Lens, solar cell unit and joining method for a solar cell unit

Abstract

A lens, a solar cell unit including the lens and a joining method for the solar cell unit, wherein the lens has a main body with a substantially planar base, a receiving surface opposite the base, a side surface area connecting the base and the receiving surface and an optical axis extending perpendicular to the base and at least one bulge is arranged on the main body of the lens at a first height above the base on the side surface area.

Claims

1. A lens comprising: a main body with a substantially planar base, a receiving surface opposite the base, a side surface area connecting the base and the receiving surface; an optical axis extending substantially perpendicular to the base; and at least one bulge arranged on the main body of the lens within the side surface area between the receiving surface and the planar base, the at least one bulge having a bottom spaced from the base of the main body in a direction of the optical axis, wherein the at least one bulge covers an angular range of less than 130° of the circumference of the main body as measured from the optical axis, wherein, in a projection along the optical axis, a shadow of the main body has a first diameter, and wherein a shadow of the lens formed of the main body and the at least one bulge in a projection along the optical axis completely fits in a square having an edge length corresponding to the diameter.

2. The lens according to claim 1, wherein the lens has exactly two bulges or exactly three bulges or exactly four bulges.

3. The lens according to claim 1, wherein the lens has exactly four bulges, and wherein the four bulges are evenly or not evenly distributed along a circumference of the main body of the lens extending parallel to the base.

4. The lens according to claim 1, wherein the base of the main body has a diameter of at most 3 cm or at most 1.5 cm, and a height of the main body along the optical axis is at most 5 cm or at most 2 cm.

5. The lens according to claim 1, wherein a portion of the lens aligned with the base tapers towards the base so that the projection of the base along the optical axis is a smaller subsurface of the projection of the main body along the optical axis.

6. The lens according to claim 1, wherein the lens comprises a quartz glass compound and is formed integrally.

7. A lens comprising: a main body with a substantially planar base, a receiving surface opposite the base, a side surface area connecting the base and the receiving surface; an optical axis extending substantially perpendicular to the base; and at least one bulge arranged on the main body of the lens at a first height on the base on the side surface area, the at least one bulge having a bottom spaced from the base of the main body in a direction of the optical axis, wherein the at least one bulge covers an angular range of less than 130° of the circumference of the main body as measured from the optical axis, wherein, in a projection along the optical axis, a shadow of the main body has a first diameter, wherein a shadow of the lens formed of the main body and the at least one bulge in a projection along the optical axis completely fits in a square having an edge length corresponding to the diameter, and wherein the base of the lens has a circular shape, the receiving surface of the lens is convex, and the side surface area of the lens has a circular circumference.

8. A solar cell unit comprising: a lens according to claim 1; a semiconductor body constructed as a solar cell with a receiving surface, a base and at least two electrical contacts; and a support having a top and a bottom, wherein the base of the semiconductor body is electrically interconnected and frictionally connected to the top of the support, wherein the base of the lens is frictionally connected with the receiving surface of the semiconductor body via a polymer adhesive layer or a silicone compound.

9. The solar cell unit according to claim 8, wherein the top of the support is rectangular with four edges, wherein the lens has four bulges, and wherein the lens is arranged on the support such that a straight line connecting two opposing bulges case forms an angle between 35° and 55° towards edges of the support.

10. The lens according to claim 1, wherein the base of the lens has a circular shape.

11. The lens according to claim 1, wherein the receiving surface of the lens is convex.

12. The lens according to claim 1, wherein the side surface area of the lens has a circular circumference.

13. A lens comprising: a main body, comprising: a base having a planar bottom surface; a receiving surface opposite the base; and a side surface area connecting the base and the receiving surface; an optical axis extending perpendicular to the base; and a bulge arranged within the side surface between the receiving surface and the base at a first height, the bulge having a bottom spaced from the base in a direction of the optical axis, wherein the bulge covers an angular range of less than 130° of the circumference of the main body as measured from the optical axis, wherein, in a projection along the optical axis, a shadow of the main body has a first diameter, and wherein a shadow of the lens formed of the main body and the at least one bulge in a projection along the optical axis completely fits in a square having an edge length corresponding to the diameter.

14. The lens according to claim 1, wherein the lens is a single lens.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus, are not limitive of the present invention, and wherein:

(2) FIG. 1 is a schematic view of an exemplary embodiment of a lens according to the invention,

(3) FIG. 2 is a schematic plan view of the embodiment of the lens according to the invention,

(4) FIG. 3 is a schematic view of an exemplary embodiment of a solar cell unit having the lens according to the invention,

(5) FIG. 4 is a schematic view of an exemplary embodiment of a lens according to the invention, and

(6) FIG. 5 is a schematic view of am exemplary embodiment of a joining method.

DETAILED DESCRIPTION

(7) FIGS. 1 and 2 show a perspective view and a plan view of a first embodiment of a lens 10 according to the invention. The lens 10 consists of a main body 20 and four bulges 30, 32, 34, 36. The main body has a planar base 22, a convex receiving surface 24 opposite the base 22, and a cylindrical side surface area 26 with a height Z connecting the base 22 and the receiving surface 24, wherein an optical axis 28 of the main body 20 runs perpendicular to the base 22. The height Z is formed between a dotted auxiliary line and the base of the lens 10.

(8) All four bulges 30, 32, 34, 36 have the same shape and are arranged at a first height h1 above the base 22 on the side surface area 26. The four bulges 30, 32, 34, 36 are distributed uniformly around the circumference of the cylindrical side surface area 26 of the main body 20. The plan view of FIG. 2 shows that the bulges 30, 32, 34, 36 each protrude in a projection along the optical axis 28 beyond the main body 20. It should be noted that the height h1 is smaller than the height Z of the surface area 26.

(9) In the projection, the main body 20 has a circular outer contour with a diameter d1. The four evenly distributed bulges 30, 32, 34 and 36 are formed such in the illustrated embodiment that four evenly distributed bulges 30, 32, 34 and 36 augment the outer contour of the lens 10 in the projection to a square with rounded corners, wherein the one edge length k1 of the square is smaller than or equal to the diameter d1 of the main body 20. In this case, it should be noted that in the case of k1 smaller than d1, the square with the rounded corners has a circular segmental extension in the middle of each side surface due to the combination with the circular projection surface of the main body.

(10) The existing diameter d1 of the cylindrical side surface in the direction of the optical axis is of equal size, but it should be noted that in a non-illustrated embodiment, the diameter d1 of the cylindrical side surface increases or decreases in the optical axis direction.

(11) In the illustration of FIG. 3, a first embodiment of a solar cell unit 40 having a lens 10 is shown. In the following, only the differences from the illustrations of FIGS. 1 and 2 are explained. The solar cell unit 40 has a support 42 with a top 44 and a bottom 46. On the top 44, three contact surfaces 50, 52, 54 are arranged along a first edge 44.1. Between the contact surfaces 50, 52, 54 and a second edge 44.2 opposite the first edge 44.1, a semiconductor body 60 designed as a solar cell having a receiving surface 62 is arranged.

(12) The lens 10 shown in FIGS. 1 and 2 is frictionally connected to a receiving surface 62 of the semiconductor body 60 and a portion of the top 44 of the support 40 by means of a polymer adhesive layer 70 comprising a silicone compound, wherein the base of the lens is frictionally connected to the receiving surface of the semiconductor body by means of a polymer adhesive layer comprising a silicone compound.

(13) The lens 10 is arranged on the support 42 in such a way that the bulges 30, 32, 34, 36 of the lens 10 point in each case to a corner of the support 42 or that a straight line g1 connecting two opposing bulges 30 and 34 with the second edge 44.2 forms an angle of 45°.

(14) In the illustration of FIG. 4, a second embodiment of a lens 10 is shown. In the following, only the differences from the illustrations of FIGS. 1 and 2 are explained. The four bulges 30, 32, 34, 36 of the lens 10 have a semicircular upper part and a lower part 80 sloping down in the direction of the side surface area 26 of the main body 20 of the lens.

(15) Furthermore, the diameter of the projection of the convex lens portion 20 along the optical axis is greater than the diameter of the base 22 of the lens.

(16) In the drawing of FIG. 5, a first embodiment of a joining method for a solar cell unit 40 is illustrated. With an upwardly pointing base 22, the lens 10 is held positively on the four bulges 30, 32, 34, 36 in a holder. The polymer adhesive layer 70 is applied to the base 22 of the lens 10.

(17) A semi-finished product comprising the support 42 with the semiconductor body 60 and the three contacts 50, 52, 54 (not shown) is arranged such above the base 22 of the lens 10 covered by the polymer adhesive layer 70 that a centroid f1 of the base 22 of the lens 10 and a centroid f2 of a receiving surface 62 of the semiconductor body 60 are superimposed along the optical axis. Subsequently, the semi-finished product positioned above the lens 10 is approximated to the base 22 of the lens up to a defined gap size. The mount of silicone and the gap size are selected such that the silicone completely or at least partially fills the gap between the base 22 of the lens and the semi-finished product.

(18) According to the embodiment shown in FIG. 4, the main body 20 of the lens tapers towards the base 22 of the main body.

(19) The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are to be included within the scope of the following claims.