Special Optics 56B-30-1X-4X User Manual

Motorized zoom beam expander

Motorized Zoom Beam Expander (56B-30-1X-4X)

Users' Manual

Special Optics' Motorized Zoom Beam Expanders are designed to receive a collimated laser

beam and to increase the beam diameter while maintaining a collimated output beam.

Model 56B-30-1X-4X-λ is a beam expander that offers 13 different expansion ratios: 1.00X,

1.25X, 1.50X, ...4.00X. The user specifies a wavelength when ordering the beam expander. This

assures that the antireflection coatings on the lenses will be optimized for the user's primary

Wavelength. Model 56B-30-1X-4X is designed to operate at 13 standard wavelengths: 256 nm,

355 nm, 458 nm, 488 nm, 514.5 nm, 532 nm, 632.8 nm, 780 nm, 800 nm, 1064 nm, and 1550 nm.

Custom versions for other wavelengths are available. Since the fused-silica optics are identical for

all wavelengths, only the wavelength settings in software need to be changed. Special Optics has

developed a Dynamic Link Library (dll) to operate our Motorized Zoom Beam Expander. This dll

can be called from any program, but we provide an executable file (exe), which operates in a Win-

dows environment, to drive the dll.

1. Optical Layout

The Motorized Zoom Beam Expander comprises three lens groups, two of which move during

Operation. Figure 1 shows the three lens groups and indicates that Lens Group 1 and Lens Group 2

move when the expansion ratio is changed. There are two motors in the system. Motor 1 moves

Lens Group 1, thereby controlling the air space (t

) between Lens Group 1 and the Motor Mount-

ing Plate. Motor 2 moves Lens Group 2 and controls the air space (t

) between Lens Group 2 and

Lens Group 3, which is fixed. The unit is supplied with a text files that contain nominal values of

and t

for eleven wavelengths and thirteen expansion ratios. These values were established at

Special Optics using a shear-plate interferometer to optimize collimation settings at all of the

Expansion Ratios for several wavelengths. Values for these two air spaces will vary from labora-

tory to laboratory since they are a function of the collimation properties of the testing beam. Users

should verify that the settings are optimized for their particular set of beam parameters.

Figure 1. Optical components in zoom beam expander.

Table of Contents

Do you have a question about the 56B-30-1X-4X and is the answer not in the manual?

Page 1 Model 56B-30-1X-4X-λ is a beam expander that offers 13 different expansion ratios: 1.00X, 1.25X, 1.50X, …4.00X. The user specifies a wavelength when ordering the beam expander. This assures that the antireflection coatings on the lenses will be optimized for the user’s primary...
Page 2 2. Files The system is supplied with an installation disk for a Windows operating system. The user should double click on the setup icon to start the installation. This will install all necessary files in their proper locations on the user’s computer. Included in this installation is National Instrument’s Runtime Engine 8.0, which is required to operate the dll file since it includes calls to functions in National Instruments’...
Page 3 4. Tweak step. During adjustment of the calibration, the user activates the Tweak func- tion. Motor steps are 0.2, 0.4, or 1.0 times the tweak step in millimeters. The default value is 0.2 mm. It is unlikely that the user will need to change this, but the option is available.
Page 4 Tweak Because beam divergences of input test beams vary, it is possible that the factory settings of lens positions may not be perfect for the user’s system. We have provided a Tweak control to make adjustments to the lens positions. There are three speeds (slow, med, and max) in both the positive and negative directions.