A preferable metal foil is of aluminum or stainless steel in a thickness of 10 to 20 μm having {HEAD ~ a total reflection rate} of 80% or more, against {TAIL ~ a tungsten lamp} 
against
A preferable metal foil is of aluminum or stainless steel in a thickness of 10 to 20 μm having { HEAD ~ a total reflection rate } of 80 % or more , against { TAIL ~ a tungsten lamp }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL