II-3 REFRACTION AT SPHERICAL SURFACES

II-3  Imaging with Spherical Lenses           
              Ray Tracing under the Snell's Law and the Paraxial Approximations

                  II-3.1   Ray tracing and imaging through a spherical interface                                                                                        
                                  Comparison between spherical and aspherical lenses                         

                                  II-3.1.A   General Terminologies:   Ray Tracing through a Spherical interface                                       
                                                    The paraxial approximation
                                                     Conventional terminologies

                                                            Real and virtual image

                                                            Real and virtual object

                                                      Conventional sign of the radius of curvature

                                                Positive radius of curvature (convex spherical interface)

                                                Negative radius of curvature (concave spherical interface)

                                  II-3.1.B  Imaging through a    Spherical-Interface   and through a   Spherical Thick-Lens
                                                    under the paraxial approximation                                                                                                              

                                   The lens equation  (Imaging through a spherical interface)

                                                    The focal point  Fi  

                                                      Imaging an object point located off axis

                                               Lateral Magnification

                                                    Examples:  Imaging through a convex spherical interface; Imaging through a thick spherical lens

                                                    Numerical aperture
                                                    Increasing the light gathering power of a lens: Oil immersion lens

                  II-3.2  Thin lenses

                                  II-3.2.A   Imaging Through Thin lenses                                                                                                                            

                                  II-3.2.B   Newtonian Form of the Lens Equation 

                                  II-3.2.C  Thin Lenses Combinations                                                                                                                                  

                                  II-3.2.D  The Eye                                                                                                                                                                        

                                  II-3.2.E   Relative Aperture and f-number