Why would it take a "source" to see what's readily evident from looking at any headlight design? Have you figured out yet how 40% of the light could be trapped in said any? Seem rather obvious that anyone who can at least point to the obvious is not the equal of those who have a real hard time with it all, and the subsequent conversation would be one of spoon feeding rather than where rules of debate might apply.
It's curious why you don't quote my posts in your replies. It's worth elaborating that I don't use technical words at times out of coincidence but so that googling them will produced sufficient explanation to avoid said spoon feeding, for readers of marginal ability at least. In the case notice the previous references to the applicable optic types, which should produce some efficiency ranges, the only one of which is close to 40% are TIR optics used in led systems. Also worth pointing out that someone previous in the thread even gave you reflector loss numbers, so it makes sense why basic research was well out of ability here.