Teledyne Technologies Inc sells technologies for industrial markets. Roughly a fourth of Teledyne's revenue comes from contracts with the United States government. The firm operates in four segments: instrumentation, digital imaging, aerospace and defense electronics, and engineered systems. The instrumentation segment contributes the largest proportion of revenue and provides monitoring instruments primarily for marine and environmental applications. The digital imaging segment includes image sensors and cameras for industrial, government, and medical customers. The aerospace and defense electronics segment provides electronic components and communication products for aircraft. The engineered systems segment provides solutions for defense, space, environmental, and energy applications.