lighting geekery: photoacoustic spectroscopy

I’m still amazed that after about 20 years specializing in lighting, I can still learn new things that lighting does.  Today’s crazy new thing: Photoacoustic spectroscopy.  Basically, light has enough energy in it to cause material to vibrate, generating acoustic signals that can be measured. I find this interesting because I’ve felt the affect first hand – holding my hand in the beam of a super powerful, crazy-narrow beam LED fixture (which doesn’t have any IR or UV energy in the beam), you can feel the power of the photons.  Mostly what I felt is probably thermal absorption in my skin, … Continue reading lighting geekery: photoacoustic spectroscopy

Climate-Based Daylight Modeling | All Things Lighting

For hard-core lighting designers: A very detailed description of daylight simulations, from Ian Ashdown, the Chief Scientist from Lighting Analysts, Inc., one of the two industry leaders for lighting simulation software (maker of AGI32, which is popular in the US). Continue reading Climate-Based Daylight Modeling | All Things Lighting

TM-30-15 color measurement standard

The IES has put forth a new color metric standard that is far more comprehensive then the old CRI (Ra) measurement system.  It will take time, but I hope manufacturers and specifiers alike adopt the new system. For a more in depth discussion, check out this Architectural Lighting article. Below is the information from the DOE SSL Postings email: A New Method for Evaluating Color Rendition The Illuminating Engineering Society (IES) has just published an important technical memorandum, TM-30-15, which outlines a new system for evaluating the color rendition of light sources. It was developed by an IES task group that … Continue reading TM-30-15 color measurement standard

nearsightedness and daylight

Interesting article in Treehugger posits that exploding global rates of myopia – nearsightedness – might be caused by children’s lack of exposure to daylight. Here’s the punchline: While some researchers think more data is needed to confirm the theory, animal experiments further support the idea that being outdoors, and exposure to the light that comes with it, is protective. The leading hypothesis, explains Dolgin, is that light stimulates the release of dopamine in the retina, and this neurotransmitter in turn blocks the elongation of the eye during development. Based on epidemiological studies, Ian Morgan, a myopia researcher at the Australian … Continue reading nearsightedness and daylight

U.S. DOE releases new fact sheet on light + health

Check out the new fact sheet published by the DOE.  It helps to clarify and dispel some of the myths surrounding LED lighting and its impacts on health. I think this paragraph is the perfect summary: What may be beneficial for an occupant during the day may be harmful at night, and may vary significantly between indi­viduals in a given space. Complicating things even more is the need to balance the desire for alertness with preservation of normal circadian rhythms among night-shift workers, for exam­ple. Therefore, even if a prescription for effective nonvisual stimulation is developed, implementing the solution may … Continue reading U.S. DOE releases new fact sheet on light + health

edison report: SIL Europe – the paradox of standardization

The folks at the Edison Report Europe have summarized the presentations at last week’s Strategies in Light Europe event in Munich, including a tidy summary of my presentation “The Paradox of Standardization“: Brad Koerner (Philips) gave an overview of the present design practices and tools in architectural lighting. He made a plea to provide information on SSL lamps-luminaires and modules in a way that it can be directly imported in the software tools used by lighting designers and architects. He showed an interesting example of so-called on site manufacturing of luminaires using Zhaga compliant SSL modules where the luminaire was basically … Continue reading edison report: SIL Europe – the paradox of standardization