Does it ring a bell when I say membrane keypads to you? You will probably give me a shrug. But what if I ask have you ever pressed any soft-touch button on the electrical or electronic devices instead? Now you would definitely say yes. In fact, these little buttons on the panel work as user interfaces to connect a user with the device. They have been evolving for decades of technology improvements. To be specifically speaking, today it is well-known as the membrane switch industry. Different types of membrane switches have been developed because of their broad applications. You could basically see these user interfaces anytime wherever you go. Generally, they are mainly classified as two types of membrane switches, tactile membrane switch and non tactile membrane switch.
Before we decide, let’s get to know the tactile membrane switch and non tactile membrane switch first.
1. Tactile membrane switch/tactile switch keypad
1.1 Why do we call it tactile membrane switch?
Tactile membranes are momentary, which means you need to push the tactile buttons to get it to work. Named as the tactile membrane because there is a tangible feel when users press these buttons. So it gives very strong snap feedback to the user. This tactile response is normally from the domes sitting under the graphic overlay. There are mainly two kinds of domes, one is the stainless steel metal dome, another is polyester dome. The poly domes are more cost effective, but the stainless steel domes are preferable. After all, the metal dome is the best way to get a clear snap and tactile feedback. But the more tactile buttons required, the more cost the tactile membrane switches will take.
When pressed, the metal dome deforms to connect the secondary pathway to get the circuit closed. While the pressure is off, the metal dome will snap back to its relaxed state with the circuit open. Though it happens very fast, still the haptics feedback for users can help to confirm the actuation.
1.2 How does a tactile switch keypad provide the precise finger location?
Usually embossing is the common way of displaying the right finger location. It can give the graphic overlay the aesthetic look as well as the function purpose. Highlight the key area by raising the surface of the overlay. And polyester is preferable. Meanwhile, with colored symbols, it can help the finger to push in an accurate location.
1.3.1 It provides better user experience, especially in a noisy environment.
Because of the stainless steel dome, the end-user benefits from the snap action. You can consider it as an indication that whether tactile switches are activated or not. It is reliable and dependable. A strong tactile snap is more effective than the auditory signals in a noisy environment.
1.3.2 It can be durable in high temperatures.
The tactile membrane switches with metal domes have better durability at high temperature. As the stainless steel domes are quite physically stable even in extreme temperatures. For those with poly domes, or embossed buttons on the graphic overlay, are not suitable for temperature above 50°C. The life cycle of the tactile switch is shorter than non tactile membrane switch. it still can be up to 1 million actuations. It is far more enduring than other traditional switches.
1.3.3 It is moisture and dust resistant.
Tactile membrane switch is internally vented. And it seals from the top – graphic overlay to the bottom – Rear adhesive. Not a bit of exposure to the exterior environment. So the moisture, dirt, and contamination can’t get in. The dust can never load a lot on the overlay compared with mechanical switches, thus it is very easy to clean.
2 Non tactile membrane switch
2.1 What is a non tactile membrane switch?
Non tatctile membrane keypad is flat and thin, with the circuit layer printed on a sheet of plastic. And when you press the keys on the graphic overlays, there is no solid response for the users. In other words, you could barely have tactile feedback. And it means you could activate the switch without any notice. So we need some other ways to inform our users to confirm the activation. The membrane user interface designs include an audible sound like a beep, or an optical change or a signal with an LED light or LCD screen.
Unlike the tactile membrane, there isn’t any metal dome or poly dome in the non tactile membrane switch. Thus, the non tactile switch requires the keys to have high sensitivities. When pushed, the silver point from the upper layer makes a contact with the circuit below to start activation.
According to various switch designs, the keys on the membrane keypad can be flat or embossed. Embossed keys could help fingers to locate. Any shapes and sizes of non tactile membranes are available for customized needs.
2.2.1 It is more durable and cost effective.
Non tactile membrane switch has a different structure from the tactile membrane. Non tactile has a more reliable structure and all parts are sealed from the exterior environment. So it has a higher durability and longer-lasting life cycle. And it is competent for over 1 million actuations. Plus, due to its easier process, non tactile membrane is cost effective and affordable.
2.2.2 Its user interface is more user-friendly for poor light surroundings.
Non tactile membrane does not have any stainless steel domes to get tactile feedback to the user. So the feedback for users depends on the embedded LED light or optical backlighting. And these switch designs are ideal choices for the poor light conditions. You can locate the keys on non tactile switches easier with backlighting, even when you are in a very dark place.
2.2.3 It responds rapidly.
Non tactile membrane switch responds very fast. With a very gentle press, the circuit layer will be actuated immediately and start to work. Technically, you can actuate these switches within 0.05 seconds. Basically, it depends on how fast your fingers run over the keys. What’s more, an extensive range of actuation forces are available too.
2.2.4 It is safe and easy to clean.
Thanks to its flat surface and dustproof design, non tactile switches are easy to clean. And no special maintenance is in need. What’s more, all the electronic components are completely sealed from exterior surroundings. With good protection, the tactile membrane is totally moisture-proof. You can use it with wet hands without worrying about electricity leakage.
You definitely have a better understanding of tactile and non tactile switches now. In practice, tactile membrane is ideal when requiring a discrete operation. And non-tactile is perfect for the use that required more durability with less cost. Tactile switch keypad and non tactile switches are both used in various fields. For example, appliances, game devices, electronic products, industrial machines, medical and army devices.
HuaiSong Industrial is capable of offering varied types of membrane keypads/switches. We have both tactile and non tactile switch keypads available. To find out which one suits your needs the most, please contact us.