Applied Digital Optics: From Micro-optics to Nanophotonics

9

Dynamic Digital Optics

The focus in Chapters 3–8 has been set on static digital optics, including waveguides, micro-refractives, diffractives, holographic, hybrid and sub-wavelength optical elements fabricated in hard materials such as glass and fused silica, or recorded in holographic emulsions. In Chapters 4,6 and 8, the third dimension of space was introduced (through 3D displays). In this chapter, the fourth dimension (i.e. time) will be introduced. This chapter reviews dynamic digital optics that can be implemented on technological platforms similar to the ones described previously, and on new platforms such as LCs, MEMS and MOEMS.

9.1 An Introduction to Dynamic Digital Optics

Dynamic optics and dynamic optical micro-devices are an emerging class of optical elements that have a high potential to provide solutions for demanding applications [1], especially in the consumer electronics, transportation, optical telecoms and biotechnology market segments (for product descriptions, see also Chapter 16). Dynamic optics opens a whole new window for the use of digital optics. New applications are being proposed every day and this is becoming the fastest-growing segment of the digital optics realm.

9.1.1 Definitions

Dynamic digital optics can be classified into three groups (see Figure 9.1):

• switchable digital optics;
• tunable digital optics; and
• reconfigurable digital optics.

Note that there is an additional sub-field, similar to tunable optics, called software optics. This is a ...