Firecomms VCSELs (Vertical Cavity Surface Emitting Lasers), the only visible/red VCSELs in production worldwide, are highly efficient lasers with low power consumption and high speeds in excess of 3.2 Gbps. While the overwhelming majority of commercial VCSEL products operate at a wavelength of 850 nm, Firecomms is the first company to commercially offer VCSELs in the visible/red wavelength range 650-690 nm.

Firecomms VCSELs share the same features and advantages associated with 850 nm VCSELs, although the precise semiconductor design, processing and device characteristics are unique. By using complex AlGaInP-based active regions, a material system not used in 850 nm VCSELs, Firecomms VCSELs operate in the 650-690 nm range. This system requires epitaxial design, growth, and processing strategies unique to our VCSELs.

Firecomms visible VCSELs compete with existing visible edge-emitting lasers and open up new applications for which visible edge-emitting lasers are entirely unsuitable or have hopelessly inadequate performance. Unlike edge-emitting semiconductor lasers which emit lasing light from the perfectly flat edges of the laser chips, the VCSEL emits the lasing light perpendicular to the top surface of the chip. The emission direction of the VCSEL is achieved by depositing a pair of high reflectivity mirrors, known as distributed Bragg reflectors (DBRs), as part of the semiconductor deposition process itself, which creates a laser with a lasing cavity in the vertical direction. To create the VCSEL’s semiconductor DBR mirrors requires a significant increase in the complexity of the semiconductor deposition process (epitaxial growth).

VCSELs offer a number of unique advantages: a threshold current that is low and stable with temperature so that electricity is converted to light with a very high efficiency; the ability to be modulated at very high frequencies; a circular output beam with low divergence, simplifying the optical system; and the ability to be tested while in wafer form, requiring minimal post-processing after separation from the wafer, and suitability for simple packaging styles so that the high volume costs can be very competitive. In addition, our single-mode VCSELs operate at a single wavelength, and with a stable polarization that is important for many applications.

The operating current of a visible VCSEL can be a factor of 10 lower than that of an edge-emitting laser. That means that when used in a battery-operated device, a VCSEL can significantly prolong battery life when compared to an edge-emitting laser.

High-speed graded index plastic optical fiber (GI-POF) is an exciting new optical media that can be used for the low-cost delivery of high-speed data over relatively short distances (cms to 50 m), such as within consumer electronic devices or the home. These fibers require optical sources with emission wavelengths in the region of 650–670 nm that can match the high-speed (Gbps) performance of the new fibers. Firecomms multi-mode VCSELs can be modulated over 3.2 Gbps and, unlike edge-emitting lasers with limited bandwidth, have excellent emission beam properties that result in high fiber coupling efficiencies.