US and Chinese patent offices grant IST Ltd's LED downlight patent

Sept. 17, 2014
Integrated System Technologies (IST) Limited, a leading British manufacturer of smart lighting solutions, announced that the United States Patent and Trademark Office and the Chinese Patent Office have granted patents covering high efficiency LED luminaires for downlight applications.

US Patent 8,664,882 and Chinese Patent ZL200980139063, “Collimated Illumination System Using an Extended Apparent Source Size to Provide a High Quality and Efficient Fixture”, describe a downlight illumination system that maintains a high light output ratio greater than 0.75, with an extended apparent source size to provide a near uniform illuminance, correlated colour temperature (CCT) and colour rendering index (CRI) distribution across an illuminated area.

One variant of the LED downlight system incorporates either an AC or DC power source with power factor correction, a light emitting source containing one or more LEDs with appropriate thermal conductivity and dissipation means, a reflector and an electronic driver to control light output characteristics and a mechanical means for securing a position of the illumination system.

A second variant of the patent describes how the LED downlight can be controlled to change the fixture’s intensity, power spectral density, CCT and CRI to easily enable tuneable white and biodynamic lighting applications.

A further claim illustrates how a downlight can incorporate diffusers for improving even illumination and the addition of quantum dot technologies for high CRI applications.

Additional claims cover inventive methods to combine LED downlights with sensors, such as occupancy and ambient light detectors, in order to create smart lighting fixtures to drastically reduce energy consumption.

Other variants of LED downlight are included in the description, but in short there are no limits to the lamp's physical size or dimensions and it is ideally suited for all applications, where high efficiency LED downlight fixtures can be used.

Nina Archenhold, head of Marketing at IST, stated, “IST has always been a leading pioneer of LED lighting technologies. In fact, it was one of the first companies globally to realize the full potential of LEDs for downlight and LED panel applications way back in 1998. Today, the granting of this wide ranging patent seems obvious as LED downlights and LED panels are rapidly penetrating the lighting market. However, when the R&D department started its LED development programme during the late 1990s, very few commercially viable LED products were available; white LEDs were only achieving
20 lm/W and their high costs prohibited exploitation in the general lighting market.”

IST has already integrated many of the patented claims within a highly cost effective range of smart LED downlights, including LED panels enabling CCT tuning from 2700K to 5700K. Matt Fitzpatrick, Sales Director, explains, “IST is actively talking to several global, household names in the lighting industry, who are interested in our extensive IP portfolio and know-how. This downlight patent is one of the lighting industry’s fundamental patents and the senior management team at IST has created a global licensing programme for major lighting manufacturers, who want to deploy smart lighting solutions rapidly. Many of our initial conversations have revolved around licensing this latest patent combined with our Pulse Amplitude Modulation (PAM) patent, to create lighting systems capable of delivering data to mobile devices using Visual Lighting Communications, commonly referred as Li-Fi. The PAM LED driver technique is one of the most common methods for sending data using LEDs and the IST technical team patented this technique back in 2001 for all types of LED applications”.

Dr Archenhold, IST founder and lead technical architect, stated “This patent is a crucial plank of our rapidly expanding IP portfolio and covers the main aspects required to create LED downlights for a variety of office, commercial and healthcare applications, whether using AC or DC LEDs with power electronics. Our main aim 6 or 7 years ago was to develop IP to allow the industry to capitalize on the smart lighting market of the future , which would offer intelligent, high efficiency lighting fixtures with integrated sensors, power electronics and advanced controls. A key innovation of this patent family is the ability to create tunable healthy lighting through precise CCT control between 2200K and 10000K for retail and healthcare applications, which is becoming a highly desirable requirement for many end-user applications”.

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