Spectrally enhanced vision system for low visibility operations

An enhanced vision system for providing an enhanced image displayed on a display unit of an aircraft, the enhanced vision system comprising:

• a sensor and a processor in communication with the sensor, wherein the processor receives data representing a visible light view of the scene and data representing a first and second filtered view of the scene, wherein the filtered view is provided using at least two narrowband spectral filters configured to detect a particular set of wavelengths of low thermal light that represents lighting objects with a specific color in a colored navigation system, wherein a first filter is focused on a first narrowband frequency and wherein a second filter is focused on a second narrowband frequency which does not substantially overlap with the first narrowband frequency, wherein, for each filter, the data representing the visible light view of the scene is subtracted from the data representing the respective filtered view of the scene, wherein the subtraction comprises first (a) multiplying the visible light view of the scene by a first scaled luminance factor associated with the first filter, and (b) multiplying the visible light view of the scene by a second scaled luminance factor associated with the second filter, and wherein the subtraction further comprises setting the first and second scaled luminance factors to different values such that the subtraction takes into account a first amount of background scene content associated with the first filter relative to a second amount of background scene content associated with the second filter;
• wherein the results of the subtraction involving the first filter and the subtraction involving the second filter are combined to create an image with a high contrast relative to the background scene and that highlights two different colors.