Videowalls emerged in the 1980s and were initially used in entertainment and sales environments. These primary systems consisted of a set of CRT televisions that displayed a single consistent video image. During the 1990s, new imaging technologies were developed for CRT displays and videowall processors capable of handling multiple input and output signal formats were introduced, making them ideal for high-resolution graphics display and the growing demand for high definition video that emerged in that decade.
When it is needed to create a central point of information for equipment in a control room, especially in a large format that allows operators to view multiple streams of content clearly and simultaneously, videowalls become the predominant solution.
What is a videowall?
A vide wall is a display system made up of an array of projectors or monitors that work together as a single unit. Unlike a single display, a videowall offers a much larger image with higher pixel resolution by combining multiple displays to form a single image that allows for displaying wide images and presenting multiple data sources simultaneously. A videowall typically covers a considerable portion of a wall and can come in a variety of shapes, orientations, and sizes, from two screens to hundreds.
How are videowalls used?
Videowalls are primarily used to display multiple sources of visual information in an accessible manner in control rooms, such as network control centers, and command and control rooms. Additionally, they are used in digital signage to attract attention and create visual impact in public places such as company lobbies, train stations, points of sale and other similar environments.
In this article we will highlight the strengths and weaknesses of each technology focused on control rooms, critical environments 24/7, with the sole purpose of simplifying your choice. The objective of the text is to guide our clients towards the product that best fits their control room.
Although the popularity of videowalls continues to increase, the task of designing these unique display systems may be new to many AV integrators so understanding each element, as well as the physical aspects of the environments in which they are used, will help you. They will help avoid common pitfalls when designing your videowall.
There are three predominant technologies for creating videowalls in control rooms: tiled LCD, rear projection cubes (RPC), and direct-view LEDs.
How to determine which technology is best suited for your needs?
All organizations seek to maximize and take advantage of the investment they make, especially in critical environments in operational technology and visualization systems. For this reason, in this article we mention some of the fundamental differences between various technologies. Although there are other factors that also affect decision making, this publication can certainly provide guidance.
Therefore, it is always advisable to contact us or any of our partners before making a final decision.
Room and wall size are key factors to consider when choosing technology for the videowall in a control room. A summary of the recommendations:
• For small rooms with limited space, LCD technology is preferred due to its low profile and good visual quality even at close range. Additionally, LCD videowalls are ideal for interaction in smaller rooms.
• Rear projection cubes are better suited for larger spaces as they require more depth and work better when operators are located further from the wall.
• Direct view LED vide walls also work well in larger venues as they are slim and take up little space, but require an appropriate viewing distance depending on pixel size to achieve the best visual quality.
It is important to note that LCD video walls are not limited only to small installations and can also be used in larger rooms depending on your needs.
The lighting conditions in a control room are an essential aspect. In the past, control rooms were often dark places with little ambient light that could affect visibility on the videowall. However, today technology and control rooms have changed.
Brightness requirements in videowall applications may vary depending on the specific situation. In environments with high ambient light, such as rooms with walls of windows, higher brightness may be needed to improve overall contrast. However, in many control room applications too much brightness can be counterproductive, as people may experience headaches or eye strain if they work in front of the videowall for long shifts.
On the other hand, if the brightness is insufficient the contrast may be too low, making it difficult to quickly and accurately interpret the information. For typical control room applications a nominal brightness of 500 cd/m² is usually adequate and reasonable, however, in certain cases, brighter displays may be beneficial for control room applications.
The location and type of light source can have a significant impact on LCD, RPC and LED videowalls in terms of light reflections. There are two types of reflection: specular (like a mirror) and diffuse (like a diffuse reflector).
LCD videowalls tend to behave like specular reflectors, so it is important to place light sources strategically to avoid interference with operators’ viewing experience. On the other hand, direct view LED videowalls act as diffusers and work best in darker rooms where contrast is optimal. In summary, the choice of videowall technology must also take into account the management of light reflections in the specific location of use.
Soon we will continue giving you guidelines to choose the best videowall technology for your control center according to the work spaces, the information displayed or scalability.