Creating the perfectly flat viewing surface

architecture - engineering - construction

Creating the perfectly flat viewing surface

July 11, 2017

Who knew a series of small tabs could be so important to having a beautiful picture, and a durable product?

One of the most important elements of creating the ultimate projected image is having the flattest viewing surface possible. Great contrast, brightness, and vivid and correct colors are important, but without a perfectly flat surface those attributes of a great picture don’t matter.

Fixed frame projection screens are one way to ensure the flattest viewing surface possible. Not everyone wants a huge screen hanging on the wall all the time, though, so they need a motorized screen. With motorized screens, however, the problem is how to keep the surface taut from the sides.

That’s where Draper’s innovative tab tensioning system is so important. A tab tensioning system uses a very thin cord running down each side of the screen through tabs, attached to the roller at the top and the dowel at the bottom. The cords are tightened, creating a flat viewing surface.

Most other manufacturers use adhesive to attach these tabs. This can lead to problems when the constant tension proves too much for the adhesive to handle, and it give way, creating “popped” tabs.

With Draper, you never have to worry about “popped” tabs. Here’s why.

All of our tab tensioned screen surfaces—including the tabs—are cut on Computer Numerical Control (CNC) cutting tables, which means every cut is made with digital precision. CNC represents the highest level of precision available in the manufacturing process.

The tabs are then folded to the backside of the screen and Radio Frequency (RF) welded. In this RF heat sealing (AKA dielectric sealing) process, the tabs are folded back and placed between two dies (electrodes). The RF produces heat by exciting the molecules to the point that they melt and create the bond. We use the same technology to create seamed projection screens. The strength of the seal is determined by three factors-

Sealing current (radio frequency power)
Sealing time
Pressure

The result is a much stronger tab, with no possibility of separation, as the tab and surface are fused into a single layer of material. In-house laboratory testing of our tabs shows that this RF seal is in most cases stronger than the material itself.

Our tab tensioning system is also nicer looking. Making a tab tensioned surface in this manner eliminates the puckering that can characterized the edges of tab tensioned screens made using adhesives.

When we introduced this new system several years ago, it represented a unique and significant improvement in tab tensioned screen design. It still does. We were so confident of our system that we decided to warrant all Draper tab tensioned screens against tab separation for five years from date of manufacture. We still do.

Click here to find the perfect tab tensioned projection solution for your next project. Whatever model you choose, the perfectly flat surface will create the perfect image you want, and for a long time to come.

Company: Draper, Inc.