Kinematic Mirror Mount with a Detachable Front Plate

  • Detachable Kinematic Front Plate Accepts Ø1" Optics
  • Rare Earth Magnets Provide Sufficient Coupling Force
  • Repeatability Better than 15 µrad


#8 (M4) Counterbore Mounting Holes

Rare Earth Magnets


Additional Plates for KS1R

Related Items

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  • Detachable Kinematic Front Plate
  • Front Plate Magnetically Coupled to the Back Plate with Four Pairs of Rare Earth Magnets
  • Repeatability Better than 15 μrad
  • Mounts in Left-Handed or Right-Handed Orientation
  • Fabricated from Black Anodized Aluminum

Combining the functionality of our popular kinematic base plates with our versatile kinematic mirror mounts, the KS1R offers a unique solution for multi-path beam steering. The detachable front plate is held off the back plate with three 0.85" (21.6 mm) long, 1/4"- 80 lockable fine-adjustment screws, allowing multiple plates to be individually adjusted with respect to a common base plate. The optic is held in place with a nylon-tipped set screw. All of the mount's hex sockets accept a 5/64" (2 mm) ball driver or hex key, simplifying setup. Additionally, the actuator screws may be adjusted using a HKTS-5/64 hex adjuster. Four pairs of rare earth magnets provide the coupling force between the front and rear plates.

Each KS1R consists of one base plate and one KS1RF kinematic front plate. Additional KS1RF front plates can be purchased separately. Individual front plates can each be set with a different optic and adjusted for specific positioning requirements. Each aligned and mounted optic can then be easily swapped in and out without realigning the system.

Posted Comments:
Aidan Brooks  (posted 2021-09-09 14:52:51.227)
Dear Thorlabs, How much would it be to do a 2" version of the KS1R mount? Many thanks, Aidan Brooks.
YLohia  (posted 2021-09-09 03:37:39.0)
Hello, custom parts can be requested by emailing We will discuss the possibility of offering this customization directly.
Philipp Hanke  (posted 2020-12-01 10:26:44.127)
Is there an equal solution for 2'' optics? Best regards Philipp
YLohia  (posted 2020-12-02 10:14:31.0)
Hello Philipp, unfortunately, we don't offer a 2" version of this at the moment. The being said, you could use the components on this page ( and post-mount on a pitch/yaw stage for the same functionality.
laurent Milord  (posted 2019-09-11 06:18:59.133)
Hello, I can not reach the 15µrad repetability. I place the KSR1; I adjust the tip tilt to have auto-collimation of a laser using a mirror. I remove and replace the plate and got a deviation up to 38 mrad !! The mechanical stability is not good at all. Please contact me so we can figure the problem. Thank you, Laurent
YLohia  (posted 2019-09-30 08:41:23.0)
Hello Laurent, thank you for contacting Thorlabs. Based on our direct correspondence, it appears that this repeatability issue is caused by the one of the magnets having been popped out of place.
user  (posted 2014-09-09 04:34:56.467)
How long is the hex adjustment screw? Thank you.
sharrell  (posted 2014-09-10 08:27:28.0)
Response from Sean at Thorlabs: The hex adjustment screws are 0.85" (21.6 mm) long. This information can be found on the pdf drawing of the KS1RF pdf drawing, but I will add it to the text of the webpage as well.
andreas.brand  (posted 2013-03-08 18:10:45.797)
Hi, does this come with metrix hex screws? kind regards Andreas
jlow  (posted 2013-03-12 16:32:00.0)
Response from Jeremy at Thorlabs: The KS1R comes with hex adjustment screws that uses 5/64" hex key.
ted.borger  (posted 2012-10-26 15:11:55.967)
It would be much more useful for me if the KS1R had the adjustors with knobs, possibly in the non optic side in a more traditional setup.
tcohen  (posted 2012-11-07 21:26:00.0)
Response from Tim at Thorlabs: Thank you for your feedback. By keeping the actuators on the front plate, we are able to have kinematic adjustment for different optics and attach multiple plates to the same fixed back plate. We can offer knobs or alternatively an item that has a 5/64 hex key fixed to a removable knob. I will contact you to discuss this further.
daviet  (posted 2011-12-13 17:58:25.0)
Hi, My name is Alex, i work for a company called NT-MDT, based in Ireland, we're designing scanning probes microscopes. We are currently designing a new unit using a laser and we would be very interested in using some your prodcuts, for example the KS1R or 12031-E0W. When i am trying to download a step file or solidwork file, the dimensions are not matching the pdf file, especially the mounting holes. Would it be possible from your side to send me on the correct 3D file? Please do not hesitate to contact me by e-mail address at or by phone at +353 (0) 61 33 33 22. Hope to hear form you soon. Best regards, Alex.
bdada  (posted 2011-12-14 11:12:00.0)
Response from Buki at Thorlabs: Thank you for informing us of the inconsistencies in the model. We will upload a revised version to our website and send you a copy. Thank you again for your feedback.
Based on your currency / country selection, your order will ship from Newton, New Jersey  
+1 Qty Docs Part Number - Universal Price Available
KS1R Support Documentation
KS1RKinematic Mount with Removable Front Plate
Lead Time
KS1RF Support Documentation
KS1RFExtra Front Plate for KS1R Kinematic Mount