Adjustable SM1 Lens Tubes
High-Precision Zoom Housing
Non-Rotating Zoom Housing
Adjustable Ø1" Lens Tubes
Adjustable lens tubes allow for the adjustment of an optic's position within an SM lens tube system. The SM1V05, SM1V10, and SM1V15 provide rotating adjustment, while the SM1ZM, SM1NR1, and SM1NR05 zoom housings use helical drive mechanisms to provide linear travel of the internal cell without rotation. Unlike the other items on this page, the SM1V05, SM1V10, and SM1V15 must be combined with another SM1-threaded lens tube in order to provide adjustment. Finally, the SM1ZM and SM1NR1 can be combined with a standard SM1 lens tube to construct a non-rotating telescoping lens tube system.
SM1ZM Zoom Housing - Optic Alignment in a Confocal Microscope
Thorlabs' SM1ZM High-Precision Zoom Housing (denoted by 4 in the image below) is useful when precise Z-positioning of optics is necessary. In the following example of a partial confocal microscope, a light-tight connection can be created between a DFM1 Dichroic Filter Cube (1) containing a Microscopy Filter Set (2), and an APD120A2 Photodetector (8). A lens (5) located inside the SM1ZM Zoom Housing (4) focuses the beam onto a precision pinhole (7) located just before the avalanche photodetector's sensor. The SM1ZM zoom housing is mounted directly onto the ST1XY-D XY Translation Mount with Differential Adjusters (6), creating a compact XYZ mount. SM1 Lens Tubes and the SM1B3 Lens Tube Bellows (3) allow for a light-tight connection without inhibiting the free movement of the XYZ mount.
Thorlabs' Threading Specifications
Thorlabs' lens tubes utilize a series of non-standard threadings. Threading specifications are given below for our SM threadings utilized in our lens tube and cage system components so that you can machine mating components to suit your application. We also offer products with C-Mount and RMS threadings, and the specifications for these threadings are also given below. Please note that other manufacturers may have different tolerances for these threads. For other thread specifications that are not listed here, please contact Tech Support.
These SM1-threaded (1.035"-40) adjustable lens tubes have an extra-long externally threaded section, allowing Ø1" optics to be precisely positioned along the optical axis of a lens tube system. To operate, mount the optic in the internally threaded section using the included SM1RR retaining ring. Then thread the adjustable lens tube into a compatible SM1-threaded lens tube or lens mount until the optic is at the desired position. Use the included SM1NT locking ring to fix the position of the lens tube. See the video to the right for a demonstration.
For applications where it is difficult to reach the locking ring by hand, we offer the SM1NT1 Slotted Locking Ring and SPW502 Spanner Wrench. This locking ring contains slots for the 1¼" end of the spanner wrench.
These adjustable lens tubes are 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 has been fixed, since this lens tube will need to be free to rotate and translate if the position is changed. Like our standard lens tubes, these adjustable lens tubes are made of black anodized aluminum.
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Each Tick on the Engraved Scale Indicates 0.25 mm of Internal Translation
Click to Enlarge CP03 Cage Plate.
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A Standard SM1 Lens Tube can be Threaded to the Internal Translating Cell to Create a Telescoping Lens Tube Assembly
The SM1NR1 is an SM1-threaded, non-rotating zoom housing. It features an internal SM1-threaded (1.035"-40) translating cell for mounting Ø1" optics using the included SM1RR retaining ring, or for connecting SM1 lens tubes. A double-helical mechanism allows this cell to be translated along the optical axis without rotation (see video to the lower left). Each engraved tick mark on the rotating adjustment collar indicates 0.25 mm of linear travel of the inner cell (see photo to the far right). An 0.050" hex setscrew located by the Thorlabs engraving locks the movement, and tungsten disulfide dry film lubricant on the exposed internal surfaces ensures smooth translation.
The back of the housing includes an external SM1 thread for integration into lens tube systems. Additionally, the front of the housing includes a Ø1.38" (Ø35 mm) boss for 30 mm cage system integration using our CP03 cage plate (see photo above, to the immediate right).
Telescoping Lens Tube
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The SM1ZM non-rotating zoom housing provides 0.16" (4.1 mm) of linear travel without rotating the optical element mounted in it. A fine helical mechanism moves the front barrel back and forth while restricting any rotational movement, preventing any rotation of the attached lens tubes or optics (see image to the right). This high-precision (0.5 mm per revolution) zoom housing provides the ability to accurately control the exact working distance of an optical element within a system prior to locking it into place.
To operate, mount a Ø1" optic in the zoom housing and secure it using the included SM1RR retaining ring. Then attach the SM1ZM to an internally threaded SM1 lens tube or mount. Once secure, the outer ring of the SM1ZM can be used to precisely position the optic. A standard SM1 lens tube can also be attached to the front of the SM1ZM to create a telescoping lens tube assembly (see image to the right). For a more involved application within a confocal microscope setup, please see the Application tab.
The SM1NR05 non-rotating zoom housing provides 18 mm of linear travel without rotating the optical element mounted in it. A double helical mechanism moves the interior SM05 barrel back and forth while restricting any rotational movement. This 17 mm per revolution zoom housing provides the ability to accurately control the exact working distance of an optical element within a system. To operate, mount a Ø1/2" optic in the zoom housing and secure it using the included SM05RR retaining ring. Then the SM1NR05 can be mounted on any SM1 threaded lens tube or mount. Once secure, the outer ring of the SM1NR05 can be used to precisely position the optic.
Unlike the other lens tubes and housing on this page, the SM1NR05 offers fixed SM1 threading on both ends, allowing it to be attached between two fixed Ø1" lens tubes while still retaining the ability to adjust the position of the optic (see the video to the right).