The Ronchi test is one of the simplest and most powerful methods for e
valuating and measuring the spherical aberration of an optical system
and is an accurate method for measuring the focal length of an IOL (Ca
rretero at al., 1992, 1993). The accuracy of lens power specification
is a crucial factor for bifocal intraocular lenses (IOLs). Therefore,
the powers of these IOLs must be tested to verify that the lenses have
been manufactured according to the design. In this paper we suggest t
he use of the Ronchi test for testing the two powers of bifocal IOLs.
(C) 1997 The College of Optometrists.