The one-piece Franklin type bifocal is a straight-top bifocal of simple design which offers unique opportunities for controlling prism power and field aberrations in both the distance and reading portions of the lens through freedom of placement of the optical centers. Practical tables and charts are presented which allow the optometrist to take full advantage of the optical properties of this type of lens.
*Read before the annual meeting of the American Academy of Optometry, Chicago, Illinois, December 12, 1967. For publication in the March, 1969, issue of the American Journal of Optometry and Archives of American Academy of Optometry.
†Lens Development Manager. Fellow, American Academy of Optometry.
‡Lens Development Engineer.
© 1969 American Academy of Optometry