Flashed opal offers a more thorough diffusion with a distribution close to Lambertian, with the brightness of the diffuser being independent of the viewing angle.
Such wide scattering angles will inevitably reduce brightness, however Opal diffusers can be very useful in light boxes and other illumination systems.
Note: Flashed opal diffuser material has been discontinued by the manufacturer. Knight Optical still hold limited stock parts available for purchase. Please contact our sales team for more information.