Hitroberts,nThank you for your reply. It was really helpful.nRegarding reply 3) above:nHow should I refer to the global mesh constraint here in the current example? If edges per wavelength is 2 and my wavelength is 1.55 micron, so is it quantitatively higher or lower than added mesh constraint saying max edge length is 0.01micron? nThanks, nTali M.