In recent years, we have become so focused on reducing our lighting load with the help of the highly effective LEDs, such that quantity has taken center stage over quality. When it comes to street lighting, for instance, the IES recommends five different types of lighting distribution which are designed for different applications.
A “Type 1” light distribution is meant for center mounting on long and narrow streets. “Type 2” is designed for slightly wider streets when mounting units on sidewalk poles. Both of these aforementioned types have a long spacing-to-mounting height ratio.
“Type 3” is typically used for wider streets with shorter spacing than “Type 2” whereas a “Type 4” is even wider and generally mounted along the perimeter of a large area, with the light directed inwards. “Type 5” employs a circular pattern that is well suited for mounting on the center poles of parking areas. These patterns are created in the luminaire by the optical train of a source of light, a uniformly luminous refractor, and a specular internal reflector.
However, for most of our street and area lighting needs today, we commonly employ the “brute force” strategy of fixing a large number of glary and bare LEDs into a luminaire which is shaped like an inverted saucepan. While this provides ample lighting, it fails to take into account brightness control. Likewise, for the lighting of internal offices, we usually see tubular LEDs that are mounted bare or in narrow enclosures without any shielding apparatus to control lamp brightness. As a result, the quality of lighting ends up getting sacrificed in favor of the energy-savings properties that are provided by LEDs.
Thanks to technology, however, we now have exposure to connected lighting and the internet which makes it possible to have luminaires with built-in sensors. These can effectively monitor the ambient condition of space, including, light level, humidity, temperature, noise level, etc. and relay this data to a computerized system which can then optimize lighting to suit the environmental conditions. This however raises concerns on whether sensors can measure light-quality metrics such as glare and who can maintain a lighting unit with multiple sensors that all send data to central command for quantitative adjustments.
The truth of the matter is that this system is not very qualitative since people are very different and not many facilities can afford to have skilled staff to program and manage all these systems. An even bigger concern is whether someday the government will decide to equip these lighting systems with cameras. This is a cause for worry since it would create a scenario that is the exact opposite of human-centric lighting.
In comparison, our European lighting counterparts are increasingly providing individuals with greater personal control over their lighting conditions. The lighting systems that we have today are at an ever-increasing risk of being coopted into computer systems which will position luminaires in a space. These will then be used to collect and convey data for reasons other than providing the comfort and visual performance that we normally associate with the science and art of lighting systems.