Because the atmosphere is quite transparent to infrared light, CO2 lasers are also used for military rangefinding using LIDAR techniques.

[2] Patel joined Bell Laboratories in 1961, and subsequently became Executive Director of the Research, Materials Science, Engineering and Academic Affairs Division at AT&T Bell Laboratories in Murray Hill, New Jersey, where he developed the carbon dioxide laser.

Patel's discovery, in 1963, of the laser action on the rotational–vibrational transitions of carbon dioxide and his discovery, in 1964, of efficient vibrational energy transfer between molecules, led to a series of experiments which demonstrated that the carbon dioxide laser was capable of very high continuous-wave and pulsed power output at very high conversion efficiencies.

[3] In 1996, President Bill Clinton awarded Patel the National Medal of Science, "[f]or his fundamental contributions to quantum electronics and invention of the carbon dioxide laser, which have had significant impact on industrial, scientific, medical, and defense applications.

[10] In 2018 C. Kumar N. Patel became an Honorary Member of the American Laser Study Club[11] which a year later named an award in his honor.