In the preface I think it is better if I abandon the formality of the text and address you the reader, directly.

As I hope you will have gathered from the title, this is a book that attempts to lay out the basis for the design of analog optical links. Let me give an example that should drive home this point. It is customary in books on lasers to start with an extensive presentation based on the rate equations (do not worry at this point if you do not know what these are). In this book we also discuss lasers, but the rate equations are relegated to an appendix. Why? Because in over 15 years of link design, I have never used the rate equations to design a link! So why all the emphasis on the rate equations in other texts? Probably because they are targeted more to, or at least written by, device designers. The view in this book is that you are a user of devices, who is interested in applying them to design of a link. Of course to use a device most effectively, or even to know which device to choose for a particular link design, requires some knowledge of the device, beyond its terminal behavior. To continue the laser example, it is important to know not only what the laser frequency response is, but also how it changes with bias.