Vacuum-Compatible Lens Tubes

Lens Tubes Mount Either Ø1/2" (12.7 mm) or Ø1" (25.4 mm) Optics
SM05- or SM1-Threading Standard Used Throughout Thorlabs' Product Line
Vented Design to Reduce Air Pockets Under Vacuum

SM05L03V

0.30" Thread Depth

SM1L03V

0.30" Thread Depth

SM1V05V

Adjustable Lens Tube,
0.81" Travel Range

SM1L10V

1.00" Thread Depth

Vents along the lens tube threading allow for air to easily pass mounted optics.

Item # Engraved Above External Threading

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Overview
Threading Specs
Feedback

Additional Vacuum-Compatible Components

Many of our other optomechanical components can be special ordered for vacuum use. Contact techsupport@thorlabs.com for details.

Vacuum Specifications
Vacuum Compatibility as Packaged^a	>10^-6 Torr
Materials	6061-T6 Aluminum
Preparation and Packaging	Chemically Cleaned and Double Vacuum-Bagged

This is the pressure at which these components can be used with no additional processing. They can be used at even lower pressures with additional cleaning and processing.

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Vents along the threading and at the ends of these tubes provide a free path for air to escape when under vacuum.

Features

SM05- (0.535"-40) and SM1- (1.035"-40) Threaded Lens Tubes
Stackable and Adjustable Versions
Compatible with SM05- or SM1-Threaded Vacuum Components
Lens Tubes Directly Accept Ø1/2" (Ø12.7 mm) or Ø1" (Ø25.4 mm) Optics

Lens Tubes are ideal for creating compact optical subassemblies with light-tight beam paths. The lens tubes sold here can be used to house one or several optical elements. The SM05-threaded lens tubes are designed for Ø1/2" optics, while our SM1-threaded lens tubes fit Ø1" optics. These vacuum-compatible lens tubes feature venting channels along their threading and at the ends of each tube that allow air trapped between mounted optics an easy means of escape during pumpdown.

We offer two varieties of vacuum-compatible lens tubes. Stackable lens tubes are designed to be threaded up against each other to create modular lens tube systems of fixed length. Adjustable lens tubes have extended external threading which allow the lens cell to be threaded back and forth along the optical axis at the end of a lens tube system and locked in place with an included locking ring.

Optics are secured and separated by vacuum-compatible retaining rings that are positioned along the length of the lens tube using a compatible spanner wrench, sold below. Each of the lens tubes on this page come with a compatible SM-threaded retaining ring.

In addition to the lens tubes featured on this page, Thorlabs also offers Ø1/2", Ø1", Ø30 mm, Ø1.5", Ø2", and Ø3" stackable lens tubes as well as Ø1/2", Ø1", Ø2", and Ø3" adjustable lens tubes for non-vacuum applications, each of which is equipped with an SM series thread standard that depends on the tube diameter (see the Threading Specs tab). Vacuum-compablitble, vented versions of these lens tubes can be ordered by contacting Tech Support.

Vacuum Compatibility Information
Our vacuum-compatible optomechanics are chemically cleaned and prepared for vacuum applications before packaging. They are compatible directly out of the packaging with vacuum environments down to 10^-6 Torr. With additional cleaning and processing, they can be used at even lower pressures, only limited by the outgassing rate of the aluminum. The material properties of the aluminum and the cleaning methods completed by the end user should be used to determine the appropriateness of these products and materials in a specific vacuum system.

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Threading Specifications

The following is a general overview of screw threading. For more details regarding specifications and dimensions, please consult the Machinery's Handbook, available for purchase at many bookstores.

Features of a Thread
A thread consists of three repeating features: a crest, flank, and root (see drawing to the right). Except in special cases, threads have symmetrical sides inclined at equal angles when a vertical line is drawn through the center of a crest or root. The distance between corresponding points on adjacent threads is known as the pitch of the thread. The flank angle is defined as the angle the flank makes with a perpendicular ray drawn from the screw axis. Unless otherwise stated, threads have a flank angle of 30°, resulting in a total angle between flanks of 60°. Each feature is shown in the diagram to the right.

The major diameter is taken from the crests of a thread while the minor diameter is taken from the roots. For most screws, crests and roots do not terminate at a sharp point, so crest and root truncation values are included in the definitions of major and minor diameter. The pitch diameter is approximately halfway between the major and minor diameters.

Thread Form
A thread form is a set of rules that define the features' scale relative to one another. Common thread forms include the Unified Screw Thread Form, used in the United States of America and measured in imperial units, and the ISO Metric Screw Thread Form, used in many parts of the world and measured with the International System of Units. There are many thread forms in the Unified screw thread standard designated by either UN, which defines a flat root contour, or UNR, which defines a round root contour. These can be further described by appending more letters. For example, an extremely fine thread with a flat root contour is designated UNEF. Those forms which are not standardized by the Unified screw thread system are designated UNS.

Thread Series
Most screws are identified by their thread series. Thread series are denoted by the major diameter and density of threads. Unified threads specify density in threads per inch, while Metric threads specify the thread pitch. For example, in the Unified nomenclature, a 1/4"-20 cap screw has a 1/4" diameter barrel and the pitch is 20 threads per inch (TPI). In metric nomenclature, an M4 x 0.7 cap screw has a 4 mm barrel and the pitch is 1 thread per 0.7 mm. The term M4 x 0.7 is often shortened to just M4.

Unified Thread Class Tolerancing
Location	Loose	Optimal	Strict
Internal	1B	2B	3B
External	1A	2A	3A

Metric Thread Tolerance Positions
Location	Loose	Optimal	Strict
Internal	-	G	H
External	e or f	g	h

Metric Thread Tolerance Grades
Dimension	Location	Tolerance Grades^a
Minor Diameter	Internal	4, 5, 6, 7, 8
Major Diameter	External	4, 6, 8
Pitch Diameter	Internal	4, 5, 6, 7, 8
Pitch Diameter	External	3, 4, 5, 6, 7, 8, 9

The tolerance becomes looser as the grade increases. The underlined grades are used with normal lengths of thread engagement.

Thread Class
The tolerances and allowances on a thread series are given by a thread class. Unified thread classes are alphanumeric identifiers starting with a number from 1 through 3, where 1 is the loosest tolerance and 3 is the tightest, and either A for external threading or B for internal threading.

Metric threads have a slightly more complex tolerancing method that uses tolerancing grades, designated by a number 3 through 9; and tolerancing positions, which use letters e through h. Grades provide a measure of the tolerance itself: the smaller the number, the tighter the tolerance. Positions denote the distance of the tolerance from the pitch diameter. Uppercase positioning letters indicate internal threads while lowercase positioning letters indicate external threads.

Quoting from the Machinery's Handbook, 29th Edition, p. 1885: "To designate the tolerance class, the grade and position of the pitch diameter is shown first followed by that for the major diameter in the case of the external thread or that for the minor diameter in the case of the internal thread, thus 4g6g for an external thread and 5H6H for an internal thread. If the two grades and positions are identical, it is not necessary to repeat the symbols, thus 4g, alone, stands for 4g4g and 5H, alone, stands for 5H5H."

Thorlabs' SM Series Threads
Threading specifications for our SM threads, utilized in our lens tube and cage system components, are given below so that you can machine mating components to suit your application. Most SM series threads utilize a non-standard Unified thread form, indicated by the letters UNS, with a 30° flank angle and a thread class of 2A and 2B. The exception is our SM30 series thread, which is a Metric thread form with a 30° flank angle and a tolerance of 6H/6g. We also offer products with C-Mount and RMS threads, and the specifications for these threads are given below for reference. Please note that other manufacturers may have different tolerances for C-Mount and RMS threads. For other thread specifications that are not listed here, please contact Tech Support.

SM05 Threading: Ø1/2" Lens Tubes, 16 mm Cage Systems
External Thread, 0.535"-40.0 UNS-2A		Internal Thread, 0.535"-40.0 UNS-2B
Max Major Diameter	0.5340"	Min Major Diameter	0.5350"
Min Major Diameter	0.5289"	Min Pitch Diameter	0.5188"
Max Pitch Diameter	0.5178"	Max Pitch Diameter	0.5230"
Min Pitch Diameter	0.5146"	Min Minor Diameter (and 83.3% of Thread)	0.508"
Max Minor Diameter	0.5069"	Max Minor Diameter (and 64.9% of Thread)	0.514"

RMS Threading: Objective, Scan, and Tube Lenses
External Thread, 0.800"-36.0 UNS-2A		Internal Thread, 0.800"-36.0 UNS-2B
Max Major Diameter	0.7989"	Min Major Diameter	0.8000"
Min Major Diameter	0.7934"	Min Pitch Diameter	0.7820"
Max Pitch Diameter	0.7809"	Max Pitch Diameter	0.7866"
Min Pitch Diameter	0.7774"	Min Minor Diameter (and 83.3% of Thread)	0.770"
Max Minor Diameter	0.7688"	Max Minor Diameter (and 64.9% of Thread)	0.777"

C-Mount Threading: Machine Vision Lenses, CCD/CMOS Cameras
External Thread, 1.000"-32.0 UN-2A		Internal Thread, 1.000"-32.0 UN-2B
Max Major Diameter	0.9989"	Min Major Diameter	1.0000"
Min Major Diameter	0.9929"	Min Pitch Diameter	0.9797"
Max Pitch Diameter	0.9786"	Max Pitch Diameter	0.9846"
Min Pitch Diameter	0.9748"	Min Minor Diameter (and 83.3% of Thread)	0.966"
Max Minor Diameter	0.9651"	Max Minor Diameter (and 64.9% of Thread)	0.974"

SM1 Threading: Ø1" Lens Tubes, 30 mm Cage Systems
External Thread, 1.035"-40.0 UNS-2A		Internal Thread, 1.035"-40.0 UNS-2B
Max Major Diameter	1.0339"	Min Major Diameter	1.0350"
Min Major Diameter	1.0288"	Min Pitch Diameter	1.0188"
Max Pitch Diameter	1.0177"	Max Pitch Diameter	1.0234"
Min Pitch Diameter	1.0142"	Min Minor Diameter (and 83.3% of Thread)	1.008"
Max Minor Diameter	1.0068"	Max Minor Diameter (and 64.9% of Thread)	1.014"

SM30 Threading: Ø30 mm Lens Tubes
External Thread, M30.5 x 0.5 – 6H/6g		Internal Thread, M30.5 x 0.5 – 6H/6g
Max Major Diameter	30.480 mm	Min Major Diameter	30.500 mm
Min Major Diameter	30.371 mm	Min Pitch Diameter	30.175 mm
Max Pitch Diameter	30.155 mm	Max Pitch Diameter	30.302 mm
Min Pitch Diameter	30.059 mm	Min Minor Diameter (and 83.3% of Thread)	29.959 mm
Max Minor Diameter	29.938 mm	Max Minor Diameter (and 64.9% of Thread)	30.094 mm

SM1.5 Threading: Ø1.5" Lens Tubes
External Thread, 1.535"-40 UNS-2A		Internal Thread, 1.535"-40 UNS-2B
Max Major Diameter	1.5339"	Min Major Diameter	1.535"
Min Major Diameter	1.5288"	Min Pitch Diameter	1.5188"
Max Pitch Diameter	1.5177"	Max Pitch Diameter	1.5236"
Min Pitch Diameter	1.5140"	Min Minor Diameter (and 83.3% of Thread)	1.508"
Max Minor Diameter	1.5068"	Max Minor Diameter (and 64.9% of Thread)	1.514"

SM2 Threading: Ø2" Lens Tubes, 60 mm Cage Systems
External Thread, 2.035"-40.0 UNS-2A		Internal Thread, 2.035"-40.0 UNS-2B
Max Major Diameter	2.0338"	Min Major Diameter	2.0350"
Min Major Diameter	2.0287"	Min Pitch Diameter	2.0188"
Max Pitch Diameter	2.0176"	Max Pitch Diameter	2.0239"
Min Pitch Diameter	2.0137"	Min Minor Diameter (and 83.3% of Thread)	2.008"
Max Minor Diameter	2.0067"	Max Minor Diameter (and 64.9% of Thread)	2.014"

SM3 Threading: Ø3" Lens Tubes
External Thread, 3.035"-40.0 UNS-2A		Internal Thread, 3.035"-40.0 UNS-2B
Max Major Diameter	3.0337"	Min Major Diameter	3.0350"
Min Major Diameter	3.0286"	Min Pitch Diameter	3.0188"
Max Pitch Diameter	3.0175"	Max Pitch Diameter	3.0242"
Min Pitch Diameter	3.0133"	Min Minor Diameter (and 83.3% of Thread)	3.008"
Max Minor Diameter	3.0066"	Max Minor Diameter (and 64.9% of Thread)	3.014"

SM4 Threading: Ø4" Lens Tubes
External Thread, 4.035"-40 UNS-2A		Internal Thread, 4.035"-40.0 UNS-2B
Max Major Diameter	4.0337"	Min Major Diameter	4.0350"
Min Major Diameter	4.0286"	Min Pitch Diameter	4.0188"
Max Pitch Diameter	4.0175"	Max Pitch Diameter	4.0245"
Min Pitch Diameter	4.0131"	Min Minor Diameter (and 83.3% of Thread)	4.008"
Max Minor Diameter	4.0066"	Max Minor Diameter (and 64.9% of Thread)	4.014"

Posted Comments:

Iain Wilkinson (posted 2022-03-17 13:20:52.907)

I need the equivalent of the SM1L05V lens tube for a 2" rather than 1" outer diameter optic. Do you have any plans to produce this?

jdelia (posted 2022-03-17 02:54:12.0)

Thank you for contacting Thorlabs. While we do not offer 2" vacuum lens tubes as a stock part, I can certainly pass along your feedback to our internal suggestion forum. In the meantime, we are contacting you directly to discuss quoting these out as a custom part.

geoffrey Rhoads (posted 2020-08-27 11:15:04.17)

I submitted an earlier feedback and it said my security code entered was invalid, then it all just went away. I hope you got it!

llamb (posted 2020-09-01 08:16:34.0)

Thank you for contacting Thorlabs. I have reached out to you by email directly to discuss your feedback and application.

SM05-Threaded Vacuum-Compatible Stackable Lens Tubes

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Stackable Design Enables Multi-Element Optical Systems
Accepts Ø1/2" (12.7 mm) Optics
SM05-Threaded (0.535"-40) Bore
0.30", 0.50", and 1.00" Internal Thread Depths Available

These Ø1/2" lens tubes, with their stackable design and ability to interface with other SM05-threaded components, can be used to house compact optical assemblies or as a building block in complex optomechanical systems. Made from 6061-T6 aluminum, these vented lens tubes are vacuum compatible down to 10^-6 Torr. One SM05RRV vacuum-compatible retaining ring is included with each lens tube.

Item #	L	Internal Thread Depth
SM05L03V	0.33" (8.4 mm)	0.30" (7.6 mm)
SM05L05V	0.53" (13.5 mm)	0.50" (12.7 mm)
SM05L10V	1.03" (26.2 mm)	1.00" (25.4 mm)

Non-Vacuum-Compatible Alternatives	Ø1/2", Ø1", Ø30 mm, Ø1.5", Ø2", and Ø3" Stackable Lens Tubes

SM05-Threaded Vacuum-Compatible Adjustable Lens Tube

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SM05V05 Adjustable Lens Tube Mechanical Drawing

Click for Details
A_min and A_max are the minimum and maximum distances another lens tube can be positioned from the back of the lens cell when using the locking ring.

Long Externally Threaded Section for Adjustable Positioning of Mounted Optics
Adjustment Range of 0.31" (7.9 mm)
Accepts Ø1/2" (Ø12.7 mm) Optics up to 0.43" (11.0 mm) Thick
One SM05RRV Retaining Ring and SM05NT1V Locking Ring Included

This Ø1/2" vacuum-compatible adjustable lens tube allows optics to be precisely positioned along the optical axis of a lens tube system. Made from 6061-T6 aluminum, these vented lens tubes are vacuum compatible down to 10^-6 Torr.

To operate, mount the optic in the internally threaded section using the included SM05RRV retaining ring. Then thread the adjustable lens tube into a compatible SM05-threaded lens tube until the optic is at the desired position. At this point, the included SM05NT1V Slotted Locking Ring can be used to fix the position of the lens tube. See the video to the right for a demonstration. This locking ring contains slots for the 3/4" end of the SPW502 Spanner Wrench.

This rotating adjustable lens tube is an ideal solution for fine tuning of the first and last lenses in a lens tube system. Although a lens tube can be attached to the front of the adjustable lens tube, it should only be done after the position of the optic has been fixed, since this lens tube will need to be free to rotate and translate if the position of the optic is changed.

Item #	External Thread Length (L)	Adjustment Range (A_min to A_max)^a
SM05V05V	0.5" (12.7 mm)	0.11" - 0.42" (2.8 mm - 10.7 mm)

A_min includes the thickness of the included locking ring, while A_max accounts for the minimum 0.08" (2 mm) thread depth needed to engage the attached lens tube or component.

Non-Vacuum-Compatible Alternatives	Ø1/2", Ø1", Ø2", and Ø3" Adjustable Lens Tubes

SM1-Threaded Vacuum-Compatible Stackable Lens Tubes

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Stackable Design Enables Multi-Element Optical Systems
Accepts Ø1" (Ø25.4 mm) Optics
SM1-Threaded (1.035"-40) Bore
0.30", 0.50", and 1.00" Internal Thread Depths Available

These Ø1" lens tubes, with their stackable design and ability to interface with other SM1-threaded components, can be used to house compact optical assemblies or as a building block in complex optomechanical systems. Made from 6061-T6 aluminum, these vented lens tubes are vacuum compatible down to 10^-6 Torr. One SM1RRV vacuum-compatible retaining ring is included with each lens tube.

Item #	L	Internal Thread Depth
SM1L03	0.33" (8.4 mm)	0.30" (7.6 mm)
SM1L05	0.53" (13.5 mm)	0.50" (12.7 mm)
SM1L10	1.03" (26.2 mm)	1.00" (25.4 mm)

Non-Vacuum-Compatible Alternatives	Ø1/2", Ø1", Ø30 mm, Ø1.5", Ø2", and Ø3" Stackable Lens Tubes

SM1-Threaded Vacuum-Compatible Adjustable Lens Tube

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Adjustable Lens Tube Usage

Click for Details
A_min and A_max are the minimum and maximum distances another lens tube can be positioned from the back of the lens cell when using the locking ring.

Long Externally Threaded Section for Adjustable Positioning of Mounted Optics
Adjustment Range of 0.81" (20.6 mm)
Accepts Ø1" (Ø25.4 mm) Optics up to 0.42" (10.7 mm) Thick
One SM1RRV Retaining Ring and SM1NT1V Locking Ring Included

This Ø1" vacuum-compatible adjustable lens tube allows optics to be precisely positioned along the optical axis of a lens tube system. Made from 6061-T6 aluminum, these vented lens tubes are vacuum compatible down to 10^-6 Torr.

To operate, mount the optic in the internally threaded section using the included SM1RRV retaining ring. Then thread the adjustable lens tube into a compatible SM1-threaded lens tube until the optic is at the desired position. At this point, the included SM1NT1V Slotted Locking Ring can be used to fix the position of the lens tube. See the video to the right for a demonstration. This locking ring contains slots for the 1¼" end of the SPW502 Spanner Wrench.

Item #	External Thread Length (L)	Adjustment Range (A_min to A_max)^a
SM1V10V	1.0" (25.4 mm)	0.11" - 0.92" (2.8 mm - 23.4 mm)

A_min includes the thickness of the included locking ring, while A_max accounts for the minimum 0.08" (2 mm) thread depth needed to engage the attached lens tube or component.

Non-Vacuum-Compatible Alternatives	Ø1/2", Ø1", Ø2", and Ø3" Adjustable Lens Tubes

Spanner Wrenches and Vacuum-Compatible Retaining Rings

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Vacuum-Compatible Retaining Rings for Securing Either Ø1/2" or Ø1" Optics
Spanner Wrenches Provide One-Handed Adjustment of Retaining Rings
SPW801 Adjustable Spanner Wrench can Accommodate Diameters from 0.12" (3.0 mm) to 2.89" (73.4 mm)

Thorlabs offers vacuum-compatible retaining rings for use with aluminum vacuum-compatible components. SM05RRV retaining rings are for securing Ø1/2" optics in SM05-threaded (0.535"-40) components, and SM1RRV retaining rings are for securing Ø1" optics in SM1-threaded (1.035"-40) components. Each 6061-T6 aluminum ring is shipped double-vacuum bagged and is vacuum compatible to 10^-6 Torr.

To secure these retaining rings, we offer several spanner wrenchs. The SPW603 and SPW606 spanner wrenches are 1" long and can adjust SM05- and SM1-threaded retaining rings, respectively. The SPW603L and SPW602 spanner wrenches are built for SM05- and SM1-threaded retaining rings, respectively, and their 3.88" long bodies include a graduated scale to help seat rings at a repeatable depth in a lens tube. The SPW801 adjustable spanner wrench can be resized for retaining rings as large as the SM3RR for Ø3" components. We also offer the SPB05 SM05 and SPB1 SM1 Spanner Bits, which can be used with a standard 1/4" hex driver (sold separately). The both bits are included as part of the SPB600 Spanner Wrench Bit Kit. Note that our spanner wrenches are neither rated for vacuum compatibility nor prepared for cleanroom use.

Based on your currency / country selection, your order will ship from Newton, New Jersey

+1 Qty Docs Part Number - Universal Price Available

SM05RRV Customer Inspired! Unanodized Aluminum SM05 Retaining Ring for Ø1/2" Lens Tubes and Mounts

$12.01

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SM1RRV Customer Inspired! Unanodized Aluminum SM1 Retaining Ring for Ø1" Lens Tubes and Mounts

$12.01

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SPW603 Spanner Wrench for SM05-Threaded Retaining Rings, Length = 1.00"

$28.54

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SPW603L Customer Inspired! Spanner Wrench for SM05-Threaded Retaining Rings, Graduated Scale with 0.02" (0.5 mm) Increments, Length = 3.88"

$65.87

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SPW606 Customer Inspired! Spanner Wrench for SM1-Threaded Retaining Rings, Length = 1.00"

$31.15

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SPW602 Spanner Wrench for SM1-Threaded Retaining Rings, Graduated Scale with 0.02" (0.5 mm) Increments, Length = 3.88"

$31.15

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SPW801 Adjustable Spanner Wrench

$114.14

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SPW102 Adjustable Spanner Wrench, Replacement Blade Set

$33.20

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Spanner Wrenches and Vacuum-Compatible Locking Rings

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Vacuum-Compatible Locking Rings for Securing Adjustable Lens Tubes
Available with either Internal SM05- or SM1-Threading
Spanner Wrench Provides One-Handed Adjustment of Locking Rings

Thorlabs offers vacuum-compatible locking rings for use with aluminum vacuum-compatible adjustable lens tubes. Their lack of anodization and 6061-T6 alumimun construction allows them to be used at vacuum levels down to 10^-6 Torr. Each ring is double vacuum-bagged for clean room use. These locking rings are knurled to allow hand tightening. For applications where it is difficult to reach the locking ring by hand, each locking ring contains slots for an end of the SPW502 Spanner Wrench. This spanner wrench is 6.10" (154.9 mm) long and can adjust both SM05- and SM1-threaded locking rings.