What is the difference between B+W Kjeldahl multilayer ultra-thin polarizer and multi-film ultra-thin polarizer in photography?

B+W kjeldahl polarizer. The polarizing film is sandwiched between two ultra-thin hyperplane optical glasses, which enables it to realize higher precision parallel plane processing technology. The edges of the glass and polarizing film are sealed and protected to prevent the influence of moisture. Suitable for users who have the highest requirements for image quality.

There will be no dispersion phenomenon of long focal length and large aperture lens when using Kjeldahl polarizer.