| 摘要 |
In the light bulb including a filament and having on one or two side faces a light interference film consisting of alternative layers of low and high reflectances. The low reflectance layer includes silica as the main component with phosphorus and boron. The sum of P and B of addition is within 3-20wt.% in conversion to P2O3 and B2O3. The high reflectance layer consists of titanium oxide, tantalum oxide, zirconium oxide, or a mixture of two or more of them. The adjustment of thickness of the coating for interference allows selective reflection of light rays desired.
|
