ITO in displays
Indium Tin Oxide (ITO) is a clear substance that can be coated to glass, plastics and thin films. As well as remaining fully transparent, the substrate will also become electrically conductive. This technology is used in a variety of applications, but perhaps none more so that ITO in displays.
As ITO Coatings are transparent, there are many uses within display applications, from large format retail displays and touch activated ticketing kiosks (when you last bought a train ticket from a kiosk, you were probably enjoying the benefits of ITO film), and of course the touchscreen on your mobile device.
The 2 most prominent examples of ITO in displays would be in the manufacture of both capacitive and resistive touchscreens. We will outline below how each form of touchscreen is used – there was an example of each in the paragraph above.
Technology of ITO in displays
The material providing this conductive layer not only has to be transparent, very fine and highly conductive, it also has to be robust enough to withstand challenging environments and high usage.
Capacitive ITO Coated Touch Screens
Capacitive Indium Tin Oxide Touch Screens are used mostly in domestic smartphones, tablets and PCs. A thin layer of ITO is coated to the screen surface and uses the charge found in a users touch to register location and gesture of that touch. Capacitive screens have visible transmission rates of around 90%, which is higher than that of resistive screens (approximately 70%).
Diamond Coatings uses index matching technology to manufacture capacitive ITO coated touch screens featuring visible transmissions equalling those of uncoated glass or plastic.
Resistive ITO Coated Touch Screens
Resistive ITO coated touch screens work slightly differently. Underneath the screen, there will usually be a thin film that works of the pressure of a downward touch. As the film is conductive, there will be a break in charge where the touch occurs. This makes resistive screens a great choice for more public facing touchscreens, such as an ATM. The heavy use aspect is protected more using a film within the display, as opposed to the surface of the display. We can supply X-Y resistive, ready-to-use touch screens complete with patterning, bonding and connections and also offer ITO touch screens that are fully shielded.
Both capacitive and resistive ITO displays have their place in the market offering different features that work better in certain environments.
When you think about it, it is probably nearly impossible to go through a day without using ITO in displays in some instance.
If you would like to know more about our ITO in displays capabilities in more detail, get in touch with us today.