| 摘要 |
A lens, a lens system and applications thereof. The lens (1) comprises a front surface (2), a rear surface (3), and a side surface (4) extending between the front surface (2) and the rear surface (3). The rear surface (3) defines a cavity (5) facing a rear portion. The front surface (2) comprises a central surface (201) and an edge surface (202) surrounding and connected to the central surface (201). The edge surface (202) extends between the central surface (201) and the side surface (4). The lens (1) is an axisymmetric body, and defines a central axis (6). The lens (1), in combination with an LED light source (7) and/or a similar light source disposed on the central axis (6) and capable of moving in the cavity, forms the lens system. The high utilization rate of emergent light of the light source is realized, and collimation and focusing of incident light are realized. The lens system can be used in a flashlight with a focusing function. |
