Difference Incidence Orientation for Optical Filters
Share
Facing the coated side of the filter toward the light source can reduce unwanted scattering and minimize the amount of reflected light returning to the source.
However, using the filter in the reverse direction does not significantly affect its performance.
The figure below shows the measured transmission versus wavelength under low-intensity broadband illumination. The difference between the forward and reverse transmission curves is minimal, which may result from a slight variation in the incident angle when the filter was moved, flipped, or replaced.
