What is the interface that connects the TV LED screen to the PCB
Unfortunately, there's all kinds of different connection schemes (manufacturers like to lock you in). Tye most common ones are parallel (D.P.I.) which is just a data line for each bit of colour data (eg. 8 lanes for green, 8 for red etc.) and LVDS (FPD link? among others) which wraps up all the important data into a block and sends the block out over, I think 7, high speed lanes (which can sometimes be paralleled up to run higher resolution displays). Both of these also don't have standardised pinouts or cables, there's 20pin, 30pin, 40pin lcd cables carrying all kinds of formats (there's also DSI, which is mainly found in tablets and smartphones, embedded display port is sometimes used as well). Sorry if this just rasies further questions, but there really is a whole slew of different connection methods.