30 mm Cage System U-Bench

  • Ideal For Introducing Optomechanics Within A Rigid Cage Assembly
  • Generous Array of 1/4"-20 (M6 x 1.0) and 8-32 (M4 x 0.7) Tapped Holes
  • SM1 (1.035"-40) Threaded Holes at Interface Ends


SM1 (1.035"-40)

Standard 30 mm Cage
Mounting Pattern

Application Idea

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  • Compatible With Standard 30 mm Cage System Spacing
  • SM1 (1.035"-40) Tapped Holes at Both Interface Ends
  • Solid One-Piece Construction Maintains System Alignment
  • Provides the Extra Space Required for a Wide Range of Optical Components to be Used in Line With the Cage Structure

The CBB1(/M) Cage System U-Bench provides a tapped mounting surface within a standard 30 mm cage assembly or a Ø1" lens tube setup. A generous supply of 1/4"-20 (M6 x 1.0) and 8-32 (M4 x 0.7) tapped holes provide the flexibility necessary to construct small optical assemblies within the U-Bench that might not otherwise fit within the standard cage rods. The U-bench is made from a single piece of aluminum and finished with precision machining to provide stability and maintain the alignment of the overall system. Each end is tapped with our standard SM1 (1.035"-40) thread making it compatible with a wide range of optical mounting components such as our Ø1" lens tubes. Each cage rod through hole is accompanied by a side-located M4 x 0.7 locking setscrew with a 5/64" (2.0 mm) hex.

Cage System Overview

The Cage Assembly System provides a convenient way to construct large optomechanical systems with an established line of precision-machined building blocks designed for high flexibility and accurate alignment.

16 mm, 30 mm, and 60 mm Cage System Standards

Thorlabs offers three standards defined by the center-to-center spacing of the cage assembly rods (see image below). The 16 mm cage, 30 mm cage, and 60 mm cage standards are designed to accomodate Ø1/2", Ø1", and Ø2" optics, respectively. Specialized cage plates that allow smaller optics to be directly inserted into our larger cage systems are also available.

Standard Threads

The flexibility of our Cage Assembly System stems from well-defined mounting and thread standards designed to directly interface with a wide range of specialized products. The three most prevalent thread standards are our SM05 Series (0.535"-40 thread), SM1 Series (1.035"-40 thread), and SM2 Series (2.035"-40 thread), all of which were defined to house the industry's most common optic sizes. Essential building blocks, such as our popular lens tubes, directly interface to these standards.

An example of the standard cage plate measurements determining cage system compatibility.
Standard Cage System Measurements
Cage System 16 mm 30 mm 60 mm
Thread Series SM05 SM1 SM2
Rod to Rod Spacing 16 mm (0.63") 30 mm (1.18") 60 mm (2.36")
Total Length 25 mm (0.98") 41 mm (1.60") 71.1 mm (2.8")
Cage Components
Cage Rods 16 mm These rods are used to connect cage plates, optic mounts, and other components in the cage system. The SR Series Cage Rods are compatible with our 16 mm cage systems, while the 30 mm and 60 mm cage systems use ER Series Cage Rods.
30 mm
60 mm
Cage Plates 16 mm These serve as the basic building blocks for a cage system. They may have SM-threaded central bores, smooth bores sized for industry standard optics or to accommodate the outer profile of our SM Series Lens Tubes, or specialized bores for other components such as our FiberPorts.
30 mm
60 mm
Optic Mounts 16 mm Thorlabs offers fixed, kinematic, rotation, and translation mounts specifically designed for our Cage Systems.
30 mm
60 mm
Cage Cubes 16 mm These cubes are useful for housing larger optical components, such as prisms or mirrors, or optics that need to sit at an angle to the beam path, such as beamsplitters. Our cage cubes are available empty or with pre-mounted optics.
30 mm
60 mm
Replacement Setscrews Replacement setscrews are offered for our 16 mm (SS4B013, SS4B025, and SS4B038) and 30 mm (SS4MS5 and SS4MS4) cage systems products.
Post and Breadboard Mounts and Adapters Mounting options for cage systems can be found on our Cage System Construction pages. Cage Systems can be mounted either parallel or perpendicular to the table surface.
Size Adapters Cage System Size Adapters can be used to integrate components from different cage system and threading standards.
Specialized Components Thorlabs also produces specialized cage components, such as Filter Wheels, a HeNe Laser Mount, and a FiberPort Cage Plate Adapter, allowing a wide range of our products to be integrated into cage-mounted optical systems. Explore our Cage Systems Visual Navigation Guide to see the full range of Thorlabs' cage components.

Posted Comments:
Michael Levin  (posted 2020-08-26 03:10:01.13)
What is the difference between the new CCB1 and the obsolete CB1?
YLohia  (posted 2020-08-26 10:51:05.0)
Hello Michael, thank you for contacting Thorlabs. The 4-40 cup-tip setscrews were changed to M4 x 0.7 cone-tip screws. This increases drive size from 0.050” to 5/64” (2 mm). It makes it less likely for users to accidentally strip screw threads in cage plate and also improves resistance to shifting the cage plates when locking/unlocking.
Farhad Akhoundi  (posted 2020-03-10 17:11:54.353)
It would be great if you make the same component with shorter length. For example 20 to 30 mm length
YLohia  (posted 2020-03-11 03:10:31.0)
Thank you for contacting Thorlabs. I have posted your request on our internal engineering forum for further consideration as a future product.
schoenbp  (posted 2016-10-19 07:32:21.397)
Are those CB1/M U-Benches available with custom lengths? This would allow for mounting them to xyz-translation stages sturdily and implement a variety of collimation/focusing optical elements in between.
jlow  (posted 2016-10-19 02:14:24.0)
Response from Jeremy at Thorlabs: We can make this with custom length. I will contact you directly about this.

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+1 Qty Docs Part Number - Imperial Price Available
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+1 Qty Docs Part Number - Metric Price Available
CBB1/M Support Documentation
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