Light Emitting Diodes (LEDs), Laser Diodes, and Vertical Cavity Surface 
Emitting Lasers (VCSELs) are finding their way into more and more 
applications today.  These applications include facial scanners for 
security, LIDAR for collision avoidance and self-driving cars, as well 
as optical telecommunications.  While the VCSEL is a relatively simple 
device in terms of its electrical behavior, it also has optical 
properties and behaviors that must be tested as well.  This requires a 
different approach to testing than with a standard discrete diode.  
Engineers need to test both the electrical and optical properties of 
these devices, sometimes at very high frequencies.  

    Light Emitting Diodes (LEDs), Laser Diodes, and Vertical Cavity Surface 
Emitting Lasers (VCSELs) are finding their way into more and more 
applications today.  These applications include facial scanners for 
security, LIDAR for collision avoidance and self-driving cars, as well 
as optical telecommunications.  While the VCSEL is a relatively simple 
device in terms of its electrical behavior, it also has optical 
properties and behaviors that must be tested as well.  This requires a 
different approach to testing than with a standard discrete diode.  
Engineers need to test both the electrical and optical properties of 
these devices, sometimes at very high frequencies.