• Fabricated from N-BK7
• Reflects an Inverted and Reversed Image 180°
• Ø50 mm, L = 42 mm
• 650-1050 nm (-B Coating)

This Thorlabs' retroreflector is a trihedral prism manufactured from a solid piece of N-BK7 glass. Commonly referred to as a corner cube, the prism is unmounted, has a 50 mm diameter and has an AR coating for the 650 - 1050 nm range.

Via three total internal reflections (TIR), an image or beam is reflected back towards its original direction. The beam or image will be reflected through 180° even if the angle of incidence is not zero. The insensitivity of the alignment of the prism makes it an ideal retroreflecting optic. For these retroreflecting prisms, the incident and reflected beams will be parallel to within 3 arcmin. However, unless the incident and reflected beams strike the exact center of the optic, they will not overlap but rather be shifted with respect to each other. For example, if the incident beam strikes the optic 3 mm to the right of center, the retroreflected beam will emerge 3 mm to the left of center.

• Material: N-BK7 Grade A Fine Anneal
• Clear Aperture: 70% of Area
• Surface Flatness: λ/10 @ 633 nm
• Surface Quality: 40-20 Scratch-Dig
• Beam Deviation (Between Incident and Reflected Beams): <3 arcmin
• Design Wavelength: 633 nm