780nm VCSELs for home networks and printers

A 780 nm multi-mode VCSEL, to meet the requirements for a new GI plastic optical fiber, are reported. It has 4 spots driven simultaneously like a single spot and hence the optical power needed from each spot is reduced to 1/4. As a result, the MTTF obtained is well over 200,000 hr at 60°C under 3 mW operation, with a narrow beam divergence angle of less than 18° (1/e²). This VCSEL also shows wide-open 5 Gbps eye diagrams at standard driving conditions, which is sufficient for most home network applications. Applications using this VCSEL and Lumistar, such as optical DVI (digital visual interface) and GBIC (Gigabit interface connector) modules are shown too. Furthermore, a 780 nm VCSEL array with independently addressable 32 spots, for laser beam printer applications, is reported. Each spot has a single-mode optical power of more than 1.2 mW at 60°C and their uniformity is within ±1%. A high resolution of 2400 DPI and a print speed of 12.5 ppm, in color, was achieved by incorporating this array as an optical source.