The 77-inch display has 40 percent transmittance and 80R curvature, or can be curved into a circle with a 80mm radius.
Equipment makers, which also took part in the project, have developed optimised kit for mass producing the transparent and flexible displays. Software partnered also developed user interfaces for signage, smart desks, displays for cars, augmented reality applications and more, the firm said.
LG first made an 18-inch flexible OLED display, as well as a separate transparent display in 2014.
In 2015, the company announced the development of an 18-inch "rollable" display that boasts a curvature of 30mm.
Last year, it made a 55-inch display with a transmittance of 40 percent.
Rival Samsung has similarly shown off its own transparent displays.
Google is also reportedly investing in LG Display to get supply for small-sized flexible OLED displays to put in its next Pixel phone.