| 摘要 |
PURPOSE:To improve the cooling effect of face plate by filling the space between the face plate of projection tube and the space surrounded by a metal plate fixed at the front side thereof and the transparent plate with a liquid containing a propylene gricol. CONSTITUTION:A television picture projection apparatus is formed by fixing a metal plate 13 such as aluminium plate having a window at the center to the external surface of face plate 12 of projection tube 11 with a bonding agent 14 and attaching metal 15, fixing a transparent plate 19 such as a glass to the front side thereof with a bonding agent 20 and filling the hermetically sealed space 22 between them with a 100wt% propylene gricol as the liquid. The heat from the face plate 12 is transmitted to the metal plate 13 through convection of the liquid and is then radiated to the outside. Therefore, since the solidifying point of propylene gricol is sufficiently low, the convection occurs even in the cold region assuring good cooling property and thereby breakdown of projection tube can be prevented. |
