The lens can be used for control the light source to become more concenting to increase efficacy.
We also have lens for spread the light to different beam angle.  Speification below for reference.

Sometimes you need window or filter as a cover out of device to improve, eliminate, cut-off transmission.
We could provide custom window or filter in different material with particular function for apply in your products.
Any technical discussion or questions, please contact our support.

The microlens array are for distribute light to plane and improve the uniformity on a plane, ex: light projection,
UV exposure system.  Most of our lens are custom design after discuss all specification with our customers.