The most basic model is the 20" IPS206T, this monitor has a 1600 x 900 pixel resolution, 6ms grey-to-grey response time, 5,000,000:1 dynamic contrast ratio, 178-degrees viewing angles, and VGA/DVI-D outputs.
The 21.5" IPS226V has quite similar specifications, except that it has a 1920 x 1080 pixel resolution and an additional HDMI output, and the IPS236V delivers the same specifications in a 23" form factor. The 23" IPS231P with two built-in 2W speakers has the same resolution and screen specifications, it seems to lack HDMI but it's the only of the four screens that offers an adjustable stand.
The LED backlight helps LG reduce the depth to just 19.5 mm and the energy consumption has been decreased by 27 %. LG has not mentioned if we are looking at Edge lit LED models or backlit LED but the very slim design could suggest that these are Edge LEDs.
IPS2062T, IPS226V, IPS236V and IPS231P come in 20”, 21.5”, 23” and 23”, respectively. All (except for the 20” IPS2062T) has a Full HD 1920x1080 panel and a 6 ms response time. The IPS monitors also have a 5.000.000:1 dynamic contrast ratio, 250 cd/m2 brightness and 178/178 viewing angles.
Source: FlatpanelsHD