It is not something that can be answered in only one line. The iPhone display is made of several parts which come from different types of materials.
To understand how iPhone screens are made, we need to see the elements of the display in the particular iPhone device.
Tempered Glass
Tempered glass is the top layer that you usually touch with your fingers. It is the outer layer of the display of the iPhone that interacts with the users directly. The glass comes with an oleophobic coating to make the users’ fingers easily slide. Tempered glass is usually replaceable, and users can replace it by themselves.
A transparent layer of glue
Between the matrix and the tempered glass, there is a transparent glue. It does not only stick the tempered glass to the matrix, but also removes the air gap and makes the layer denser. The good quality of the adhesive layer will not disrupt the clearness of the glass.
Touchscreen
A touchscreen is also called a touchpad or sensor. It is the reactive part of the users’ touch. It is made of a thin layer of glass which facilitates the multi-touch technology.
Polarizing filter
It is a special layer which makes the matrix image visible to the users’ eyes. That’s why it is called a polarizing filter. This will translate into something that the human eyes can see. Without this layer, we can’t see anything on the screen.
Matrix
The Matrix comes with two plates.
Between the plates, there are liquid crystals which are responsible for passing the beams of light through themselves. These are called backlights.
It is a structure that the IPS matrix is used in all models of the smartphone. Apple has developed this technology for years.
Backlight
It is the light source which will make the visual visible. It creates light to back the crystals so that the images will be visible. The source of light is very important for turning on your display screen.
Additional sensors
There are sensors in the display of the iPhone. It is used to read the tap pressure on the display. It provides an accurate measurement of the distance from the finger to the matrix. These additional sensors are responsible for the technology behind the 3D Touch feature on the modern smartphone.
Frame
The frame is all above the elmeents. It is installed directly on the framework of the iPhone. It is where the creators place all of the layers of the components which the thickness is only millimeters.