square millimeter
1.The nanotechnology experts at the Technion institute in Haifa say the text measures less than 0.5 square millimeter surface.
2.Most laptop computers now come fitted with high-capacity hard drives that pack an unprecedented amount of data into each square millimeter.
3.A unit of retinal illumination, equal to the amount of light that reaches the retina through 1 square millimeter of pupil area from a surface having a brightness of 1 candela per square meter.
4.I admired his frugality-Rick would sew up the holes in his socks rather than buy new ones, keep cars until they fell apart （ we still have the 1975 Camaro he drove on our first date ） and fill up every square millimeter of a note card.
5.Currently the biosensor is a 25-millimeter-square plastic chip that has a meandering flow line running through it.
