Screen of Mobile Phone or a Smartphone is one of the key features, user are concerned with when buying a new mobile device. Display screen is the main hardware that user can interact with the software and do various things. Display screen has been evolved and today humans reached the milestone of making flexible screens. There are lot of display types used in mobile phones.
screen components
Protector Glass
Protector glass covers over the mobile phone's display panel and touch panel, for protecting them. Generally, the protector glass's thickness is between 0.5mm and 2.0mm, for consideration of size, weight, touch feeling and transmittance conditions.
Touch Panel
touch- screens are typically found on larger displays, in phones with integrated PDA features. Most are designed to work with either your finger or a special stylus. Tapping a specific point on the display will activate the virtual button or features displayed at that location on the display.
LCD (Liquid Crystal Display)
    LCD is one of the major display technologies used in mobile phones. LCD display have low energy requirements and are generally easy to read. LCD panels generally consist of a grid of extremely tiny square areas called "pixels". Each pixel can be controlled to allow light to pass through, block it, or allow just a certain amount of light through. In a full- color LCD, each pixel contains at least three sub pixels ( generally red, green and blue) that can be individually controlled.
Frame Lamination
Using the double glue to fix the four sides of touch panel and display panel. This method is currently used by most of the display screen. Its advantages lie in the simple manufacturing and low cost, but due to there is an air layer between the display panel and touch panel, the display effect is greatly reduced after the light refraction. 
Full Lamination
    Full lamination is also called direct bonding, laminating display panel and touch sensor with water cement or optical cement in non-air gap way. Compared with frame lamination, it displays better:

Full Lamination Technology - OGS, On-cell & In-cell Screen Comparison


 Project Capacitive  OGS On-Cell(AMOLED) In-Cell (TFT LCD)
Concept Integrated touch screen with the  protection glass, on the protective glass medial plating ITO conductive layer. Directly coating and lithography on the protection glass  Embed the touch screen to display, between the display's color filter substrate and polaroid. As on the LCD panel match with touch sensors Embed the touch panel function into the LCD pixels. As embedded the touch sensors function into the screen

TFT LCD plus external hanging type OGS projected capacitive touch panel  (Total 3 piece of glass substrate) 


AMPLED plus On-Cell projected capacitive touch panel and protection glass(Total 3 piece of glass substrate) 


Embedded projected capacitive touch panel's TFT LCD(Total 3 piece of glass substrate) 
Advantage                       Light, thin, without air layer: In-Cell > On-Cell > OGS  
Defect Strength is insufficient, high cost, low yield Technology has not been able to overcome the light-weight, when touch the color is not equal Screen need to form a complete set of embedded touch screen IC, otherwise it will easily lead to wrong touch sensor signals or too much noise.  The threshold of the technology is quite high, low yield
Leading Party  Touch Panel Manufacturers  Display Panel Manufacturers 
Typical Model XIAOMI2 SAMSUNG, LG iphone5,Lumia920
Lamination Comparison
Lamination Method  Frame Lamination  Full Lamination 
Principle diagram  Principle diagram  
Advantages  Simple technology, lower cost, easier to repair when broken 
Better display effect 

  • 1. Fills the air gap with the optical clear adhesive between the touch 
    panel and the display panel (LSD or OLED)
  • 2. Anti-reflective and anti-glare treatment.
  • 3.98% visible light transmission
  • 4. Enhanced display performance
  • 5. Improves both indoor and outdoor readability.
Disadvantages  Bad display effect  Complex technology, higher cost, more difficult to repair when broken