- Graham I take it that you are reinforcing the point, that the loses will be significant and the more desirable solution is to concentrate the light down to aMessage 1 of 47 , Mar 6 2:11 AMView SourceGrahamI take it that you are reinforcing the point, that the loses will be significant and the more desirable solution is to concentrate the light down to a point source to enable projection.We had discussed the idea of using fibre optic material to gather up the light from the large array and by reducing the fibre diameter by a heat drawing concentrate the light to a smaller diameter effectively tending to a point source for the light. Unfortunately that was beyond my DIY capabilities.My recent submission is an alternating method using a light guide. It would be difficult to accommodate any LED module bigger than the 30W unit in the space inside my projector.I found a company called AVAGO ( http://www.avagotech.com ) with a lot of useful papers on the LED technology and attached is the Applications Brief on Light Guide technologyOn 6 March 2013 09:22, Graham Stabler <grezmos@...> wrote:
This shows so clearly that they are all basically the same LED element made in to larger and larger arrays, the energy density is the same for each so as you increase power to hopefully get around the losses what you really do it just widen the source. I suspect that most of the light from the outer elements will never leave the projector and if it does will only blur the image.I'd be interested to know if there are any commercial projectors using LED arrays *of this sort* and if so what optics they use. I would also be interested to know if there have been many conversions of projectors to use LEDs that have produced a decent output.Graham--RegardsFrancis Leach
- The other issue we have run into is the waste heat converted by a lamp. Compact designs require lots of airflow to keep the electronics cool. The heat may alsoMessage 47 of 47 , Mar 7 6:26 AMView SourceThe other issue we have run into is the waste heat converted by a lamp. Compact designs require lots of airflow to keep the electronics cool.
The heat may also be conveyed to the photopolymer in the vat to reduce the viscosity via a heatpipe. If you use LED's then you can just add a cartridge heater to the vat.
--- In email@example.com, "doyle_arthur@..." <doyle_arthur@...> wrote:
> Lamp life, to my view, is the only benefit that can be gained by using leds.