Condenser aperture-A small laser-bored gap in the flat strip of molybdenum put close to the condenser lens that helps to Restrict spherical aberration.Saturation Point-The purpose at which good electron emission in the gun is attained with no shortening the filament lifetime appreciably.Khi ?i?n tho?i ???c g?n tem này, khách hàng ???c ??m b?o qu