You know cellphones, but do you know what are cellphone' s LCD and Digitizer?

Cell Phones and Tablet PCs are part of our daily life now. We use them everyday, can't leave it for even one day. So it looks like we must be familiar to them. We all know that they are made up by LCD and digitizer. But do you really know what LCD and digitizer are?

What is a LCD?
The LCD (Liquid Crystal Display) displays the image on your phone using the same technology as most flat screen TV's. LCD units are generally very fragile and susceptible to damage.
Common faults / issues with LCDs include:

• Screen looking washed out, very dull colours and less clarity then usual 
• Dead pixels - When a  pixel on the LCD no longer works, usually visible on a white background it will be a tiny black square
• Stuck Pixel - When a pixel is stuck on a colour, usually visible on any background and will generally be stuck on white, green, blue or red.
• No backlight - When the back light on the LCD fails the picture can be very hard to see.
• Lines on the LCD - these can be a verity of coloured lines displaying horizontally or vertically 
• Damaged LCD, generally damaged LCDs can be bruised, cracked or "bleeding" when a black liquid is visible over the picture
• In modern touch screen devices digitizers are fitted over the LCD and respond to touch, these are separate to the LCD, replacing the LCD wont cure issues with the touch panel.

What is a Digitizer?
The Digitizer is the touch panel that sits over the LCD screen. The digitizers job is to detect and map your fingers movements across the screen and let the phone know where your finger is.
The digitizer panel is a clear panel, usually bonded underneath or inside the front glass or plastic the sits on top of the LCD, they rarely malfunction but are very susceptible to impact damage, scratches and cracks
Common faults / issues with digitizers include:

• Touch panel no longer responding - if you can se the picture ok but the device is not responding to touch
• Touching the panel causes unexpected or erratic movements - this will require a replacement digitizer or re-calibration is available on the device 
• Impact damage - glass digitizers are very easily damaged, generally the will crack or shatter - depending on the extent of the damage it may still work but in not advisable due to safety.
• Scratches - plastic digitizers are very susceptible to scratches, several light scratches build up making the phone look tatty and harder to view

References: http://www.replacebase.co.uk/apple-iphone-5-lcd-touch-screen-digitizer-assembly-with-frame---black-3220-p.asp