Capturing and Sharing Insights

Having the right information can save hours of work and frustration, but a lot of this valuable knowledge is not found in textbooks, taught in classes, or easily located by searching online sources. Much of this knowledge is gained through experience and trapped in the minds and lab notebooks of people working in the world of photonics.

Thorlabs is on a mission to collect these tips, tricks, guidelines, and practical techniques into a book of knowledge we call Insights. Click on the following links or browse the tabs on this page to read the Insights we have recorded as of today. This collection is always growing, so check back soon to see what new Insights have been added.

 

 

The Field of Photonics

• What is photonics?

Alignment of Optical Components

• What is a procedure for correcting a laser's beam pointing angle?
• How are two mirrors used to align a laser beam along a different path?
• What is the required spacing between two beam-steering mirrors?

 

Best Lab Practices

• Clamping Forks: Tip for Maximizing the Holding Force
• Optical Tables: Clamping Forks and Distortion of the Table's Surface
• Washers: Using Them with Optomech
• Electrical Signals: AC vs. DC Coupling
• Fiber Collimators: Tip for Mounting with Adapter
• How are the large mounting holes (counterbores) at the middle of a translation stage used?
• Is fast access to all mounting slots on a linear translation stage possible?

 

Design Elements of Thorlabs' Products

• Do translation stages isolate mounted components from vibrations transmitted through the adjuster?
• Post Holders: Rectangular Channel in the Inner Bore
• Bases: For Stability Orient the Side with the Undercut Down

 

Fiber Optics

• When does NA provide a good estimate of the fiber's acceptance angle?
• Why is MFD an important coupling parameter for single mode fibers?
• Does NA provide a good estimate of beam divergence from a single mode fiber?
• What factors affect the amount of light coupled into a single mode fiber?
• Is the max acceptance angle constant across the core of a multimode fiber?

 

Integrating Spheres

• Ultraviolet and Blue Fluorescence Emitted by Integrating Spheres
• Sample Substitution Errors

 

Lasers

• Are collimated beams always emitted parallel to the laser's axis?
• Quantum and Interband Cascade Lasers (QCLs and ICLs): Operating Limits and Thermal Rollover
• HeNe Lasers: Handling and Mounting Guidelines
• Beam Size Measurement Using a Chopper Wheel

 

Lens Mounts

• Can C-mount and CS-mount cameras and lenses be used with each other?
• Do Thorlabs' scientific cameras need an adapter? 
• Why can the FFD be smaller than the distance separating the camera's flange and sensor?

Motion Control

• How can a manual translation stage be motorized?
• Recording Position from Digital Micrometers

 

Off-Axis Parabolic (OAP) Mirrors

• Why use a parabolic mirror instead of a spherical mirror?
• Benefit of an Off-Axis Parabolic Mirror
• The Off-Axis Angle of an OAP Mirror
• Focus Collimated Light / Collimate Light from a Point Source Using an OAP Mirror
• Locating the Optical and Focal Axes of an OAP Mirror
• Paired OAP Mirrors Can Relay an Image and Make the Beam Accessible
• Mounting and Aligning an OAP Mirror
• Directionality of OAP-Mirror-Based Reflective Collimators

 

Optical Isolators and the Faraday Effect

• How can the strength of a material's Faraday effect be measured?

 

Photodiodes

• How does wavelength affect rise time?

 

Polarization-Maintaining (PM) Fiber

• Does PM fiber preserve every input polarization state?
• How does polarization-maintaining fiber preserve linearly polarized light?
• What limits the extinction ratio (ER) of light output from PANDA and bow-tie PM fibers?
• What is beat length and why is it often specified for PM fiber, instead of polarization extinction ratio?
• Are polarization-maintaining fibers with stress rods affected by operating temperature?

 

Polarized Light

• Labels Used to Identify Perpendicular and Parallel Components
• How is the polarization ellipse related to the polarization state?
• How is a Poincaré sphere useful for representing polarization states?

Reflective Elements

• Is there a rule for choosing the mirror's diameter based on the laser beam's diameter?
• How does alignment affect the beam path through a retroreflector?
• Why coat the backsides of solid prism retroreflectors with metal?
• Does the angle of incidence affect the output beam power from a corner-cube retroreflector?

Software and Writing Programs to Control Devices

• DM713 Digital Micrometer: LabVIEW and C# Programming References

 

Video Insights

• Align a Laser Beam Level to the Optical Table
• Optical Power Meter Parameter Setup for Improved Accuracy
• Mount a Translation Stage and Install a Motorized Actuator
• Avoid Screw-Length Pitfalls When Securing a Post Holder to a Table or Base
• Tune a Free-Space Faraday Isolator for Operation at the Laser Wavelength
• Align a Linear Polarizer's Axis to be Perpendicular or Parallel to the Table
• Cleave a Large-Diameter Silica Fiber Using a Hand-Held Scribe
• Create Circularly Polarized Light Using a Quarter-Wave Plate
• Align a Linear Polarizer 45° to the Plane of Incidence