Although vision is such an inherent part of our everyday lives, it is extremely difficult to describe, quantify and measure scientifically. The human eye responds differently depending on brightness and colour; not all eyes are the same and, even if they were, individual colour memories of familiar objects and each person’s individual tastes and preferences […]
There are numerous cases where generators and UPS systems are installed instead of individual, self-contained emergency luminaires. The argument may be that these generators and UPSs still supply power to the light fixtures during a power failure. However, according to SANS 0114-2, emergency lighting shall not only operate in case of general power failures but […]
Part 2 of this article highlights the use of LEDs in various environments and discusses how to specify appropriate protection under such conditions. Correct product selection is imperative to ensure LED performance and lifetime. In Part 1 of this article, we discussed the importance of proper thermal management, including the various ways to ensure maximum […]
A checklist for lighting professionals to follow as they plan tunnel projects. Tunnel-building has become more popular in recent years as planners have grown more convinced of tunnels’ benefits. Not only does it shorten distances and make it possible to cross mountain ranges and bodies of water, but it also frees up ground area, a […]
Organic light emitting diode (OLED) technology is promising for flat-panel displays, but image quality issues must be resolved for it to be commercially viable. Organic light emitting diodes (OLEDs) are emerging as the next wave of technology in the flat-panel display market. This is exciting because OLED displays promise improved display appearance at lower cost […]
Thermal management compounds can improve bulk thermal conductivity by minimising thermal resistance. According to Forbes, the market for LEDs replacements for halogen, incandescent and fluorescent lighting systems for interior and exterior applications alone is expected to grow into a $70-billion industry by 2020. This growth is attributed to the advantages LEDs offer over traditional lighting […]
This article explores the perception of colour across cultures and highlights the use of colour in corporate branding. Never underestimate the importance of selecting the right colour to represent a brand. Every colour used in branding has a psychological link or message. It is, however, very important to remember that these psychological links can differ […]
This article focuses on establishing the correct lighting design criteria for road and street lighting projects. Defining and evaluating lighting design specifications can be a challenging task but, as many professionals are coming to realise, comparing lighting design proposals from different companies can be even more challenging. Given all the criteria that professionals must take […]
Chromaticity difference is specified for colour uniformity, shift in colour during lifetime and individual colour variation of products, and others. The chromaticity difference of light stimuli, in general, is expressed by the distance in the CIE 1976 uniform chromaticity scale (UCS) diagram (CIE, 2004; ISO/CIE, 2009), known as the CIE (u’,v‘) chromaticity diagram or simply […]
A well-conceived surge protection concept for LED lights should be incorporated at the design stage. In the process of retrofitting streetlights, conventional luminaires are frequently replaced by LEDs. The reasons for this include, for example, energy efficiency, subsidy programmes, removal of certain lamp technologies from the market and the long lifetime of the new LED […]
