Over summer I decided to build a LED light for my bedroom but I wanted it to be better than normal white LED's so I decided to create an rgba (red, amber, green and blue) light.
I decided to go with rgba insted of rgb because it has a higher cri and boosts the amount of light in the red end of the spectrum, allowing you to increase the amount of green and blue to make it white again therefore increasing the brightness🙂
I got the idea and dimming circuits from Dan's great Instructable found here.
My light edmits a calculated 2400 lumens of white light at 70watt (includes diffuser loss), this makes it a lot brighter and about three times more efficiant than my old halogen light (4x40w)
The LED's are Luxeon Rebels I have used two strings of red (14 led's or 7 per string) each at 350ma (700ma in total), 6 PC Ambers at 700ma, 6 Greens at 1A and 6 Royal blues at 1A. All the LED's were the highest lumen bin avaliable.
The total cost was about £255 or about $407 at the current exchange rate.
As you can see I have used a large heatsink and a quiet pc fan (Noctua NF-P12)to keep it cool 😎 and I have used a frosted piece of perspex as a diffuser.
The LED's were soldered onto an mcpcb then bolted using nylon bolts onto the heatsink with thermal paste for excelent heat transfer. in the photo only the red and green LED's are on also you can see the thermistor in the centre.
The controller is compleatly analogue as and each colour is compleatly adjustable. The sliders are for the main ajustment and the dials are for precise colour adjustment. The small LED's tell you when it is on, when the fan is on and when it has overheated and turned off.
These pics shows the placement of LED's
This shows the inside of the control box showing the power suply and circuits.
Beam shot photos taken with my 3 megapixel phone set to daylight.
Incandesent light
rgba set at a warm white
rgba set at a neutral white
rgb, note the oranges look redder
The circuit diagram for those who are interested. I set the fan to come on at around 40 centigrade and the overheat shutdown at around 50 centigrade these figures are lower than the original (60 and 80) because the fan, once it turned on, slowed to an compleatly inaudiable crawl so I lowered the temperature to increase its lifetime and efficiancy.
The wavelengths from luxeon datasheet, since the amber is a blue LED with a phospher (4 times more efficiant than normal ambers) it has a wider spectrum so it is more of a warm white/amber led. (I drew the amber!)
Over all it has worked very well and I am very pleased with it. I definently recomend adding amber over the standard rgb.
I decided to go with rgba insted of rgb because it has a higher cri and boosts the amount of light in the red end of the spectrum, allowing you to increase the amount of green and blue to make it white again therefore increasing the brightness🙂
I got the idea and dimming circuits from Dan's great Instructable found here.
My light edmits a calculated 2400 lumens of white light at 70watt (includes diffuser loss), this makes it a lot brighter and about three times more efficiant than my old halogen light (4x40w)
The LED's are Luxeon Rebels I have used two strings of red (14 led's or 7 per string) each at 350ma (700ma in total), 6 PC Ambers at 700ma, 6 Greens at 1A and 6 Royal blues at 1A. All the LED's were the highest lumen bin avaliable.
The total cost was about £255 or about $407 at the current exchange rate.
As you can see I have used a large heatsink and a quiet pc fan (Noctua NF-P12)to keep it cool 😎 and I have used a frosted piece of perspex as a diffuser.
The LED's were soldered onto an mcpcb then bolted using nylon bolts onto the heatsink with thermal paste for excelent heat transfer. in the photo only the red and green LED's are on also you can see the thermistor in the centre.
The controller is compleatly analogue as and each colour is compleatly adjustable. The sliders are for the main ajustment and the dials are for precise colour adjustment. The small LED's tell you when it is on, when the fan is on and when it has overheated and turned off.
These pics shows the placement of LED's
This shows the inside of the control box showing the power suply and circuits.
Beam shot photos taken with my 3 megapixel phone set to daylight.
Incandesent light
rgba set at a warm white
rgba set at a neutral white
rgb, note the oranges look redder
The circuit diagram for those who are interested. I set the fan to come on at around 40 centigrade and the overheat shutdown at around 50 centigrade these figures are lower than the original (60 and 80) because the fan, once it turned on, slowed to an compleatly inaudiable crawl so I lowered the temperature to increase its lifetime and efficiancy.
The wavelengths from luxeon datasheet, since the amber is a blue LED with a phospher (4 times more efficiant than normal ambers) it has a wider spectrum so it is more of a warm white/amber led. (I drew the amber!)
Over all it has worked very well and I am very pleased with it. I definently recomend adding amber over the standard rgb.
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