TABLE OF CONTENTS An optical element is a single irreducible optical lens or mirror.
An optical component may be an element, or several elements which are treated as a unit.
An optical member is one of two parts of a system, separated by a diaphragm: the front member and the back member.
An optical system is a complete set of optics which produces an image of the desired size, in the desired location, and with the desired orientation.
In order to simplify and organize the design of optical systems, it is convenient (especially in preliminary work) to treat an optical system as an arrangement of components, each with zero thickness. In preliminary work we can deal with components as simple, unified pieces. A component may consist of several elements, but in creating a system layout scheme, we simply specify the power (or focal length) of a component and its location. When the initial layout is done, the zero thickness components are replaced by real, physically possible components.
This avoids having to handle the system by means of surface-by-surface calculation. To this end we can introduce the paraxial ray height y into the equations of Sec. 2.3, just as we did in Sec. 3.3.
An optical component (which may be made up of a number of elements) is shown in Fig. 4.1 with its object a distance s from the first principal plane and its image a distance s' from the second...
