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Circuit Module

Technical Information

Catalogue No: C1293
Category: Unknown
Object Type: Module/Sub-Assembly/Component
Object Name: Circuit Module
Part No: 77820 10-503585-332
Serial No: ?
Manufacturer: Marconi Electronic Systems
Division: Airborne Display [ADD]
Year of Manufacture: circa 1994
Width (mm):
Height (mm):
Depth (mm):
Weight (g):
Location: Paul Fuller Entrance



This double-sided Circuit Module holds two CMC Micro-Cct, Hybrids, Dual Analog O/P, K0656-9421-00226 and one CMC Micro-Cct, H/B, Colour Video Selector K0656-SOCN-9421-00246. The Connector is a large Bendix type 77820 10-503585-332.
The function of the Module is not known but the Analogue Output suggests it has a display drive role and it may be from the Eurofighter HUD system.

The Typhoon HUD has a single element combiner using new computer generated holographic techniques to take out the distortion. The Combiner assembly features a single element comprising two glass plates bonded to produce a flat parallel sided assembly. A complex reflective holographic optical element (HOE) is recorded on photosensitised gelatine on the spherical interface sandwiched in the assembly which acts as the collimating Combiner. The construction optics to manufacture the HOE incorporate a CGH that generates a phase shape that could not be done using conventional lenses.

The combiner is also flat which minimises real world distortion and provides a total field of view (TFoV) of 30deg x 25deg with an instantaneous field of view (IFOV) of 30deg x 20deg.

This design is capable of cursive, raster and hybrid operation with a sunlight readable raster display. The minimal support structure gives a remarkably clear out-of-cockpit view optimal for air-to-air combat. The two seat variant has a similar HUD in the rear seat which can display video from the forward HUD camera. This design represents probably the `ultimate HUD' in service to date in a combat aircraft. The key feature is integrity such that the pilot no longer needs to monitor the HUD against other instruments thus reducing workload compared to Tornado for example.

In 1990 the Company was awarded a £54million contract in which the Airborne Display Division lead a consortium with Teldix GmbH of Germany, Selenia of Italy, and CESELSA of Spain,  to develop the EFA Pilot’s Head Up Display.

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