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5mm LEDs and a real good light?

I recently came across an article which mentioned that 5mm LEDs are not suitable for general lighting. I do not agree with this view.
  • A 5mm LED will produce much less heat and hence the heat can be managed with a proper PCB design and without using any heatsink.
  • A correctly driven 5mm White LED will live its rated life, which in case of a good manufacturer is easily in the 30,000 to 50,000 bracket.
  • The ageing of phosphor and gradual change in colour spectrum is an issue faced by all white LEDs and not only 5mm LEDs.
For a neutral assessment check this US Government website:
http://light.lbl.gov/technology-assessment.html

I have designed and made a board with 18 numbers of 5mm (hat shaped for larger angle) white LEDs. This board is ideally suited for low light applications like stairways, corridors, and in some rural lighting applications. With LEDs from Yetda I have got very consistent light and colour. In my test I could get 47 Lux at 1 metre from the PCB. and about 170 Lux at 0.5 Metres.
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