Apple's 27-inch iMacs are expected to ship in three or four weeks and those tired of waiting can apparently blame LG Display for the delay.

The root cause of the 27-inch iMac delay reportedly lies in LG Display's mass production issues. As it turns out, the company is facing some problems with the full lamination process when producing the panels. Due to such issues, Apple can only ship 100,000 27-inch iMac units a month, compared to planned 300,000 21.5-inch iMac units.

The news of LG Display's production issues comes from a DigiTimes report citing unnamed "industry sources." The report further states that LG Display is expected to achieve better yields for the 27-inch units by February 2013.

Apple launched its latest iMacs back in November. The brand new iMac now sports a new design, improved display with significantly reduced reflection, third-generation Intel quad-core processors, NVIDIA graphics, as well as a new storage option dubbed Fusion Drive. According to the Cupertino-based company, the new iMac is the most advanced desktop Apple has ever made.

The new iMac is redesigned from inside out, boasting an aluminum and glass enclosure with up to 40 percent less volume than the previous iteration. Apple also touted that its new iMac has a completely re-engineered display that reduces reflection by as much as 75 percent, while managing to maintain color and contrast. The cover glass, meanwhile, is now laminated to the LCD, and the company has also applied an anti-reflective coating using a plasma deposition process. Moreover, every iMac is individually calibrated using a complex spectroradiometer, explained Apple.

The third-generation quad-core Intel Core i5 in the new iMac can be bumped up to Core i7, while the NVIDIA GeForce processors deliver up to 60 percent greater performance for gaming and graphics-heavy apps. While it all sounds pretty good, shipping delays are marring the iMac's appeal.

KGI Securities analyst Ming-Chi Kuo was the first to point out that the lamination process for the new iMac's screen would pose challenges, and warned about this way back in August 2012. The analyst suggested at the time that such challenges would result in a launch six to eight weeks later than the 21.5-inch iMac option. As it turns out, the predictions proved to be true.