Lens with elongated radiation pattern
View Patent ↗A lens comprises an elongated shape. The lens has a short axis and a long axis. The lens comprises an upper surface through which a substantial majority of light exits the lens when a light emitting element is situated at or below a base of the lens. The upper surface includes a trough that extends along at least one of the short and the long axis. The upper surface includes a surface of a curved wall that joins the upper surface to the base of the lens. A lower surface of the trough is curved along the short axis and along the long axis. The lower surface of the trough has a curvature along the short axis that differs from a curvature along the long axis.
1. A lens, comprising:
an elongated shape, the lens having a short axis and a long axis; and
an upper surface through which a substantial majority of light exits the lens when a light emitting element is situated at or below a base of the lens,
the upper surface including a trough that extends along at least one of the short and the long axis;
a lower surface of the trough being curved along the short axis and along the long axis,
the lower surface of the trough having a curvature along the short axis that differs from a curvature along the long axis.
2. The lens of claim 1 , wherein the upper surface includes a surface of a curved wall that joins the upper surface to the base of the lens.
3. The lens of claim 1 , further comprising a recessed portion that intersects a periphery of the trough.
4. The lens of claim 1 , further comprising one of a raised portion or a recessed portion within the trough.
5. A method for providing illumination, the method comprising:
generating light with a light-emitting element; and
redirecting the light with a lens,
the lens having a base that faces the light-emitting element,
the lens having an upper surface, opposite the base, that faces away from the light-emitting element,
the lens having a perimeter that is elongated along a long axis,
the upper surface of the lens including an indentation that is elongated generally along the long axis,
the indentation having a curved lower surface that has a first curvature generally along the long axis and a second curvature, different from the first curvature, generally orthogonal to the long axis.
6. An illuminator, comprising:
a light-emitting element; and
a lens configured to redirect light emitted from the light-emitting element,
the lens having a base that faces the light-emitting element,
the lens having an upper surface, opposite the base, that faces away from the light-emitting element,
the lens having a perimeter that is elongated along a long axis,
the upper surface of the lens including an indentation that is elongated generally along the long axis,
the indentation having a curved lower surface that has a first curvature generally along the long axis and a second curvature, different from the first curvature, generally orthogonal to the long axis.
7. The illuminator of claim 6 , wherein the perimeter of the lens is substantially elliptical and the indentation has a perimeter is substantially elliptical.
8. The illuminator of claim 6 , wherein the upper surface of the lens includes a curved wall that joins the upper surface of the lens to the base of the lens.
9. The illuminator of claim 6 , wherein the upper surface of the lens further includes a recessed portion that intersects a periphery of the indentation.
10. The illuminator of claim 6 , wherein the curved lower surface of the indentation further includes a raised portion within the indentation.
11. The illuminator of claim 6 , wherein the curved lower surface of the indentation further includes a recessed portion within the indentation.
12. The illuminator of claim 6 , wherein the light-emitting element includes a single light emitting diode.
13. The illuminator of claim 6 , wherein the light-emitting element includes multiple light emitting diodes.
14. The illuminator of claim 6 , wherein the lens is formed from a material having a refractive index between about 1.4 and about 2.2 at a wavelength of light emitted by the light-emitting element.
15. The illuminator of claim 6 , wherein the lens is formed from at least one of a specified plurality of material classes, the plurality of material classes including epoxy, silicone, sol-gel, and glass.
16. The illuminator of claim 6 , wherein the perimeter of the lens is substantially oval.
17. The illuminator of claim 6 , wherein the indentation has a perimeter is substantially oval.
18. The illuminator of claim 6 , wherein the perimeter of the lens is substantially oval and the indentation has a perimeter is substantially oval.
19. The illuminator of claim 6 , wherein the perimeter of the lens is substantially elliptical.
20. The illuminator of claim 6 , wherein the indentation has a perimeter is substantially elliptical.