|Category:||Head-Up Display [HUD]|
|Object Name:||Tornado HUD Dual Combiner Assembly|
|Year of Manufacture:||circa 1998|
|Location:||Archive Object Store|
Part No E3887/53718 Iss AA
Ser No 209
This is a complete dual combiner assembly from the Tornado Mid-life update HUD made by GEC Ferranti. These glasses use another technique of a special multi-layer coating called rugate technology. Rugates act like a single inhomogeneous film with a refractive index that varies continuously and periodically throughout the thin-film structure. The same impressive increase in transmission and reflection can be achieved as the ‘holographic’ system but without the bulk of the glass sandwich. Omitec originally developed thin-film rugate technology to manufacture "notch" filters of specific bandwidth. In 1991 flight tests of Head Up Displays, fitted with what was claimed to be the world's first airborne thin-film colour-selective graded combiners were commenced in a Harrier GR.7 and a Tornado GR.4 later in the year. Omitec also delivered Rugate coated Combiners to GEC Ferranti for the wide-angle HUD for the Royal Air Force's Tornado GR.4 mid-life upgrade.