Electrochemically deposited gold gives 98% reflectance in the infrared. The parabolic reflector is a key component employed in the TOW antitank missile guidance system. |
An infrared guidance-beacon reflector for the Tube launched, Optically tracked, and Wire guided (TOW) antitank missile is now made from die-cast aluminum that's electrochemically gold coated.
The 25-mm parabolic reflector is the heart of the TOW missile tracking system. Epner Technology Inc., Brooklyn, N.Y., uses an optical coating called LaserGold for the guidance beacon reflectors it's been shipping to Hughes Aircraft (now Raytheon) for the last 20 years.
The electrochemically deposited coating is said to provide ultrahigh-infrared reflectance that translates into extended missile range and accuracy. LaserGold's infrared reflectance is greater than 98%. And according to Epner President David Epner the company has been able to ship three-quarters of a million LaserGoldcoated parts with no defects. LaserGold is the NIST gold-reflectance standard for infrared.
In the TOW missile system, the beacon houses an infrared quartz-halogen lamp that illuminates in flight to show the missile location. Gunners look through the gun sight for potential targets, then fire their missile from a tube slightly larger then that used in bazookas. A pair of thin wires connected to the rear of the missiles spool out from the launch tubes.
These wires carry signals that control the missile fins. Gunners put their crosshairs on the target, sensors "see" the rearward facing beacon on the missile, and computers direct missiles to the target. The missiles can mount on jeeps or helicopters, but they are more often fitted onto armored personnel carriers such as the Bradley Fighting Vehicle.
Information for this article was provided by Epner Technology Inc., Brooklyn, N.Y., (718) 782-5948. www.lasergold.com