Whenever there is a requirement for a large-scale display solution, it’s easy to think of the accessible combination of a projector and a matte white screen. This has been the traditional go-to business approach for many years.
Projectors can be cost effective and are solid and reliable, with variable optics to find the best ratio to map a large display screen. However, though flexible, they are no longer the only display solution worthy of consideration and may not always offer the ideal qualities to address operation requirements.
Direct view LED displays have become a standard for outdoor digital signage and are a top solution for marketing purposes due to their high performance regardless of present lighting conditions. The demand for reliability is what has made direct view LED tiles as welcome on the Vegas Strip as they are in command-and-control rooms.
Read on to discover why you should consider direct view LED displays compared to projection displays.
Direct view LED displays vs. projection
If price point is at the top of your criteria, opting for projection is often the right solution – but a closer look at the key attributes of direct view LED displays shows that they can deliver and excel compared to the traditional alternatives.
- Picture quality
Projectors may have previously been the best way to put images and video onto a large screen, but it has always faced the same challenge; environmental light can drastically affect picture quality. Many projector installations rely upon good lighting control measures to avoid artificial or natural light sources washing out the image, reducing its contrast and ultimately its impact.
Projectors rely on delivering their light paths to a screen surface that often requires finishes such as optical coatings, to ensure that the images are reflected to the viewer whilst retaining the best quality possible and producing minimal artefacts.
Direct view LED panels don’t have that problem. Instead of reflecting light, they emit it directly to the viewer from the LEDs. This allows the technology to operate in lighting conditions that would be unfavourable for projection, and ultimately means a higher image quality over time.
Direct view LED displays also allow for ‘true blacks’ as opposed to the slate colour shown by many displays when attempting to display black. Projectors struggle to compete with this capability, as they must compromise between high levels of brightness and contrast which are affected by the materials of the projection screen.
Additionally, as you increase the size of a display, projectors must use extra effects such as digital edge blending and overlapping to provide a continuous image effect. This sacrifices pixels on the display and is detrimental to the display as a whole. Direct view LED displays can be arranged edge-to-edge without the need for image overlap, preserving the overall quality of the display.
For some displays, the introduction of edge-blending also causes further artefacts such as the double intensity of light produced where the projected light paths are delivering duplicated pixels over the blend zone. Consequentially, dark content such as a night sky ends up unnaturally lightened.
Direct view displays have a high refresh rate, meaning they can update the content on screen incredibly quickly to create moving images with a flicker that is imperceptible to the human eye.
Like projected displays all of the High Dynamic Range (HDR) effects can be appreciated upon a direct view LED display.
Refresh rate is measured in hertz (Hz), and many direct view LED displays are able to refresh at a rate of thousands of times per second.
This makes direct view LED displays combined with simulation environments – joint ventures that are possible with partnerships like Barco and ST Engineering Antycip – even more immersive and scalable.
The refresh rates for both projection and direct view LED displays have increased over time. Direct view arrays are now capable of supporting simulator content that can require as much as 240 frames per second. Some projectors that utilise colour wheels can produce artefacts with fast moving content due to smearing effects. Direct view displays have no such problem thanks to a lack of moving components.
When used with virtual reality, some direct view LED displays can support Multiview 3D stereoscopic images which supports two simultaneously tracked dynamic views or multiple 2D content sources delivered to an audience on the same display, separated by their choice of active eyewear.
Projectors struggle in environments with high ambient light – think of the low lights needed to fully enjoy a cinema experience. Some screen surfaces can reject the unwanted light, but it is nevertheless common for environmental light sources to ultimately impact the feasibility of projected light paths. By contrast, since LEDs are their own sources of light, direct view displays don’t struggle in sunlit areas and remain perfectly visible.
Additionally, the gap between projector and screen presents a problem when choosing a suitable place to install them. Any object in the projector’s beam obliterates out a section of the image, and the projector itself can be moved or knocked out of focus.
Direct view LED displays don’t require as much space and this also makes them highly applicable to virtual reality use cases. A user can gesture and interact without fear of intersecting an overhead light path and there is no shadowing to the visual content.
A direct view display is made up of a series of tiles, granting a certain level of freedom in how the display itself can be constructed. Panels can be arranged in patterns or used to make constructions like cubes and pyramids. There are even walkable surfaces and curved modules that can help to address cylindrical screens.
This means that LED video walls can wrap around tricky architecture such as 90-degree corners, arches, and circling columns, and aren’t as constrained as projector screens, which must hang flat and be undisturbed by air currents.
Direct view LED tiles are also bezel-less to enable their ability to align their pixels together, meaning edge-to-edge display capability for a continuous uninterrupted image. Projector images are often overlapped and digitally corrected to afford such a continuation over a particular image size, which introduces a host of challenges previously mentioned.
Scaling a projector to cover more surface area means that the pixel size and density changes dramatically combined with the intensity of the brightness. Direct view approaches offer a consistent result across the dimensions with the only main compromise being that of cost and the fact of having a fixed, unalterable resolution.
Projectors have the aforementioned problem with needing a traffic-free gap between the projector itself and the screen. The larger the display, the wider this gap typically needs to be, opening the area in which interruptions can occur. The projector also needs to be connected to a video source, introducing another required point of connection, and calibrated once in place.
The projector chassis needs to be mounted precisely, then focused and configured to deliver its light path at the best possible angle to the screen surface, which can often lead to a time-consuming design process. It may also demand custom bracketry with compromises needed in some cases such as pitching the projector, which then needs digital correction approaches to be applied.
Direct view displays require their own time to set up, with multiple tiles needing precise alignment and support structures required to allow cabling and to support the tiles themselves. However, once installed, a direct view LED display does not need to be quite as guarded, and is less likely to suffer from physical intervention of its setup.
Direct view LED displays can offer fantastic cost savings over a long term use case. Their initial acquisition cost may be more expensive than a projection setup, but over the time there is typically less intervention necessary and if an engineer has to disturb the display to replace a damaged tile it is often less time consuming, as many systems have front accessibility and designs that aid the installer to automate the alignment process.
With projectors, an intervention that requires a projector swap can necessitate the need for more expensive access equipment and handling gear to lower a heavy projector from its mounting and to replace it, aligning the new unit back into the array. Despite the advantage of camera based auto-calibration technologies, projectors may also require colour matching and time spent to return a uniform image with the replacement.
The LEDs utilised in both projected and direct view displays can offer a life span of up to 100,000 operational hours, whereas laser projectors may only operate on full power for periods of up to 20,000 hours before they are half as bright as they originally began their life. As such, a calculation needs to be made to whether they are able to deliver the desired result for the life span of the desired usage.
ST Engineering Antycip provides cutting-edge simulation solutions for industries including engineering and construction, defence and cyber, and many more.
Our partnership with Barco lends us their expertise in visual display technology and creating incredible exhibits, displays, and events.
To learn more about our solutions and the partners we work with, contact us today.