"; _cf_contextpath=""; _cf_ajaxscriptsrc="/cfthorscripts/ajax"; _cf_jsonprefix='//'; _cf_websocket_port=8578; _cf_flash_policy_port=1244; _cf_clientid='88292A265171AA9FF8761FBDCDF96BF8';/* ]]> */
| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
C-Mount Extension Tubes and Spacer Rings![]() CML05 CS- to C-Mount Adapter
CMRR C-Mount Retaining Ring
Application Idea CML25 Extension Tube Between a Machine Vision Lens and a 1500M-CL Scientific Camera CMSP150 1.50 mm Spacer Ring CMSP100 Spacer Ring Between CML100 and CML15 Extension Tubes ![]() Please Wait ![]() Click to Enlarge The introduction of an extension tube or spacer ring between a camera and a lens decreases the object distance and increases the image distance. Features
The C-Mount extension tubes and spacer rings sold here are designed to be used as spacers with C-Mount and CS-Mount instruments such as Thorlabs' CCD/CMOS cameras and camera lenses. These extension tubes or spacers increase the image distance between the lens and the camera sensor. This allows the lens to focus on objects at shorter distances than would be possible without a spacer. The decreased object distance increases the magnification of the image on the camera sensor while decreasing the depth of field. We offer C-Mount extension tubes in lengths from 5 mm to 100 mm for coarse adjustments of an optical system's length. We also offer adjustable extension tubes for continuous adjustment up to 0.81" (20.6 mm). In addition, brass spacer rings that fit over external C-Mount threads are available in thicknesses from 0.25 mm (0.01") to 2.00 mm (0.08"). These rings fit between two C-Mount components and provide fine spacing adjustments. The 1.20" (30.5 mm) outer diameter of the C-Mount extension tubes is the same as that of Thorlabs' Ø1" lens tubes, so the C-Mount tubes are compatible with all clamps and slip rings for Ø1" lens tubes. However, the 0.97" (24.6 mm) inner diameter of the C-Mount tubes is too small to accept Ø1" (Ø25.4 mm) or Ø25 mm (Ø0.98") optics. Non-standard optics with diameters between 0.87" (22.0 mm) and 0.97" (24.6 mm) can be secured inside the tubes with C-Mount retaining rings. For the construction of optical systems, Thorlabs offers lens tubes that accept Ø1/2", Ø1", Ø30 mm, Ø2", or Ø3" optics, each of which is equipped with an SM thread standard that depends on the tube diameter. We also offer extension tube and spacer ring kits, which contain a variety of thicknesses/lengths to allow for fine/coarse adjustment of the image distance without having to search for a single piece to provide the right distance. When used to image objects within the range of specified object distances, Thorlabs' camera lenses are designed to correct for optical aberrations. The modification of the specified object distance with extension tubes and spacer rings may reduce the ability of these lenses to eliminate aberrations. Please refer to the Object Distances tab for more details.
Thorlabs' Camera Lenses for Machine Vision each have a characteristic range of object distances. Objects placed within this range can be brought to a sharp focus on the sensor of the C-Mount camera. As seen in the image sequence below, the addition of an extension tube between the camera and the lens changes this range of object distances and allows the system to focus on objects closer to the lens. This increases the magnification of the image on the camera while decreasing the depth of field. The following table lists the range of possible object distances for various combinations of Thorlabs' C-Mount extension tubes and machine vision lenses. Note that Thorlabs' camera lenses are designed to correct for optical aberrations witin a specified range of object distances. The modification of the specified minimum object distance with an extension tube may reduce the ability of these lenses to eliminate aberrations. 5/8" (16 mm) Object Distance
20 mm (15 mm + 5 mm) Spacer ![]() Click to Enlarge Click Here for Raw (2048 x 2048) Image RSP1X15 rotation mount imaged using a 4070M-GE Scientific Camera and MVL25M43 Lens at different object distances. A 20 mm spacer was created by using CML05 and CML15 spacers together.
Thorlabs' Threading SpecificationsThorlabs' 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 C-Mount extension tubes introduce a fixed spacing between C-Mount components, such as Thorlabs' CCD/CMOS cameras and camera lenses. They have a stackable design and C-Mount (1.00"-32) threads for direct compatibility with any C-Mount components. The CML05 CS-Mount to C-Mount Extension Adapter is sized to increase the flange-to-sensor distance of a CS-Mount camera by 5 mm (0.39") to match the C-Mount standard distance. These extension tubes have a 0.97" (24.6 mm) inner diameter that is too small to accept Ø1" (Ø25.4 mm) or Ø25 mm (Ø0.98") optics. Optics with diameters between 0.87" (22.0 mm) and 0.97" (24.6 mm) can be secured inside these tubes with C-Mount retaining rings. These extension tubes do not include C-Mount retaining rings, which can be purchased below.
![]() ![]() Click to Enlarge CMSP100 Spacer Ring Between CML100 and CML15 Extension Tubes
These C-Mount Spacer Rings fit between two C-Mount (1.00"-32) components, such as Thorlabs' C-Mount extension tubes, camera lenses, and CCD/CMOS cameras. Much like the extension tubes sold above, the rings add length to an optical system. As shown to the right, these spacer rings fit over external C-Mount threads and allow for much finer adjustments of the spacing between components. The rings must be introduced between two other C-Mount components. They are constructed from brass and laser engraved with a part number. ![]()
Our C-Mount-threaded (1.00"-32) retaining ring is ideal for securing components into our C-Mount extension tubes, CMR lens mount, and C- or CS-Mount compatible CCD and CMOS cameras. As shown in the photo to the left, these retaining rings are engraved with both the part number and "C-Mount" to distinguish it from our SM-threaded retaining rings. Each retaining ring is machined with two slots for compatibility with our SPW801 adjustable spanner wrench, which is sold below. Note that Thorlabs' C-Mount extension tubes cannot accept Ø1" (25.4 mm) or Ø25 mm (0.98") optics. ![]()
These kits contain a variety of thicknesses/lengths to allow for fine/coarse adjustment of the image distance without having to search for a single piece to provide the right distance. Both kits contain a CS- to C-Mount extension adapter to allow compatibility with both types of lenses and cameras. In addition, the CML-KIT comes with two CMRR C-Mount retaining rings.
![]() Click to Enlarge Contents of CML-KIT ![]()
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 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. Hence, compared to our cylindrical spanner wrenches sold above, the SPW801 is ideal for securing lenses with a high radius of curvature because the guide flanges on the cylindrical spanner wrenches may come into contact with the lens. 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). | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|