Performance Tests of True-Color Night Vision Cameras

This paper presents performance test results of true-color night vision cameras. Such cameras are sensitive to the visible to near-infrared (VNIR) portion of the spectrum allowing for the “true-color” of scenes and objects to be displayed and recorded under low-light-level conditions. True-color refers to an approximate reproduction of the subjective colors that would be seen by the human eye in daylight conditions. Monochrome green or grayscale imagery from image-intensified I2CCD cameras has been the standard for years; however, as the technology progresses the added benefits that a true-color system enables (such as increased information content and better situational awareness) are beginning to outweigh the drawbacks. Two different prototype cameras, employing two different true-color night vision technological approaches, have been recently developed and tested. One camera uses a fast-switching liquid crystal filter in front of a custom Gen-III image intensified CMOS camera. The second camera is based around an EMCCD sensor with a mosaic filter applied directly to the detector. In addition to visible light, both cameras can utilize NIR to (1) increase the signal and (2) enable the viewing of laser aiming devices. The performance of these two cameras are reported and compared to a monochrome night vision camera in terms of resolution, image contrast, color reproduction fidelity, SNR, range, and other parameters. Figures of merit designed specifically for the objective assessment of such cameras are used in this analysis. Approved for public release; distribution is unlimited