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.

Features

• 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 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.

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.