Edited sentence: But in fact they were a version of a Schmidt-Cassegrain that delivers some advantages of the Ritchey-Chrétien design, such as a coma-free field, without all the associated cost.By March 2008, model designations for the RCX400 had been changed to "LX400ACF", for "Advanced Coma-Free".In January 2008, Meade settled the claim and agreed to quit using the initials RC in the name.Meade Instruments, of Irvine, California, introduced the RCX400 series of instruments in 2005, with mirror diameters of 10", 12" , 14" and 16", which they originally claimed were Modified "Advanced Ritchey-Chretien" Cassegrains.They were soon sued by makers of true Ritchey-Chretien telescopes because their "Advanced RC" design is actually a variation of SCT designs, and not directly related to the Ritchey-Chretien design.This line of scopes was later "suspended indefinitely", due to bugs in electro-mechanical components, but the ACF optics are now used in their LX200 and LX90 scopes (now known as LX200ACF and LX90ACF)