| 摘要 |
<p>The object of the present invention is to prevent the generation of cracks on a frit sealer without determining a precise amount of the frit sealer and increasing the wall thickness of each capillary. For achieving the object, the capillaries 3 are formed of a material doped with an amount of magnesium oxide which is substantially 20 times greater than that of a center body 2 having a light emitting space provided therein and then pre-baked at 1200 DEG C. The capillaries 3 are joined to the body 2 and both are baked again at 1200 DEG C. Finally, both are baked at 1850 DEG C for three hours under the hydrogen atmosphere. As a result, the average diameter of alumina grains in the capillaries 3 is 19 micrometers, smaller than that, 32 micrometers, of the center body 2, hence increasing the physical strength of the capillaries 3. <IMAGE></p> |
