Chapter 11: Low-Power Laser Applications

ABOUT THIS CHAPTER

The final three chapters of this book cover laser applications, which are many and diverse. To keep the topic manageable, we will break them into three broad groups: those requiring little power (such as playing CDs), those requiring high power (such as cutting and welding), and those in scientific research, such as studying the properties of atoms and molecules. The division between low and high power is somewhat arbitrary, based on how the lasers affect the materials they illuminate. The intent is not to list everything, but to list the most important, interesting, and illustrative applications to help you understand laser applications in general.

This chapter covers applications that require low laser power, typically well under a watt. A laser with such little power does not have a dramatic effect on the objects it strikes, but it may make minor changes, such as exposing photographic film. As we will see, there are many types of low-power laser applications. In some, the laser is little more than a high-performance light bulb, but for others special features of laser light, such as coherence or tight beam collimation, are essential. In most cases, the laser light is communicating or processing information, whether it is playing music from an audio CD, sending signals through a fiber-optic communication network, or printing information on a page.