Scientists have long known that you can pick up ELF transmission by laser light. You can use the laser to see the Extremely Low Frequencies spreading out like ripples in a pond. In the future as the entire spectrum of the battlespace is filled with communication waves throughout the spectrum in the net-centric future warfare scenario, it will be important to detect the enemies communications. If the enemy goes to a very low frequency or an extremely low frequency for communication to avoid the other bands and to attempt to conceal himself and remain undetected then perhaps a laser light in a spectrum that the human eye cannot see can be pointed around at the suspected positions of the enemy to see if there are waves moving from the electromagnetic field of such devices.

Since human brain waves also emit from the body on these frequencies perhaps a person or sniper sitting behind a wall can be detected using laser light. So even though you cannot see him you can see the energy emission of him and this you simply put a high explosive round thru said wall eliminated said sniper and saving your own soldiers lives, as your enemy gives up his for thinking he could outwit your blue force in your mission to make the world free. Think on this.