With free-form lenses (also called digital high-definition lenses), the fabrication of the lenses from wearer's eyeglass prescription is optimized with computer-controlled surfacing equipment that is much more precise than conventional tools.
Medical Imaging began with radiography after the discovery of x-rays in 1895 by Wilhelm Roentgen, rÃ¶ntgen A german professor of. physics
Obstetric ultrasonography may also be used to detect pregnancy. Obstetric ultrasonography was first practiced in the 1960s; the first home test kit for hCG was invented in 1968. The kits went on the market in the United States and Europe in the mid-1970s.