This has become a common display type for mid-range to high-end phones. OLED/AMOLED. OLED & AMOLED utilizes 'organic' LEDs which emits light and in the majority of cases does away with the need for the back-light of an LCD display resulting in a potentially thinner panel.
1 The model number is located on a small label located on the frame around the computer screen. (e.g., VGN-FW550F)  The computer information and compliance label, located on the bottom of the laptop case, indicates the actual model number.
In Hardware Overview look for Machine Identifier or Model Identifier in newer iMacs. 5. When you have the identifier (for example: iMac7,1), use it to find your model from our list on the left. iMac (iMac15,1) Core i5 3.5GHz 27 inch (Retina 5K)