Projector Meniscus Lens Two refracting surfaces of optical lens are both spherical or one is spherical and the other is flat.  Worldhawk can supply standard and high-precision spherical lens in a variety of shapes, sizes, focal lengths on a wide spectrum. The structure of lens can be Plano-convex, Plano-concave, Bi-convex, Bi-concave, Meniscus. They are widely used in medical, industry, spaceflight andmilitary etc.. Convex Lenses are ideal for light collimation or for focusing applications utilizing monochromatic illumination, in a range of industries including industrial, pharmaceutical, robotics, or defense. Concave Lenses are optical lenses with a negative focal length.  Concave Lenses are ideal for beam expansion, light projection, or for expanding an optical system’s focal length. Specification of Projector Meniscus Lens Materail Optical glass, Fused Silica, Optical crystal.  Diameter Tolerance +/-0.1mm, +/-0.05mm Center Thickness Tolerance +/-3', +/-1', +/-30''  Focal Length Tolerance Upon costomer requirement.  Clear Aperture >90% Surface Quality(S/D) 60/40,40/20 or better Chamfer 0.1~0.3mm x 45degree Coating R/AR