Most photomasks are created by etching away a thin film of light-blocking chrome from the surface of a quartz plate.

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A. had a map light on a chrome stem, and quivering dials.

NEWYORKER: Hand on the Shoulder

This impression is reinforced by the curvature of the rear window and the elegant chrome strip between the rear light clusters.

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First, just a glint of chrome radiator, a spark of light where the road bled itself into plowed field.

NEWYORKER: The Tree Line, Kansas, 1934

Where the chrome is etched away, the light can get through.

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Dissatisfied with the soft steel pitons used by other climbers, he taught himself blacksmithing and created a spike of chrome nickel steel so strong and light that it fundamentally changed the sport.

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To further hone the image, engineers use a technique called optical proximity correction, which uses oddly shaped bars, notches and other distortions that are cut into the chrome template on the quartz plate to trick light waves into making a more precise pattern (see left).

FORBES: Trick Of The Light

To further hone the image, engineers use a technique called optical proximity correction, which uses oddly shaped bars, notches and other distortions that are cut into the chrome template on the quartz plate to trick light waves into making a more precise pattern (see chart).

FORBES: Trick of the Light