Edmund Optics Inc. 20mm Diameter, 1/4 Wave N-BK7 Window, 405nm V-Coat NT64-040

<0.25% Reflection at Design Wavelength Coatings Available for HeNe and Nd:YAG Laser Sources Precision N-BK7 Substrate Also Available Uncoated, MgF2 Coated and VIS 0° Coated TECHSPEC® 1/4λ N-BK7 Laser-Line Windows are ideally suited for industrial and low power laser applications. The high tolerance design yields minimal beam distortion and scatter. Anti-reflection coatings provide <0.25% reflection at the coating's design wavelengths.