System and method for stimulating night vision goggles

DETAILED DESCRIPTION The above-mentioned needs are met by the present invention, which is used to stimulate a pair of conventional night vision goggles in a conventional flight simulation environment through a large dynamic range of light intensities.
The display system for stimulating the night vision goggles of the present invention preferably includes image generation means for generating video signals that preferably comprise both conventional visible background video and high-fidelity NVG video signals.
The system further includes a background image projector that is responsive to the visible background video signals produced by the image generation means for projecting background images and an NVG image projector that projects NVG imagery responsive to the NVG video signals produced by the image generation means.
The NVG imagery is preferably capable of stimulating the night vision goggles and, to stimulate the night vision goggles across a wide dynamic light intensity range, includes both near infrared raster imagery and calligraphic imagery.
The preferred stimulation system incorporates image processing means for controlling the NVG image projector such that the NVG image projector displays the near infrared raster imagery and the calligraphic imagery in a time-multiplexed fashion.
That is, within a single display frame (e.
g.
, a 60 Hz frame), the NVG image projector displays the near infrared raster imagery for a portion of the frame and then displays the high-intensity calligraphic imagery for the remaining portion of the display frame.
According to one embodiment of the stimulation system, the system provides a passive means to reduce or limit the size of the entrance pupil of the night vision goggles while the raster imagery is displayed such that the imagery may be viewed with a full depth of focus.
The size of the entrance pupil is then increased while the high intensity calligraphic imagery is displayed.
Preferably, the size of the entrance pupil is controlled in sync with the time-multiplexed display of the raster and calligraphic imagery