Membrane Keyboards

Ultra-Switch® is a registered trademark of our program of our Membrane Keyboard program. All our keyboards are designed according to customer specifications.

General information on membrane keyboards

Our Ultra-Switch® membrane keyboards are manufactured in several different variants.

We can supply membrane keyboards with embossed contours, lowered keys, or embossed keys with polyester or metal domes.

All our keyboards are designed in cooperation with our customers to meet their needs and specifications. That's why we would always like to hear more about your ideas.

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Embossing

Our Ultra-Switch® membrane keyboards are manufactured in several different variants.

We can supply membrane keyboards with embossed contours, lowered keys, or embossed keys with polyester or metal domes.

Before the final choice of dome type there are several factors that should be considered:

A polyester dome is a heat-treated "bubble" in the top contact layer. Due to the fact that we have continuously improved our embossing processes for over 30 years, our polyester domes today are very uniform and work optimally in the temperature range between -30° C and +75° C. This particular type of key can be used with most constructions. Since all keys are embossed in one and the same process, the number of keys has no impact on the price per keyboard.

Polyester domes can only be used with embossed keys and has higher contact speeds (up to 50 milliseconds) than flat keys or metal-dome keys.

Keys with metal domes are probably the most widely used method for domes in a membrane keyboard. The reason for this is that many manufacturers have had difficulty controlling the embossing processes of polyester and as a result have chosen this relatively easy-to-use solution.

Metal domes can be used when no embossing is required in the overlay, or when demands are made for a different type of embossing than raised keys. If there is no need for more than a few keys, it can be of economical advantage to use metal domes, as the price of these is proportional to the number of keys. The method is also recommendable in cases where a large number of keys are desired within a limited area because the polyester film can only be "stretched" to a certain point. This obviously represents a limitation in the number of polyester domes that can be embossed in the overlay.

We guarantee up to 1 million operations on both dome types.

LEDs

In some designs, it may be useful to incorporate LEDs in the keyboard.

We use a special assembly method with conductive glue with our LEDs, which ensures that the LEDs do not loosen - neither during installation or later use.

To ensure room for the LEDs in the keyboard, the LED window is embossed in the overlay. This embossing simultaneously acts as a lens that spreads the light at a very wide angle.

Humid / Outdoor environments

When developing and constructing keyboards for use in very humid or outdoor environments, we always take the possibility of silver migration into account, which can be caused by moisture penetrating the keyboard.

The moisture attacks the conductive silver which then slowly dissolves. The result is usually missing key function or short circuiting of the keys due to loose silver particles inside the key. This problem is met by printing graphite on all "open" silver circuit. The remaining silver circuits are insulated with UV curing coating. Additionally there should be a closed “filler-ring” around the entire keyboard.

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EMC / ESD Protection

To protect against emitting - EMC / ESD - the top contact layer can be printed an additional silver shielding that can be grounded.

LED and display windows can be shielded with a clear conductive film, which integrates with the remaining silver shielding using a unique technique. This solution is specifically suitable for displays with high resolution, since the film does not create visual disturbances, in contrast to other methods.

Testing

All our keyboards are tested 100% for electrical errors and marked with unique ID numbers before shipment.

Choice of materials

The material selection for the keyboard always matches the individual design and keyboard usage.

The overlay for keyboards with domes is produced on polyester film, as materials like polycarbonate cannot withstand mechanical impact for longer periods.

The adhesives are always acrylic based. This ensures that the glue does not "sweat" or dries out even under extreme conditions. The rear adhesive can be varied and is always adjusted to the material and surface on which the keyboard is mounted.

We always recommend material selection in consultation with us.

Back panel

We can provide complete solutions where the keyboard is mounted on back panels of plastic or metal.

Acrylic plastic sheets, polyester or polycarbonate up to 5 mm are produced in-house. Metal plates are produced according to your drawings and instructions by some of Denmark’s leading metal sheet metal manufacturers.

Of course, you can also choose to deliver your own back panels - and leave the mounting of the keyboard to us.

We continuously develop and improve our keyboards. If you have any special wishes or requirements, simply get in touch with us and together we will then find the optimal solution according to your requirements.

The possibilities are many, and it can be difficult to assemble the right materials. We have more than 30 years of experience in design, construction and production of membrane keyboards

Take our advice from the beginning – this always ensures the best results.