Speaking from a photographic background - The angle of incidence equals the angle of reflection (off of most reflective metallic surfaces). Which means if you shine a light 45 degrees on a surface, it will reflect 45 degrees in the opposite direction. This is true even with matte surfaces but with the irregularity of the surface, light is reflected in other directions which makes most objects plainly visible in most directions.
Reflective material works differently because the light is reflected right back at the light source because there are, in some, glass beads that not only reflect light off the curved outside surface but also the inside curved surface. When the light reflects off the curved inside surface the spherical shape of the tiny glass bead focuses the light like a lens on a spotlight. Beyond that, my knowledge of reflective fabric gets a little hazy but I suspect there are glass fibers or synthetic fibers that as a material is transparent, but when draw into fibers, its surfaces act like glass beads. I hope this helps. Darryl --- On Sat, 12/13/08, Dorothy Krause <[email protected]> wrote: > From: Dorothy Krause <[email protected]> > Subject: Re: [Bikies] Bike light discussion > To: [email protected] > Date: Saturday, December 13, 2008, 12:02 PM > Speaking of low and moving... reflective materials on pedals > and shoes are > what is most visible to me from my car. Ankle straps and > such work well too. > It's the movement that catches the eye first. That > includes blinking lights > also. The more, the better, in most cases. > > If people haven't found this out... Habitat ReStore > almost always has > reflective vests available for a few bucks. (They get a lot > of protective > clothing donated from industries.) I've suggested to > the manager that they > should offer them for half price to anyone bringing in > their bike helmet. So > far she hasn't bit on that one. > > Question from an earlier post... with reflective materials, > what kind of > angles does it reflect to? If you shine a light from above > onto something, > will it effectively light it up in a way that someone at > more then, say, a > 45 degree angle from it will see it, or does it mostly > reflect back in the > direction of the light source? A question I've really > never considered > before. > > Dorothy > > > > On 12/13/2008 11:22:12 AM, Troy Thiel ([email protected]) > wrote: > > While most of the conversation has been about > reflectors and lights on > > the front and back, for your night bike I'd highly > recommend > > reflectors that attach in the rims...so every rotation > is movement, > > the same is true on some rims as well as tires...heck > if I was Trek or > > other companies creating urban bikes I'd include > reflective materials > > into the paints and treatments of moving parts to help > the cause! > > > > should we bikies begin a movement for a free light > program? I'd also > > consider adding to said movement free helmets, > especially for kids who > > don't ride them and improving the City's Bike > Safety materials..they > > could use an upgrade! > > > > Count me in on the first group meet to consider. > > > > Ride safe, (I can't > > still nursing a sprained ankle..argh) > > Troy Thiel > > _______________________________________________ > Bikies mailing list > [email protected] > http://lists.danenet.org/listinfo.cgi/bikies-danenet.org _______________________________________________ Bikies mailing list [email protected] http://lists.danenet.org/listinfo.cgi/bikies-danenet.org
