NVIS (Night Vision Imaging Systems) Measurement of Displays in Aircraft

Military aircraft cockpits are full of a vast array of light emitting devices and display panels. Proper and balanced light emission of all devices is vital to the pilot, so they may read the information from the devices. When flying at night, a pilot will wear NVIS (Night Vision Imaging Systems) goggles. NVIS refers to the radiation emitted by the gauges, displays, and buttons. It is important that the goggles can see proper light emission so that the pilot can make immediate and correct actions to ensure a safe flight. NVIS googles amplify NIR radiation, 620 to 930nm, which is too weak for human eye to see, at least 5,500 times and indirectly convert it into visible light via a green phosphor plate.

MIL-STD-3009 (and MIL-L-85762) outlines NVIS’ spectral response, which means sensitivity of NVIS devices (such as NVIS goggles) for incoming light. It defines three categories of NVIS according to their spectral response performance, NVIS-A, NVIS-B and NVIS-C (NVIS-C will not be covered in this discussion).

MIL-STD-3009 describes chromaticity and radiance requirements for light emitting devices. It describes requirements by each color of light source, (NVIS Green A, B, NVIS YELLOW, NVIS WHITE) and by different light emitting devices.

NVIS-A still has sensitivity in broad visible range especially in red. NVIS-B has improved NVIS spectral response by reducing sensitivity in visible range. Ideally, NVIS has high sensitivity in infrared range while minimizing it in visible range.

It is important to note that light emitting devices need to satisfy those requirements of chromaticity and radiance, while minimizing emission of energy at wavelength of NVIS’s spectral response, which is typically 620 to 930nm.

For manufactures and designers of light emitting devices such as cockpit display panels, it is critical to be able to reduce energy in IR (infrared) range of wavelength, which becomes noise when viewed through NVIS.

In order to design and manufacture high quality light emitting devices, a spectroradiometer, which covers wide wavelength (visible and infrared) and detects small noise with high accuracy is required and needs to meet the requirement of measuring spectral radiation from 380 to 930nm.

Thirty-five plus years ago, NVIS technology exclusively used photomultiplier tube scanning spectrometers. A single measurement took minutes and instruments were bulky and fragile.

The Instrument Systems DTS-140D NVIS testing spectroradiometer system can ensure that aircraft displays/dial/buttons/indicators produce the correct amount of light and color, when viewed with a pilot’s quassi-night adjusted eyes. For example, the visible light settings might be optimized for 0.5fL or about 1.7 Cd/m2. The NVIS instrument simultaneous measures the amount of NIR light present in aircraft displays/dial/buttons/indicators to ensure that the night vision googles’ are not “blinded” or saturated.

Instrument Systems is the leader in CCD based spectroradiometers manufacturing 10s of thousand for the highly demanding white led color sorting. Introducing NVIS filters and a spectral stitching technique, the instrument can accurately measure both the visible light and ensure that the NIR light compliant.

Instrument System is qualified to test instruments per the MIL standards.

Part of the Konica Minolta group Instrument System is a reliable vendor that will be here to meet your future needs.

Color & Appearance Measurement Blogs

Light & Display Measurement Blogs

Privacy Preference Center