2020–2021 BCSC Basic and Clinical Science Course™
3 Clinical Optics
Chapter 1: Geometric Optics
The Reduced, or Equivalent, Optical System
A complex multiple lens system can always be analyzed sequentially, but the process is tedious and must be repeated from the beginning for each source object location. However, we can calculate an equivalent optical system consisting of just 1 pair of principal planes, 1 pair of focal points, 1 pair of nodal points, and 1 power. The paraxial properties of this equivalent system, called the reduced optical system, are identical in every respect to the original system consisting of multiple lenses. Thus, once the equivalent system is determined, we need only a single vergence equation calculation to locate the image of any object. A simplified reduced model for the human eye (Figure 1-22) is discussed in Chapter 3.
Excerpted from BCSC 2020-2021 series : Section 3 - Clinical Optics. For more information and to purchase the entire series, please visit https://www.aao.org/bcsc.