A depolarizer or depolariser is an optical device used to scramble the polarization of light. An ideal depolarizer would output randomly polarized light whatever its input, but all practical depolarizers produce pseudo-random output polarization.

What is the function of depolarizer?

In the battery industry, the term "depolarizer" has been used to denote a substance used in a primary cell to prevent buildup of hydrogen gas bubbles. A battery depolarizer takes up electrons during discharge of the cell; therefore, it is always an oxidizing agent.

What is depolarizer in dry cell?

In the dry cell, manganese dioxide is used as depolarizer. It prevents the collection of hydrogen gas on the cathode.