The LED I chose is a Seoul Semiconductors single chip. It is pretty expensive, but it is powerful giving a very bright light. It provides also an excellent colour blending.
It could be replaced by cheaper and probably equivalent ones; when I designed this, it was the only one suitable I could find.
Due to the LED's high power rating it is absolutely necessary to provide it with a reasonable heat sink like the one you see in the photos; before putting the finished circuit in a case check the LEDs for heat at maximum intensity on all of the three colours. The current limiting resistors I chose match my LED only !
I chose a 10% less than the typical recommended V-I values on the datasheet curves.
Being the circuit in a plastic case it is not safe to pull dissipation any higher while a metallic case with an external dissipation scheme might make safe to pull the LEDs currents a make a more powerful beam.
Different LEDs do have different ratings. Check the datasheets for maximum dissipation and recommendations for your LED.
I purchased my LED online from Distrelec
carries them also.
The drivers are surplus NPN transistors over-dimensioned for the current required. Less powerful TO126 encased NPNs should do fine. As the Transistor are driven with PWM, their dissipation is kept to a minimum so heat sink is not necessary.
The IR receiver is one i savaged from a dead TV toghether with the remote control. The receiver has a metallic screen that should be grounded to 0V. Some newer small-sized ones are from Temic and can be bought from the same sources as above. Practically any receiver works fine, provided that it has 5Volt logic levels (and supply) and has the same (or close) carier frequency as the remote transmitter (typically 38-50kHz). When demolishing a TV or any other remote controlled piece of equipmentm, a good rule is to save both the remote and the receiver. By the way, I love saving transformers, VFD, motors as well, but that's another story.
This lamp uses an european RC5 standard for Philips TV remotes; Any programmable remote control that supports Philips TVs should be fine, I tried one and it works.
Both remote decoding and PWM generating routines should be understandable from the source code I commented.
The circuit must be supplied from a 5 Volt, 1A good source. Initially I used a linear voltage regulator IC on the board into the case, but the heat generated by the regulator was way too much to be easily dissipated from within the box, so I removed it and now I'm using anexternal waal adapter with a regulated 5V 3A output. The LEDs are powered directly from the 5Volt, so any variation would trash your precise calculations for currents to flow through the LEDs, possibly damaging them. So, the better and stable the supply, the better.
The case I chose is a Teko TB9, it looks elegant to me and small transparent objects can be placed on top of the case+LED without the risk of falling.