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A patent for a new light indicator to solve the ghost effect

In the civil and industrial lighting sectors, the general trend is to lower consumption and this goal is generally achieved by replacing incandescent lamps with low consumption lamps, characterized by more efficient use of energy, or with LED lamps that are able to reduce energy consumption even more.

When this replacement is carried out it often occurs, in the event that one of the switches that control the lamp is equipped inside with a light signal, the phenomenon that we identify as "ghost effect": the low consumption lamp or the LED lamp we use to replace the incandescent lamp will start to flash, emitting a faint light when it should remain totally off.

This intermittent light emission varies in frequency and intensity depending on the type of lamp used for the replacement, and it is generally more intense and visible on LED lamps. During this phenomenon, the intermittent light emitted by the lamp is certainly not of an intensity comparable to that emitted by the lamp when it is turned on, but it is however clearly visible: when such lamps are placed for example in a bedroom, the phenomenon described can be decidedly annoying.

The "ghost effect" is currently solvable with different methods that involve more or less significant modification of the present electrical system, which generally requires an external intervention by a professional. Under construction of a new system it is possible to realize it from the beginning so that the ghost effect does not occur, but the plant will be more expensive than a normal electrical system.

For these reasons we have studied an alternative way to solve the problem: replacing the light indicator inside the switch with a LED light signaling device equipped with a combination of components in order to prevent the ghost effect from occurring when it is decided to replace the incandescent lamps with low-consumption lamps or with LED lamps.

This indicator works in the same way with all types of lamps: its replacement is a decidedly simpler operation than any modification to the electrical system. As anticipated above, the ghost effect does not occur with all the lamps, but the use of this indicator allows us to have no problems when selecting the new lamps, as there will be no fears that the lamps will give rise to the ghost effect and are therefore not usable in all applications.

We have defined this new type of luminous signaling device AGH (Anti Ghost Effect) LIGHT INDICATOR and we have studied the combination of components so that they can be adapted to almost all of the luminous indicators of our production.

Below we list the main components that make up the AGH indicator:

  • Led with chip optimized for low absorption operation
  • One or more resistors assembled in series with the LED

Starting from the vision and study of the phenomenon described above, which we have  identified with the ghost effect, the following steps have been taken to develop and improve  the AGH light indicator:

  • Laboratory tests to isolate the ghost effect phenomenon and understand what are the main causes that determine it and the possible solutions to solve it;
  • Study of the combination of components to be used inside the signaling device to solve the problem: the components are adaptable to almost all the signaling models currently present in our range. This translates into a big advantage for the customer (manufacturer or end user) who can replace the signal with the AGH device without having to modify and/or add any component;
  • Reliability test on the final solution. This test consists of a series of tests carried out using an AGH indicator, a standard signaling device and different models of low-consumption and led lamps.

Once all the reliability tests have been completed, the solution has been declared valid for the resolution of the ghost effect phenomenon and in August 2016 the patent application was filed: on February 20,th 2019, has been definitively released to us|

For more information, please do not hesitate to contact us: our technical staff will support you with all the information you may require!

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