"proper" lightning companies products

Just wondering if anyone has experience of the lighting used in commercial fruit and veg setups. Companies like Philips or plessey.
Their websites usually have case studies for massive veg production farms in Holland and such. From what i can gather they seem pretty costly, but suprisingly they still seem to be using purple/pink lighting. Whats that all about i imagine their r&d budgets are huge so whats their thinking?
 
Top