Thorlabs' Polaris®KA Low-Distortion Kinematic Mirror Mounts provide long-term pointing stability while minimizing optic surface distortion introduced by the mount. 

• Matched Actuator and Body Pairs Minimize Drift and Backlash
• Heat Treating Minimizes Temperature-Dependent Hysteresis
• Face Mount Reduces Distortion of the Optic
• Lightweight Aluminum Front and Back Plates

Ø1/2" Polaris®KA Low-Distortion Kinematic Mounts, 3 Adjusters

• 3-Adjuster Low-Distortion Mounts Designed for Ø1/2" Optics
• Hex-Driven Design
• 100 TPI Matched Actuator / Body Pairs
• Low-Profile or Standard-Profile Adjusters
• Less Than 4 µrad Deviation After Temperature Cycling

These 3-adjuster Ø1/2" PolarisKA Kinematic Mirror Mounts use an integrated, aluminum matched adjuster/body design to minimize optic distortion and provide long-term stability. These mounts are equipped with a three-point-contact faceplate to mount the optic. The indexed optic retention spring makes contact with the optic at three locations, while the retaining ring has a calibrated adjustment stop to assist in providing the correct mounting torque.

Ø1/2" Polaris®KA Low-Distortion Kinematic Mount, 2 Adjusters

• 2-Adjuster Low-Distortion Mounts Designed for Ø1/2" Optics
• Hex-Driven Design
• 100 TPI Matched Actuator / Body Pairs
• Low-Profile or Standard-Profile Adjusters
• Less Than 4 µrad Deviation After Temperature Cycling 

These 2-adjuster Ø1/2" PolarisKA Kinematic Mirror Mounts are similar to the standard 3-adjuster versions sold above but feature a hardened steel ball in place of the third adjuster. They use an integrated, aluminum, matched adjuster/body design for greater durability than standard mirror mounts. 

This video provides an overview of the engineering involved in designing and manufacturing Thorlabs' Polaris Mounts. 

Features

• Machined from Aged 7075 Aluminum Alloy for Exceptional Tensile Strength, Stiffness, Surface Toughness, and Dimensional Stability
• Spring-Loaded, Indexed, Three-Point-Contact Plate Secures Optic
• Hardened Stainless Steel Ball Contacts with Sapphire Seats for Durability and Smooth Movement
• Matched Actuator and Body Pairs Provide Smooth Kinematic Adjustment
• Extensive Testing Guarantees Less than 4 µrad Deviation after Temperature Cycling 
• Specialty Anodized Frames and Passivated Stainless Steel Adjusters Designed for Vacuum and High-Power Laser Cavity Applications

Optic Retention

Each mount features a three-point-contact faceplate to mount the optic and reduce optical distortion compared to standard setscrew or retaining ring optic mount designs. An indexed retention spring between the optic and retaining ring eliminates bending moments on the optic and ensures the force on the optic remains constant over large temperature changes. 

Polaris optic bores are precision machined to achieve a fit that will provide optimum beam pointing stability performance over changing environmental conditions such as temperature changes, transportation shock, and vibration. Each mount is designed to be used with a Ø1/2" optic that is within +0/-0.005" of the specified diameter; using an optic outside of this range will lead to diminished performance. 

Cleanroom and Vacuum Compatibility

All of our PolarisKA mounts are designed to be compatible with cleanroom and vacuum applications and have maximum bake-out and operating temperatures of 80 °C. 

The aluminum front and back plates of PolarisKA mounts are acid etched, specialty anodized with a thin 5 µm oxide layer, and duplex sealed with nickel, followed by boiling in reverse osmosis deionized (RODI) water. This process creates an all-metal surface that is clean, smooth, thin, hard, non-porous, and has a sealed oxide layer. This same surface treatment is also used by some vacuum chamber manufacturers to prevent a native oxide layer from forming on the surface of bare aluminum. This surface finish provides an improvement over standard anodizing. For PolarisKA mounts, we recommend a maximum bake-out temperature of no more than 80 °C.