January 7, 2018

How do LED filament work?

We launched our filament bulb range a few months ago, so we thought we’d write a post to explain more about these bulbs, what makes them unique and how do LED filament work.


What are LED Filament Bulbs?

Filament LED bulbs usually looks like a traditional glass light bulbs. The yellow strip that provides the light, was created to look like the filament of an incandescent light bulb, hence the term LED filament bulb. The original LED filament bulb was intended to mimic the appearance of the original Edison light bulb, you can see in the image how the two compare.


Since then however, the technology has proved highly popular and has been applied to many other types of LED bulbs.


How Do They Differ From Normal LED’s?

Regular LED bulbs use either a single large LED or several smaller chips arranged on a board or heat sink. As the LED’s are placed on a flat surface these bulbs typically produced only a 180 degree range of light.

The filament bulbs by comparison have the LED’s arranged in rows on small strips.

individual filament led chip

These strips face outward, producing a 360 degree angle of light, the same as the original incandescent bulbs.


When a filament bulb is lit, it looks like the whole yellow strip is lighting up. Yet it’s actually individual LED’s chips that are lighting up: In the image below you can see the individual LED  chips that are placed along the strips. 


How Do LED Filament Bulbs Work?

The LED filament is composed of a metal strip with series of LEDs aligned along it. A transparent substrate, usually made from glass or sapphire materials is used to cover the LED’s. This transparency allows the emitted light to disperse evenly and uniformly without any interference or light loss.

how do led filament works 1

how do led filament works 2

how do led filament works 3

The LED’s on the filament strip actually emit a blue coloured light so an even coating of phosphor in a silicone resin binder material is placed over the glass to convert the blue light generated by the LEDs into a more preferable colour. Different phosphor colours can be used to change the colour of the light. For example, the more yellow the phosphor, the more yellow and warm the light becomes. This is how the the different colour temperatures are created.

The major benefit of this design is the ease with which near full ‘global’ illumination can be obtained from arrays of filaments. Another positive benefit is better heat dissipation over traditional designs, due to the LED’s being more spread out, rather than densely concentrated. This in turn can lead to increased lifespan.

Main Features of Ledlam Filament Range.

360 Degree Beam Angle: The clear glass cover and long LED filament make it possible for this bulb to provide a wide 360 coverage of warm light.

Matching Dimensions: The LED filament bulbs are designed to the same dimensions as traditional filament bulb, so replacing they couldn’t be easier!

LED Efficiency: They may look like retro style filament bulbs but they are packed with the latest LED technology and offer more than 100lm per Watt in energy efficiency.

Standard and Dimmable: Our standard filament range are all flicker free and we also supply select lines in fully dimmable versions so you can turn the brightness down and turn the atmosphere up!

Style and Shapes: the new filament range comes in a wide range of shapes and fittings, so you can find the style that’s right for you. Bulbs are available in: Candle, Bent Candle, Golfball, Standard GLS and Large G95 Globe shapes.

Flame Warm

New Filament LED BulbsIn Addition to our standard Day White and Warm White colour temperatures, our filament range is available in a new temperature that we call ‘flame Warm’.

Our Day White colour temperature is around 4000K, whilst our Warm White is around 2800K. Flame Warm takes the colour temperature even lower at 2200K and produces a very warm light that is similar to that of candle light. This will give your rooms a really cozy and warm atmosphere that is great for relaxing in.

flame warm atmosphere

These are the main things what need to know about led filaments, we hope you found this post useful and informative.

January 7, 2018