LDR

Landauer, Inc.

A maker of radiation dosimeters—small badges that workers in hospitals, nuclear plants, and research labs wear to track their radiation exposure. Founded in 1954 by Robert S. Landauer Jr., the company began in the utility room of his Illinois home, serving three Chicago-area hospitals. Its badges use aluminum oxide crystals that trap energy when exposed to radiation, and the company is named after its founder, whose father was a pioneering X-ray physicist.