Resumen
The present invention relates to a lens having limited chromatic aberration for photovoltaic concentrators comprising a doublet formed by two individual lenses, a first individual rigid diverging lens and a second individual converging lens, where the material of the first individual diverging lens has greater dispersion than the material of the second individual elastomeric converging lens, and further comprising a transparent rigid support extending essentially in a principal plane perpendicular to the focal axis of the doublet of individual lenses. The elastomer occupies the space between the first individual rigid diverging lens and the rigid support.
Reivindicaciones
1. A lens having limited chromatic aberration for photovoltaic concentrators comprising a doublet formed by two individual lenses, a first individual diverging lens (4) and a second individual converging lens (3), where the material of the first individual diverging lens (4) has greater dispersion than the material of the second individual converging lens (3), characterized in that: - it additionally comprises a transparent rigid support (2) extending essentially in a principal plane perpendicular to the focal axis of the doublet of individual lenses (3, 4); - the first individual diverging lens (4) is rigid; and, - the second individual converging lens (3) is formed by an elastomer occupying the space between the first individual diverging lens (4) and the rigid support (2). 2. The lens (1) according to claim 1, characterized in that the first individual diverging lens (4) has a Fresnel configuration on the surface in contact with the second individual converging lens (3). 3. The lens (1) according to claim 1 or 2, characterized in that the first individual diverging lens (4) has a Fresnel configuration on the surface opposite the surface in contact with the second individual converging lens (3). 4. The lens (1) according to claim 1, characterized in that the rigid support (2) is a flat plate, preferably a sheet of transparent plastic or glass. 5. The lens (1) according to any of the preceding claims, characterized in that the first individual diverging lens (4) is made of polycarbonate, PC, or polymethyl methacrylate, PMMA. 6. The lens (1) according to any of the preceding claims, characterized in that the second individual converging lens (3) is made of optically transparent silicone or ethyl vinyl acetate. 7. A compound lens comprising a plurality of lenses (1) according to any of the preceding claims distributed in a plane, where the rigid support (2) is a common support in the plurality of individual lenses (1). 8. A compound lens comprising a plurality of lenses (1) according to any of the preceding claims distributed in a plane, where the plurality of first individual diverging lenses (4) are configured in one and the same part. 9. A method of manufacturing a lens having limited chromatic aberration for photovoltaic concentrators comprising the following steps: a) providing a first individual rigid diverging lens (4); b) providing a support (2) extending essentially in a plane perpendicular to the focal axis of the individual rigid diverging lens (4); c) providing an elastomer capable of being, at least once, in a first state in liquid conditions and of being in a second state in a solid condition; d) incorporating the elastomer in the first state in liquid conditions in the space defined between the first individual rigid diverging lens (4) and the support (2) such that said elastomer occupies the space between the first individual diverging lens (4) and said support (2) in at least one region of the support (2); e) causing the elastomer to change from the first state in liquid conditions to the second state in a solid condition. 10. The method according to claim 9, wherein the first individual rigid diverging lens (4) of step a) is obtained by plastic molding. 11. The method according to claim 10, where the plastic molding is performed by injection, hot embossing or thermal roller embossing. 12. The method according to claims 9 to 11, wherein the elastomer of step c) is a liquid elastomer that allows a curing reagent, giving rise to a state in solid conditions. 13. The method according to claim 12, wherein the elastomer, preferably silicone, is mixed with the reagent before step d), and step e) is brought about by means of curing the elastomer. 14. The method according to claim 13, wherein the elastomer is cured in an oven by heating the elastomer above room temperature and below the degradation temperature of the material of the individual rigid diverging lens (4). 15. The method according to claims 9 to 11, wherein the elastomer of step c) is a solid elastomer, preferably ethyl vinyl acetate, that melts when the temperature is raised; and where the elastomer is incorporated in step d) in the first liquid state according to the following steps: - arranging the solid elastomer in the space defined between the first individual rigid diverging lens (4) and the support (2), - raising the temperature of at least the solid elastomer to at least its melting temperature; and where step e) is carried out by cooling the elastomer below its melting point. 16. The method according to claim 15, wherein in addition to raising the temperature of the elastomer above the melting temperature, a vacuum is applied to remove air bubbles in the elastomer. 17. The method according to claim 15 or 16, wherein in addition to raising the temperature of the elastomer above the melting temperature, a force for bringing the support (2) and the first individual diverging lens (4) closer together is applied. 18. The method according to any of claims 9 to 17, wherein the support (2) is - either a transparent rigid support, - or a transparent sheet which additionally has a rigid support that can be removed after step e).
