Tag Archives: LED

LED Light Guides Equal OLED Performance

The visual impact of OLED panels is hard to resist. Their luminosity is seductively stylish and sleek. Fashion-forward lighting designers prefer the eerily-even silky glow of the OLEDs, even though these are more expensive, have a short lifetime and can be damaged more easily than other light emitting panels. Now GLT or Global Lighting Technologies, with their edge-lit LED-based light guide technology, is about to turn the tables on OLEDs.

The latest product from GLT, a 4×4 inch LED-based light guide, demonstrates this technology specifically. Compared to an OLED panel, the GLT light guide has better durability, higher efficiency, longer life and is cheaper as well.

Applications that would normally use an OLED panel, can easily use the LED-based 4×4 inch square GLT light guide as a more durable and affordable solution. GLT has designed these light guides for use in general lighting applications and they offer diffused light output very similar to that from OLEDs, but at a much lower cost.

Offering enhanced light extraction, the light guide is very thin – only 3.5 mm. The panel itself measures only 2 mm, considerably thinner than products GLT made earlier. When in use, industry standard LEDs will typically light it up from the edges, with only a small frame concealing the LEDs. The current product gives out 250 lumens when fully powered, while the efficiency per watt is over 115 lumens.

GLT produces several types of molded light guides. All the products, including the new 4×4 backlights, are made using an efficient light extraction technology. A high-precision micro-molding process impresses optical features within the light guide. By arranging the features to provide a unique transition area, light spreads uniformly and precisely over each point across the panel. GLT has several standard patterns that they mold into the light guides. They can customize each pattern and meet any application virtually.

GLT develops their light guides in very thin packages and designs mechanical holding features into the backlights. That allows the host application to carry the entire display assembly and if that is not possible, use chip-on-flex or chip-on-glass type of assembly. That helps to reduce the parts count and material and assembly costs.

According to GTL, their light extraction technology delivers better optical performance than that offered by V-groove or stamped, chemical or laser etching and printing processes. Additionally, their process is more repeatable. After having demonstrated their light diffusion technology for a few years, GTL has now incorporated it into some of its high-end lighting products.

With their light diffusion technology, GLT offers a large variety of design options to the luminaire designers. Some of these designs can already be seen in the round 12-inch diameter pendant light. This clever design achieves results remarkably like an OLED. It uses a light guide incorporating LEDs along its inner circumference and they emit light in multiple directions.

Panasonic uses light guides from GLT in commercially available fixtures meant for mounting on ceilings. In the fixture, multiple light guides create discrete distribution patterns. These include spot lighting, downward flood lighting and upward ambient lighting within the room.

Choose the color of your led

To indicate the hue of a specific type of light source, the standard procedure is to measure its color temperature in degrees Kelvin. For example, for suggesting realistic colors of lights in a 3D scene, you can use a Color Temperature chart. Typically, the white balance of a video camera or a film stock is used as the base for relating visible colors. For this, two settings are used most commonly. The first is the indoor color balance, set at 3200K and the other is the daylight color balance, set at 5500K.

Measuring the hue of light as a ‘temperature’ was started by the British Physicist William Kelvin in the late 1800s. When heating a block of carbon, he noticed that it glowed and produced a range of different colors at different temperatures. Beginning from a black cube, it first produced a dim red light, moving to a bright yellow as the temperature increased. Eventually, it glowed with a bright blue-white at the highest temperature.

To honor William Kelvin, the unit of measurements of color temperature is degrees Kelvin, a variation on degrees Centigrade. Unlike the Centigrade scale, which starts at the temperature of freezing water, the Kelvin scale starts at -273 degree Centigrade, also known as ‘absolute zero’. However, when attributing color temperatures to different types of lights, it is usual to correlate them based on visible colors matching a standard black body. Therefore, the stated color temperature is not the actual temperature at which a filament is burning.

Now, an LED, available as a simple chip on board or COB package, can be tuned for its color temperature. The LED manufacturer Everlight has introduced this as the world’s first color-temperature tunable LED.

Immediately following brightness dimming, the next most desirable feature for users of LEDs is to be able to tune the warmth of the light output. For example, some people prefer a ‘warm’ colored light to a ‘cool’ type of illumination. Accordingly, manufacturers generally implement this feature by using multiple LEDs ranging from cool white to warm white, placing them behind a diffuser.

Everlight provides a very compact solution with its CHI3030 27V/29W series. They have packaged the LEDs behind concentric layers of phosphors. This offers different color temperatures of white as setting a precise color-temperature mix is simple now – just light up the required numbers of warn white or cool white LEDs.

Consuming 29W at 27V, the 30x30mm COB CHI3030 from Everlight is the largest such multi-chip solution for a tunable temperature LED. You can select from among different tunable ranges such as 4745-7050K for the KY Cool-White series to the 2500-5700K for the KH Warm-White series. The typical luminous flux output from the LEDs is 2990 lumens for the 5700K cool white and 2760 lumens for the 2700 warm white. Everlight makes similar other series of LEDs with fewer concentric phosphor rings that operate down to 9W.

Everlight expects such color-temperature tunable LEDs to see mainstream use within the next few years. Adding such extra color tuning flexibility allows manufacturers to calibrate their products easily and precisely at low costs.

LED High Bay Lighting Produces 23650 Lumens

Hubbell Lighting, the pioneer in lighting innovation, has recently launched LUNABAY. This is an LED high bay lighting for the company’s high output categories, one that maintains an optimum efficiency of 95 Lumens per watt. The LUNABAY range can generate as high as 23,650 Lumens. Three levels of lighting are available in this range: 23,650 Lumens, 18,000 Lumens and 12,300 Lumens. Another aspect is the lights offer a CRI of 68 and is tagged with Uplight components. The LED high bay lighting ranges from 130W to 260W of total the system wattage. The lighting functions in an ambient environment within a temperature range of -40°C to +40°C. The lighting has an assured life of 50,000 hours at L70.

Lighting public places require specific features. It must cover the entire area uniformly as well as it has to present a pleasant ambiance. At the same time, it must also be safe and affordable. LUNABAY from Hubbell Lighting provides efficient lighting with a low-glare light and high level of durability. The places where this LED High bay lighting could be utilized are quite vast. They include multipurpose rooms in educational institutions, retail stores, gyms, light industrial facilities and all other places where it is essential to light the interior locations in an attractive and effective manner. LUNABAY provides lighting that cannot be matched for efficiency and durability by any other product currently available in the market.

The most important aspect of LUNABAY is its low glare feature of the LED light it produces. This feature is specifically patented and it remains an exclusive domain for Hubbell. Typically, conventional downlights in large areas generate glare and create a cave-like effect. The special optical system used in LUNBAY totally removes this discrepancy. It offers smoothly and evenly distributed light, which is consistent, has a low glare and a high CRI.

Another aspect to be noted is that the two refractors, 22” crystal clear and 23” aluminum possess Uplight components of 10% and 20% respectively. The LUNABAY lighting offers five color temperatures. The chimney part at the top can have a choice of seven colors matching the interiors. Apart from custom colors, users may select colors from white, red, black, forest green, dark bronze and platinum silver. LUNBAY offers multiple options, which includes control over on/off, fusing, wire guard, no light or 50% light output – leading to additional saving of energy. In emergency, LUNABAY is also compatible with 250VA Light Gear Inverters.

Hubbell Lighting is one the leading and largest producers of lighting fixtures in the USA. Their range covers the complete category of indoor and outdoor lighting products catering to residential needs, commercial lighting, institutional requirements and industrial markets. One of the special features of Hubbell Lighting is that the company has been consistent in developing new products in lighting, resulting in energy savings while at the same time remaining affordable to customers. The LUNABAY LED High bay Lighting is their latest product and is the only one to produce up to 23,650 Lumens. This new LED lighting is sure to make a significant positive impact on the market.

Make an inexpensive & simple UV LED Torch

UV LEDFrom our friends at instructables comes an easy project for use with UV LEDS.

To make this simple project, here’s what you’ll need:
2 Ultra Violet LEDS
1 1/4W resistors (the value of the resistor needs to be calculated based on the forward voltage of the LED you use)
1 non-working 9V battery (or a 9V battery clip)
1 new 9V battery
Soldering equipment

The full instructions on the Instructables site will show you how to put everything together. Once assembled, the light snaps on to a working 9V battery to function.

Keep in mind, you don’t have to use UV LEDS for this project – you can use any color. Just adjust the resistor required based on the forward voltage and forward current of the LEDS you choose.

Buying LEDS without specs or you don’t remember the specs of the ones you have sitting around? Assume a max of 2.8V – 3V and 20mA. I would think high intensity white LEDS would work really well for this project.

I haven’t put this one together myself yet, but I think a few of these are coming with me on my next camping trip. Nice way to light up the tent and the ‘facilities’ late at night. Fun project – and you probably already have everything you need right on hand.