We started by covering some background.
Bookham enjoyed a 20-year life under its own name and progressed by a series of acquisitions before eventually being US domiciled and then merged with Avanex Corp. in 2009. Under the name Oclaro, it has been one of the largest suppliers of optical components, modules and subsystems for telecommunications. Oclaro was in turn acquired by Lumentum in December 2018.
At the start of his career Rickman was looking to realize commercially what he had studied for his PhD under Professor Graham Reed, then at the University of Surrey. This was the ability to create wave guides and electronically-controlled switches in silicon.
Back then it was clear to Rickman that the nascent optoelectronics sector could make use of the economies of scale enabled by silicon microelectronics manufacturing and that it would be possible to create some reasonably complex optical circuits in silicon.
The waveguides tend to be made as ridges in the silicon so that the physical boundary of the silicon defines the channel. And by manufacturing with silicon-on-insulator wafers it is possible to define the fourth wall of the waveguide as the buried silicon-oxide layer.
"Optical fibre communications and some sensing applications were the initial possibilities," Rickman recalls." Approaches to sensing were usually done by allowing some parameter to deflect or affect the light path and measure the comparative time delay versus a reference path. This made for the possibility of extremely sensitive measurements in a small form factor in a wide number of areas.
Rickman remembers that sensor applications were the initial thrust of the company but it was communications where the first traction was obtained with customers. The 1990s was a time when optical fibre was being deployed in urban communications and the access market and with the adoption of the Internet came the dot-com boom, he said. This resulted in sensing being put on the back burner.
Next: Intel and Cisco