General
For an optimal projection, you need not only a good projector but also a suitable projection surface. The light emitted by the projector should be reflected as well as possible by a screen. But what does ‘well’ mean? The projection screen should reproduce the image information as closely as possible to how it is output by the projector, and ensure that your audience's view is not compromised. Only in this way will the image reach the viewer correctly.
To find the right screen, ask yourself the following four questions:
1. What type of screen should I choose?
2. What screen format is best suited to my projection requirements?
3. How high does the light output of my projector need to be to produce a bright and high-contrast image?
4. Which screen fabric is best suited to my projection requirements?
There are special features for each screen type that you should be aware of:
Installation screens
1. What should I look for when buying a roll-down screen?
2. What are the special features of a motorised screen?
3. What are the advantages of a ceiling-mounted screen?
4. What are the features of a framed screen?
Mobile screens
5. What should I look for when buying a tripod screen?
6. What are the features of a pull-down screen?
7. When should I choose a folding-frame screen?
8. What are the characteristics of a table screen?
Screen types
Installation screens
Installation screens are permanently installed in one location and cannot be transported. You can choose between different types of installation screens: motorised screens, roller screens and frame screens.
Mobile screens
Mobile screens are chosen when you want to use the projection screen in different places and need a lot of flexibility. There are different types of mobile screens as well. For example, a table screen is a very small, highly mobile solution for meetings and presentations on the go, while a mobile folding frame screen is particularly suitable for events.
Depending on the type of projection, a distinction is also made between rear projection (R) and front projection (F):
Front projection
The projector is located in front of the screen;
where the audience is also located.
Rear projection
The projector is located behind the screen; the audience sits in front of the screen.
Screen format
Depending on the type of application, the projected image has a certain format (height/width ratio). Presentations are usually displayed in 4:3 format, while films are often displayed in 16:9 format. For optimal projection results, it is therefore advisable to choose a screen in the format that best suits the purpose or the native format of your projector.
For the best projection experience, the audience should not sit too close to the screen, nor too far away from it.
The minimum distance between the viewer and the projection surface is 1.5 times the width of the screen. If the distance is smaller, the viewer is forced to move their head to perceive the whole image. The maximum distance between the viewer and the projection surface is six times the width of the screen. If the distance is greater, the viewer may no longer be able to read texts.
The optimal distance between the viewer and the projection surface is 4.5 times the width of the screen in a seminar or conference room and two to three times the width of the screen in a home cinema.
To be able to see the whole picture without moving your head, the angle between the viewer and the projection surface should not exceed 80° horizontally (40° to the right and left) and 50° vertically (20° up and 30° down).
The light
To determine the required light output of the projector, two light values are crucial:
day and ambient light, for example, is 150-180 lux; in a living room or office, it is 200-750 lux.
To ensure that the projected image is clearly visible, the ratio of ambient light at the screen location (measured in lux) to the light output of the projector must be 1:5. The stronger the ambient light, the greater the projector's light output must be to produce a bright and high-contrast image.
The screen surface
The reflection behaviour of projection surfaces can be classified into four groups (D, S, B and R) according to the international standard ISO 8396 and the German standard DIN 19045 Part 4 and is defined according to the luminance factors in relation to the viewing angle. The luminance factor measures the reflectivity of the screen surface to be evaluated compared to a white standard reference surface (barium sulphate) under standardised projection conditions and thus answers the question of how much brighter it is.
D Diffuse reflection, matt white screen
- Luminance factor: approx. 1.1
- Horizontal viewing angle: approx. 40°
- The projector beam is reflected evenly in all directions.
S Specular reflection (at the mirror angle)
- Mother-of-pearl coated screen surface
- Luminance factor: approx. 1.6
- Horizontal viewing angle: approx. 30°
- The projector beam is reflected in a preferred direction and is therefore compressed.
B Beaded reflection (back to the light source)
- Beaded surface
- Luminance factor: approx. 3
- Horizontal viewing angle: approx. 15°
- The projector beam is reflected back to the light source.
R Rear projection (transmitted light projection)
- Luminance factor: approx. 1-5
- Horizontal viewing angle: approx. 15°-40°
- The projector's light beam is directed through the screen and produces an image on the front of the screen.
Manual screen
The classic screen with manual operation.
A manual roller screen is the most affordable type of projection screen. This does not necessarily apply to the quality of the material or workmanship, but primarily to the built-in, manual roller mechanism. The screen is extended by hand and must be locked in the desired position.
Advantages
The advantage of a roller screen, in addition to the lower purchase price, is the fact that no cables or control systems need to be laid or attached – so a power supply is not necessary at the installation point. The screen can thus be easily attached and used at any point.
Disadvantages
One disadvantage is that a projection image that is neatly fitted into the black masking will only fit permanently if the screen is always extended to exactly the same position. Compared to an electric screen, the screen is somewhat less convenient to use.
Roller screens are available in different qualities and projection screens with a simple roller mechanism (here the screen must be extended and retracted by the user) or a soft-return mechanism (here the screen slowly retracts into the casing after a short pull on the handle). Due to their manual operation, roller screens are generally only offered up to a width of 300 cm; larger types are difficult to operate manually.
Conclusion
The perfect choice for all simple installations and budgets.
Motorised screen
The convenient classic.
Motorised screens, like manual screens, are among the classic screen types. Depending on the type, features and technical specifications, motorised screens are available in all price ranges, sizes and formats, from entry-level to absolute professional custom-made products. Ceiling-mounted solutions are also only available in the motorised screen sector.
Advantages
Compared to a roller screen, operation via buttons on the screen, but especially via remote control, is much more convenient and also more precise. If the Screen is mounted and adjusted in the correct position in relation to the projector, it will always descend to the set position in the same way – perfect installation and fitting of the projected image into the black masking is always guaranteed. In addition, the electrical operation is gentle on the mechanics and the fabric, as it is always wound and unwound with constant calm and little force.
Disadvantages
One disadvantage is that a power supply must be provided at the installation point and cables and control buttons must be laid and attached. This may not always be possible in all rooms (e.g. in old listed buildings, museums, churches, etc.) or may not be desired for visual reasons.
Motorised screens usually offer the widest range of options: with different fabrics, in large widths, with or without lateral tensioning, with different control options (IR, RF, media controls, etc.) and, above all, as a custom-made product (this is usually not offered for roller screens and makes little economic sense).
Conclusion
For a durable, functional and convenient installation, a motorised screen is the best choice.
Recessed ceiling screen
The almost invisible solution.
Recessed ceiling screens are motorised screens that are mounted in the ceiling.
Advantages
Because the screen is neatly and elegantly integrated into the ceiling, the design is flush with the ceiling. This makes it almost invisible in the room when not in use. In addition, durability is a top priority, because the mechanics and especially the projection screen are protected by convenient operation via a wall switch or remote control.
Disadvantages
A disadvantage of ceiling-mounted screens could be the somewhat more complex installation in the ceiling. For this purpose, the ceiling must be prepared for the installation of the ceiling cut-out and the power connection. Maintenance can also be carried out after installation via side flaps.
Conclusion
For a permanent installation, this is the most modern and appealing solution for hiding the screen when not in use.
Frame Screen
The special solution among classic screens.
A frame screen is a special projection screen that can still be classified as a classic screen. It ensures that the projection surface is always perfectly flat in all areas of the image.
Advantages
Since a projection screen fabric is a flexible fabric, changes in room climate (temperature and humidity) will always affect the flatness of the fabric – a framed screen is unaffected by this, as the tensioning of the fabric ensures that it remains perfectly flat in the long term.
Framed screens are available in different qualities and types: frames with a powder-coated surface or velvet covering (significantly better at preventing reflections of the projection image at the edges), as a classic frame flat on the wall or curved (here, the projector's light beam, as well as the eye, is always exactly the same distance from the screen surface in every area), with a large selection of screens and in all price ranges.
Disadvantages
A framed screen requires permanent space because it cannot be retracted when and is therefore always completely visible. It is permanently exposed to environmental conditions (sunlight, dust, smoke, etc.).
It is therefore usually only suitable for installations in home cinemas or rooms where the space of the screen and its permanent appearance do not interfere.
Conclusion
The right solution for quality demands.
Tripod screen
The classic among mobile solutions.
Tripod screens are very practical because they consist of one piece and have a good stand due to their tripod – especially on uneven surfaces.
Advantages
The advantage of tripod screens is that they are easy to set up without tools. The projection surface can be positioned very flexibly because both the lower tube and the upper weighting bar can be set at different heights. This makes this screen type suitable for all applications and very flexible to use.
Disadvantages
A disadvantage is that a tripod screen requires a wider base than many other mobile solutions. It also makes sense to purchase an optional soft case for transporting the screen, in order to transport and store the screen safely.
Conclusion
Due to the optimal price/performance ratio for all mobile projections with a size up to 2.40 m image width, this is the right choice.
Pull-up screen
The professional appearance with a high mobility factor
Pull-up screens are slightly more convenient to set up than other mobile solutions because the screen is simply placed on the floor and pulled up. Celexon offers solutions with both a telescopic pole and an integrated scissor hinge.
Advantages
The advantage of this is that the case protects all elements when closed. The Screen can be easily transported and set up and does not require a separate bag.
Disadvantages
A disadvantage may be the relatively fixed positioning of the projection area. This can only be adjusted upwards to different heights (e.g. in the case of scissor-joint systems). Similarly, pull-up screens require a flat surface to stand on.
Conclusion
Ultra-mobile and compact – the professional solution for those who are often on the road.
Folding frame screen
The mobile solution for the big picture
Folding frame screens are a very practical solution for mobile large-screen projections. Widths of over 4m are no problem. The screens are stretched with the fabric as with a classic frame screen and set up on feet.
Advantages
The entire screen is delivered in a very sturdy flight case and is therefore very suitable for the rental business, at trade fairs and events – wherever a large audience requires a large projection. Various heights can be set, a good flatness is always guaranteed and the construction is still simple and can be done without tools. Another advantage is the option to replace the projection surface. This means you don't have to buy two complete screens, but can switch between the front projection screen surface and the rear projection screen surface. This way, you get double the use at a significantly lower price.
Disadvantages
One disadvantage may be that the folding frame screen is best set up by two people and is very difficult to set up alone.
Conclusion
The optimal choice for events or functions with a picture width of approx. 2-4 metres.
Tabletop Screen
The ‘small’ one among the mobile screens
tabletop screens are the ideal addition to mini or pico projectors, as well as the new LED projectors. Widths of up to about 1m are possible. Unlike other mobile screen types, the tabletop screen is mounted on the side. The side parts, which serve as a tube, have fold-out feet that make assembly easier.
Advantages
The screens are very compact and can be set up easily and quickly with just one hand. The low weight and small size make them the ideal travel companion for business travellers who want to avoid presenting on a notebook screen that is too small, or a great entertainment factor in a child's room as an alternative to the usual TV screen.
Disadvantages
Due to its size, the table screen is not suitable for a large audience and is correspondingly limited in its field of application.
Conclusion
The perfect addition for projections up to 1 metre image width.
