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I am currently researching Electroluminescent Inverters/Drivers for a project. There is many accounts that EL Wire needs a higher voltage and frequency than an EL panel or tape needs. (300vpp vs 150vpp, 2000hz vs 400hz, typical/average numbers). Considering that phosphor is phosphor, and two capacitors of the same arbitrary value should act the same, why is this? Why would 1 square inch of EL Wire differ from 1 square inch of EL panel/tape?

I do understand that a higher voltage can drive a larger run and a higher frequency can make it brighter, but all things considered equal, why would the form factor of the two matter?

As Electroluminescent displays are essentially capacitors, I don't understand how the different frequencies matter.

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While EL wire tends to use phosphors, the EL displays that I am aware of typically use materials like GaAs. Phosphors use ballistic transport and electron impact to impart the energy where as the semiconductor type devices have recombination of electrons and holes.

The semiconductor type panels will be more efficient (generation is less energetic) less scattering and reduction of energy before the light is emitted.

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The frequency can actually change the apparent brightness from the EL material. The higher the frequency, the "brighter" the light. The old "night-light" EL panels were very dim operating at line voltage and frequency. So in the US (120v/60hz) you had a panel with no active components that provided a dim light. If you hook one of these up to a frequency generator with a line voltage capable transistor for drive, you can brighten the panel by raising the frequency at the cost of longevity. The voltage requirements are for light generation itself. It is the field that produces the light, not heat. The electric field causes the luminescence of the phosphor like an invisible electron beam hitting phosphor on an analog oscilloscope screen.

The reason for using AC is because the charge will flow from "plate" to "plate" through the phosphor causing the phosphor to emit light each time the field flows through it. The faster that happens, the more excited the molecules in the phosphor becomes..increasing the brightness.

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