Characterizing Beam Polarization @thorlabs

Uploaded December 2021 | Updated September 2026, 2 hours ago

In this final part of our light characterization series, Manfred Gonnert will further define and characterize polarization. He will provide application examples to help with laser beam alignment, understanding polarization-handedness, manually measuring Stokes parameters, and preventing unwanted interference.

To view our Polarization instrumentation products, please visit thorlabs.com/navigation.cfm?guide_id=39&ytid=gXjNbWRy1dM.

To view more of our recorded webinars, visit thorlabs.com/newgrouppage9.cfm?objectgroup_id=13891&ytid=gXjNbWRy1dM.

Installing Fiber Inserts for Thorlabs Large Diameter Splicers and Glass Processors

Thorlabs Mobile Photonics Lab One Year Anniversary

Intro to Photonics Experience | Thorlabs Mobile Photonics Lab

Optimizing the Transient Absorption Signal in the EDU-TRAS1(/M) Educational Kit

Foodshed Alliance | Thorlabs and Our Community

$Holiday Laser Lights | Photonics in Everyday Life Have you ever wondered how holiday laser light displays work? These laser holiday displays project hundreds of laser beams, but how can so many lasers fit into such a small package? You might be surprised to know these laser displays only need a single laser. They use something called diffraction gratings to diffract the one beam into many. Diffraction is the property of waves that allows the bending around corners. It’s a result of the waves getting bent from obstacles and edges they encounter. This can be seen when placing small obstacles like a strand of hair in the beam of a laser. The diffracted waves at the obstruction’s edges interference, creating complicated patterns of light. When small line structures are placed side by side, they form a diffraction grating and can generate multiple beams even if the structures themselves are transparent like glass or plastic. By stacking multiple diffraction gratings in a row in different orientations, a dynamic pattern of beams is created.$

Collimate a Laser with a Shear-Plate Collimation Tester (Viewer Inspired) | Thorlabs Insights

Soaking Up Photons at UNCC and Clemson VLOG Ep. 6

Optomech Basics: Securing to Posts with Cap Screws | Focused Insights

Profiling Beam Shape and Waist Laser Science

$How Lights Polarization Can Change After Reflecting from a Metal Mirror | Thorlabs Insights Metallic mirrors are frequently used to steer light through optical setups. The beam’s direction and shape are typically monitored and optimized after mirror reflection, but reflection-induced changes to the beam’s polarization state are often not considered. Disregarding these changes is reasonable if the application is not polarization-dependent, but it can lead to unexpected results if the application is sensitive to polarization. Reflection from a metallic surface can change light’s polarization state because metals have complex refractive indices, which are different for P- and S-polarized light. When light is purely S- or P-polarized, incident and reflected polarization states are the same. However, linearly polarized light that is a combination of S- and P-polarized light will usually be reflected as elliptically polarized light. A further complication to consider is that the polarization state of the incident light can be changed by just tilting the mirror, since the polarization state is based on the plane of incidence. In this demonstration, we explore these concepts and show what to expect when different linear polarization states reflect from a protected silver mirror oriented at a 45° angle. The polarization state of the incident light is determined using measurements taken with a polarimeter constructed from a quarter-wave plate, linear polarizer, and power sensor. Our Stokes parameter calculations take into account the wave plate’s actual retardance, which improves accuracy. The polarization state of the reflected light is measured using a turnkey polarimeter, whose polarization ellipse display is used to visualize the dynamic polarization changes that occur as the incident linear polarization state rotates between S- and P-polarized light. 00:00 Introduction 01:13 Polarization After Reflection 03:31 Input Beam Setup Overview 04:14 DIY Polarimeter Overview 04:52 Measure QWP Retardance 7:15 Measure Stokes Parameters 8:25 Reflection of P-Polarized Input 9:34 Reflection of S-Polarized Input 11:04 Other Linearly Polarized Inputs Components used in this demonstration include: - HRS015B Stabilized HeNe Laser: https://www.thorlabs.com/newgrouppage9.cfm?objectgroup_id=5281&pn=HRS015B&YVI=33 - C1513 V-Clamp Post Mount, Kinematic: https://www.thorlabs.com/newgrouppage9.cfm?objectgroup_id=174&pn=C1513&YVI=33 - PM4 Clamping Arm: https://www.thorlabs.com/newgrouppage9.cfm?objectgroup_id=1811&pn=PM4&YVI=33 - Posts, Ø1.5”: https://www.thorlabs.com/newgrouppage9.cfm?objectgroup_id=1313&YVI=33 - PB2 Post Base: https://www.thorlabs.com/newgrouppage9.cfm?objectgroup_id=1931&pn=PB2&YVI=33 - SM1B2 Isolator-to-SM1 Adapter: https://www.thorlabs.com/newgrouppage9.cfm?objectgroup_id=2996&pn=SM1B2&YVI=33 - IO-3D-633-VLP Optical Isolator, 633 nm: https://www.thorlabs.com/newgrouppage9.cfm?objectgroup_id=2996&pn=IO-3D-633-VLP&YVI=33 - RSP1C Rotation Mount: https://www.thorlabs.com/newgrouppage9.cfm?objectgroup_id=246&pn=RSP1C&YVI=33 - WPQSM05-633 Quarter-Wave Plate, Pseudo-Zero-Order, 633 nm: https://www.thorlabs.com/newgrouppage9.cfm?objectgroup_id=7234&pn=WPQSM05-633&YVI=33 - SM1A6 Threading Adapter, SM1-to-SM05: https://www.thorlabs.com/newgrouppage9.cfm?objectgroup_id=1524&pn=SM1A6&YVI=33 - RSP1X225 Rotation Mount, Indexed or Continuous Rotation: https://www.thorlabs.com/newgrouppage9.cfm?objectgroup_id=246&pn=RSP1X225&YVI=33 - LPVISC100-MP2 Mounted Linear Polarizer: https://www.thorlabs.com/newgrouppage9.cfm?objectgroup_id=752&pn=LPVISC100-MP2&YVI=33 - PF10-03-P01 Silver Mirror: https://www.thorlabs.com/newgrouppage9.cfm?objectgroup_id=903&pn=PF10-03-P01&YVI=33 - NX1N Optics Mount, 16 Indexed Positions: https://www.thorlabs.com/newgrouppage9.cfm?objectgroup_id=1546&pn=NX1N&YVI=33 - WPMQ05M-633 Quarter-Wave Plate, Multi-Order, 633 nm: https://www.thorlabs.com/newgrouppage9.cfm?objectgroup_id=713&pn=WPMQ05M-633&YVI=33 - S130C Power Sensor: https://www.thorlabs.com/newgrouppage9.cfm?objectgroup_id=3328&pn=S130C&YVI=33 - PM400 Power Meter: https://www.thorlabs.com/newgrouppage9.cfm?objectgroup_id=10562&pn=PM400&YVI=33 - SMR1 Mount, SM1 Threads: https://www.thorlabs.com/newgrouppage9.cfm?objectgroup_id=1433&pn=SMR1&YVI=33 - Lens Tubes, Ø1”: https://www.thorlabs.com/newgrouppage9.cfm?objectgroup_id=3307&YVI=33 - PAX1000VIS Polarimeter: https://www.thorlabs.com/newgrouppage9.cfm?objectgroup_id=1564&pn=PAX1000VIS&YVI=33 - KM200PM Kinematic Prism Mount: https://www.thorlabs.com/newgrouppage9.cfm?objectgroup_id=1811&pn=KM200PM&YVI=33 - MSB46 Optical Breadboard, Mini-Series: https://www.thorlabs.com/newgrouppage9.cfm?objectgroup_id=6327&pn=MSB46&YVI=33 - R2 and R2T Post Collars: https://www.thorlabs.com/newgrouppage9.cfm?objectgroup_id=2003&YVI=33 For more photonics how-to videos, visit: https://www.thorlabs.com/newgrouppage9.cfm?objectgroup_id=14062&YVI=33$