Lens, light emitting device and backlight module

摘要

A lens includes a light incident surface and a light output surface. The light incident surface includes a first region having points equidistant from the central point of a light emission surface of the light emitting element. The first region satisfies θa≦θ1≦θb, wherein θ1 is a first incident angle of any light emitting from the light emitting element. In a second region with 0°<θ1≦θb+20°, the first incident angle of light having a minimum value of θ2/θ1 is between θa and θb, and θ2/θ1>0.9. In a third region with 0°<θ1≦θb+10°, the first incident angle of light having a minimum value of θ3/θ1 is between θa and θb, and θ3/θ1>0.9. θ2 is a second incident angle of the light of θ1 when traveling in the lens, and θ3 is a third incident angle of the light of θ1 when emitting out of the lens.

主权项

1. A lens for controlling light emitting from a light emitting element, comprising:
a light incident surface configured for entrance of the light emitting from the light emitting element into the lens, the light incident surface comprising a first region having points equidistant from a central point of a light emission surface of the light emitting element, the first region satisfying θa≦θ1≦θb, wherein θ1 is a first incident angle of any light emitting from the light emitting element, θa is the minimum value of the first incident angle in the first region, and θb is the maximum value of first incident angle in the first region; and a light output surface facing the light incident surface and configured for radiation of the light from the light emitting element out of the lens; wherein the light incident surface and the light output surface satisfy the following conditions (1) and (2): condition (1): in a second region of the light incident surface satisfying 0°<θ1≦θb+20°, the first incident angle of light which emits from the light emitting element and has a minimum value of θ2/θ1 is in a range from θa to θb, and θ2/θ1>0.9, where θ2 is a second incident angle of the light of θ1 when traveling in the lens; and condition (2): in a third region of the light incident surface satisfying 0°<θ1≦θb+10°, the first incident angle of light which emits from the light emitting element and has a minimum value of θ3/θ1 is in a range from θa to θb, and θ3/θ1>0.9, where θ3 is a third incident angle of the light of θ1 when emitting out of the light output surface.