Are IPS screen LCD better at producing colours? Because when you look at a non-IPS screen on a Macbook Air and compare it to a IPS on the non-retina Macbook Pro it looks that way. But is that really the case? Can LG and Panasonic IPS LCD produce better colours?
Only the Retina MacBook Pro is using an IPS panel.
Neither the MacBook Air or the non-retina MacBook Pros are using IPS - though I believe the MBP's panel is higher quality than the one used in the MBA.
It's more to do with the quality of the panel and its backlight, than the panel itself. There are many non-IPS displays which have color reproduction as good or better than the best IPS panels.