away from the observation surface 30. When no deflection phase is added, the uniform light spot projected by the metalens 20 has a field of view of about 17 degrees in the x direction and a field of view of about 23 degrees in the y direction. The phase distribution diagram of the metalens 20 uses length coordinates, while the light intensity of the x-direction cross section in the light intensity distribution diagram of the observation surface 30 uses angle coordinates based on the field of view.

[0107] When the deflection phase is not added, Figure 10-12 As shown, schematic diagrams of the metalens phase distribution without superimposed deflection phase, the light intensity distribution on the observation surface, and the cross-sectional light intensity in the x direction are shown respectively.

[0108] After adding the deflection phase, the uniform spot is translated 5 degrees in the positive x-axis direction, as shown in Figure 13-15 As shown, schematic diagrams of the phase distribution of the superlens with superimposed deflection phase, the light intensity distribution on the observation surface, and the cross-sectional light intensity in the x direction are shown respectively.

[0109] It can be seen from the above embodiments that this embodiment can realize the free translation of the uniform light spot along the horizontal direction on the observation surface.

[0110] Embodiment 3

[0111] In this embodiment, the light source 10 emits a plane wave with a center wavelength of 940 nm. The light source 10 is 10 mm away from the metalens 20, and the metalens 20 is 1 m away from the observation surface 30. When no deflection phase is added, the uniform light spot projected by the metalens 20 has a field of view of about 17 degrees in the x direction and a field of view of about 23 degrees in the y direction. The phase distribution diagram of the metalens 20 uses length coordinates, while the cross-sectional light intensities in the x and y directions in the light intensity distribution diagram of the observation surface 30 both use angle coordinates based on the field of view angle.

[0112] When the deflection phase is not added, Figure 16-19 As shown, schematic diagrams of the phase distribution of the metalens without superimposed deflection phase, the light intensity distribution on the observation surface, and the cross-sectional light intensity in the x direction and the y direction (in the direction of 45 degrees of the positive x-axis angle) are shown respectively.

[0113] After adding the deflection phase, the uniform spot is translated 5 degrees along the positive x-axis and the positive y-axis at the same time, that is, it is translated along the direction of 45 degrees with the positive x-axis. Degree, such as Figure 20-23 As shown, schematic diagrams of the phase distribution of the super-lens with superimposed deflection phase, the light intensity distribution on the observation surface, and the cross-sectional light intensity in the x-direction and the y-direction (in the direction of 45 degrees of the positive x-axis angle) are shown respectively.

[0114] It can be seen from the above embodiments that the projection device provided by the embodiments of the present disclosure achieves eccentricity in the direction required for uniform light generation, and an obvious eccentricity angle can be observed, thereby improving the degree of freedom and accuracy of modulation.

[0115] In summary, compared with traditional devices, the present invention significantly optimizes the volume and system complexity of the optical system that requires an eccentric uniform light spot; and can achieve free two-dimensional translation of the eccentric uniform light spot on the observation surface, thereby improving the degree of freedom of modulation.

[0116] It should be noted that the metalens provided in the embodiments of the present disclosure can be processed by semiconductor technology, and has the advantages of light weight, thin thickness, simple structure and process, low cost and high consistency in mass production.

[0117] In summary, the eccentric light beam projection device and the eccentric light uniform light beam projection device provided by the embodiments of the present disclosure can achieve precise control of the shape, size and position of the light spot by precisely designing the sub-wavelength micro-nano structure of the metalens, while ensuring the uniform distribution of the light intensity inside the light spot. This metalens has broad application prospects in the fields of dual-beam interferometry, optical system debugging and calibration, laser processing, and structured light projection to detect depth information.

[0118] The above is only a specific implementation of the embodiment of the present disclosure, but the protection scope of the embodiment of the present disclosure is not limited thereto. Any technician familiar with the technical field can easily think of changes or replacements within the technical scope disclosed in the embodiment of the present application, which should be included in the protection scope of the embodiment of the present application. Therefore, the protection scope of the embodiment of the present application should be based on the protection scope of the claims.

Claims

1. An eccentric light beam projection device, characterized in that: The eccentric light beam projection device comprises a super lens (20); Wherein, under the action of the phase provided by the superlens (20), the incident light beam is modulated by the superlens (20) into an outgoing light beam; the beam cross section of the outgoing light beam at different working distances has different projection positions on the two-dimensional plane where the superlens (20) is located; The phase provided by the metalens (20) includes: a focusing phase for focusing the incident light beam; and a deflection phase for deflecting the incident light beam.

2. The eccentric light beam projection device according to claim 1, characterized in that: The focusing phase satisfies: in, is the focusing phase, f is the focal length of the superlens (20), x and y are the coordinates of the superlens (20) on the two-dimensional plane, k is the wave number, and coefficient a is the coefficient for modulating the focusing phase.

3. The eccentric light beam projection device according to claim 1, characterized in that: The deflection phase includes a first deflection phase for deflecting the incident light beam in the X-axis direction on the two-dimensional plane where the metalens (20) is located: in, is the first deflection phase, k is the wave number, x is the coordinate on the X-axis, θ x is the deflection angle on the X-axis.

4. The eccentric light beam projection device according to claim 1 or 3, characterized in that: The deflection phase includes a second deflection phase for deflecting the incident light beam in the Y-axis direction on the two-dimensional plane where the metalens (20) is located: in, is the second deflection phase, k is the wave number, y is the coordinate on the Y axis, θ y is the deflection angle on the Y axis.

5. The eccentric light beam projection device according to claim 1, characterized in that: The eccentric light beam projection device also includes a light source (10); the light beam emitted by the light source is the incident light beam of the super lens (20).

6. An eccentric uniform light beam projection device, characterized in that: The eccentric light-homogenizing beam projection device comprises a metalens array; the metalens array comprises at least two eccentric light beam projection devices as described in any one of claims 1 to 5 above; The size of each super lens (20) in the super lens array is configured to be randomly distributed, or the focal length of each super lens (20) in the super lens array is configured to be randomly distributed.

7. The device according to claim 6, characterized in that The size of each metalens (20) is configured to be randomly distributed; wherein the size of each metalens (20) is configured to be an ideal size based on non-interference conditions, and the actual size of each metalens (20) is randomly distributed within a preset offset range based on the ideal size.

8. The device according to claim 7, characterized in that The preset deviation range based on the ideal size is less than or equal to 10%.

9. The device according to claim 6, characterized in that The focal lengths of the metalenses (20) are configured to be randomly distributed; wherein the focal lengths of the metalenses (20) are configured to be ideal focal lengths based on non-interference conditions, and the actual focal lengths of the metalenses (20) are randomly distributed within a preset offset range based on the ideal focal lengths.

10. The device according to claim 9, characterized in that The preset offset range based on the ideal focal length is less than or equal to 10%.

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