Short answers, pulled from the story.
A liquid-crystal display, or LCD, is a flat-panel display that uses the light-modulating properties of liquid crystals combined with polarizers to show information. Liquid crystals do not emit light themselves, so they rely on a backlight or a reflector. Applying voltage twists or untwists the crystals to control how much light passes through each pixel.
George H. Heilmeier built the first operational liquid-crystal display at RCA using the dynamic scattering mode, and he was inducted into the National Inventors Hall of Fame and credited with inventing the LCD. The twisted nematic field effect was filed for patent by Hoffmann-LaRoche in Switzerland on the 4th of December 1970, with Wolfgang Helfrich and Martin Schadt named as inventors.
The first wristwatch with a TN-LCD was the Gruen Teletime, launched in 1972 with a four digit display. Brown, Boveri and Cie produced twisted nematic displays for wristwatches through the 1970s after licensing the technology from Hoffmann-La Roche.
Twisted nematic (TN) panels are inexpensive and fast but have narrow viewing angles and limited color accuracy. In-plane switching (IPS) aligns the crystals parallel to the glass, costs more, and has become the benchmark for color accuracy and reliability, driving nearly all LCD smartphone panels. Vertical alignment (VA) offers deeper blacks and a higher contrast ratio than TN but slower response times.
In 2007 the image quality of LCD televisions surpassed that of cathode-ray-tube TVs, and in the fourth quarter of 2007 LCD TVs outsold CRTs worldwide for the first time. LCD screens replaced CRT displays in nearly all applications from the late 2000s to the early 2010s.
LCD production uses nitrogen trifluoride (NF3) as an etching fluid for thin-film components, and NF3 is a potent greenhouse gas with a relatively long half-life. A report in Geophysical Research Letters called it the missing greenhouse gas, and it was later added to the Kyoto Protocol for the second compliance period during the Doha Round. Critics noted that two earlier studies found only 2 to 3 percent of the gas escapes destruction after use.
By the 2020s China became the largest manufacturer of LCDs, with Chinese firms holding a 40 percent share of the global market. Companies including BOE Technology, TCL-CSOT, TIANMA, and Visionox raised production, aided by local government investment. The industry had earlier shifted from Japan to South Korea and Taiwan in the late 1990s.