The rear projection is not the conventional way for projecting, for everyone, but it does have its benefits, and in some cases, it is the best method to use.
To make a rear projection, you need a rear projection screen. This type of screen is different from the regular projector screens. It is a special screen that diffuses projected light; and the good news is, it works with almost all projectors.
At the end of this article, you will know what a rear projection screen is, how it works, and the best material for this screen. So, let’s get to it.
What is a rear projection screen?
A rear projection screen transmits light from the projector directly to the viewer. This type of projection screen does not readily reflect light, but rather allows the light to pass through it and get to the viewer.
When using a rear projection screen, the projector is positioned behind the screen, and not in front of the screen. Rear projector screens have better viewing angles, brightness, and contrast. The reason is, the screen can control the light path shooting towards the viewer and reflects only a little to the projector.
Most of the light coming from the projector gets to the viewer and there is no distortion of the image quality. The projector is also closer to the screen; this contributes to the increased brightness.
How does a rear projection screen work?
A rear projection screen transmits light from the projector, through its surface, and directly to the viewer. It diffuses the light hitting its surface rather than reflecting it; although some light is reflected to the projector and is consequently ‘lost’.
When the image is viewed from the position of the projector, it appears dim. But when viewed from the other side, the image is brighter, and the screen has a higher gain. However, the gain changes depending on the viewing angle; an increase in the viewing angle will cause the gain to fall.
In rear projection, most of the devices are positioned behind the screen, but you can have your speaker in front of the screen if you want to. This positioning limits the use of rear projection screens to large rooms or areas with enough space.
The space needed will depend on the size of the projection screen, the projector type – either a long-throw or short-throw projector, and the lens of the projector.
Rear projector screens have a higher gain. However, to enhance the image you need to reduce the ambient light coming from behind the screen.
What is the best material for the rear projection screen?
It is preferable to make a rear projection screen with a semi-translucent fabric that is grey. This could be any material that can efficiently diffuse the light coming from the projector. Some materials will serve well for this purpose. They are:
Spandex is a fiber material made from a synthetic polymer. It has a high level of elasticity and can be used for making projection screens.
If you will be using spandex as your rear projection screen material, then be sure to get one with the highest cotton mix possible.
Trapeze by Dazian
This is another material that you can use. It has good fabric tension, and it is durable. Dazian’s Trapeze is available in widths from 120″ to 130″; it depends on the type that you want to use. It comes in different colors; there are also Dove Gray and Titanium colors.
You may find rear projection screens expensive; considering their effect on the image quality it won’t be a surprise if they cost much.
However, that does not mean that it’s the end of the road, you can use the DIY method to make a rear projection screen for yourself. Let’s see how you can do this.
How to DIY a rear projector screen?
What do you need?
- A rear projector screen material: you can choose any of the types mentioned above.
- A pipe: the rear projection screen material will be attached to the pipe. You can also use wood instead of the pipe.
- Pipe connectors: if you will be using wood then you need a metal “L” bracket and screws instead.
Besides, you may need to prepare:
Measure out the length of the pipe that you intend to use, and cut off the excess with the handsaw. There should be four pipes; two for the longer sides and two for the shorter sides. After cutting the pipes, you can fix the pipe connectors at the edges; this forms a frame for your projection screen.
Spread the rear projection material on the floor, and place the frame on it. Use the knife to cut out the materials at each side of the screen. You can leave out some extra to fold around the pipes.
Cut out small sizes of tape, and with each, glue the rear projection material to the pipe. Do this for all sides of the frame making sure it is properly secured. Once you’re done securing the sides, the screen is ready for use.
Mount it at a good distance away from the wall, and set up your projector and other needed devices, behind it. Turn your projector, and view the image from the other side.
You do not need a special projector for a rear projector screen, since almost all projectors can flip images. Using the rear projection feature, the image can be adjusted so you will be able to view it properly on the other size.
One benefit of the rear projection screen is that it prevents shadowing. It allows you to stand in front of the image without blocking the light from the projector.
This makes it great for making presentations, as you can move freely without casting shadows. It is also great for motion sensor games.
In rear projection, it is important to have enough space behind the screen especially if you are using a long-throw projector.