Here are the most commonly asked questions about touch screens.
Are touch screens produced at Butler Technologies?
The design of the touch screen can determine if BTI or an offshore partner would be best suited. Our in-house engineers will be there at every step to assist in touch screen design. Most of the touch screens are produced by our offshore partner.
What are the different kinds of touch screens?
There are technically four different kinds of touch screens within the line of BTI's capabilities.
- Resistive Touch Screen
- Projective Capacitive Touch Screen
- Capacitive Touch Keypads and Buttons
- Planar Touch Screens
What are the main advantages of using a touch screen compared to traditional interfaces?
- Accurate and fast response
- Use with bare finger or stylus
- Easy to clean
- Adds a modern and innovative design to products
- Durable and resistant to harsh conditions
What is the difference between Resistive and Capacitive Touch Screen?
The first reason why the resistive touch screen is different from the capacitive touch screen is that the physical stack up of the resistive touch screen is more complicated than the cap touch screens.
Resistive touch screens are typically cheaper than their counterparts and can work with nonconductive stylus pens and gloves. Resistive touch screens only rely on the force, conductive or not; the power will be enough for the touchscreen to work.
Since cap touch sensors rely on conductivity to act, they are more touch-sensitive. Projective capacitive touch screens work by emitting an electric field above the screen. Once a finger gets close to the screen, the chip connected to the tail reads that a conductive force has interrupted the electric field.
What are the main advantages and disadvantages of resistive touch screen technology?
Advantages are low production costs, low power consumption, high resistance to dust and water, actuated by bare finger, gloved hand, or stylus, and suited for handwriting recognition.
Disadvantages are that an activation force is required. Unlike a capacitive touch screen, it does not support multi-touch, lower transmittance, overall optical quality (due to increased number of layers), and is less durable than other touch screen technologies.
Are there different resistive touch screen designs to choose from?
There are 4-wire, 5-wire, 8-wire designs to choose from. The 4 wire design is the preferred solution for low-cost applications. The 5-wire is ideal for applications cost is still of primary concern, yet long life expectancy is required. 8-wire touch screens are the most accurate and auto-corrects for drift which eliminates the need for recalibration.
What are the different kinds of constructions of resistive touch screens?
The main two resistive touch screen constructions are film-to-glass and film-to-film. Flim-to-glass is used for applications requiring more transparency or needing a larger size, up to 21 inches. Flim-to-film structures have a higher cost and can be manufactured up to only 12 inches.
What is a Planar Touch Screen?
Planar touch screens work by adding an overlay, sometimes containing a membrane switch or other similar technology, to surround the touch screen. Typically planar touch screens are just resistive touch screens with an added layer of functionality.
What are the main advantages and disadvantages of capacitive touch screen technology?
Advantages are excellent clarity, more resistance to scratching, far more sensitivity than resistive touch screens, resistance to surface contaminants and liquids (dust, oil, grease, moisture), support multi-touch inputs (up to 10).
Disadvantages are more costly than resistive touch screens; sensitivity to EMI/RFI, in some, requires a bare finger or conductive stylus for operation.
What are the different kinds of constructions of capacitive touch screens?
There are three kinds of capacitive touch screen constructions, film-to-glass, glass-to-glass, and glass-to-film plus film. The film-to-glass structure is the cheapest option but can only be up to 12 inches in size. Glass-to-glass offers high transparency, can be made up to 21 inches, and is the most popular PCAP construction.
What are the common materials used in touch screens?
Film for Top and Bottom Layers (Circuits)
- Clear or anti-glare, hard-coated film (.007″)
- Clear or anti-glare, the hard-coated film with anti-Newton Ring Coating (.008′)
- Films have ITO coating on the non-hardcoat side.
Glass for Bottom Layers (Circuits)
- Standard conductive ITO-coated glass
- Thickness: 0.55mm, 0.7mm, 1.1mm, 2.0mm, and 3.0mm
- Thinner glass offers better transparency.
- More surface unevenness with thicker glass.
- Chemically strengthened conductive ITO glass.
- Thickness: 0.55mm, 0.7mm, 1.1mm, 2.0mm, and 3.0mm
- Greater impact and break resistance.