VCSELs in the Information Age

Vertical Cavity Surface Emitting Lasers (VCSELs) emerged from scientific curiosity to economic reality in 1996 when Honeywell introduced the world’s first commercial products. The VCSEL was viewed as an enabling technology that quickly supplanted edge emitting laser technology in the data communications market. Edge emitting lasers suffer from several inadequacies, such as poor reliability (both in the dc and ac sense), strong relaxation (turn on) oscillations, and poor coupling efficiency to optical fiber. The VCSELs produced by Honeywell have achieved reliability projections in excess of 10 Million hours of operation at nominal conditions while maintaining optical signal integrity during aging. In addition the physics of the VCSEL microcavity ensure well damped, extremely high frequency relaxation resonance, and they emit circularly symmetric, non astigmatic optical beams. This new laser source, coupled with the burgeoning optical communications market has triggered a phenomenal increase in the number of VCSEL shipments. To date, many millions of VCSEL based optical transceivers have been deployed. Most of the VCSELs in use today are for data communications systems operating on multimode optical fiber, and running at speeds up to 1.25GBd in applications supporting both ethernet and fibre channel.