On this year’s prolight+sound in Frankfurt a new LED technology for the entertainment industry was introduced. The new technology goes by the name of Chip On Board (COB) and it will probably become the future of high-power LEDs. The German company Steinigke Showtechnic added numerous COB products to their assortment. As kind of midwife we asked Matthias Schwab of Steinigke some questions about this exciting technology.
ZioGiorgio.com: Can you describe this new technology?
Matthias Schwab: To describe the COB LED technology, one should take a brief look at LED history. The classic LED is one with wire leads in a cylindrical reflector package – the form reminds of a thimble. One LED, one color – with or without heat dissipation.
The second type are SMD LEDs (Surface-Mounted Device). These LEDs don’t show wire connections. They are directly soldered on a printed circuit board.
The latest generation of high-power LEDs is characterized by COB (Chip On Board) manufacturing. Numerous tiny semiconductor chips (LEDs) are mounted on a flat circuit board. Common LEDs are spread all over the respective device – this chips are very small and placed in the center of the spot.
ZioGiorgio.com: And what is so special about this?
Matthias Schwab: The benefits! The secrets lies in the closeness of the single LED elements. This evokes the impression of one common light source. It just doesn’t look like several LEDs, but like one illuminant – just as a conventional source. So, no more color shades or single color dots.
ZioGiorgio.com: Apropos colors – have color illustrations been improved as well?
Matthias Schwab: Indeed. LED colors have never been so homogenous, so deep. Intermediate colors can be displayed better as well. Proper illustrations of colors like purple, for example, have been restricted to conventional spots with color foils or dichro filters. Even tricolor or quadcolor LEDs have not been able to produce a really competitive intermediate color – now COB modules do.
ZioGiorgio.com: What about the power?
Matthias Schwab: Also an immense advantage. COB manufactured light sources offer 100 lumens per watt or more. We offer devices with 100 watts per chip. This means we can by now easily replace conventional devices with up to 1 kW!
In the moment we deliver classic spots with ML and PAR housings or audience blinders. In the field of profile spots or studio lights we offer alternatives with COB for conventional light with up to 500 watts. It is part of our mission to not only produce the required light power, but to also stick to well known housing sizes. And, as already shown with the ML and PAR housings, it is our aim to do without fans, although COB modules with 100 watts are used.
ZioGiorgio.com: No disadvantages at all?
Matthias Schwab: One thing which has to be improved for some applications is the beam angle. The COB modules deliver a wide and even light space. About 30° beam angle is the minimum at this stage. But we are already working on solutions to control the light output.
ZioGiorgio.com: Who has developed this technology?
Matthias Schwab: The assembly method stems from the chip technology. Texas Instruments was probably the first to use it in large series. The LEDs that were necessary for the COB manufacturing were originally developed by Nichia Japan. But as there is no patent on the whole COB-LED technology process, it is quite difficult to really define who was the first to put all small steps together.
By the way, two or three years ago, COB modules have already been available in street lamps or some outdoor spots. But we have been the first to fully present them within the entertainment industry.
ZioGiorgio.com: Like other LED technology, is this one green as well?
Matthias Schwab: Compared to any conventional illuminant LEDs are always green. The power consumption of classic LEDs is a bit lower than the one of COB modules. But as already mentioned, far below the common sources. Considering the lifetime, COB manufactured devices outdo the “old” light sources by far.
Something about the lifetime in general. With the presentation of the first and second generation of single LED spots came an euphoria as lifetime was pushed to 100,000 hours. Thanks to the great experience we can classify the current lifetime specification as more reliable – still it should not be forgotten that conditions (temperature, humidity, cycles of operations and the like) to define the data are perfect. COB lights with up to 100 watts easily perform 12,000 – 14,000 hours these days.
ZioGiorgio.com: Can any desk/controller be used or do they need a specific controller?
Matthias Schwab: Yes, any DMX controller can be used. By the way, COB modules don’t require more DMX channels than other LEDs – it simply depends on the composition of the modules. Those with RGB require more, of course.
ZioGiorgio.com:Do you have plans for a moving head range?
Matthias Schwab: We already have some moving heads with COB element, like the new Futurelight DMB-60 or the DMH-90. We will definitely continue to use COB modules in future moving heads.
ZioGiorgio.com: How will the future of LEDs look like?
Matthias Schwab: As is true for almost every technology, considering the development there is no end in sight. A limiting factor at this stage are cooling systems and the housing sizes. We will see what the future brings, but looking back 10 years ago, it is absolutely amazing what has been achieved from the first single and weak LEDs to the COB LED technology.
Jay Green – Alex Panella
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