A Bright Redesign for LED Lights

Illumitex’s new optical design makes LEDs brighter and more energy efficient. by Erika Jonietz

Illumitex, an LED-manufacturing company based in Austin, TX, launched its first product line earlier this month. The startup’s first LEDs are designed for general-purpose lighting and emit a uniform, narrow beam of white light that is almost two times brighter than any white LED on the market. The founders, all of whom have backgrounds in optics rather than solid-state lighting, achieved this by redesigning the package around the semiconductor chip that actually converts electricity into light.

Traditionally, LED manufacturers have enclosed the chips inside a dome in order to control the light output. Illumitex’s LEDs ship in a flat, square package that eliminates the cost and energy efficiency issues that come from using secondary optical lenses and reflectors. Cofounder and chief scientist Dung Tien Duong, who is the company’s primary inventor, won’t say much about how the unique package allows Illumitex engineers to extract more light from the LED dies, but he does say it takes “intuitive” advantage of physics principles. “If the chip is square, the light beam should be square,” he says. While the company is mum on the exact physics behind its achievements (patents are still pending), it has published data sheets for both its 16-die and 4-die LEDs, including some data verified by third-party testing companies.

Illumitex’s LEDs have a unique flat, square package that allows engineers to extract more light from the semiconductor chips at the heart of the diodes. (c) Illumitex

Illumitex sells its packaged LEDs to companies that make LED-based light bulbs. CEO Matt Thomas says the startup already has several customers that sell products for outdoor lighting (e.g., streetlights) and commercial “high-bay” lighting (typical in warehouses or convention centers), as well as one company working on an LED replacement for the fluorescent tube lights usually found in offices. Only one customer is public at this time, Singapore-based LED Works,  which has designed lighting for several famous casinos and hotels worldwide, as well as for the Singapore Flyer, the world’s largest Ferris wheel. Thomas says LEDWorks is incorporating the Illumitex LEDs into “a PAR30 replacement,” referring to the most popular floodlight-style bulbs used in indoor lighting, that could deliver 500 lumens for only 7 watts. A commercially available compact-fluorescent PAR30 bulb typically puts out 750 lumens of light at around 16 watts, while a halogen version might deliver 600 lumens for 50 watts of power.

Thomas says that in addition to their brightness and energy efficiency, Illumitex LEDs offer one advantage completely unique to its package design: the beam angle–that is, the angle at which light emerges from the package–can be tailored from 10° to 90° with limited light loss. This allows manufacturers to design systems that provide consistent, directed lighting without the dark spots or “spillover” typical of most lighting systems. For instance, picture a typical block of street lights: there are alternating bright and dark patches, and perhaps 25 percent or more the light “spills over” into the windows of homes and stores along the street. Although LEDs allow designers to direct the light, conventional domed LEDs still end up wasting a fair amount of energy on spillover. In contrast, Illumitex has created computer models that show its LEDs can be used to design a system that would provide consistent illumination along the sidewalk and street with only minimal spillover.

A 16-die LED illuminated in one of Illumitex’s onsite testing labs. (c) Credit Technology Review

The company has pilot manufacturing facilities and extensive R&D and testing equipment in its south Austin office space. Full-scale manufacturing, however, is done in Asia. Though the actual LEDs in Illumitex’s first chips are “industry standard for white LEDs,” says Thomas, the company is extending its research beyond packaging and into actual LED design in its efforts to continue improving the efficiency of LEDs for general lighting.



On AppleInsider: A new Apple patent application revealed this week describes technology that would allow an external light source, like the sun, to provide the backlight for a display, helping to conserve battery life.

The application revealed this week, entitled “External Light Illumination of Display Screens,” notes that current LCD displays can be difficult to view when outdoors in direct sunlight. In addition, it said, it often takes high-powered components to properly light the display. The patent describes a way for a portable computer, like a MacBook, to collect external light to illuminate the computer screen.

One described method would employ a “light harness,” which would serve as a collector of light that would then be displayed onto the screen. This could be done by having the harness reflect light toward the back of the display panel.

In addition to the sun, external light could come from a variety of sources, including an accessory light bulb that could be a part of the mobile computer. The application also mentions such a device could be used in a vehicle, with the screen illuminated by a light inside a car.

The system could also include internal LED light sources that could be used in conjunction with the external light source, if there is not enough light available to properly see the screen.

“The internal light sources may also increase the power consumption of the electronic device,” the application reads. “Therefore, a manifold or other light harness may be used along one or more edges of the display screen in conjunction with or as an alternative to the internal light sources to provide illumination to the display screen by emitting light channeled from an external light source across the display screen.”

Patent 1

One potential method would have the reflector behind the display screen, relaying light to the back of the panel to illuminate it for the user. Another method described in the application would allow the user to remove the reflector entirely, if the user were to position themselves and the back of the computer display towards the light source.

Patent 2

The technology would rely on a translucent surface, either removable or permanent, placed behind the computer display. The surface would either pass or harness external light, allowing the display to be illuminated. The surface could also be hardened to prevent damage to the display.

Patent 3

1. Patent # 7677770 for an apparatus for retrofitting LED-based recessed lamps into incandescent or fluorescent recessed lighting fixtures.

An LED down light replacement apparatus is disclosed for insertion into a recessed-light housing can, which includes an LED light source, a means for mounting said LED light source within the housing can, an LED driver circuit electrically connected to the LED light source, a heat sink in thermal contact with the LED light source, and means for removing heat generated by the LED light source. The means for removing heat generated by the LED light source can include a fan and/or ventilation holes in the top of the housing can.

There are many types of lighting fixtures for the home or office which are known in the art. These include Edison based fixtures, surface mounted fixtures, track-lighting fixtures, and recessed fixtures. These fixtures have traditionally come in three types: incandescent, fluorescent, and high intensity discharge (HID) lights. All three suffer from inefficiency, relatively short life, and high heat dissipation. For example, incandescent lamps produce in the area of 14 to 17 lumens per watt. In addition, incandescent light sources use a thin filament which glows when heated by electrical power and tends to burn out easily. Typical, incandescent lamps have to be replaced every 2000 hours. Fluorescent lamps are an improvement over incandescent lamps, producing 50 to 120 lumens per watt, and lasting about 15,000 hours. HID lamps last about 20,000 hours.

To overcome inefficiency and to extend lifetime, LED-based lighting fixtures have been introduced. A white light can be produced by combining a blue led with a phosphor, or by combining red, green, and blue LEDs. These combination LEDs can be formed into incandescent-like bulbs and recessed cylindrical or rectangular fixtures. In order to avoid replacing the large base of existing incandescent-based recessed lights, LED light fixtures can be designed to be retrofitted into existing fluorescent rectangular or cylindrical “can” incandescent or fluorescent fixtures. The LED recessed lamps in the prior art, however, operate generally at low wattages, typically about three watts. If the wattage is raised to increase brightness, say to about 5-50 watts, the increased heat dissipation causes the LEDs to drift out of current-voltage specification, thereby introducing unwanted color variations and even failure. In some circumstances, depending on the thermal environment of an LED recessed lamp, ventilation may be needed for power dissipation as low as 2 watts (or a light output of about 100 lumens or more).

As such, there is a need in the art for an improved retrofittable LED-based recessed light that can operate at relatively high wattages without incurring color variations or risking failure at high output power.

The above-described problems are addressed and a technical solution is achieved in the art by an LED down light replacement apparatus for insertion into a recessed-light housing can, which includes an LED light source, a means for mounting the LED light source within the housing can, an LED driver circuit electrically connected to the LED light source, and means for removing heat generated by the LED light source. In some embodiments, the recessed-light housing can is part of the apparatus; in other embodiments, the apparatus is inserted into an existing housing can after removing an existing incandescent or fluorescent light assembly.

The means for removing heat generated by the LED light source can include a heat sink in thermal contact with the LED light source, and a fan and/or ventilation holes in the top of the housing can. When the apparatus includes a fan, the fan can be mounted on the heat sink or on a top surface of the housing can. The apparatus can include a trim and a ventilation cone with a conical flange protruding therefrom. Air is drawn in through the heat sink by the fan and directed between the fan and the housing can out through a space between the trim or housing can and the truncated conical flange of the ventilation cone.

Light has the power to do much more than just illuminate our environment.  Light can heal and affect moods and reverse aging of our skin.  The multi-colored LED lights that Eaglelight sells may not only brighten your moods, they also may make you healthier.

Light therapy is an approved way to cure “SAD”, Seasonal Affective Disorder,  also known as winter depression. “Blue-light” therapy is a cure for jaundice in very young babies and violet lights kill the bacteria that causes acne. Light therapy is also reported to help with Parkinson’s tremors, improve mental disorders, regulate sleep, and promote the healing of wounds. These are just a few of the benefits you can get from using LED lights.

Colored light therapy has been around for a long time. The ancient Egyptians installed panes of colored glass in the ceilings to color the light that entered for healing effects. In traditional Chinese medicine, each organ is associated with a color and the practice of qijong uses color for healing. Indian Ayurvedic medicine uses all colors of the spectrum to restore harmony and health.

I will research and write more about health and LED lights and share with you what I learn.

I’ve been saying for some time (as have others) that the Pharox LED replacement bulb is among my favorite LED bulbs.  One reason is the quality of the light – the LED bulb has a frosted globe that diffuses the light and the Pharox gives off a nice, soft, warm glow, much like the old incandescents.

I’m also thrilled that Lumnis Lighting, which makes the Pharox, has now developed a more powerful Pharox II bulb that will substitute for the 60 watt incandescents as well as the Pharox I bulbs have done for 40 watt bulbs.

LEDinsider sells the Pharox I and will carry this new Pharox as soon as it is available.  UPDATE: EAGLELIGHT.COM SELLS ALL PHAROX BULBS, INCLUDING THE NEW DIMMABLE  LEDs.

Dutch news just announced that 2.4 MILLION Pharox bulbs will be distributed to lottery participants.

The National Postcode Lottery and the World Wide Fund for Nature have announced that they will distribute 2.5 million Pharox bulbs to lottery participants. The Pharox, which is a new LED bulb which emits a soft white light, was developed by two great-grandsons of the founder of the Dutch electronics firm Philips. It uses only ten percent as much energy as a conventional lightbulb and can burn for up to 35 years. When he visited the Netherlands last year former US president Bill Clinton promised he would promote the new bulb worldwide.

ECOlight Water Powered Shower Light

Sylvania brings you an eco-friendly showerhead with this new ECOlight Water Powered Shower Light. This easy-to-install showerhead features bright and functional LED light as well as a smart water temperature indicator ring. Red means the water is hot and blue indicates when the water is cold. The light is powered by the flow of water, so this is a very energy-efficient invention. Priced at $39.99 at Gizmo.

Dialight has introduced a new ETL-recognized version of its ultra high brightness Powerwhite® LV Linear Modules. The company says it is the first complete LED solution product of its type on the market and it will enable the rapid development of many LED lighting applications including existing fixture formats and entirely new product designs.

Dialight’s Powerwhite system comprises two elements – modules and drivers – as well as an option to have both elements integrated into a single product. The technology it delivers is ideal for the design of new LED lighting fixtures for linear, accent and flood lighting, signage, street and area lighting as well as general illumination. In many cases it can also be successfully integrated into existing fixture designs, converting them into next generation lighting solutions with the advantages of LED technology.

Measuring 297.18×38.05×14.86mm each Powerwhite module contains six of the latest LUXEON® Rebel™ LEDs complete with compact collimating optics. Color binned for consistent color, the LEDs are available with 80+ lumen for cool white, 70+ for neutral white and 50+ for warm white. The housing combines a die-cast heat-transfer base and plastic front cover to create a module with no interconnecting wires or visible solder joints. They are also available with an on-board driver allowing them to be driven by a 24V supply for even simpler installation configurations.

The Powerwhite driver is capable of driving up to 48 LEDs or 8 modules in a series chain at 350mA and 24 LEDs or 4 modules at 700mA. To aid installation it is capable of operating in ambient temperatures of up to 80ºC. This allows integration within the fixture alongside LED modules resulting in fixtures that can be installed using traditional techniques. The driver also features a thermal-feedback circuit which can monitor the operating temperatures of the driver and the LED modules to ensure the protection of the whole system.

In addition, Dialight’s Powerwhite modules have been designed to handle higher voltage levels, enabling manufacturers to comply with the requirements of EN60598 and UL 1598.

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