TECHSPEC® N-BK7 Corner Cube Retroreflectors are designed to reflect any ray or beam entering the prism face, regardless of the orientation of the prism, back onto itself. A mirror will do that only at the normal incidence. As a result, corner cube retroreflectors are useful where precision alignment is impossible or time-consuming. TECHSPEC® N-BK7 Corner Cube Retroreflectors are available with the dihedral surfaces either uncoated or coated with silver. The silver coating provides a larger acceptance angle while the uncoated option, which relies on total internal reflection, provides optimum reflectivity. The input face is available uncoated or coated with an antireflection coating optimized for either visible wavelengths or near infrared wavelengths, including 1064nm and 1550nm.