Overview
A capacitive touchscreen is not a true display but a separate component mounted above the LCD. Visually, the capacitive layer is a piece of transparent tempered glass.
These two components are not directly comparable because they serve different functions. Most smartphones incorporate both layers.
What is a capacitive touchscreen?
A capacitive touchscreen is transparent like glass; it does not display content or emit light. Its purpose is to detect user touch input.
What is a TFT LCD?
A TFT panel is the actual display. TFT is a widely used type of LCD suitable for mid- to low-end displays and is common in smartphones. A TFT LCD (thin-film transistor liquid crystal display) is a display panel that does not detect touch and is used only to show images.
How they work together
Modern smartphones typically stack both layers: the TFT LCD handles image rendering, while the capacitive touchscreen senses user input. This layered arrangement explains the terms "inner screen" and "outer screen".
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