2 New NVIS Green A Intruder Filter Options

We’re excited to announce the development of two new glass formulations that meet aerospace industry specifications for night vision imaging systems (NVIS).

KO521 – Green A Intruder LED-compatible Glass Filter: Low Weight, High Transmission

The new K0521 NVIS filter maintains a similar chromaticity to its incandescent filter counterpart when using specific white LEDs. Resulting filtered light chromaticity meets the MIL-STD-3009, MIL-L-85762A, and RTCA/DO-275 requirements with corresponding night vision radiance (NRA) levels well below present standard expectations. These new filters can be used in civilian or military aircraft and function suitably as annunciator, indicator, and cockpit display light filter applications.


NVIS Green A Intruder Filter Glass
K0521-0.5 mm filter thickness is represented by green symbols and is illustrated for an assortment of different LED designs over a CCT range of 4000-5500K.


The NVIS application requires that cockpit lighting radiation be minimized and our new filters continue to exceed military standards with a low radiance output. Chromaticity values meet the military and civilian standard requirements when using specified white LEDs with a correlated color temperature (CCT) range of approx. 4000-5500K.

Demands for lower weight, LED-compatible NVIS filter options were answered with the newest designs by decreasing the historical LED-compatible filter product wall thicknesses to 0.5 mm. We are currently offering the K0521 filter at a 0.5 mm application thickness, along with a comparable color option for K0525 at 2.0 mm application thickness.

K0513 – Green A Intruder Incandescent NVIS Filter: High Color Saturation and Low Radiance

We continue to diversify our NVIS filter solution offerings by designing an increased color saturation Green A Intruder filter formulation. The K0513 formulation has been designed for use with an incandescent light source with a CCT in the range of 1600-2200K. The new filter design has been prepared to function at an application thickness of 1.0 mm. Although the color saturation has increased as compared to the traditional K050X filter systems, transmission remains in excess of 10% and provides decreased radiance for critical applications.


NVIS Green A Intruder Filter Glass
K0513-1.0 mm filter thickness is represented by olive symbols and chromaticity is illustrated over an incandescent CCT range of 1600-2200K.


The increased colorant hue and reduced transmission versus past NVIS Green A Intruder filters makes the K0513 filter a suitable candidate for use in applications where high contrast and daylight readability are critical design considerations. These new designs demonstrate our ability to customize these critical NVIS formulations to meet an array of design requirements, without sacrificing quality or functionality.

Contact our Solutions Consulting team to learn more about this new product offering and to request a quotation. Top

About the Author
Adam Willsey

Adam Willsey Adam joined Kopp Glass in 2009 after graduating from the NYS College of Ceramics at Alfred University with a BS in Biomedical Materials Engineering. In 2013, he completed his MS in Materials Science from Alfred University. As the Enabling Technologies Project Manager, Adam works closely with our engineers and production team to develop new glass compositions that meet our customer's color and transmittance requirements, while ensuring efficiency.