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Ceramic EL lamp

After appropriate surface treatment, the thin iron sheet is coated with a layer of transparent enamel melt, and then the coated iron sheet is heated to a red-hot level to melt the coating on the iron sheet to form a complete covering layer about 0.05 mm thick. The coating must have a high dielectric constant, but a low conductivity, and must be white, which can be used as a Reflector. The typical composition of the coating is borosilicate zinc titanium, which may contain a small amount of potassium fluoride and oxides of potassium, barium, and aluminum, but trace amounts of lead, iron, nickel, cobalt and other impurities must be excluded from the coating.

Then the required proportion of phosphor is mixed into another enamel melt and applied to the enameled iron plate to form a coating containing phosphor, which is about half the thickness of the bottom layer. The melting temperature of this enamel melt should be lower than that of the bottom enamel melt. Take it out of the furnace while the enamel on the iron plate is melted but not yet cooled, and spray a layer of tin salt solution to form a transparent conductive tin oxide second electrode. At this time, if it is connected to an appropriate AC power supply, the plate can emit light.

Finally, the board is coated with a protective glaze. This layer should have a lower melting temperature than the previous layers. It must be an insulating layer, at least the outer surface of the lamp must be non-conductive. However, a small piece of transparent conductive film must be left without the protective glaze to serve as an electrical contact point for the lamp. This contact should generally be located where the edge is not obvious or can be shielded by a bracket.

Ceramic EL lamps can be made into various flat shapes, including circular or angular shapes. There may be holes or slits in the board, but these holes must be drilled before the enameling process and should not be drilled after the lamp is made. Since the cost of the luminous board mainly depends on its shape and the number of holes, simple rectangles should be used as much as possible. The maximum standard size of rectangular board luminous lamps can reach 250x200 mm. The luminous surface can extend to about 1 mm from the edge or the edge of the holes and gaps. If some holes or slits are used to assemble fixing bolts, the luminous surface should not be too close to the edge of the hole.

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