Filament LED bulbs

LED filament bulbs look like traditional incandescent lamps but save on energy costs and have a much longer lifespan. LED manufacturers are designing new products based on LED filament technology to recreate incandescent lighting in every way possible. The classic bulb shapes are designed for timeless, decorative appeal. But it’s what’s inside that makes them so different.

Leading company's including PHILIPS, INTEGRAL and VTAC are giving LED energy-saving technology a new twist by arranging the LED to mimic incandescent. This enables the user much more flexibility to create the perfect warm ambiance without high energy bills.

Filament bulbs are perfect for a wide range of applications including: living  rooms, vintage ambiance for shops & restaurants,  bars and hotel rooms, museums and coffee shop.

Background to filament bulbs
Ushio Lighting introduced the first filament led bulbs in 2008 with the initial goal to maintain the look of the classic Edison light bulb.  Unfortunately, the product did not gain widespread market acceptance due to poor thermal dissipation and incomplete flux geometry. 

The original Ushio filament lamps, have encouraged manufacturers to design many novel and effective design elements which make them superior to first generation LED lamps.  A LED “Filament” typically consists of multiple  LED chips mounted on a transparent substrate instead of metal substrate.  This is common term for this method of LED mounting  is Chip-On-Glass (COG). The substrates are transparent and are commonly made from glass or sapphire materials.  This transparency allows the emitted light to disperse evenly and uniformly without any interference which enhances the flux geometry of the lamp.  

The LED filament is then encapsulated in a resin made up of a silicone and phosphor mixture that performs the usual transformation of the LED chips’ blue light into white light.  This innovative design allows the use both of both blue LEDs as well as red LEDs to modulate the color temperature.  Although the majority of manufacturers rely on the phosphor coating to set the color temperature. The phosphor coating is critical to the Colour Rendering Index (CRI) performance and the safety of the LED filament lamps.   Improper coating of the phosphor can induce leakage of the blue LED light, which can be harmful to the retina as some reports have suggested.