Ultra Short Throw or UST Projector Screens require much more consideration than standard matte screens. Ultra short throw screens need to have:
- Ambient Light Rejection (ALR) and specifically Ceiling Light Rejection (CLR)
- Low Screen Gain,
- High Viewing Angle
- Appropriate Screen Size for the room
In this article, we go into the details of specifications related to screens for Ultra Short Throw Projectors.
What is an Ultra Short Throw Projector?
Standard or Long throw projectors are placed a substantial distance from the screen on which the image is projected. These projectors require a distance of at least 8 feet to produce a large image.
Short throw projectors provide the advantage that they can be placed closer to the screen down to 3 feet to produce the same size of image, requiring less room to perform their function.
A further category of projectors carrying more advanced lenses is the Ultra Short Throw (UST) projector. They can be placed almost right in front of the screen – only a few inches away to produce considerably large-sized images. UST projectors throw the image in an upward direction and the ability to sit in such close proximity to the screen gives them the advantage that they can be placed in smaller rooms.
But the compactness of the UST projection setup means much more than just space advantage. The feature makes them an excellent replacement for TVs. Considering they can cater to screen sizes larger than 100 inches and allow the possibility of achieving variable image sizes, they are serious contenders for the living room TV space.
How well do UST projectors perform?
Besides image size, UST projectors do not lag behind in image quality. They are some of the best in terms of performance.
As far as resolution goes, they offer great resolution even up to the 4K level.
They function well in normal ambient lights because the image brightness is less affected by external light due to the close positioning of the projector. This together with an Ambient Light Rejection (ALR) screen makes projection quality top-notch, once again, making UST projectors some of the likeliest TV replacements on the market.
What lets UST projectors down is mainly the price factor. The tech comes at a hefty cost and requires a special screen to complete the setup. The redeeming factors are that compared to long throw projectors, cable costs are lower because of the lower lengths required and the absence of the cost of installing long lengths of cable. Also fixed mounting costs such as ceiling or wall mounting are avoided since the projector is just placed at the screen itself.
What is an ultra short throw projector screen?
We’ve discussed the quality of the UST projector above, but the picture is not complete (forgive the pun). A projector may have all the great specifications we want but it’s only as good as what the screen can provide. The picture quality game is a combo performance by the projector and screen duo.
Are projector screens necessary? With long throw projectors, you might project on a clear wall and only get some image deterioration. But ultra short throw projectors cannot work well at all with walls. Any imperfection or bump in the wall is magnified because of the projection angle. It’s like a setting sun casting long shadows. You will instead need a suitable ultra short throw projection screen.
What is an ultra short throw projector screen? While standard projectors can use standard screens, the video quality with UST projectors can only reach its peak with a type of screen called Ambient Light Rejection (ALR) Screens.
Standard matte white screens reflect not only the projected image to the viewer but also any overhead light or ceiling light. The result is that these screens will produce a washed-out image compared to the sharper images on an ALR screen. The ALR screen achieves this through an optical surface technology and special screen materials that direct any ceiling light that falls on the screen away from the viewer but reflects light from the projector light toward him.
Because ceiling light reduction is crucial for UST projector screens, Ceiling Light Rejecting (CLR) screens are a type of ALR screen for UST projectors and are the preferred type of screen.
What this does to the image quality is make it more vibrant. The excellent color saturation is miles ahead of any standard screen. Even in the presence of ambient light, the black levels will be deeper and darker so the contrast ratio is improved.
What ALR screen specifications to look out for
When looking for an ALR screen for UST projectors, the most important specifications to consider are
- the screen gain,
- the viewing angle
- the screen size.
The gain is a measure of how much light the screen reflects. The higher the gain, the brighter the image will be.
A gain value of 1.0 implies the screen reflects light at the same brightness at which it falls upon the screen. A gain higher than 1.0 means the reflected light is brighter than the original light. A gain lower than 1.0 implies light is absorbed by the screen material and the reflected light is less bright than the original light.
For standard projector screens, the gain is typically between 1.0 and 2.0. But not so for ultra short throw projectors. These already provide enough brightness because they sit so close to the screen. In their case, we aim to reduce the brightness of lights from sources other than the projector. For UST screens, we target a lower screen gain of less than one. Therefore, you will find ultra short throw screens with gains from 0.4 to 0.6 for your UST projector.
The viewing angle is the angle at which the screen can be viewed without losing any brightness. In other words, if you are outside the viewing angle, the gain reduces significantly. The viewing angle is typically between 160 and 180 degrees which provides for wide viewing.
The size of the screen should be large enough to fit your projector, and should also be suitable for the room in which it will be used. The big screen experience counts.
Ultra short throw ALR screens are typically available in sizes of 80 inches to 120 inches. They can even go up to 150 inches but this is less advisable as the image spread is so large that the brightness is less than ideal.
A point to note is that the screen size refers to the length of the diagonal across the screen. Therefore, a 120 UST ALR screen will be sized with a 120 inch length diagonally from one corner of the screen to the opposite corner. Also, screens are normally available with a 16:9 aspect ratio.
Installation Considerations for your UST Screen
Fixed frame screens are installed on the wall. Ceiling-hung screens are also available. They provide an advantage of a longer lifespan since the sensitive ALR screen material does not get damaged during frequent roll-in or roll-out of a retractable system.
Drop-down screens and Floor-rising screens are retractable and offer a very clean set-up. With electrical or motorized screens, convenience and an additional wow-factor is obtained for some.
With the larger screen sizes, consideration also needs to be given to the height of the screen installation. The upward viewing angle with high screens will make it uncomfortable to watch videos over extended periods of time. A rule of thumb is to have the lower third of the screen at the viewing height which is normally between 3 to 4 feet.
Conclusion
We’ve gone through in detail with the specifications you need to consider for UST ALR screens. These are different from specs for screens with other projectors. Armed with this knowledge, you are now all set up to make the right purchase for a super viewing experience.