Abstract: An F? lens for infrared large-format telecentric laser marking is disclosed, including a first lens element, a second lens element, a third lens element and a fourth lens element arranged sequentially along the propagation direction of an incident ray. The first lens element is a negative biconcave lens element including a first curved surface and a second curved surface. The second lens element is a positive meniscus lens element including a third curved surface and a fourth curved surface. The third lens element is a positive meniscus lens element including a fifth curved surface and a sixth curved surface. The fourth lens element is a plane lens adapted to play a role in protecting other lens elements. The first to third lens elements are arranged around a same axis along the propagation direction of the incident ray. The first to sixth curved surfaces are arranged sequentially along the propagation direction of the incident ray.

Abstract: An F? lens for infrared large-format telecentric laser marking is disclosed, including a first lens element, a second lens element, a third lens element and a fourth lens element arranged sequentially along the propagation direction of an incident ray. The first lens element is a negative biconcave lens element including a first curved surface and a second curved surface. The second lens element is a positive meniscus lens element including a third curved surface and a fourth curved surface. The third lens element is a positive meniscus lens element including a fifth curved surface and a sixth curved surface. The fourth lens element is a plane lens adapted to play a role in protecting other lens elements. The first to third lens elements are arranged around a same axis along the propagation direction of the incident ray. The first to sixth curved surfaces are arranged sequentially along the propagation direction of the incident ray.

Abstract: A street light includes a post with a light bulb connected to a top thereof and a wind power generator unit is connected to the post and includes a shaft, a plurality of blades connected to the shaft, and a generator connected to the shaft. A chargeable battery is electrically connected to the generator and the light bulb. A circuit board is electrically connected to the chargeable battery and the light bulb.