It’s not that the Indian Army has not been trying. Starting in 2001, and for five years after that, Indians struggled with the French Catherine thermal imagers installed in their new T-90 tanks. Thermal imaging forms a picture based on the heat it detects. Thus it can see through dust storms and fog and spot warm bodies and vehicle engines. This is the most effective form of night vision (as opposed to light enhancement and infrared illumination).
With the problems fixed in the first 600, India has bought another 400 Catherine Thermal Imaging systems in 2008. The Catherine FC thermal imaging cameras are built by electronics manufacturer Thales, whose thermal imaging systems are popular in the United States as well. The U.S. Marine Corps recently bought thermal imaging binoculars from Thales. India was a special case because there were severe heat problems with their Catherine sights, which explains why India turned to the Israeli TIFACS (thermal fire control systems) for upgrading several thousand T-72s. India has already bought thousands of smaller Israeli thermal devices for the infantry. The Israeli thermal devices are built more with heat problems in mind.
Previously, only aircraft and tanks could carry the bulky thermal imaging equipment. But over the last decade, new technology has made it possible to build one kilogram (2.2 pound) thermal imaging rifle scopes. There are also thermal binoculars can detect large vehicles up to 10 kilometers or more (and individuals at about half that distance). In a place like northern India, you can keep an eye on a large area, as enemy troops cannot hide the heat their bodies produce. India has a lot of fog and mist that normally hides a lot of activity, as well as frequent dust storms. The larger thermal imagers, like those used in tanks, have about the same range as the binoculars but show more detail and cost about five times as much.
The Indian Army also wants to buy more thermal sights for rifles and machine-guns as well, for helicopter pilots.