What brand of polarizer is bw?

B+W Filter Company is a subsidiary of Schneider Company in Germany, and its products are outstanding in the field of multi-layer coating (MRC). In order to achieve perfect optical quality and strict requirements from top photography manufacturers, all the lens glass raw materials of B+W filter come from Schott glass, which is one of the best German optical glass manufacturers in the world. The production line of B+W is strictly controlled by computer, and the lens surface is treated by high-end vacuum coating equipment. From design to final inspection, the manufacturing process of each stage is strictly controlled to ensure the complete presentation of optical image quality. The food is good, but it's too expensive.