Our solar vacuum tubes has prosperity of high absorption and low emission. The vacuum tube consists of outer tube, inner tube, (al-n-ss-cu) coating and holder.Al-nn-ss-cu is coating for three target tube. Three target assimilate the advanced 12 layers of spattering deposition of trivalent element technology, high borosilicate glass, and gradual change of al-n-ss-cu selective complex absorptive coating. These make three target vacuum tube have high performance of absorption and low reflection ratio. Because of the coating, three target vacuum tube’s absorption rate increase 30%-50% than normal tube.
