High-Speed Focusers

  • Z-Axis Translation at High Frequency
  • Dynamic Focusing for Scanning Systems
  • Optional Bonded Lens for UV or Nd:YAG Lasers


High-Speed Translator

US Patent 11,090,761

Included Servo Driver

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Volume Pricing Discount

Large-Volume Orders

For orders where a large quantity of an item is purchased and the delivery of that item is scheduled with our production (i.e., not taken directly from inventory), Thorlabs passes on to the customer the cost savings associated with planned production of high volumes of that item. Since the volume and planned production are key to realizing the cost savings, we ask that you contact us to obtain volume pricing.

Additional requests can include custom optic sizes and coatings, specialized tuning, and variable cable options.

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Key Specificationsa
Lens Coating N/A 1000 - 1550 nm 240 - 400 nm
Lens Size N/A Ø12.7 mm
Travel Range 13 mm
Servo Bandwidth >500 Hz
System Resolution 200 nm
System Repeatability 800 nm
  • See the Specs tab for complete specifications.


  • Dynamic Z-Axis Scanning
  • Provides Focal Correction for 2-Axis Scanning Systems
  • Capable of Continuous Operation at 50g Sine Wave
  • Non-Contact Air Bearings with Voice-Coil Driver
  • Servo Driver Included
  • >500 Hz Servo Bandwidth

The BLINK High-Speed Focuser (US Patent 11,090,761) is designed to dynamically map a focal correction onto the laser beam as a function of its XY position. By translating a focusing lens at high frequencies along the optical axis, the focuser adjusts the effective focal point of a galvo scanning system to account for large angles or arbitrary surfaces. When used as the focusing element of a post-objective scanning system, BLINK allows high-speed processing of large planar samples and 3D contoured samples. See the 2-Axis vs. 3-Axis tab for more information.

BLINK combines an air bearing guideway with direct voice-coil drive, resulting in a very compact, high-performance focuser. It is capable of continuous operation with a 50g peak sine wave, and its ultra low moving mass minimizes reaction forces. With only one moving part, BLINK offers exceptional reliability and service life compared to traditional taut band actuators.

The focuser includes an aluminum mounting bracket with two through holes for 1/4"-20 (M6) cap screws. Four M3 tapped mounting holes are located on the top of the unit (two on the mounting bracket and two on the cylindrical lens housing). Four M3 tapped holes around the aperture are spaced 0.92" apart for custom mounting applications.

Focusers are available with or without a bonded lens. The lens can be coated for UV (355 nm) or Nd:YAG (1064 nm) lasers.

The compatible power supply (item # GPWR15) and cable set (item # CBLS2F) are sold separately.

Included Lens
Coating Wavelength Range N/A 1000 - 1550 nm 245 - 400 nm
Effective Focal Length N/A -75 mm
Size See Footnote a Ø12.7 mm
Clear Aperture See Footnote b Ø12.4 mm
Mass N/A 2 g
Travel Range 13 mm
Servo Bandwidth >500 Hzc
Force Constant (K) 6.1 N/Amp
Coil Resistance 4.5 Ω
Position Detector Resolution 0.2 nm
System Resolution 200 nm
System Repeatability 800 nm
Unit Mass 540 g
Air Supply Cleanliness Class 3 or Better
Air Supply Pressure 60 - 90 PSI
Air Supply Flow Rate <2.5 LPM @ 80 PSI
  • BLINK units without a bonded optic have a Ø12.7 mm lens cell to accommodate an optic with a thickness of 1.00 - 3.35 mm.
  • A non-bonded lens will have a clear aperture of Ø11 mm.
  • With a 2 V peak-to-peak sine wave, the unit can operate up to approximately 95 Hz before falling out of sync with the commands being issued.
Servo Amplifier Specsa
Command Input Range ±5 V
Position Input Scale Factor 0.22 V/° Optical
Command Input Impedance 400 kΩ (Differential)
200 kΩ (Single Ended)
Position Offset Range ±0.25 V
External Enable TTL (Low: Disable Drive)
Diagnostic Outputs
Servo Ready TTL
Position 0.22 V/° Optical
Position Error 0.22 V/° Optical
Velocity Analog (Reference Only)
AGC Voltage Analog (DC)
Coil Current 1 V/A
Analog Output Impedance Unbuffered
Power Supply (Not Included)
Input Voltage ±15 VDC
<100 mV Ripple
<0.5% DC to 30 MHz Noise
Maximum Drive Current Limit 3 A (RMS); 10 A (Peak)
Quiescent Current 220 mA (Servo Enabled, Galvo at Rest)
Gain Drift Up to 20 ppm/°C
Offset Drift Up to 26 µrad/°C
General Specs
Operating Temperature 0 to 45 °C (With Appropriate Cooling)
Storage Temperature -10 to 60 °C
Dimensions 2.38" x 2.22" x 1.06"
(60.5 mm x 56.4 mm x 27.0 mm)
Mass (Weight) 49 g (1.7 oz)
  • Specifications are obtained after a 2 minute warm-up period.
  • The enable pin is soldered in the on position at the factory. To enable remote control, remove the solder or contact us prior to purchase to obtain an unsoldered unit.

GPWR15 Power Supply Unit Specs

Parameter Value
Input 100 - 120 VAC or 220 - 240 VAC
Output ±15 V at 5 A (150 W Max Power)
Operating Temperature 0 to 50 °C
Dimensions 14.0" x 4.9" x 3.5"
(356 mm x 124 mm x 90 mm)

Dynamic Performance for a 1.0 mm Stroke Reference Move

Frequency Peak Acceleration Peak Current Average Power
Bonded Lens
100 Hz 197 m/s2 (20g) 1.0 A 2.3 W
125 Hz 308 m/s2 (31g) 1.4 A 4.4 W
141 Hz 392 m/s2 (40g) 1.8 A 7.3 W
157 Hz 487 m/s2 (50g) 2.2 A 11.1 W
Removable Lens
100 Hz 197 m/s2 (20g) 1.1 A 2.7 W
125 Hz 308 m/s2 (31g) 1.5 A 5.2 W
141 Hz 392 m/s2 (40g) 2.0 A 8.6 W
157 Hz 487 m/s2 (50g) 2.4 A 13.2 W
Dynamic Focusing Galvo
Click to Enlarge

Diagram Illustrating Dynamic Focusing to Achieve a Flat Field in Our XG300 Series and DCB320-Y1 Three-Axis Galvo Scan Heads

In a typical two axis laser scanning system, a collimated beam is reflected by the X and Y axis scanning mirrors before entering the focusing (objective) lens. The lens focuses the beam on the work surface. Rotation of the X and Y mirrors causes movement of the focused spot within a flat field. The size of the spot and the size of the field are determined by the lens (and other factors). This configuration is known as a pre-objective scanning system because the laser strikes the scanning mirrors before the focusing (objective) lens. An f-theta lens is a common choice for the lens in this configuration.

The architecture works well as long as the beam diameter and field size are relatively small. For example, applications using beam diameters less than 20 mm and field sizes less than 300 mm are well suited to Z-axis pre-objective scanning.

As the field size requirements grow, larger scan mirrors and laser beam diameters are needed to maintain a numerical aperture (NA) consistent with a small focused spot. F-theta scan lenses for these large laser beams would be big, costly, and impractical. For this reason, a 3-axis scanning solution should be considered.

In a 3-axis scanning system, as shown in the figure to the right, the XY mirrors are placed after the final focusing lens, and hence they are referred to as a post-objective scanning system. Since the laser beam does not move on the objective lens, the lens does not need to be very large; however, this arrangement does not create a flat field. To achieve a flat field, a third axis (Z-axis) of motion is introduced in the form of a linear lens translator.

The typical laser system uses a telescope to expand the laser beam to a diameter consistent with the required NA. The distance between the telescope input lens and objective lens determines the focal distance of the system. By mounting the input lens on a linear lens translator (the third axis), we gain dynamic control over the focal distance. See the diagram to the right for details.

By coordinating the motion of the linear lens translator with the rotation of the X and Y scanning mirrors, we achieve a focused laser spot throughout a flat field. Alternatively, the same configuration can be used to scan a three-dimensional surface. In this scenario, the Z-axis position is an arbitrary function of the X and Y galvo mirror positions, enabling the system to scan complex geometries.

Posted Comments:
Mostafa Aakhte  (posted 2022-08-08 09:07:21.937)
Is it possible to gather information regarding the position of the voice coil during motion? or is there an encoder around the voice coil?
Weijan Zong  (posted 2021-09-04 13:29:37.737)
Can this z-focusing device (BLINK) stay in a certain focus as demond, or it has be be scanning?
YLohia  (posted 2021-09-08 01:35:24.0)
The unit can be “parked” at a specific location. You would want to do this for the drill mode, where you want to hold focus at a specific point for your laser to do some processing and then move it to a different point afterwards. You can put any arbitrary signal into this that would suit the customer’s requirements, similar to a galvo. The QD-2000 is a servo controller that tries to match the galvos position signal with the command input signal, so will try and have that match whether the signal is moving in a sine wave, stopped and parked, a triangle wave, or anywhere in between. This could be driven off any analog function generator or DAC that you're familiar with that is able to generate what you're looking for.

High-Speed Focusers

Based on your currency / country selection, your order will ship from Newton, New Jersey  
+1 Qty Docs Part Number - Universal Price Available
BLINK Support Documentation
BLINKHigh-Speed Focuser
Lead Time
BLINK-Y1 Support Documentation
BLINK-Y1High-Speed Focuser, Bonded Lens for Nd:YAG Lasers
BLINK-Y3 Support Documentation
BLINK-Y3High-Speed Focuser, Bonded Lens for 355 nm Lasers
CBLS2F Support Documentation
CBLS2FCommand and Power Cables for BLINK & QS7/10 Series Galvo Scanners (Single Axis)
GPWR15 Support Documentation
GPWR15±15 V Power Supply for BLINK & QS, SS, SP, & XG Series Galvo Scanners