Optical Extinction Ratio (OER) and Polarization Extinction Ratio (PER)

This page explains the concepts of Optical Extinction Ratio (OER) and Polarization Extinction Ratio (PER), terms commonly used in the field of optics. We’ll cover their definitions and the formulas used to calculate them.

What is Optical Extinction Ratio (OER)?

• The Optical Extinction Ratio (re) represents the ratio between two optical power levels of a digital signal.
• This signal is typically generated by an optical source, such as a laser diode.
• The formula for OER is: re = P1 / P0
• It’s usually expressed in decibels (dB) or as a percentage.

What is Polarization Extinction Ratio (PER)?

• The Polarization Extinction Ratio (PER) is the ratio of optical powers measured using two perpendicular polarization types, such as Transverse Electric (TE) and Transverse Magnetic (TM).
  • TE refers to Transverse Electric polarization.
  • TM refers to Transverse Magnetic polarization.
• PER is particularly useful in characterizing optical fibers.

OER and PER Formula

Both Optical Extinction Ratio and Polarization Extinction Ratio use the same basic formula:

Where:

• P1 is the power amplitude when the light source is ON.
• P0 is the power amplitude when the light source is OFF.