Polaroid

In the simplest form of this system, applicable to many microscopes, the substage polar consists only of semicircles of polaroid orientated to give respective planes of polarisation at right angles. Polaroids over the eyepieces are orientated so extinguish the inner halves of the exit pupils.

If there is no sample in the cell, and the second polaroid is rotated until it is at right angles to the first, the observer will see no light.

Polaroids are used as window screens to regulate the amount of light entering the room.

She went to see BWANA DEVIL and, after donning the polaroids, saw correctly.

[…]I discovered my old woggle in a cardboard box, together with my Herald Learn-To-Swim certificate (25 yards without touching the bottom), a copy of the Eltham High School magazine and a pair of polaroids I pinched from a 3-D screening of Bwana Devil in 1953.

One reel, loaded with a floating or intermediate line, a few braided leaders of varying sinking-rates, a few spare spools of leader-material in 6, 8 and 10lb breaking-strain, a box of assorted fly-patterns, a good pair of polaroids to stop the glare and to protect eyes, and a collapsible line-tray as the rocks are very sharp and soon ruin lines.

For while the boy continued to sport his pair of Polaroids, evidently the brilliant afternoon had broken into a drizzle: his damp cargo pants and t-shirt clung to his thin but well-muscled torso while his olive-skinned arms and face appeared as if sugar glazed.

I could carry a spare pair of polaroids; however, Steve usually carries an extra pair which should be sufficient back-up for both of us.