Today’s data center networks operate at the cutting edge of fiber optic link and electronic packet switching capabilities. The immense bandwidth requirements of next-generation data centers will stress the limits of electronic switching, providing an opportunity for transparent optical switching to deliver an overall cost-bandwidth advantage. However, current optical switching approaches are not optimal for data center networks because they either do not scale to large port count, reconfigure too slowly, or introduce insertion loss or crosstalk levels incompatible with cost-effective optical transceivers. This dissertation presents the design and demonstration of a novel optical switch architecture more well-suited to data centers, along with the design of overall network architectures that employ this new switch architecture.

The dissertation begins at the physical layer with a scalability assessment of conventional microelectromechanical systems (MEMS) based beam-steering optical switching. MEMS beam-steering cross-connects are the only optical switching technology which has demonstrated the large port count and broadband, polarization-insensitive transmission necessary to approach the scale and link power budgets of modern data center networks. The shortcoming of conventional cross-connects is their slow reconfiguration time, which prevents them from effectively provisioning bandwidth on the timescales necessary for a potentially large fraction of data center traffic. First-principles analysis at the device level indicates that, rather than a straightforward redesign of existing crossbar switches, entirely new switch architectures are necessary to meet the optical switching performance required for data centers.

Motivated by physical layer analysis, a novel selector switch architecture is presented which, through an unconventional approach of relaxing the degree of switch configurability, allows MEMS beam-steering switching elements to scale to microsecond-class response speeds while supporting large port count and low loss switching. The switch is partially configurable in that it selects port mapping patterns from a small hardware library of preconfigured mappings, rather than implementing arbitrary mappings like a crossbar. The physical architecture of the switch uses pupil-division and relay imaging, permitting designs compatible with single-mode or multi-mode fiber optics. The design, fabrication, and experimental characterization is presented for a proof-of-principle prototype using a single MEMS comb-driven micromirror to achieve 150 microsecond switching of 61 single-mode ports between 4 preconfigured port mappings. The scalability of this switch architecture is demonstrated with the detailed optical design of a low-loss 2,048-port selector switch with 20 microsecond switching time.

Because conventional network architectures are typically based on crossbar switches, new overall network architectures are required to utilize the partial configurability of selector switches. The dissertation concludes with an investigation of network architectures based on selector switches, showing, perhaps unexpectedly, that partially configurable networks can deliver aggregate bandwidth approaching that of a fully-provisioned electronically-switched network for common network traffic patterns, but for reduced cost, cabling complexity, and power consumption.

The approach taken in this dissertation of developing switch and network architectures which balance scalability at the physical layer and performance at the network layer will hopefully aid in the design of future optical data center networks.

There is an ever present demand to increase the capability and performance of optical imagers while decreasing their physical size and cost. In order to achieve this, these devices must be engineered as complete systems and integrated together, rather than treated as disparate independent elements. This dissertation presents several examples of this concept. Specifically, it describes the integration process, including the design, simulation, fabrication, assembly, and characterization of several micro-optic imaging systems.

These systems include a wink-controlled polarization-switched telescopic contact lens, which switches between magnified and unmagnified vision by detecting a user's winks with an external pair of liquid crystal shutter glasses. A folded monocentric imager with deformable mirror focus splits a monocentric lens in half by utilizing symmetry and refocuses by changing the curvature of a flexible fold mirror in contact with a gel core. A sequential-capture panoramic light field camera uses a high resolution image relay to transfer the light field passing through a monocentric lens and microlens array to an image sensor. The entire relay is rotated around the monocentric objective lens to capture a series of exposures which are combined to produce the final panoramic light field image. A panoramic single-aperture multi-sensor light field camera uses an array of consolidating light field image sensors behind a monocentric lens to create a contiguous panoramic light field image in a single capture.

In addition to these systems, several future directions under ongoing research are described. First, a three-orthogonal discrete field light field camera which senses depth information in three separate directions using a single monocentric lens for visual odometry is presented. Finally, preliminary lens designs for a full field and field-expanded single-aperture sensor array cameras are documented. These lenses produce images that can be directly captured, and one of which extends the field of view beyond the hemisphere. In addition to their optical performance, considerations around cost reduction, manufacturability, and mass production for the consumer market are discussed.