Abstract: An electroluminescent (EL) device achieves a significant increase in the lifetime of EL light sources by using a driver with a controlled duration of intervals between rectangular pulses and between packets is variable, causing changes in the duty cycle, and is determined by a signal passing through a feedback circuit having the EL light source connected to a feedback device including a sensing a resistor, and a programmable pattern generator, which may include a microcontroller, fed by the output of the feedback device. The use of the programmable pattern generator allows for precise control over the required waveform; adjustment of the waveform per a specific EL device to maximize its lifetime; storage of profiles of known EL devices, taking into account their behavior/performance under standard conditions of input voltage; and precise control over not-to-exceed parameters, such as maximum output voltage, current, and overall dissipated power.

Abstract: An electroluminescent (EL) device achieves a significant increase in the lifetime of EL light sources by using a driver with a controlled duration of intervals between rectangular pulses and between packets is variable, causing changes in the duty cycle, and is determined by a signal passing through a feedback circuit having the EL light source connected to a feedback device including a sensing a resistor, and a programmable pattern generator, which may include a microcontroller, fed by the output of the feedback device. The use of the programmable pattern generator allows for precise control over the required waveform; adjustment of the waveform per a specific EL device to maximize its lifetime; storage of profiles of known EL devices, taking into account their behavior/performance under standard conditions of input voltage; and precise control over not-to-exceed parameters, such as maximum output voltage, current, and overall dissipated power.

Abstract: An electroluminescent (EL) device achieves a significant increase in the lifetime of EL light sources by using a driver having a standard DC-to-AC inverter generating a high-frequency quasi-sinusoidal signal, and a generator of low-frequency rectangular pulses. The inverter and the generator are connected so that the quasi-sinusoidal signal is fed to the EL light source in packets. The duration of a packet is equal to the duration of the rectangular pulse. The duration of the rectangular pulses and of the packets remains constant during the entire operating cycle of the EL light source. The duration of intervals between rectangular pulses and between packets is variable, causing changes in the duty cycle, and is determined by the signal passing through a feedback circuit having an EL light source, a photosensitive element, an amplifier, and an input of the rectangular signal generator.

Abstract: An electroluminescent (EL) device achieves a significant increase in the lifetime of EL light sources by using a driver having a standard DC-to-AC inverter generating a high-frequency quasi-sinusoidal signal, and a generator of low-frequency rectangular pulses. The inverter and the generator are connected so that the quasi-sinusoidal signal is fed to the EL light source in packets. The duration of a packet is equal to the duration of the rectangular pulse. The duration of the rectangular pulses and of the packets remains constant during the entire operating cycle of the EL light source. The duration of intervals between rectangular pulses and between packets is variable, causing changes in the duty cycle, and is determined by the signal passing through a feedback circuit having an EL light source, a photosensitive element, an amplifier, and an input of the rectangular signal generator.

Abstract: A visual display is disclosed which includes a flexible elongated electroluminescent light source, whose emitted light varies in accordance with an electrical signal applied thereto, and is connected to the output of an audio output amplifier. The particular characteristics of the light emitted by the electroluminescent light source, such as color and brightness, will vary in accordance with the frequency and output of the audio signal applied thereto. Hence, the electroluminescent light source will provide a visual display which is instantaneously representative of the output signal of the audio amplifier. The electroluminescent light source may be used to provide a low interference connection between the audio output signal and earphones, such as typically used in a personal audio player.