Aspheric lenses can improve image quality and correct imaging problems usually associated with spherical lenses. The original work and function of the aspheric lens are mainly reflected in the following aspects:
In a spherical lens, light is focused at different distances (depending on where it enters relative to the edge of the lens), which can cause blur and peripheral distortion. This phenomenon is called spherical aberration.
Aspheric lenses advantages: aspherical lenses can reduce or eliminate this problem due to its unique design (with a shallower surface curvature angle). When light enters the aspheric lens, whether it enters or not, it will be focused to a point, resulting in a clearer and sharper image.
When spherical lenses zoom in or zoom out an image, they will distort and bend the lines viewed through them. Since the edge power of the aspheric lens is low, the risk of pincushion distortion of the positive lens and barrel distortion of the negative lens can be reduced or eliminated.
Edge astigmatism refers to the unnecessary power gain that occurs in spherical and cylindrical mirrors when observing something from the optical center. It helps to create blurred images. Aspheric lenses avoid this situation by reducing the power gain along the edge of the lens.