
Beam Shaping
Aspheric laser beam shaper
With the a|TopShape, a|AiryShape, and a|SqAiryShape from the laser beam shaping range, asphericon offers efficient top hat beam shapers for maximum results in all laser applications. Based on aspherical optics, these modular components allow the straightforward transformation of Gaussian laser beams into various round and square top hat profiles. Thanks to highly precise manufacturing technology, these laser beam shapers are distinguished by unparalleled beam quality and can be used in diverse applications.
The input and output beams of the beam shapers are freely scalable. Their wide spectral range (300–2,500 nm) is suitable for applications in metrology, microscopy and materials processing. The a|TopShape (for beam profiles up to 300 mm, available in a LongDistance (LD) version for up to 1.5 m as well as an LDX model for 1.5 m and movable to larger working distances), the a|AiryShape and the a|SqAiryShape can all be used not only with a collimated laser beam but also with a fiber-coupled source. Despite their compact size, these beam shapers deliver outstanding optical quality. Thanks to their modular design and asphericon’s mounting concept with easy-to-screw threads and a large selection of adapters, the laser beam shapers are straightforward to connect without further adjustment. In addition, they’re simple to use and can be easily integrated into existing setups. Moreover, they can be combined with additional beam expander components. The high-precision installation of these beam shapers in their mount enables them to be perfectly aligned within the beam path.

a|TopShape
The a|TopShape is an innovative beam shaper that transforms collimated Gaussian beams into slightly enlarged (M ≈ 1.5) collimated top hat beams with uniform intensity distribution. It’s distinguished by its compact design and outstanding optical quality (beam uniformity < 0.1). The laser beam shaper covers a wide spectral range (320–2,500 nm), accepts different input beam diameters up to ±10%, and generates a stable beam profile for at least 300 mm. Using the LongDistance version (a|TopShape LD), even homogeneous beam profiles can be achieved at a working distance of up to 1.5 m. With the new a|TopShape LDX, the beam profile can be shifted to large working distances of up to 3 m by adjusting the input beam diameter. Since the effective working distance decreases as the beam size is reduced, a|TopShape LD and LDX are particularly suitable for applications requiring smaller beam diameters. For applications where the beam profile’s homogeneity is less crucial, longer working distances are also possible (see Flexibility).
- Outstanding optical quality (beam uniformity up to 0.05) without drop in performance
- Wide spectral range (320–2,500 nm) and suitable for multi-wavelength applications
- Propagation depth (with beam uniformity < 0.1):
- a|TopShape: At least 300 mm
- a|TopShape: LD up to 1.5 m
- a|TopShape LDX: At least 1.5 m – can be shifted to longer working distances of at least 3 m
- Input beam diameter:
- @ 1/e² = 10 mm (± 10%) for a|TopShape and a|TopShape LD
- @ 1/e² = 10.0–10.4 mm for a|TopShape LDX
- Output beam diameter@ FWHM = between 15.2 mm and 15.7 mm
- Laser induced damage threshold: 12 J/cm², 100 Hz, 6 ns, 532 nm, 532 nm
For applications with higher laser power, we invite you to explore our V-coating options. Contact us for a personalized solution tailored to your needs.
The following figures show the measured wavefront after passing 14 surfaces, including seven aspheres (left) and the beam profile after passing 12 surfaces, including six aspheres, at a working distance of 100 mm (right). The resulting RMS wavefront error of 0.05 λ, which corresponds with a Strehl value of 0.9, proves the very high optical quality. The resulting Beam Uniformity of 0.1 and the ISO Edge Steepness of 0.4 emphasizes this.


The outstanding feature of a|TopShape LD is its long and stable propagation distance. The figure on the right displays the intensity distribution at a working distance of 3000 mm. It is characterized by an ISO Beam Uniformity of 0.1.

The key feature of the TopShape LD and LDX is their long, stable propagation distance. The following figure shows the intensity distribution at working distances of 100 mm, 800 mm, 1500 mm, and 3200 mm. They’re both characterized by beam uniformity of 0.05 up to 1,500 mm. By varying the input beam diameter, beam uniformity of 0.06 up to as much as 3,200 mm can be guaranteed for the TopShape LDX.
Due to its flexible output diameter, the a|VariColl is the ideal collimator for shifting the working range of the a|TopShape LDX. For more information, see Fiber Collimation & Fiber Coupling.
Covered wavelength range of the laser beamformer a|TopShape for design wavelengths of [nm] 355, 632, and 1064 and a|TopShape LD and LDX for design wavelengths of [nm] 355, 405, 532, 632, 780, and 1064.

Beam shaping has an important role to play, e.g. in applications in laser material processing or microscopy. Gaussian profiles are usually used in laser applications. They have weaknesses regarding the distribution of their intensity. With homogeneous intensity distributions, so-called Top-Hats, significantly better results can be achieved than with Gaussian profiles. They enable, for example, a high edge steepness of the laser beam and thus the quality of the cutting edge or an even illumination. Benefit from easy handling for your application! Convert Gaussian laser profiles into collimated or focused Top-Hat intensity distributions with asphericon’s beam shapers.
Quantitative analyses in laser-based wide-field fluorescence microscopy can be very challenging if based on unevenly illuminated Gaussian beam profiles. Using the a|TopShape can help in this case. A transformation of the Gaussian beams within the microscopy set-up into homogeneous Flat-Top profiles ensures a uniform illumination of the microscope slide and thus images, which are easier to read.
Learn more about the use of the a|TopShape in wide-field fluorescence microscopy in a paper by I. Khaw et. al. from CREOL, which is available for download here
Beam shaping optics for generating collimated Top-Hats directly from stock.

a|AiryShape
Another beam shaper optimized for wavelengths from 300 nm up to 1600 nm is the a|AiryShape. This beam shaping element enables in combination with a focusing lens the transformation of collimated Gaussian beams into different focused beam profiles (e.g. Top-Hat, Donut). Thanks to its compact design, the a|AiryShape can be easily integrated into existing set-ups.
- Generation of different beam profiles
- Profile size easily scalable by focal length
- Optimized for wavelengths from 300 nm to 1600 nm
- Easy integration into existing set-ups
- Perfect alignment by high-precision mounting
- Compact design
- Input beam diameter @ 1/e2 = 10 mm; output beam diameter dAiry = 10 mm
- Laser induced damage threshold: 12 J/cm², 100 Hz, 6 ns, 532 nm
In the figure below normalized beam profile sections along its propagation direction (z-axis) are summarized in one diagram. The detected range is ± 1.5 mm around the waist location. Furthermore, the corresponding most interesting intensity profiles in the different working planes are shown as 2D and cross-sectional plots. Both plots of the characteristic beam profiles are generated with the a|AiryShape (λ = 635 nm). According to the working principle of the a|AiryShape, it is possible, not just to generate one Top-Hat beam profile in the focal plane of a focusing lens but also to create various profiles in different working distances for your flexibility. The generation of the shown beam profiles depends on the input beam quality. For optimum results a perfect collimated beam with minimized wavefront aberrations is required.

Based on the BeamTuning elements the AiryShape covers a wide wavelength range for your challenging application.

In addition to optimizing the laser and processing parameters, the adaptation of the focal intensity distribution offers great potential for high-precision results in laser material processing. In cooperation with the Otto Schott Institute of Materials Research (OSIM) in Jena, asphericon has analyzed various tailored intensity distributions, generated with the a|AiryShape, with regard to their suitability for material processing with femtosecond lasers on micro- and nanoscales, such as cutting, marking and generation of laser-induced periodic surface structures. All results are available for download in a paper by A. Möhl et. al.

Compact beam shapers for focused Top-Hat profiles in our webshop

a|SqAiryShape
Want to create squared Top-Hat profiles in the focus? No problem with the a|SqAiryShape. The newest beam shaper from asphericon generates in combination with a focusing lens different squared focused beam profiles (e.g. Top-Hat, Donut) from collimated Gaussian beams. Optimized for the wavelength range from 300 nm to 1600 nm, this beam shaper also impresses with its compact design (only 17.3 mm in length) and can be easily incorporated into existing application set-ups. Its working distance can be extremely reduced depending on the focusing lens used. Integrating an a|SqAiryShape together with a lens of 200 mm focal length and an a|BeamExpander already reduces the total length by 25%.
- Generation of different squared beam profiles
- Profile size easily scalable by focal length
- Optimized for wavelengths from 300 nm to 1600 nm
- Easy integration into existing set-ups
- Perfect alignment by high-precision mounting
- Input beam diameter @ 1/e2 = 10 mm; output beam diameter dAiry = 10 mm
- Laser induced damage threshold: 12 J/cm², 100 Hz, 6 ns, 532 nm
The following figure shows beam profile cross sections of the a|SqAiryShape (λ = 1064nm), as well as its intensity profiles in the different working planes. Due to the working principle of the a|SqAiryShape, not only one sqaured Top-Hat profile is generated in the focal region, but a variety of profiles with four-fold symmetry. The generation of all shown beam profiles from the a|SqAiryShape depends on the input beam quality. For optimum results a perfect collimated beam with minimized wavefront aberrations is required.

Based on the BeamTuning elements the a|SqAiryShape covers a wide wavelength range for your challenging application.

Compact beam shapers for round and squared focused Top-Hat profiles in our webshop
- a|BeamBox to generate collimated Top-Hat beams
- Combines up to five a|BeamExpanders, a|TopShape and a|AspheriColl with matching a|Adapters and MountedOptics
- Design wavelengths: 355 nm, 632 nm and 1064 nm
- Application: metrology, microscopy
- a|BeamBox to generate collimated Top-Hat beams
- Combines up to five a|BeamExpanders, a|TopShape and a|AspheriColl with matching a|Adapters and MountedOptics
- Design wavelengths: 355 nm, 632 nm and 1064 nm
- Application: metrology, microscopy
Combine a|BeamExpander, a|Waveλdapt, a|TopShape, a|AiryShape and a|AspheriColl with a|Adapters (intra-system and cross-system) and MountedOptics individually to suit your requirements. Almost every combination of products is possible! Please contact us.
Aspheric laser beam shapers and beam expanders from asphericon

Surface functionalization (LIPSS) with tailored focal intensity distributions
Customer Reference
Project Details
Gaussian intensity distributions are often used to structure surfaces but have weaknesses regarding their quality. The intensity decreases towards the edge and causes inhomogeneities. In cooperation with the Otto Schott Institute for Materials Research (OSIM) in Jena, asphericon analyzed the effect of Top-Hat intensity distributions generated with the beam shaper a|AiryShape regarding their suitability for the generation of laser-induced periodic surface structures (LIPSS) on stainless steel.
Project Realization
- Compact beam shaper for generating a focused Top-Hat beam
- Doubling the scanning velocity
- Reduction of the processing time by a factor of 2 with constant quality of surface pattern

Improving laser material processing with beam shaping
Customer Reference
Project Details
Although Gaussian intensity distributions can be used to realize small structure sizes by direct material removal, there are weaknesses with respect to removal depth and quality. Due to the shape of the profile, the intensity decreases at the edges of the beam and causes inhomogeneous ablation. In cooperation with Otto Schott Institute for Materials Research (OSIM) in Jena, asphericon analyzed different intensity distributions (e.g. Top-Hat, Donut) regarding their suitability for material processing with femtosecond lasers in the micro and nano range.
Project Realization
- Compact beam shaper for generating different focused beam profiles (Top-Hat, Donut, Beam waist) in various working planes
- Enlargement of channel widths and smaller ablation depths due to a more homogeneous distribution of the pulse energy on a larger area

Beam shaping optics for optimized laser welding
Customer Reference
Project Details
Additive manufacturing processes, such as powder-bed-based melting, are becoming increasingly popular to produce complex components with high degree of automation. Thanks to precise laser beam guidance, they enable a layer-by-layer, flexible structure, e.g. of cooling channels or binomial structures. However, the limiting factor here is time. Hybrid processes combine less complex, conventionally manufactured structures with intricate, additive structures created by laser welding. Among others, this type of manufacturing is used at ifw Jena. In close cooperation with asphericon, BeamTuning products were utilized here to create homogeneous weld seams to optimize beam shaping in the focus.
Project Realization
- Integration of a|BeamExpander (for beam expansion) and a|AiryShape (generation of different focused profiles, e.g. Top-Hat, Donut) into existing system technology
- Improvement of process stability as well as outgassing behavior for generation of high-quality, pore-free and gas-tight weld seams (without edge/root notches)
- Reduction of spattering and the production time

Beam shaper for fluorescence imaging
Customer Reference
Project Details
Quantitative analyses in quantitative laser-based wide-field fluorescence microscopy are highly challenging because of the uneven illumination of the slides by Gaussian profiles. The uneven illumination leads to an irregular activation of the molecules (the further from the center of the illumination, the lower the fluorescence) and stitched images lose their validity due to darkened borders. The College of Optics and Photonics at the University of Central Florida (CREOL) worked on the further development of a laser-based microscope set-up for uniform illumination using beam shaping elements. asphericon provided the beam shapers a|TopShape and a|BeamExpander.
Project Realisation
- a|TopShape and a|BeamExpander enable Gaussian beams to be transformed into flat-top profiles, thus ensuring uniform illumination of the microscope slide
- Homogeneity of illumination: > 95%
Precise optical modules for different applications – asphericon BeamTuning
Discover the unlimited combination possibilities of a|TopShape and a|AiryShape with other BeamTuning elements – including perfect fiber coupling laser solutions. Necessary flexibility is provided by a|Adapters – a combination with other systems (e.g. Owis, Edmund Optics, Qioptiq) is easily possible. Use a|BeamExpander and MountedOptics to expand the beam or shorten the working distance for your laser application. Both beam shapers are available in various combinations as practical and price-optimized a|BeamBox.
Information about available wavelengths and coatings can be found in our webshop. Here you will also find the matching, in-stock focusing lenses for the a|AiryShape as well as other readily available optics.
asphericon GmbH
Stockholmer Str. 9
07747 Jena
phone +49 (0) 3641 3100 500
fax +49 (0) 3641 3100 501
sales[at]asphericon.com