Infrared sensors face a problem: because they operate by detecting heat, the sensor itself generates enough heat at room temperature that the target signal is lost in noise. Trying to detect a distant heat source with a warm detector is like trying to see a candle next to a bonfire.
The solution to this problem is cooling the sensor to a very low temperature, around minus 196 degrees Celsius. At such a cooling, the sensor's own noise decreases, and the weak signal becomes discernible. Creating such a device, which must be small, light, and immediately ready for use, presents a complex engineering challenge.
The startup Techno Defence solved this problem. The company is based in Mumbai, and its office and laboratory complex is located in Thane. It has attracted the attention of high-ranking military officials, including the chairman of DRDO and the founder of BrahMos Aerospace. They have developed a miniature Joule-Thomson type cryocooler—a device that cools by expanding high-pressure gas through an orifice, which sharply lowers its temperature.
The device weighs approximately ten grams. It has a two-flow, self-regulating design created in collaboration with the DRDO Solid State Physics Laboratory in Delhi under the Technology Development Fund. This fund supports Indian companies engaged in defense technologies.
Work on the project began around 2017 or 2018 and was supervised by Dr. Pravin Salinkar, an IIT Bombay graduate and former director of the DRDO laboratory. Funding from the Technology Development Fund was received in 2020. The cryocooler was completed in 2023 or 2024 and handed over to DRDO for evaluation.
Testing was deemed successful. Instead of building large-scale infrastructure, the company developed its own manufacturing methods and equipment, using small and artisanal production for part of the process. Assembly is performed under microscopes, in sterile conditions meeting reliability standards for defense needs, by a small team, most of whom are women.
Cooled infrared detectors are used in guidance systems that locate and track targets. Although not all types of weaponry require such detectors, such as satellite-oriented systems, the cryocooler is indispensable for infrared-guided systems, and historically, the technology came only from a few suppliers.
The importance lies not so much in the device itself, but in what it replaces. A subsystem of this kind, acquired abroad, comes with export licenses, delivery schedules set by a third party, and the possibility of supply cessation. Furthermore, it changes the economics of the systems in which it is integrated. A component available only from one foreign supplier has a corresponding price, whereas a domestic alternative revises this cost for every program using that component.
This breakthrough attracted public attention after industrialist Anand Mahindra noted it, highlighting the small size of the team and the duration of work on one complex task. Techno Defence states that its broader goal is the development of cryocooling technologies and the creation of cost-effective solutions for guidance systems, as well as working with young engineers on new developments. Its lab in Thane has been visited by high-ranking military leaders, including the chairman of DRDO and the founder of BrahMos Aerospace. However, the commercial position remains confidential: no orders, contract values, production volumes, or revenue have been disclosed, and besides support from the Technology Development Fund, no other funding sources appear in any reports.
