Semiconductor Traffic Light Sources


The Product


Precise name of the Product: Semiconductor Traffic Light Source. It is produced from light emitting diodes (LEDs).

Great amounts of different signals are used in the industry, the transportation and even at our homes. These vary in size, brightness, colour and quality.

An intense standardization has been developed mainly because of the legal and safety requirements of transportation, which is used almost worldwide under international conventions, by reason of the CIE (Comission International d’Eclairage) recommendations.

In signals, having their own light, colour light can be generated by three different sources:


The following Table contains the comparison of different light sources



Light bulb and filter

Fluorescent lamp




Extremely bad

(less than 1,000 hours in flashing mode)


(approx. 8,000 hours)


(more than 20,000 hours)


Severely worsens as getting older








Regular change of bulbs



Shake proof







(Slowly increasing)

About two times higher than a light bulb


About two times higher than a light bulb


Cost of Operation





*Data from 1998. Efficiency of new LEDs are improved by 25% every year.


The Table above refers to the most frequent light-sources with low and medium luminous output (0.1-20 lumen). Much higher outputs can not be economically generated by LEDs, 500 lumen or higher luminous outputs will be chiefly generated by light bulbs in the next few years.

For the most part traffic lights are used on public roads and in railway safety devices.

Our product is a traffic light source for the railway and public road traffic control systems. It is officially licensed by the adequate Hungarian authorities. Official permission for application of light sources of railroad crossing lights (concerning regulation is equivalent to the regulation of public traffic control systems) was given in 1994, and for light sources of railway signal lights in 2000.

Signals having their own lights (our product is included) have the following groups of colour: red, yellow (amber), bluish-green (green), blue and moon white. These are well defined, measurable qualities that are measured by the adequate qualifying institutes.

Our product has been available in every colour since 1999.

For a more simple usage hereinafter the semiconductor traffic light source will be called LED light source.

Lights used in traffic management and railroad crossing signals are under the regulations of MSZ (Hungarian Standard) #20186-86. These regulations meet the requirements of international recommendations and order five main optical parameters.

Currently, in Hungary the only product that meets all the regulations is the LED light source (trade-name ’LSzR’) produced by the Percept Ltd.


Everyone must have experienced the negative phenomenon when, even in the morning or afternoon sunshine, traffic lights can not be seen. Technically speaking it is called ’phantom light’, that originates from the structure of the light source and can hardly be eliminated.

LED light sources have hardly any ’phantom lights’, that is why even horizontal sunshine can not deteriorate the visibility of this kind of signal.


It is not only proven by the measurements of the Hungarian Electrotechnical Qualifying Institute but by the fact, that (as far as we know) in the five-year period of 1996-2001 there were no accidents at more than seventy railroad crossings installed with LED light sources.

 Comparing the statistics of the two railroad crossings, where LED light sources have been installed for the longest period of time, with the former statistics it is proven that three human lives were saved and millions of HUF damage were prevented so far, due to the excellent visibility.





Chiefly in railway safety devices

Currently our main and permanent business partner is the MÁV (Hungarian Railway Company) that operates 32,000 railroad crossing traffic lights and approximately 180,000 railway signal lights (semaphores). Replacing the former light sources is limited only by financial resources, as technical, safety and operating disposition towards LED light sources is remarkably supported.

In traffic lights



 Production Capacity

 Regarding the type ’LSzR-150-xx’ Ø 150 mm our production capacity is 1,800-2,000 pieces per year at the moment, that can be raised to 9,000-10,000 pieces per year at the same factory.