What exactly is a rugged display? How do you ruggedize your products? How are your displays different than a consumer display? These are questions that often arise when we are talking to potential customers so we thought that we would take the time to address them in this article. There are several key design features that distinguish a rugged display from a similar consumer monitor. Make sure you consider these before purchasing a rugged monitor:
Most consumer displays are enclosed in plastic. Plastic is typically not a suitable material for use in a rugged product because it cracks under heavy vibration or shock and has a relatively low melting point compared to metal. It’s also more challenging to minimize electo-magnetic interference (EMI) when using a plastic enclosure. As a result, most rugged monitors are housed in a lightweight aluminum enclosure.
Corrosion & Scratch Resistance:
Most rugged products are housed in a metal enclosure so it’s important to coat or seal the metal with a finish that it is scratch and corrosion resistant. This is typically done with power coating or anodizing. All of ViewPoint's displays are anodized. Anodizing is an electrolytic passivization process that is used to increase the natural oxide layer on the surface of a metal part. Anodizing thickness increases the wear resistance, corrosion resistance and electrical / thermal insulation of the part.
Industrial Components and Conformal Coating:
A circuit board won’t survive an in extreme environment unless it’s designed with components that can handle the wide operating temperature that the product may be exposed to. Additionally, certain components and connectors may need to be attached to the board using through-hole components instead of surface mount so that they don’t detach from the board in high vibration or shock conditions. All of the components on the circuit boards should be covered with a layer of transparent conformal coating to protect the components against moisture, dust, and external chemicals.
Optically Bonded Glass with Anti-Reflective Coating:
Most consumer displays are not viewable in direct sunlight since they aren’t normally used outdooors. Rugged displays are typically used in outdoor environments so they must be designed to be sunlight readable. This is done by attaching a piece of glass to the front of the display that has been covered with a special coating to minimize reflection. Such coatings will typically reduce the glare and reflection on the glass by 95%. This glass also protects the LCD from the elements and increases the contrast of the display.
Many traditional displays (both consumer and rugged) where designed with fluorescent backlights. These backlights work well but are made of very small glass tubes that can break in high vibration or shock conditions. LED backlights, however, will not break since they are built using silicon and don’t use glass. Some rugged display providers are still using fluorescent backlights but most have migrated to LEDs.