Ronar-Smith Beam Expanders: Fixed, Zoom and CO2 Laser Models

Ronar-Smith® beam expanders increase the diameter of a collimated laser beam to reduce divergence, so the beam travels further before it spreads. Whether you’re matching a fiber laser’s output to the input aperture of a scan lens, preparing a beam for a galvo head, or setting the spot size on a CO2 cutting system, the range covers fixed, manual zoom and motorized zoom designs from ultraviolet through infrared wavelengths. All models are telescopic. They require a collimated input and deliver a collimated, expanded output. Every beam expander is tested before release.

Fixed, zoom and motorized options

Fixed Beam Expanders (BEX) use a Galilean design without an internal focus. Magnification runs from 1x – 50x, and beam divergence is adjustable. Pointing stability is < 1 mrad. Use them where the expansion ratio is set by the optical design, for example when adapting a laser’s output diameter to the input of an objective lens, or on a dedicated engraving or marking line. Anti-reflection coatings and high transmissivity keep losses low. A fixed unit cannot change output beam size, so it is the wrong choice if your process needs that adjustment.

Manual Zoom Beam Expanders (BXZ) let you set magnification continuously by hand. Internal translation stages and focusing mechanisms adjust magnification and compensate for laser divergence without changing the overall housing length. That makes them easy to drop into an existing beam path. They are designed for high-power applications where you need to change magnification between processes.

Motorized Zoom Beam Expanders (BXZ-MOT) use the same continuous-zoom optical concept under automatic control. They communicate over RS232 and USB at 19200 bps and run from a 9V supply. Adjustment takes about 5 sec per magnification step. Choose these for production equipment where spot size changes between jobs and is set by the machine controller rather than an operator.

CO2 laser beam expanders

For 10.6 µm-class CO2 systems, the range includes three dedicated families:

• UniBET: for CO2 lasers above >100W without water cooling. These are Galilean designs with fixed magnifications of 1.5x – 10x and adjustable divergence. They share a consistent outer dimension and an M30x1 connecting thread, which simplifies swapping magnifications on the same mount.
• MiniBET: a compact series for CO2 lasers above >100W. All models share a 20mm external diameter and an M16x0.75 thread, so they suit space-constrained laser heads.
• BET-WC: water-cooled beam expanders for CO2 systems above >200W, where thermal load on the optics becomes a concern.

Applications and customization

Ronar-Smith beam expanders are used in:

• Laser machining, cutting and drilling
• Laser marking and engraving
• Laser scanning
• Laser cleaning
• Solar panel scribing and grooving

They are also used in research setups such as laser spectroscopy and microscopy, where a larger, better-collimated beam is needed.

If a catalogue part doesn’t match your system, Wavelength can customize the following:

• Wavelength-specific filtering
• Anti-reflection coating
• Magnification factor
• Input and output clear aperture
• Maximum beam intensity

Send your laser parameters and mechanical constraints through the RFQ form.

Why buy through Wavelength Optics USA

Wavelength Optics is the US arm of Wavelength Opto-Electronic, the Singapore manufacturer of the Ronar-Smith® line. Working with the US team gives you:

• Local support in your time zone.
• Fast quoting on catalogue and custom parts.
• Selection help from engineers who can work through the trade-offs with you:
  • Fixed versus zoom
  • Input beam diameter against clear aperture
  • Mounting thread compatibility
  • Whether a CO2 application calls for UniBET, MiniBET or water cooling

Use the specification table on this page to filter the full catalogue by the following:

• Wavelength
• Magnification
• Type
• Clear aperture
• Thread
• Dimensions

Contact Wavelength Optics USA when you’re ready to quote or need help narrowing the options.