Environmental Standards: Is Your Military Display Tough Enough?A high-quality military display is tough enough to withstand virtually anything the environment can throw at it. After all, it is intended for use in military applications, which typically involve extreme conditions. Unfortunately, not all displays are up to par in this regard.
Before investing in a new display, military personnel should familiarize themselves with features that make them durable under a variety of extreme conditions. Understanding the characteristics that make displays rugged, durable and battlefield ready is critical to finding a reliable and long-lasting product.
What to Look for when Choosing a Military Display that can Withstand Extreme Environments
Military operations take place all over the world, in a variety of climates. The best military displays are designed to operate in temperatures as low as -40 degrees Celsius/Fahrenheit and as high as 71 degrees Celsius/158 degrees Fahrenheit and tolerate even greater storage temperatures. They should also remain operational when exposed to the effects of solar gain and temperature shock as defined in MIL-STD-810.
With specific regard to LCDs, extreme cold temperatures can cause latent video transmission which can drastically affect a crew’s responsiveness to an event. With advancements in lighting and circuit technology, experienced manufacturers today can overcome limitations commonly seen in the past.
Moisture and Debris
Moisture is an ever-present element which presents a host of challenges for electronics. Whether it is driving rain, high humidity, condensation caused from pressure differentials, or the innate nature in which the unit is installed, displays must be designed to eliminate the possibility of water ingress. A unit designed to meet the IP67 standard, submersion in 1 meter of water for 30 minutes, is more than adequate to protect against typical in-field installations. Typically encased in strong, corrosion-proof anodized aluminum, IP67-rated displays are also highly resistant to ingress of dust.
As with all electronic devices, displays generate considerable heat while operational. The temperature difference created between the ambient environment and the internal enclosure will undoubtedly cause condensation if not properly managed. Through the use of advanced gas transferring components, manufacturers today are able to equalize internal pressures and eliminate water vapor.
Display systems are comprised of many small components that are responsible for delivering video and communications without disturbances. Ballistic, gunfire, crash and transport shock levels commonly seen in the field, and as called out in MIL-STD 810, can expose these components to up to 40g of impact. Mechanical design and component selection are critical factors to ensure video transmission is uninterrupted.
Today's most resilient displays are designed to withstand constant vibrations of up to 5.2 G at frequencies between 5 and 500 Hz. The typical profiles defined in MIL-STD-810 require testing multiple cycles on three axes. By confirming this, personnel can ensure the display they use will continue to function optimally regardless of steady vibrations to which it is exposed.
Power Input Fluctuations
It is crucial to look for a rugged military display with built-in protection against a variety of power input fluctuation scenarios such as load dumps, reverse polarity, over voltage, under voltage and short circuit. Vehicle platforms in today’s defense industry present a wide range of variables, and selecting electronics compliant with MIL-STD-1275 can ensure the power fluctuations won’t negatively impact the device and mission.
Electromagnetic Interference (EMI)
One factor often overlooked in the search for a military display is electromagnetic radiation, or lack thereof. Invisible to the naked eye, this radiation can wreak havoc on the entire vehicle system. To counteract the effect of this radiation, a well-designed display will include an EMI shield.
Displays in particular must control the amount of interference emitted through the front glass window, bezel keys, and connectors. In addition, they must have protection from outside devices which may project their own level of interference. Guidelines and test procedures can be found within MIL-STD 461.
A military display is one piece of equipment that simply can't fail while out in the field. With that in mind, it is crucial to choose a manufacturer who not only designs their products to survive the most extreme environments and conditions, but also has validation experience.