Thorlabs offers these Ø2" adapters for unmounted optics to easily integrate various optic diameter standards into Ø2" optomechanical systems, including optic mounts and lens tubes (see the Selection Guide to the right). The unthreaded adapters presented here are double-bored to provide 2 lines of mounting contact for Ø1", Ø30 mm, or Ø1.5" optics. Our externally SM2- (2.035"-40) threaded adapters with internally threaded central bores can house optics ranging from Ø30 mm to Ø48 mm. A Ø2" adapter with internal SM1 (1.053"-40) threading for Ø1" optics and an externally SM2-threaded adapter with a smooth central bore for Ø1.5" optics are also available.
These unthreaded adapters feature a smooth Ø2" outer surface and a double-bored counterbore to provide two lines of mounting contact. The counterbores in the AD2, AD2-30, and AD2-1.5 are Ø1", ØØ30 mm and Ø1.5", respectively. Optics are secured against the two contact lines using a nylon-tipped setscrew.
Optic Thickness (Max)b
Ø1.00" (Ø25.4 mm)
0.22" (5.6 mm)
0.25" (6.4 mm)
Ø30 mm (Ø1.18")
0.22" (5.6 mm)
0.25" (6.4 mm)
Ø1.51" (Ø38 mm)
0.27" (6.9 mm)
0.33" (8.4 mm)
This specification is true for thin lenses. For lenses with short focal lengths, and hence large lens curvatures, please contact technical support to ensure a proper fit.
Thickness of the adapter. See the drawing to the upper right.
Unthreaded Mounting Adapter: Ø2" Housing Ø1" Offset Close Approach Bore
The AD2-CA is designed with a 2" outer diameter and dual Ø1" internal bores. Please note that only one internal bore is meant for mounting the optic, which is held in place with an 8-32 nylon-tipped setscrew. This adapter enables separation of closely spaced beams with Ø1" circular optical components and is ideal for applications that require a narrow-angle back reflection. If you wish to mount one of our D-shaped mirrors, we recommend using one of our D-shaped mirror mounts.
The AD2T Adapter features internal SM1 threading and is designed to hold a Ø1" unmounted optic up to 0.37" (9.4 mm) thick with the included SM1RR retaining ring.b Alternatively, retaining rings can be used to hold this adapter in an SM2 lens tube. With a smooth outer diameter, the AD2T is especially well suited for mounting Ø1" wave plates into Ø2" mounts.
The SM2B2 features external SM2 threads and a Ø1.5" bore through the length of the part. A 4-40 setscrew secures Ø1.5" objects and allows them to be mounted in our SM2 Lens Tubes and SM2-compatible mounts. The SM2B2 adapter is designed to mount many of Thorlabs' isolators into SM2-threaded components.
Optic Thickness (Max)
The SM2B2 has a Ø1.5" bore through the length of the part, so the thickness of the mounted object is not limited.
Mounting Adapters with Internal and External Threads
These externally SM2-threaded adapters are designed to mount optics between Ø30 mm and Ø48 mm in internally SM2-threaded components, such as our Ø2" Lens Tubes or Ø2" Optic Mounts. Each mount features external SM2 threads and an internally threaded central bore (see the table below for thread specifications). Two retaining rings are included for securing optics in the adapter.