summary:
A spherical lens has a constant curvature from the center to the edge of the lens, rather than a sphere, while a lens has a continuous change in curvature from the center to the edge. In order to ensure the optical performance of photographic lens, many "aberrations" must be corrected. If only a spherical lens is used for correction, many lens combinations are required according to the technical requirements of the corresponding lens. For special high-end lens, only spherical lens can not correct the aberration to the satisfaction of users
A spherical aberration calibrationOptical lens manufacturer
Aspherical lens is used to replace spherical lens. Its remarkable advantage is that it can correct the spherical aberration caused by spherical lens in collimation and focusing system. By adjusting the surface constant and aspherical coefficient, the aspherical lens can Zui greatly eliminate the spherical aberration. Aspherical lens (light converges to the same point to provide optical quality) is basically eliminated, except for the spherical aberration generated by spherical lens (light converges to different points, resulting in blurred imaging).Optical lens manufacturer
Three spherical lenses are used to increase the effective focal length for eliminating spherical aberration. However, an aspheric lens (high numerical aperture, short focal length) can be realized, which simplifies the system design and provides light transmittance.Optical lens manufacturer
B system advantages
Aspherical lens simplifies the elements involved by optical engineers in order to improve the optical quality, and improves the stability of the system. For example, in a zoom system, usually 10 or more lenses are used (additional: high mechanical tolerance, additional assembly procedures, and improved antireflection coating). However, one or two aspheric lenses can achieve similar or better optical quality, so as to reduce the system size, improve the cost rate, and reduce the overall cost of the system.
