What is the difference between aspherical lenses and ordinary lenses?

Spherical lenses are used to focus, form images, and collimate or expand light. We offer a variety of lens shape, material and lens quality options so you can find the right balance between performance and cost for even the most demanding applications. Typically, our spherical lens catalog is inspired by laser applications, focusing on high quality and high damage threshold materials. All products are available with user-specified high-durability, low-loss antireflection coating. Whatever your application, we can help you perform ray tracing analysis on a simple catalog component system, and we can guide you in selecting the right model or custom lenses based on your needs. Regarding spherical lenses, we mainly provide the following models.

Plano-convex spherical lenses are used to converge or focus light, and to collimate point sources of light. Cost-effective alternative to positive lenses when used with infinite conjugate ratio, collimating light incident on a convex surface. Reduces spherical aberration and near-zero coma when used off-axis.

Biconvex spherical lenses are used in 1:1 imaging, beam expander and beam relay applications. Good positive lenses for virtual imaging of real objects and positive conjugate image ratios from about 0.2 to 5 (depending on wavelength). Can also be used for lower f-number focusing applications. When used at unit conjugate ratio, it behaves like an optimal single lens.

Plano-concave spherical lenses are used to expand light or increase focal length in an optical system, or to balance the aberrations of other lenses within the system. Negative focal length causes collimated incident light to diverge. When collimated light is incident on the concave side at an infinite conjugate ratio, spherical aberration and coma are reduced.

Biconcave spherical lenses are used to diverge or expand light in laser beam expanders, optical character readers, viewers and projection systems. Negative focal length; creates a virtual image that can be seen through the lens.

Aspherical IR Lenses (Condenser Lenses) For light collection applications requiring low cost positive lenses. Reduce aberrations for low f-number, high-throughput use. Not recommended for imaging, precision focus, or high power applications.