Sunlight collecting device formed by combining plurality of sub-lens systems

Abstract

A sunlight collecting device formed by combining a plurality of sub-lens systems belongs to the technical field of sunlight collection. In the prior art, sunlight collection efficiency is low, and a collection device is complex in structure and large in size. According to the invention, the sub-lens system has a Galileo structure; the m * n sub-lens systems are combined to form a sub-lens system array, the sub-lens system array is composed of a convex-plane lens array, a plano-convex lens array and a biconcave lens array in sequence from the sunlight incidence direction to the sunlight emergence direction, and the subsequent condensing lens is located on a light emergence path of the sub-lens array. The subsequent condensing lens and the biconcave lens array share the same optical axis and have the same aperture; the convex-plane lens array and the plano-convex lens array can be staggered in the x direction or / and the y direction which are perpendicular to each other, and the x direction and the y direction are both perpendicular to the z direction where the common optical axis of the subsequent condensing lens and the biconcave lens array is located. According to the invention, sunlight is tracked and received in the whole daytime in a large view field range in an optical mode and assisted by small-amplitude and simple mechanical actions.

Description

Technical Field

[0001] The invention discloses a sunlight collecting device composed of a plurality of sub-lens systems, belonging to the field of sunlight collecting technology. Background Art

[0002] In existing daylight collection devices, the usual daylight collection device adopts a non-array single lens form, and the realization of daylight tracking requires the use of mechanical mechanisms such as omnidirectional pan-tilt heads, three-dimensional robots, theodolite mounts, etc. The disadvantage is that the single lens mirror has a high sagittal height, and the thickness of the lens also increases with the increase of the aperture. The structure of the mechanical device for realizing daylight tracking is also relatively complex, and the mechanical action is often an arc motion in at least two directions. All of these result in the daylight collection device being large in size and weight, complex in tracking control, and high in manufacturing cost.

[0003] Daylight collection is a link in the process of solar energy utilization. The position of the daylight source (the sun) moves with the change of seasons and time, which is a core factor restricting the improvement of daylight collection efficiency. In the prior art, daylight collection devices either collect daylight in a follow-up manner or collect daylight in other ways while stationary.

[0004] A Chinese utility model patent with application number 202321079062.7 and name "An angle-adjustable solar energy collecting device" provides a solution that collects sunlight in a real-time swinging manner, tracks sunlight by mechanically adjusting the angle of the collecting plate, and improves the collection efficiency. However, its structure is complex and its volume is large, so the mechanical movement is also complex, it occupies a large space, has a high manufacturing cost, and requires a lot of maintenance.

[0005] A Chinese invention patent with application number 201910390715.5 and name "A light-collecting hole array plate for a light collector" provides another sunlight collection solution, which collects sunlight in a static manner. Although this solution can improve the collection efficiency, its structure is still relatively complex and uses large-area multi-unit multi-layer array plates, such as lens array plates, conical array plates, and light-collecting hole array plates, which are difficult to manufacture and assemble. Summary of the invention

[0006] In order to simplify the structure of the daylight collection device, reduce its volume, and lower the manufacturing, assembly and use costs of the daylight collection device while improving the daylight collection efficiency, we proposed a solution called "a daylight collection device composed of several sub-lens systems".

[0007] In the present invention, if Figure 1As shown, the sub-lens system has a Galilean structure, and its components are convex-planar lens 1, plano-convex lens 2, and biconcave lens 3 in order from the direction of sunlight incidence to the direction of sunlight emission. The spatial positions of the plano-convex lens 1 and the plano-convex lens 2 coincide with each other, the convex mirror surface of the plano-convex lens 2 is separated from the incident concave mirror surface of the biconcave lens 3, and the incident angle θ of the convex mirror surface of the convex-planar lens 1 is in the range of 0 to ±40°. The incident light enters the sub-lens system from the convex mirror surface of the convex-planar lens 1, and then is refracted twice by the plano-convex lens 2 and the biconcave lens 3 in sequence, and is emitted at an exit angle of 0°; as shown in FIG. Figure 2 As shown, m×n sub-lens systems are combined to form a sub-lens system array, and the components of the sub-lens system array are convex-plano lens array 1S, plano-convex lens array 2S, and biconcave lens array 3S in order from the direction of sunlight incidence to the direction of sunlight emission. Figure 2 , Figure 3 As shown, the subsequent focusing lens 4 is located on the light output path of the sub-lens array, and the subsequent focusing lens 4 and the biconcave lens array 3S share the same optical axis and have the same aperture; the convex-planar lens array 1S and the plano-convex lens array 2S can be shifted in the mutually perpendicular x direction or / and y direction, respectively, and the x direction and the y direction are both perpendicular to the z direction where the common optical axis of the subsequent focusing lens 4 and the biconcave lens array 3S is located.

[0008] The technical effects of the present invention are as follows.

[0009] The present invention replaces a single lens with the same aperture with a convex-plano lens array 1S, a plano-convex lens array 2S, and a biconcave lens array 3S of m×n=5×5. Since the sagittal height of the sub-lens is much smaller than the sagittal height of the single lens, the thickness of each lens array is very small, thereby greatly reducing the volume and weight of the daylight collecting device.

[0010] When the convex-plano lens array 1S and the plano-convex lens array 2S of the present invention are shifted from the position of incident angle θ=0° to the lower left in the x direction to the position of incident angle θ=-40°, as shown in FIG. Figure 4 , Figure 5 As shown, the sunlight collecting device of the present invention can receive sunlight from the horizon; when the convex-plano lens array 1S and the plano-convex lens array 2S of the present invention are shifted from the position of incident angle θ=0° to the upper right in the x direction to the position of incident angle θ=40°, as shown in FIG. Figure 4 , Figure 6As shown, the daylight collecting device of the present invention can receive sunlight in the sky, that is, in the pitch direction, the present invention can track and collect light within a maximum field angle range of 80°. In addition, when the convex-planar lens array 1S and the plano-convex lens array 2S in the present invention are displaced in the y direction from the incident angle θ=0°, similarly, they can receive sunlight at sunrise and sunset, as well as sunlight at noon, that is, in the azimuth direction, the present invention can also track and collect light within a maximum field angle range of 80°. When the dislocation of the convex-planar lens array 1S and the plano-convex lens array 2S in the present invention in the two straight lines of the x direction and the y direction is synthesized, it can achieve large field tracking and receiving of sunlight from sunrise to sunset, and when the aperture of the sub-lens system is 5mm, the dislocation is in the millimeter level, and the maximum dislocation distance does not exceed 20mm. The prior art is a centimeter-level arc motion in two directions. It can be seen that compared with the prior art, the present invention can track and receive sunlight throughout the day in a large field of view in an optical manner, assisted by small and simple mechanical movements, which reflects the characteristics of the daylight collection device of the present invention, such as simple structure, small size, small space occupied during operation, and low manufacturing, assembly and use costs.

[0011] Since the daylight collecting device of the present invention tracks and collects light within a wide field of view, or in other words, gazes at the sun, rather than collecting light at a wide field of view, the directionality of the sunlight received at all times is very strong. Although the aperture of the daylight collecting device is not large, the directional efficiency and tracking quality are high, and it can still effectively collect sunlight despite the divergence of sunlight. This technical effect can also be seen from the following description: the sub-lens system array in the present invention receives sunlight at multiple angles in a wide angle range of 0 to ±40°, in the two tracking directions of pitch and azimuth, and emits parallel light at a single 0° angle, which is then converged into a point light spot by the subsequent focusing lens 4, as shown in FIG. Figure 3 , Figure 5 , Figure 6 , Figure 7 As shown, the power density of the light spot is increased, so that a smaller solar panel can collect more light energy and ultimately complete the collection of sunlight. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 Schematic diagram of the sub-lens system structure and optical path in the present invention.

[0013] Figure 2 This is a three-dimensional schematic diagram of the overall structure of the sunlight collection device of the present invention, which also serves as an abstract drawing.

[0014] Figure 3 The figure is a schematic diagram of the overall structure and optical path of the sunlight collection device of the present invention.

[0015] Figure 4Schematic diagram of the sub-lens system array structure and the optical path at an incident angle of 0° in the present invention.

[0016] Figure 5 The figure is a schematic diagram of the overall structure of the sunlight collection device of the present invention and the light path at an incident angle of -40°.

[0017] Figure 6 The figure is a schematic diagram of the overall structure of the sunlight collection device of the present invention and the light path at an incident angle of +40°.

[0018] Figure 7 The figure is a schematic diagram of the shape and optical path of the subsequent focusing lens in the sunlight collecting device of the present invention.

[0019] Figure 8 It is a schematic diagram of the dislocation state and optical path of the convex-plano lens and the plano-convex lens of the sub-lens system of the present invention within the incident angle range of 0°<θ≦±40°.

[0020] Fig. 9 The figure is a curve diagram showing the relationship between the displacement distance of the sub-lens system and the incident angle of sunlight in the present invention. DETAILED DESCRIPTION

[0021] Further technical features of the present invention are described as follows.

[0022] The lens data of the sub-lens system is given in the following table, where the units of curvature radius, thickness and spacing are all mm.

[0023]

[0024] The distance between the biconcave lens 3 and the subsequent condenser lens 4 is 20 mm.

[0025] The introduction of the cone coefficient k and the second-order term coefficient α1, the fourth-order term coefficient α2, the sixth-order term coefficient α3, and the eighth-order term coefficient α4 can better achieve the light-collecting effect of the present invention.

[0026] The lens data of the subsequent condenser lens 4 is given in the following table, where the units of the curvature radius and thickness are both mm.

[0027]

[0028] The distance from the rear mirror surface of the subsequent condenser lens 4 to the image plane is 15.95 mm.

[0029] The even-order aspheric surface is determined by the formula:

[0030]

[0031] Where: z is the distance from each non-vertex point on the even-order aspheric surface to the optical axis, c is the reciprocal of the radius of curvature, r is the free variable of the net aperture of the aspheric lens, k is the cone coefficient, α1 is the second-order term coefficient, α2 is the fourth-order term coefficient, α3 is the sixth-order term coefficient, and α4 is the eighth-order term coefficient.

[0032] The aperture range of the sub-lens system is 1 to 12 mm, for example 5 mm; the sub-lens system array is composed of m×n=3×3 to 9×9 sub-lens systems arranged in rows and columns, such as m×n=5×5. The cross-section of the sunlight beam that can be received by the sub-lens system array is rectangular, with a size of 20 mm×20 mm.

[0033] The convex-plano lens array 1S, plano-convex lens array 2S, biconcave lens array 3S, and subsequent focusing lens 4 in the sub-lens system array are all made of PMMA optical plastics, which are injection molded in one step. The Abbe number of PMMA optical plastics is 57.441 and the refractive index is 1.4918.

[0034] When receiving sunlight with an incident angle θ of 0°, the optical axes of the convex-plano lens 1, the plano-convex lens 2, and the biconcave lens 3 in the sub-lens system coincide with each other. Figure 4 As shown in FIG. 1 , when receiving sunlight with an incident angle θ of 0°<θ≦±40°, as Figure 5 , Figure 6 As shown, the displacement distance of the convex-planar lens 1 along the x direction or y direction perpendicular to the optical axis is Δ2, as shown in Figure 8 As shown, the plano-convex lens 2 also shifts in the same direction by Δ2-Δ1, and the shift amplitude is smaller than that of the convex-planar lens 1. During the shifting process, the optical axes of the convex-planar lens 1 and the plano-convex lens 2 form a distance Δ1;

[0035] The corresponding relationship between Δ2 and θ is:

[0036]

[0037] Where: a1, b1 are the linear coefficient and quadratic coefficient of convex-planar lens 1 respectively;

[0038] The corresponding relationship between Δ1 and θ is:

[0039]

[0040] Wherein: a2, b2 are the linear coefficient and the quadratic coefficient of the plano-convex lens 2 respectively.

[0041] According to the linear term coefficient and quadratic term coefficient given in the following table,

[0042] <![CDATA[a2]]> <![CDATA[b2]]> <![CDATA[a1]]> <![CDATA[b1]]> 0.1848 0.001154 0.307 0.0007758

[0043] Then, according to the values ​​of Δ2 and Δ1 set in the table below, the convex-plano lens 1 and the plano-convex lens 2 can be moved to track and receive sunlight within the range of the incident angle θ of 0° to 40°. Figure 6 , Figure 7 shown.

[0044] Angle of incidence θ <![CDATA[Displacement distance Δ2]]> Optical axis spacing Δ1 0° 0 0 10° 2.744 1.492 20° 6.577 4.297 30° 10.132 6.843 40° 13.368 9.043

[0045] The convex-plano lens 1 is continuously displaced by Δ2, and the plano-convex lens 2 is continuously displaced by Δ2-Δ1 at the same time, and the incident angle of sunlight θ changes continuously, such as Figure 8 As shown, sunlight tracking reception is achieved.

Claims

1. A sunlight collecting device composed of a plurality of sub-lens systems, characterized in that: The sub-lens system has a Galilean structure, and its components are a convex-planar lens (1), a plano-convex lens (2), and a biconcave lens (3) in order from the direction of sunlight incidence to the direction of sunlight emission. The spatial positions of the plane mirror surfaces of the convex-planar lens (1) and the plano-convex lens (2) coincide with each other. The convex mirror surface of the plano-convex lens (2) is separated from the incident concave mirror surface of the biconcave lens (3). The incident angle θ of the convex mirror surface of the convex-planar lens (1) is within the range of 0 to ±40°. The incident light enters the sub-lens system from the convex mirror surface of the convex-planar lens (1), and then is refracted twice by the plano-convex lens (2) and the biconcave lens (3) in sequence, and is emitted at an exit angle of 0°. The m×n sub-lens systems are combined to form a structure The sub-lens system array is formed, wherein the components of the sub-lens system array are, from the direction of sunlight incidence to the direction of sunlight emission, a convex-planar lens array (1S), a plano-convex lens array (2S), and a biconcave lens array (3S) in order; a subsequent condenser lens (4) is located on the light-emitting path of the sub-lens array; the subsequent condenser lens (4) and the biconcave lens array (3S) share a common optical axis and have the same aperture; the convex-planar lens array (1S) and the plano-convex lens array (2S) can be displaced in mutually perpendicular x directions or / and y directions, respectively; the x direction and the y direction are both perpendicular to the z direction where the common optical axis of the subsequent condenser lens (4) and the biconcave lens array (3S) is located.

2. The sunlight collecting device composed of a plurality of sub-lens systems according to claim 1, characterized in that: The aperture range of the sub-lens system is 1 to 12 mm, and the sub-lens system array is composed of m×n=3×3 to 9×9 sub-lens systems arranged in rows and columns.

3. The sunlight collecting device composed of a plurality of sub-lens systems according to claim 1, characterized in that: When receiving sunlight with an incident angle θ of 0°, the optical axes of the convex-planar lens (1), the plano-convex lens (2), and the biconcave lens (3) in the sub-lens system coincide with each other. When receiving sunlight with an incident angle θ of 0°<θ≦±40°, the convex-planar lens (1) moves by a distance Δ2 in the x direction or y direction perpendicular to the optical axis, and the plano-convex lens (2) also moves by Δ2-Δ1 in the same direction at the same time. The moving amplitude is smaller than that of the convex-planar lens (1). During the moving process, the optical axes of the convex-planar lens (1) and the plano-convex lens (2) form a distance Δ1. The corresponding relationship between Δ2 and θ is: Where: a1, b1 are the linear coefficient and quadratic coefficient of the convex-planar lens (1) respectively; The corresponding relationship between Δ1 and θ is: Wherein: a2, b2 are the linear coefficient and the quadratic coefficient of the plano-convex lens (2) respectively.

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