Retina display - online puzzles

Retina display

The Retina display is a branded series of IPS LCD and OLED displays by Apple Inc. that have a higher pixel density than traditional displays. Apple has registered the term "Retina" as a trademark with regard to computers and mobile devices with the United States Patent and Trademark Office and Canadian Intellectual Property Office. The applications were approved in 2012 and 2014 respectively. The Canadian application cited a 2010 application in Jamaica.

The Retina display debuted in 2010 with the iPhone 4 and the iPod Touch (4th Generation), and later the iPad (3rd generation) where each screen pixel of the iPhone 3GS, iPod touch (3rd generation), and the iPad 2 was replaced by four smaller pixels, and the user interface scaled up to fill in the extra pixels. Apple calls this mode HiDPI mode. In simpler words, it is one logical pixel that corresponds to four physical pixels. The scale factor is tripled for devices with even higher pixel densities, such as the iPhone 6 Plus and iPhone X. The advantage of this equation is that the CPU "sees" a small portion of the data and calculates the relative positions of each element, and the GPU renders these elements with high quality assets. The goal of Retina displays is to make the text and images being displayed crisper.The Retina display has since expanded to most Apple product lines, such as Apple Watch, iPhone, iPod Touch, iPad, iPad Mini, iPad Air, iPad Pro, MacBook, MacBook Air, MacBook Pro, iMac, and Pro Display XDR, some of which have never had a comparable non-Retina display. Apple uses various marketing terms to differentiate between its LCD and OLED displays having various resolutions, contrast levels, color reproduction, or refresh rates. It is known as Liquid Retina display for the iPhone XR, iPad Air 4th Generation, iPad Mini 6th Generation, iPad Pro 3rd Generation and later versions, and Retina 4.5K display for the iMac.Apple's Retina displays are not an absolute standard for display sharpness, but vary depending on the size of the display on the device, and at what distance the user would typically be viewing the screen. Where on smaller devices with smaller displays users would view the screen at a closer distance to their eyes, the displays have more pixels per inch (PPI), while on larger devices with larger displays where the user views the screen further away, the screen uses a lower PPI value. Later device versions have had additional improvements, whether an increase in the screen size (the iPhone Xs Max), contrast ratio (the 12.9" iPad Pro 5th Generation, and iMac with Retina 4.5K display), and/or, more recently, PPI count (OLED iPhones); as a result, Apple uses the names "Retina HD display", "Retina 4K/5K display", "Retina 4.5K display", "Super Retina HD display", "Super Retina XDR display", and "Liquid Retina display" for each successive version.