FWO-B 30mm Filter Wheel

Product Description

• Compatible with 30mm cage systems.
• Rotate the wheel to quickly switch filters.
• Filter wheel notches feature SM1 (1.035”-40) threads, included with CSK3 retaining rings.
• SM1 (1.035”-40) internal thread ports, compatible with lens sleeves.

The FWO-B filter wheel is compatible with 30mm coaxial systems, featuring six filter holders with SM1 threads. The fixed input and output ports on the main body also have SM1 threads for compatibility with our Ø1-inch lens sleeves, and align the filter center with the cage system.

Model	FWO-B
Dimensions	88.6*28.0*102.3mm
Wheel Notches	SM1 (1.035”-40) internal threads, compatible with Ø1-inch lenses up to 4.5mm thick
Thread Type	Port: SM1 (1.035”-40) internal threads; M4/M6 screw holes
Weight	163.2g
Material	7075 aluminum alloy

Technical Description

Optical Knowledge Point: Common Optical Thread Size Standards

This is a thread specific to Thorlabs Inc. (USA) and not a commonly used optical thread. “SM” is the code for sewing machine threads in thread notation, but this American company uses it for internal and external thread connections of optical lenses and sleeves. The thread type is UNS (Unified National Special Thread) with a tolerance class of 2A/2B. A unique feature of this thread is that regardless of the diameter, the pitch is 40 threads per inch (TPI). Specific dimensions are as follows:

Series	Type	Thread (in)	Nominal Diameter (mm)	Minor Diameter (mm)	Pitch Diameter (mm)	Major Diameter (mm)
SM05	Internal	0.535-40	13.59	12.98±0.07	13.24±0.05	＞13.59
SM05	External	0.535-40	13.59	＜12.78	13.10±0.05	13.50±0.05
SM1	Internal	1.535-40	26.29	25.68±0.07	25.95±0.05	＞26.29
SM1	External	1.535-40	26.29	＜25.48	25.79±0.05	26.19±0.06
SM2	Internal	2.535-40	51.69	51.08±0.075	51.35±0.075	＞51.69
SM2	External	2.535-40	51.69	＜50.87	51.18±0.05	51.59±0.05

Product Description

The FWO-B filter wheel is compatible with 30mm coaxial systems, featuring six filter holders with SM1 threads. The filter wheel is positioned via internal steel ball mechanical detents and aligns the filter center with the cage system. It can mount Ø1-inch optical components up to 4.5mm thick, with lenses fixed using the included retaining rings.

The fixed input and output ports on the main body also have SM1 threads for compatibility with our Ø1-inch lens sleeves. The sides of the cage rod through holes are equipped with set screws, which can fix the position of the cage rod using a 1.6mm hex wrench. (Note: Cage rods cannot pass through the through holes as they will be blocked by the filter wheel.)

The bottom is equipped with M4 and M6 screw holes for easy compatibility and installation of optomechanical components.

Assembly

Application Example

Engineering Drawing Download

FWO-B-Engineering Drawing2