OPTICAL DESIGN FOR BEAM SHAPING

Laser Beam Engineering

Gaussian to Top Hat Illumination

Use of customized acylindrical lensing allows for creation of Top Hat projections with the highest uniformity and efficiency available on the market. The beam shaping can be tailored for specific laser input beam characteristics for maximum repeatability and performance. The refractive based technology has > 98% efficiency and transmission, with capabilities to create micron size Top Hat dimensions. Fiber coupled solutions are also available.  

Gaussian to Top Hat Illumination

Fiber Coupled and Free-Space Gaussian to Top Hat beam shaper technical graphic
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Uniform laser line

Uniform intensity over the line length is a must for many machine vision and bioinstrumentation applications. Compared to other line generators such a cylindrical lenses and micro lens array, the Osela single line and multi lines products are based on refractive field mapping. This technology provides the best uniformity without high ripple noise and can be readily optimized for safety class. 

Uniform laser line

Intensity distribution graph for uniform laser line
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Diffractive Optics Technology

Diffractive optics allow lasers to project very complex and precise patterns when done correctly. Patterns such as multi-line, multi-dot and pseudo-random matrixes can be customized for different features and fields of view. Our patented in-house design techniques allow for high uniformity and efficiency for a wide range of wavelengths and beam characteristics. 

Diffractive Optics Technology

Graphic showing the uniformity performance of a 19 feature structured light pattern
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Focusing and Depth of Field

In the world of 3D imaging, one of the most important characteristics of the illumination is the focusing performance and its related depth of field. Osela offers 10+ different focusing options that can be tailored for the optical requirements of a specific system. We have developed setups that allow to highly characterize the laser beam, allowing for optical parameters such as Gaussian fit to be optimized over customer’s working distance and working range.

To find the right focusing configuration for your needs, please call us for access to our Online Laser Beam Simulator. 

Focusing and Depth of Field

Representation of laser line performance and characterization at focus, near field, and far field in a machine vision application
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Straightness

Line straightness is an important parameter for many 3D machine vision applications. Straightness can be defined as the deviation of the centroid of the laser line along its length. Osela’s capability to measure and characterize straightness aids our customers to optimize their vision systems for high accuracy. Our designed platforms and in-house manufacturing techniques gives us ultimate flexibility to optimize and control the straightness specification precisely, including profiles with specific degrees of polynomial for easier software compensation.

Straightness

Laser line straightness deviation graph
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Telecentric laser projection

Telecentric laser lines provide many advantages for high accuracy machine vision applications. The collimated nature of the laser line reduces potential object occlusion on an image plane (shadowing), allowing for maximum data acquisition. Osela’s TLP technology also creates uniform line thickness distribution down to micron levels for highest resolution. Hypocentric laser lines are also available to increase scattering performance for highly reflective materials. 

Telecentric laser projection

Comparison of standard Fan Angle laser vs Telecentric Laser Projection designed to mitigate occlusions
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Field corrector

Standard laser line projections often create an uneven line thickness distribution from center to edge (bowtie effect). To overcome this issue, Osela has developed field corrector optics that maintains an even line thickness throughout its length. The small form factor of this corrector option allow for ease of integration into our Compact and Streamline platforms.

Field corrector

Round beam

Osela has developed a unique beam shaping technology to create circularized laser beams over long working ranges without compromizing on beam quality. This technology allows for maintaining a high Gaussian fit and no secondary lobes that are typically found with direct diode lasers. Our in-house optical manufacturing capabilities allow us the flexibility to customize the beam parameters to fit specific system requirements.

Round beam

Graphical representation of True Gaussian Laser Intensity distribution
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Clean beam

Laser beam propagation from direct diode lasers often creates unwanted secondary lobes. To overcome this issue, Osela has developed a clean beam technology, which propagates the beam with a high Gaussian fit, suppressing any side lobes. This technology can be expanded into our laser line platforms, for optimizing focusing performance.

Clean beam

True Gaussian technology integrated with laser line projection over working range
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Cosine Correction

The advantage Osela’s in-house optical manufacturing capability allows for maximum flexibility in creating custom laser line power profiles. For applications that require edge of image field compensation, cosine corrected power distributions can be precisely specified and manufactured for optimal illumination on cameras in varied fields of view. 

Cosine Correction

Graphical representation of laser line intensity distributions with difference Cosine Corrections
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