The visible VCSEL (Vertical Cavity Surface Emitting Laser) in the red spectral range emits coherent light at 670 nm. The threshold current (typically 2 mA) is smaller by a factor of 10 compared to regular ELEDs or laser diode. The optical output power is typically 1 mW.
The red VCSELs are available in TO-46 housings (with optional lens caps), plastic housings, or as chips. Therefore they are optimally suited for applications that require a small form factor or a low operating current, e.g. portable scanners. Additional applications include position sensing, medical devices and, of course, data transmission systems using plastic optical fibers (POF). The small divergence of typically 2° for the lens cap version allows for an optimal coupling efficiency into the POF.
