Hi, I was wondering if it would be possible to focus light down to a small point using the following method: Construct a pyramid from four identical triangular mirrors (three would also work), with the mirrored side facing inwards of course. Do not put a base on the pyramid, but instead use the open end of the pyramid to gather light (point it towards the Sun). A small hole should also be made on the opposite side of the pyramid (where the focused light will emerge). Would the light be focused down by the mirror setup or would the light simply bounce around inside and come back out the top? I have come to the conclusion that the walls of the pyramid must be fairly steep for this to work, but I'm not sure if this assumption is correct. I can't seem to convince myself either way. All help will be greatly appreciated.