Abstract: A modular hyperspectral thermal camera that combines a wide field-of-view with a low erroneous recognition rate is described. The modular hyperspectral thermal camera provides such low erroneous recognition rates without any requirement for cryogenically cooling the associated optical components. The modular nature of the hyperspectral thermal camera permits easy exchange of the optical components and so provides a device that is easily calibrated and varied in resolution. In addition the modular nature allows the hyperspectral thermal camera to be readily converted to a broad band thermal camera, a full field spectrograph or a thermal bandpass filter camera, as required.

Abstract: A warning light (10) for external use on an aircraft comprises a high-intensity light output light source (14,20). The light source comprises a plurality of light emitting diodes (40) which are arranged to be pulsed with an overdriving signal (32) to produce a higher than normal intensity flashing light output. The overdriving signal (32) is generated by a pulsed drive circuit (30) in response to timing signals received from a flash pattern box at a rate of between 0.67 Hz to 1.67 Hz.