What is the function of a lens?

[OVivian]

Here are the functions of a lens: 1. Road illumination: Due to its strong light-gathering ability, using a lens for road illumination not only makes the road surface bright but also clear; 2. Long-range and clear illumination: Since the light dispersion is minimal, the light range of a lens is farther and clearer than that of a conventional halogen lamp; 3. Strong penetration: Compared to traditional lamp headlights, lens-type headlights have uniform brightness and strong penetration. Below is additional information about lenses: 1. Single-beam lens: This type has only one beam—low beam, typically using a halogen or xenon bulb. Single-beam lenses are designed with corresponding lenses for low and high beams. The difference with a dual-beam lens is that it can switch between high and low beams, usually staying in the low-beam state; 2. Dual-beam lens: It is a single lens that can switch between high and low beams by adjusting the internal shutter. When the shutter is closed, it emits a low beam, and when the shutter is open, it emits a high beam.