Offering 92% transmission from 350 to 2,000 nm, TECHSPEC OD 6 Rugate notch filters are manufactured using single coating layer with continuous sinusoidally varying refractive index. Units have low ripple of less than 5% and no harmonic reflections, making them suited for broad range of wavelengths. Mounted in black anodized aluminum ring for integration into optical systems, all models have 25 mm dia, 2.54 mm thickness, and clear 22 mm aperture.