Partial flux – measurement reliability of lensed LEDs

  Most LED manufacturers use units of luminous intensity (cd) for the measurement and classification of LED brightness. This procedure is reliable and reproducible for numerous LED types, but is insufficient for LEDs with narrow emission angle characteristics. This article describes the procedures for measuring luminous intensity, partial flux and luminous flux, along with the […]

LED: what the end-user should know

  It is expected that LED lighting will account for more than half the global lighting market by 2017, making it essential for the end-user to better understand this technology. Although the cost of LED products is currently higher than regular lighting systems, the demand for LED technology is growing exponentially, which will inevitably result […]

Farewell to the incandescent lamp

  This article discusses the place of the incandescent lamp in the lighting industry over the years and explains in some detail three alternatives to this technology offered by the lighting industry. A lot has been written about the invention of the incandescent lamp. The first attempts at creating light using incandescent technology were made […]

The challenges of dimming LED loads with magnetic transformers

  The technical difficulties with dimming low-voltage LED lamps on magnetic transformers and some design tips to improve the situation and avoid problems. Anyone who has used LED loads with low-voltage magnetic or electronic transformers in dimming applications has likely experienced confusion, frustration or disappointment. Some blame the dimmer as the cause of the problem, […]

Thermal measurement guidelines for LEDs

  Guidelines for the thermocouple attach to measure the solder point temperature and the calculation of the approximate LED junction temperature for various LEDs. One of the most critical design parameters in an LED illumination system is its ability to draw heat away from the LED package. High operating temperatures at the LED junction affect […]

Light pollution in South Africa: 2011 versus 2001

  This article outlines how artificial skyglow, also known as light pollution, is modelled using Census 2001 and Census 2011 population data. Light pollution is defined as “any adverse effect of artificial light including skyglow, glare, light trespass, light clutter, decreased visibility at night, and energy waste” [1]. This work, illustrated here, is a follow-up […]

Fundamentals of lighting design

  A basic guide to lighting and lighting design explaining variables such as working plane, mounting height; depreciation factors; coefficient of utilisation and reflectance factors. The following basic design concepts should generally be considered when designing a lighting solution for either indoor or outdoor applications: Whether the lighting will be installed in a safe or […]