Quanta LEDs with a twist of decor
In our review about the Quanta 18 LED from Eternaleds, I talked about a little trick to improve the light distribution and dispersion. LEDs are not especially good at being a general room light, as they tend to be directional and produce harsh shadows. The Quanta range from Eternaleds are designed to be floodlight replacements, that is, they are partially directional to produce a soft cone of light in one area.
My modification was to fit a simple paper lampshade around the LED that assists in difusing the light and making it suitable for a general room light.
From floodlight to general room light
Fitting a simple paper lamp shade to cover the LED provides an easy solution that has the following effects to facilitate general room lighting:
- Softens the white light by adding a warming effect through the paper medium
- Scatters the light, to provide a more even distribution around the room
- Can provide a ‘Mood effect’ if you use a coloured or art-paper shade
- Reduces glare and the beam effect that causes strong shadowing
- Covers the direct view of the LED(s) thus preventing eye ‘blind spots’
- Provides a totally safe modification, due to the low LED temperature.
- Allows a little stylising by matching a lampshade shade to the decor.
Let’s look at a conventional light bulb for a moment.
Electric lamps with a clear glass envelope emit light where you can easily see the light source filament. This can be quite harsh when viewed directly. The common way to relieve this is to create translucent diffuser envelope. The usual method to achieve this is to break up a light source by sandblasting the inside of the lamp envelope, etching the lamp envelope or coating the lamp envelope. This depolishing process has the effect of scattering the emitted light and diffusing the intense light source of the arc, or filament. Acid etching or coating the lamp envelope is most commonly found in a conventional household type of incandescent lamp, wherein the glass envelope enclosing the filament is acid etched (frosted) and/or coated inside with a particulate, light-diffusing powder. A mixture of clay and silica is generally used as a light-scattering powder, because of its availability, light-scattering properties, chemical inertness, low cost and ability to withstand the high temperatures reached during lamp operation. Conventional light bulbs can also be obtained with tinted glass envelopes that modify the light colour, to provide greater ambiance.
An LED with diffuser envelope?
An LED emitter generally runs at a much cooler temperature than a filament bulb and I see no reason why they can’t be enclosed in a similar depolished and coloured envelope. To date, I have not seen these in production, though no doubt with the SSC Acriche LED, it won’t be long before we see a retrofit replacement looking identical to an old style light bulb, but with a LED inside it! This method of construction will compliment the efforts to improve the aethestics of CRI as well as light distributions. Until that appears, we will need to make the light scattering through other mediums such as the paper shade.
Making a home made LED diffuser
Utilising this principle of defusing light, I tested a warm light 9 Watt model of the Eternaleds Quanta range, by fitting it directly into a paper globe lampshade. The whole assembly was fitted in a center room ceiling fitting with the LED pointing downwards. These shades are easily available in the UK, I bought mine from Dunelm for £1.99 They are also available using coloured paper and in different shapes. Maybe not everyones taste in lampshades, but very effective as a light diffuser. You may find other types of lampshade that work just as well or better. The main criteria is using a shade that exposes as little of the LED as possible, provides minimal light blocking through the shade medium and scatters the light evenly.
How did it look?
I was very pleased with the light distribution and I found many other changes that I listed above, making this a good modification to achieve a general room light.
The floodlight effect is completely removed by the shade and the omnidirectional effect is clearly seen. The light is simply bouncing around inside the spere shade before exiting omnidirectionally. The paper has the added effect of scattering the light through the fibers, thus reducing shadowing and harshness.
Some mood lighting?
Taking this idea one step further, I installed a Daylight White 9 watt Quanta LED inside a pebble drop blue lampshade, also from Denelm. The assembly was again placed in a downward vertical ceiling centre light fitting, where the room had been decorated in a blue theme. This worked very well as the neutral white LED light complemented the blue tints of the decoration.
There are some ideas to experiment with as you wish. Please comment here is you have any questions or ideas to add. In my next article,
For more information and to purchase the Quanta range of LEDs please visit Eternaleds
Coming soon …
I’m taking this concept a step further by making a complete DIY LED for general room lighting using these principles.