CREATING CONNECTIONS BETWEEN HUMAN AND MACHINE
Capacitive Switches Introduction
Capacitive switch is a kind of widely used interface touch control switch, which uses the electric field induction principle of human body to work, and is mainly used to replace the traditional mechanical switch. For example, capacitive touch switches from manufacturers like LuphiTouch, with integrated high-resolution touch detection modules and dedicated signal processing circuits, automatically identify and track environmental changes, are adaptable, no moving parts wear out, and can be programmed to adapt to the environment. Compared with mechanical switches, the advantages of capacitive touch film switches include: avoiding the use of physical contact, resisting the invasion of dust and water vapor, having higher reliability and durability, and better touch feel. In addition, the capacitive touch film switch can also be used in remote control, lamp dimming, various switches and vehicle, small appliances and home appliance control interface applications, and provides 8 LED drivers and 16 step optical controller. Capacitive touch film switch can effectively improve the user experience, and has unlimited life, can completely eliminate safety risks, and beautiful appearance, fashion.
LuphiTouch specialized in capacitive switches design and manufacturing for many years. We have had a lot of experiences in this industry and can customize the capacitive membrane switches, capacitive sensing circuits, capacitive covers, capacitive front panels etc. for our end clients which from medical, beauty, IoT, consumer electronics, intelligent kitechen, smart home etc. industries.
● Capacitive touch switches have many advantages, such as good durability, simple operation, the ability to detect multiple fingers and recognize gestures. However, the stability and cost of capacitive touch switches may have a certain impact on their promotion and application. In the design and use of capacitive touch switches, it is necessary to pay attention to material selection, layout design, installation and other factors to ensure its stability and service life.
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● Capacitive touch switches use the same technology as smartphone touch screens. They detect objects near the switch by using an electric field. The switch can measure the capacitance change generated by the user's finger, which causes the switching action.● Capacitive touch switches have many advantages over traditional push-button switches. The function of the touch switch requires no physical operation, which means no moving parts will wear out. Another advantage can be seen in the adaptability of capacitive touch switches, which, unlike conventional switches, can be programmed to adapt to the environment.● The increasing popularity of smart home technology provides a good example of the practicality of touch switches. Smart home control devices can be equipped with capacitive touch switches to control a variety of applications, such as heating, lighting and security systems. The action of each switch can vary depending on the system being controlled.● Touch switches can be manufactured using several different techniques, either on a traditional printed circuit board or on a flexible circuit board such as polyimide or polyester. The choice of substrate depends on the intended application and will greatly affect how the switch is installed.
- ● The first capacitive touch switch used indium tin oxide (ITO), a conductive alloy that can be deposited as a transparent film. This makes it ideal for touch switches that are backlit by light-emitting diodes (leds). However, with the increasing focus on capacitive touch switches, ITO's shortcomings have become more important. First, it is fragile and inflexible. This means that it is difficult to adapt to the complex shapes commonly found on modern consumer devices.● Secondly, ITO uses the subtraction method, so the manufacturing cost is high. In the subtraction process, the deposited layer of ITO is chemically etched to create the circuit required for the switch. This both wastes material and requires additional steps in production.● Due to the inherent limitations of ITO in the new design of capacitive touch switches, manufacturers began to seek alternative solutions that should provide good transparency and conductivity while providing a cheaper and easier to process product. One alternative that has been identified is composites that include conductive polymers.
Organic polymer
PEDOT is a polymer of EDOT (3, 4-ethylenedioxythiophene), a material that has emerged as one of the frontrunners in the race to replace ITO in capacitive touch switches.
PEDOT is an organic polymer that has several advantages over ITO, including simple molecular structure, small energy gap, and high conductivity.
In contrast to the subtraction method used to create ITO circuits, PEDOT is deposited on a cheap polyester film by additive method, which is a more efficient use of the material and a more environmentally friendly method, making the combination of PEDOT's conductivity and transparency superior to other polymers in switching applications.
However, making PEDot-based devices truly the ultimate innovation is an advance in the field of low-temperature welding. Conventional welding processes that use high temperatures are completely unsuitable for attaching chips and other electronic components to polyester circuits, and low-temperature technology means that such devices can now be attached directly end-to-end to polyester substrates.
PEDOT materials do have limitations. It is recommended that PEDOT be used only on transparent areas of polyester substrates. However, PEDOT circuits can be used in combination with silver conductive inks using a similar additive manufacturing process. PEDOT and silver ink can be combined to form a complete circuit. Thanks to this flexibility, different functions can be integrated into a single device, including discrete switches, slide switches, and knobs. In this way, a single capacitive switch can replicate the functions of multiple mechanical switches.
One of the advantages of capacitive touch switches is the ability to combine them with LED backlit displays. Leds are readily available and generate little to no heat, making them ideal for backlighting touch switches. They can be used to create attractive, intuitive displays that provide a positive user experience.
The backlit capacitive touch switch and its easy-to-configure features provide a cost-effective alternative to more expensive touch screen interfaces, while saving space through the use of multiple mechanical switches and buttons.