By the time I'm old and wrinkly, I doubt I'll care what my tattoo looks like as I'll be more bothered about how loose the skin is on my face... or where I've left my false teeth!

If you had a 1m^2 solar cell you wouldn't use a mirror that focused 1m^2 of light into a 1cm^2 dot, you would use a much bigger mirror that focused 25m^2 of sunlight onto the original 1m^2 solar cell.