Thorlabs Inc.
Visit the Motorized Fast-Change Filter Wheel page for pricing and availability information

Motorized Fast-Change Filter Wheel

  • 55 ms Filter Change Time with Included Controller
  • Light-tight Design
  • Cage and Lens Tube Compatible


Motorized Filter Wheel
(BSC201 Controller Included)


High-Speed Switching Controller

Application Idea

Compatible with Our Ø1/2" Posts,
30 mm Cage System, and
SM1 Lens Tube Components

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Motorized Filter Wheel Selection Guide
Item # # of Slots Filter Size Preloaded ND Filters Features
FW212C 12 Ø1/2" No BNC, RS-232 and USB Interfaces
Integrated Controller
FW212CNEB 12 Ø1/2" Yes
FW102C 6 Ø1" No
FW102CNEB 6 Ø1" Yes
FW103H 6 Ø1" No 55 ms Switching Time


  • Change Time of 55 - 60 ms When Used with Included BSC201 Controller
  • Holds up to Six Ø1" (Ø25 mm) Filters
  • Accepts Filters up to 0.25" (6.35 mm) Thick
  • Light-Tight Design
  • Filters Easily Added or Removed
  • Compatible with All apt™ Stepper Motor Controllers

This motorized fast-change filter wheel has been designed for applications that require sequential observations with different filters inserted in the optical path, such as multi-wavelength fluorescence imaging. The optical port is internally SM1 (1.035"-40) threaded on both sides for compatibility with our Ø1" lens tubes, and each side contains four 4-40 taps for compatibility with our 30 mm cage systems. The perimeter of the housing contains four 8-32 (M4) tapped holes at 90° spacings to allow the wheel to be mounted on Ø1/2" posts. Up to six Ø1" (Ø25.4 mm) filters mounted in the standard housing (e.g., Thorlabs' FEL series) can be fitted onto the wheel. A removable cover allows filters to be installed without needing to unmount the filter wheel from the optomechanical setup within which it sits.

The FW103H(/M) includes the filter wheel and our BSC201 Single-Channel apt™ Controller, which provides a switching time between 55 - 60 ms for adjacent filters. The BSC201 comes with a power supply for 110 to 240 V and with a US, UK, or European power cord determined by your ordering location. The filter wheel can also be used with the TST101 T-Cube controller, but the switching time will increase to 250 ms. If you are interested in this option, please contact Technical Support to inquire about purchasing a filter wheel without the BSC201 controller.

The filter wheel uses a Hall effect sensor to determine the filter wheel's position, which is ideal for light-sensitive applications.

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The Motorized Fast-Change Filter Wheel can hold up to six Ø1" filters, which can be easily inserted into the wheel in three steps.

Step 1

Filter Wheel Housing Removal
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Remove the housing cover to gain access to the six filter slots (individual filters can be changed by using the filter access cover located on the housing cover, shown to the bottom left)

Step 2

Filter Installation
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Insert the filter into the desired port of the filter wheel

Step 3

Filter Installation
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Secure the filter's position using one of the provided retention rings and three screws (M2 x 8 for 6.35 mm filter or M2 x 6 for thinner filters) as shown above

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Motor Connector

D-type Male

D-type Motor Connector

1Limit Switch Ground6Phase A -ve11NC
2O/P Positive Limit Switch7Phase A +ve12NC
3O/P Negative Limit Switch8NC13NC
4Phase B -ve9NC14NC
5Phase B +ve10+ 5 V DC15Ground/Earth

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Part Number
Motorized Filter Wheel with High-Current BSC201 Controller, M4 Taps
Motorized Filter Wheel with High-Current BSC201 Controller, 8-32 Taps