Where to Buy Lenses

• Are they available with the required focal length?
• Have you checked whether the lens should be biconvex, plano-convex, plano-concave, biconcave, or a meniscus or doublet lens?
• Is the numerical aperture sufficiently large?
• Is the optical quality high enough? Consider surface quality (e.g. scratch & dig) and wavefront distortions.
• Can you use simple spherical surfaces, or do you need aspheric optics, possibly with freeform surfaces?
• Do you need achromatic lenses for operation in wide wavelength ranges?
• Do you need anti-reflection coatings? Broadband or high-performance narrowband?
• For high-power applications: are there thermal effects due to parasitic absorption? How about the optical damage threshold?
• How to mount the lenses? Is the holder suitable for application with high-power beams (even if they are misaligned)?

In case that you need additional advice, consultancy from RP Photonics may be the solution.