LED lighting - was that it?

So far, solid state lighting has been about replacing conventional light sources with LED technology. Today, in most cases this task has been accomplished. Major luminaire manufacturers like Philips, Osram, Zumtobel are at 70% LED share of revenues or above. Smaller ones have already reached 100% several years ago. The driving force behind this is efficiency combined with solution cost. Realistic payback times of only a few years or even less can be achieved: LED lighting pays for itself in most cases! A lot of progress has also been made reaching the same light quality as we were used to before with halogen bulbs or metal halogenide sources.

Mission accomplished! Or not?

Well, not everything is done yet. The luminaires are still the same, maybe flatter. Was that all LEDs could do for the lighting industry?

No, of course not, you will say. Now it is argued that LED, albeit "digital" lighting, enables an unprecedented control of the light flux, color (temperature), and distribution. Plus, whereever there is light, there is electricity, and environmental factors which can be picked up, analyzed, interpreted, and used to control the light itself and other building functions. How come the industry realizes this potential only now? Think about it, we at cenogent have our own opinion.

We are convinced that sensors, intelligence, IoT, LiFi, are all important and will find their place.

But this is not what lighting is all about. Lighting is about light. Lighting is about providing the right quantity in the right quality at the right location at the right time. Let's look at these criteria in more detail:

• quantity: depends on the task, the location, the time of the day, the persons. The right balance is important.
• quality: it's not only CRI (or CQS, IES TM-30, TCLI, ...). It is also about directionality, diffuse or direct, shadows, contours, textures - surfaces. Light is visible on surfaces only!
• location: we do not feel well in uniformly lit environments. Those appear dull, without depth of field, lack of details, low resolution. Distribution of light is critical.
• time: at different times of the day, different light is required. Time is also timing. Imagine a theater spot at the right position but the wrong time.

In following contributions, we will look at some applications and examine them using the criteria above.

© cenogent, 18.11.2017