Fixed Lens Mounts
This page features Thorlabs' numerous options for mounting lenses in fixed mounts. Traditional fixed optic mounts (LMR series) are available for 13 discrete optic diameters ranging from Ø1/2" to Ø4", feature internal threading, and come complete with one retaining ring for securing the optic in place. Alternatively, if your application could benefit from a mount that has both internal an external SM threads, choose a member of our LMRxxS series. In either case, the fixed mount features an 8-32 (M4) tapped hole for post mounting. For small optics (i.e., less than Ø10 mm), we offer stainless steel adapters that allow these optics to be mounted in either our SM05-threaded or SM18-threaded mounts. We also offer a line of small optic adapters with external SM1 threading, which can mount optics from Ø5 mm to Ø20 mm in SM1-threaded lens mounts.
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Fixed Lens Mounts Feature Internal Threads and a Retaining Lip (LMR Series, Left), Internal and External Threads (LMRS Series, Center), or Internal Threads (SMR Series, Right)
LMR2 Ø2" Mount
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LMRA Series Adapters for Mounting Small Optics
Fixed Optic Mounts with Internal Threads (LMR Series)
Fixed Optic Mounts with Internal and External Threads (LMRS Series)
Fixed Lens Mounts with Internal Threads and No Retaining Lip (SMR Series)
Mounting Small Optics (Ø5 mm to Ø10 mm)
Lens Mount Alignment Plates
LA1116 Lens epoxied into an LMRA6 Adapter using NOA61 Epoxy; the mounted lens was then placed in an LMR05 Mount
The optic adapter is designed to allow the lens to be epoxied into place (NOA61 epoxy recommended); simply place a drop or two of epoxy into each of the epoxy reservoirs in the adapter. Once the optic is secured in the adapter, the new assembly can be held in our LMR05 (LMR18 for LMRA10) mount with the included SM05RR (SM18RR) Retaining Ring.
These fixed lens mounts, which feature internal SM threading on one side and external SM threading on the other, are available for Ø1/2", Ø1", and Ø2" optics. The optic is secured in the mount with the included retaining ring and can be post mounted to a Ø1/2" Post.
The internal threading is deep enough to hold most unmounted optics, while the external threading is just deep enough to allow for the mounting of lens tubes, irises, or other internally threaded SM components (see picture to the right). Although the functionality of this part can be duplicated by combining two other Thorlabs parts, a lens tube slip ring and a lens tube, these fixed mounts offer significant price reduction, increased convenience, and smaller package size.
These SM05, SM1, or SM2-threaded mounting rings feature internal SM threading that extends the full length of the mount without any retaining lip. They are perfect for mounting lens tubes and other mounted optics, and can also be used to hold unmounted optics when used with two retaining rings (sold separately below).
These alignment targets can be quickly and easily dropped onto one of our fixed lens holder or lens tubes allowing the user to align a visible beam, using the center Ø1 mm through hole. Once the beam is aligned, the tool can be lifted from the lens holder or lens tube without disturbing the alignment and can later be replaced into approximately the same position.
For optimal visual alignment of the beam, both plates feature laser-engraved concentric circles, with the diameter of each circle being 2 mm greater than the previous. The LMR1AP alignment plate has eight of these concentric circles and fits Ø1" fixed optics mounts and lens tubes, while the LMR2AP alignment plate has twelve concentric circles and fits Ø2" fixed optics mounts and lens tubes.
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The SPW603 Spanner Wrench for SM05 Lens Tubes Interconnects to Reach the Retaining Rings in Long Lens Tubes
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SPW602 Spanner Wrench with Exposed Graduations
The hollow construction of these spanner wrenches allows SM-series retaining rings to be installed or adjusted without obscuring the beam path. They include guide flanges that prevent most optical surfaces from being scratched while the wrench is being inserted, and knurled handles that provide improved grip.
As shown to the right, the SPW602 additionally features an engraved depth scale with imperial and metric increments (0.02" and 0.5 mm, respectively), thereby enabling precise positioning of optics.
For retaining rings not covered by our standard spanner wrenches, please see the SPW801 Adjustable Spanner Wrench sold at the bottom of the page. The long blades on the SPW801 also prevent scratches caused by the guide flanges on lenses with high curvature.
Thorlabs' Adjustable Spanner Wrench features a spanning range that is continuously adjustable from 0.12" to 2.89" (3.0 mm to 73.4 mm). It is capable of providing an exact fit for SM-series retaining rings as large as the SM3RR for Ø3" Lens Tubes and Mounts. The diameter spanned by the blades remains centered while the knurled knob is adjusted.
The reversible blades have a flat tip on one end intended for use with retaining rings, and an edge-offset fine point on the opposing end for adapters with holes. The blades extend 1.6" (40.7 mm) from the body of the wrench, helping to avoid scratching of short-focal-length lenses caused by the guide flanges on our standard spanner wrenches. To reverse the blades, a 0.050" (1.3 mm) balldriver or hex key is needed. Replacement blade pairs are available separately.
The SPW801 wrench withstands a maximum torque of 80 inch-pounds (9 N·m).