The title says it all. Do any of you lighting gurus know what the reflectivity of a reflector is? I'm pretty much finished with my project and made it look pretty much as OEM as it gets. However, I there's a nice gash in my highbeam reflector side. Instead of spending a huge wad of cash for a new housing and redoing the whole project (which took me forever), I decided to get it coated instead. Hence, the question. Is it 75%? 80%? 90%? Also what is the reflectivity of projector unit itself? Don't really care which one. Thanks.

Mike

The degree of reflectiveness varies from headlamp to headlamp. It is one factor that designers use to accomplish desired output. According to my logical sense, a less reflective mirror will lower peak intensities and make transistions softer. In todays multi mirror reflectors there are 80-200 "internal mirrors" that has to align up to a correct beam pattern without streak.

Herman - what your best guesstimate in terms of reflectivity? I have a smooth transition reflector so I don't have to worry about the internal reflectors. Thanks.

Here's a how-to on measuring reflectivity:
http://www.prairieastronomyclub.org/reflect.htm

If 60-90% is the range, I'd guess 90% for a quality (non US, non Asia) reflector based headlamp.

Where are you getting it re-aluminized or re-chromed?

I'm an optical engineer so I have a few sources of getting them coated, I'm not sure which one I'm going to go with, whoever is cheaper I guess (since I'm paying for this and not my company).
As far as reflectivity, I measured the reflectivity of my reflector using a HeNe laser and a powermeter. What I noticed was that the reflectivity changes based on the angle I was pointing the beam so I need to find the sweet spot angle.

Also, I haven't checked into what the reflectivity of rechroming is as all my sources are optical companies that deal with AR coatings as well as aluminum coatings for mirrors and stuff for glass. I have to find out if these companies can do it for plastic. Also cost is a big issue, if it's too expensive, I'm going with the chrome spray can.