Variable Beam Expander Theory

Various magnifications are available but it is important to ensure that the input and output beams clear the apertures.

Variable beam expander theory.

Where f 1 is the focal length of the positive lens and f 2 is the focal length of the negative lens. The mechanics used to focus a beam expander or change the magnification of a variable beam expander are typically classified into two different types. Once the desired beam size and divergence is reached the position can be locked with two sets of screws. The design is compact and suitable for an industrial environment.

All optical elements of beam expanders are made of fused silica with high lidt coatings and provide stable and reliable performance even using them with high power lasers. The magnification of a galilean beam expander is determined by the following equations. Those contain at least three lenses and some fine mechanics to adjust the position of at least one of them. Beam expanders improve a beam s collimation.

Beam expanders thorlabs galilean type beam expanders which are available in both fixed and variable magnification options are offered for use in the uv visible near infrared and mid infrared spectral ranges. 2 optical track length f 1 f 2 optical track length f 1 f 2. Techspec research grade variable beam expanders feature λ 4 transmitted wavefront galilean designs and high laser damage threshold ar coatings to ensure maximum transmittance while minimizing ghost reflections. There are variable beam expanders zoom expanders i e devices where the magnification can be adjusted in a certain range e g.

Rotating focusing mechanisms such as threaded focusing tubes rotate the optical elements during translation. 1 magnification power f 1 f 2 magnification power f 1 f 2. Beam expanders have numerous uses. A beam expander with adjustable magnification.

Beam expanders also known as collimators or up collimators typically are used in systems with a long beam path to keep the beam collimated or to vary the focus spot size for a given focusing lens. These variable magnification zoom beam expanders are designed for required wavelength and each type of our beam expanders has a divergence adjustability. Techspec research grade variable beam expanders rvbx are ideal for high power laser applications where magnification changes may be required such as prototyping or r d. The zoom is adjusted by turning the magnification.

Thorlabs 0 5x to 2x galilean variable beam expanders reducers allow the user to easily adjust the beam diameter without altering the alignment of the optical setup. Our variable beam expanders allow separate magnification and divergence adjustment. From 2 to 5 or from 5 to 10. The fixed magnification sliding lens beam expanders are offered with optics that have either narrowband or wideband ar coatings.