The L-40X Infinity Corrected Objective Lens is designed with the rear conjugate at infinity and is ideal for use as an input lens in collimating applications when optimum wavefront quality is required. The L-40X is a 40X objective with a 0.66 numeric aperture, a 8.0 mm clear aperture and a focal length of 4.6 mm. It uses a standard RMS thread, 0.800-36.