| Ordering Nightshield filters |
| Order forms and inspection criteria |
| Products and specifications |
| Light-source characteristics |
| Incandescent light |
| LED light |
| Fluorescent light |
| Using Nightshield plastic filters |
| Filtering switches and indicators |
| Filtering LEDs |
| Filtering displays |
| Filtering laptops |
| Filtering handheld devices |
| Technical publications |
| About night vision |
| Introduction to NVIS |
| NVIS for aviation |
| NVIS for ground applications (secure lighting) |
| Measuring and certifying NVIS compatibility |
| NVIS worldwide |
| NVIS glossary |
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Notice
Nightshield® is a proprietary plastic NIR [near infrared] rejection filter manufactured by Korry Electronics. When placed over displays, it removes the NIR component of the display emission but maintains sunlight readability. Nightshield filters are used in many civilian and military applications, including crewstation displays for aircraft and ground vehicles, portable display systems, wildlife surveillance, forest fire surveillance and suppression, search and rescue flashlights, and ophthalmic lenses. Korry sells Nightshield in standard shapes, dimensions, thicknesses, colors, and filter properties. |
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Welcome to Korry’s information center for night vision imaging systems (NVIS) and Nightshield plastic filters
Ordering standard Nightshield filters and filter material
To order Nightshield products with standard parameters, and for more information on thicknesses, tolerances, as well as cutting and milling guidelines, please go to our order page.
A cost-effective solution for night-vision-compatible illumination
Nightshield filters are ideal for many commercial and military applications, including PDAs, laptops, palmtops, and other portable devices. Nightshield plastic NVIS filters are the ideal method for making virtually any light source compatible with NVIS, NVG, NVD, or any other night-vision apparatus.
For a summary of main filter types and specifications, go to our products and specifications page.
For discussion of how Nightshield filters can be used in various common applications and for technical papers, consult the menu under Using Nightshield plastic filters.
For general information about night-vision technology and lighting issues, consult the menu under About night vision.
Nightshield plastic NVIS filters are ideal for nighttime appications in commercial aviation, medical evacuation, search and rescue, law enforcement, and defense.
Nightshield filters are used in many civilian and military applications, including crewstation displays for aircraft and ground vehicles, as well as portable display systems in PDAs, palmtops, laptops, etc.
Nightshield filters are extremely durable. Where all-glass filters might fracture, Korry’s tough, lightweight plastic material survives the most demanding real-world environments.
Nightshield products perform dependably in many high-reliability applications, including Boeing 747, 757, and 767 aircraft as well as a range of military platforms: F/A-18, F-16, F-14, 737, A-10, A-6, EA-6B, B-1B, C-17, AH-1, AH-64, CH-47, SH-60, and the M1A2 tank.
The same optical performance is available in standard 1-mm and 2.5-mm thickness. Korry makes Nightshield in virtually any shape because plastic materials are easily processed by conventional machining methods. For example, a polygon-shaped filter with through holes and grommet inserts flies in the F-16 cockpit (yellow filter shown below).
Nightshield plastic NVIS filters are available in standard thicknesses, shapes, and colors, as well as custom configurations.
Light-source emission characteristics and Nightshield filters
The selection of an appropriate Nightshield night-vision filter strongly depends upon the type of light source. The following pages review the emission characteristics of incandescent, LED, and fluorescent sources and suggest appropriate night-vision filters for each one:
 Incandescent light sources
LED light sources
Fluorescent light sources
Incandescent, LED, and fluorescent light sources have widely different spectral emission characteristics. Incandescent (black-body) sources have broad-band properties, with emission throughout the visible spectrum and a majority of emission in the infrared region. In contrast, monochrome LEDs and tri-band fluorescent sources have narrow spectral output, with sharp, distinct features. Therefore, each type of light source requires a specific night-vision filter tailored to its spectral emission properties. Korry’s Nightshield filter materials address all LED and fluorescent variants. In the case of incandescent lamps, Nightshield filters are suitable for lower wattage lamps.
Nightshield filters in action: multicolor filtration on Sea King helicopters
A Southeast Asian air force recently used Korry Nightshield filters to modify a pilot steering indicator (PSI) on Sea King helicopters. Initially, a red plastic filter was replaced with a piece of NVIS Green Nightshield material cut exactly the same as the original and leaving cutouts for the PSI’s red warning indicators. The indicators were left purposely unfiltered to attract the pilots’ attention, especially when wearing night vision goggles. After initial flight tests, however, the pilots decided they wanted the PSI warning indicators to be filtered also. The solution was to add another piece of NVIS Yellow Nightshield to the NVIS Green Nightshield layer, covering the originally open cutouts. |
