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The top of each coil assembly includes SM threads and threaded holes for mounting to other components. See the table below for details.

Features

• Linear Voice Coil Motors
• Direct Force Drive for High Purity of Motion
• Up to 62.5 mm Maximum Travel
• Current-Driven Operation
• High-Speed, Precise Translation
• Highly Responsive Acceleration and Deceleration
• SM-Threaded Coil Assembly

Thorlabs' voice coil actuators are designed for use in applications requiring positioning with high speed or acceleration. These linear actuators use a bobbin and magnet assembly to provide linear force without contact between the moving and fixed world. The voice coil converts electrical signals directly into linear magnetic force, providing much higher purity of motion compared to DC motors requiring separate drivetrains such as belts or gears. When combined with a position sensor, our voice coils provide quick, accurate movement with excellent repeatability. The polarity of the voltage determines the translation direction of the motor. When using the red wire for positive voltage, the magnet assembly will extend when current is applied. The force can be approximated by multiplying the current by the force constant, although the position of the actuator will also affect the force provided by the actuator (see the graphs in the table below for details).

Both ends of the voice coil actuator should be firmly mounted so that the magnet assembly is suspended around the voice coil without contact. The VC063/M and VC125/M magnet assemblies have a center blind-tapped M3 mounting hole, while their coil assemblies have a center M3 mounting hole. The VC250/M, VC500/M, and VC600/M magnet assemblies have a center blind-tapped M6 mounting hole, while their coil assemblies have two M4 mounting holes on opposite sides of a center Ø6.35 mm through hole. The mounting holes could be used with our right-angle brackets to fix either end of the voice coil to an optical table or moving world of a stage. All voice coil assemblies have external SM threading for easier mounting to our fixed optic mounts or lens tubes.

If the voice coil actuator is translated beyond its maximum recommended travel range, the magnet assembly may be displaced too far from the coil assembly to maintain proper magnetic interaction. In this case, the actuator may no longer respond as expected and the voice coil must be manually contracted.