SIGMAKOKI Spherical biconcave lens, anti-reflection coating (400-700nm) type, SLB series

This lens can refract light efficiently in a small space by making both sides concave, and spread the light widely. It can be used to expand the irradiation area of the illumination light. This lens is made of BK7 for the visible to near infrared range. We offer three types of lenses with anti-reflection coating: visible, near infrared, and infrared. You can select the lens that suits your specifications from a wide variety of variations subdivided by outer diameter size and focal length. *A concave lens cannot collect light or form a real image by itself. *Please use it in combination with a convex lens. *Spherical biconcave lenses have chromatic aberration, and the focal length changes depending on the wavelength. *When using a high-energy pulse laser, the reflected light from the concave surface may form a focal point on the light path, causing sparks. *Please use a plano-concave lens when using a pulse laser.