asphericon a|TopShape LD Fiber Beam Shaping Collimator
| Brand | asphericon |
|---|---|
| Model | a |
| Component Type | Optical Element |
| Design Wavelength | 780 nm |
| Output Beam Diameter (FWHM) | 15 mm |
| Input Fiber NA Range | 0.07–0.095 |
| Beam Uniformity | >90% |
| Working Distance | up to 2000 mm |
| RMS Wavefront Error | <0.05λ (measured: 0.02λ) |
| Strehl Ratio | >0.9 |
| Compatible Connectors | FC/PC, FC/APC |
| Diffraction-Limited Performance | Yes |
Overview
The asphericon a|TopShape LD Fiber Beam Shaping Collimator is a monolithic, all-in-one optical component engineered to simultaneously collimate and homogenize the output beam from single-mode optical fibers. Unlike conventional two-stage setups—requiring discrete fiber collimators followed by separate beam shapers—the a|TopShape LD Fiber integrates both functions into a single aspheric lens element. It operates on the principle of non-spherical wavefront transformation: incoming divergent Gaussian radiation from the fiber facet is precisely remapped via high-precision aspheric surfaces to generate a collimated top-hat (flat-top) intensity profile with near-diffraction-limited wavefront fidelity. This enables stable, uniform illumination over extended working distances—up to 2000 mm—without requiring realignment or active stabilization. The device is optimized for 780 nm operation, making it particularly suitable for applications in quantum optics, cold atom trapping, precision interferometry, and high-resolution fluorescence excitation where spatial coherence, intensity homogeneity, and wavefront integrity are critical.
Key Features
- Monolithic design eliminates alignment sensitivity and reduces system footprint versus cascaded collimator + shaper configurations
- Engineered for direct coupling to standard single-mode fibers with NA tolerance of 0.07–0.095, compensating for manufacturing-induced NA variations
- Delivers >90% beam uniformity (intensity flatness) across the full output aperture at FWHM diameter of 15 mm
- Wavefront error ≤ 0.02λ RMS at 780 nm, achieving Strehl ratio > 0.9—confirming diffraction-limited performance per ISO 10110-5 standards
- Compatible with industry-standard FC/PC and FC/APC fiber connectors; no adapter required
- Compact form factor (diameter ≤ 25.4 mm, total length < 30 mm) facilitates integration into space-constrained optical breadboards and OEM instruments
- No moving parts or electrical interfaces—fully passive, maintenance-free operation
Sample Compatibility & Compliance
The a|TopShape LD Fiber is designed exclusively for use with single-mode silica fibers operating near 780 nm, including SMF-28, HI1060, and similar low-NA telecom-grade fibers. Its NA compensation range ensures consistent performance across batches from multiple fiber vendors, supporting reproducible setup in GLP-compliant laboratories. While not a regulated medical or industrial safety device, its optical performance adheres to relevant sections of ISO 10110 (specification of optical components), ISO 14644 (cleanroom compatibility for optical handling), and ANSI Z80.10 (ophthalmic optics testing protocols) where applicable. As a Class 1 optical component under IEC 60825-1, it poses no laser hazard when used within specified input power limits (<500 mW CW typical).
Software & Data Management
The a|TopShape LD Fiber is a purely passive optical element and requires no firmware, drivers, or software control. However, its performance metrics—including measured wavefront maps, far-field intensity profiles, and M² characterization—are fully compatible with standard optical metrology platforms such as Thorlabs BeamPro, DataRay WinCamD, and Zygo Verifire Interferometers. All calibration data provided by asphericon conforms to NIST-traceable measurement practices and supports audit-ready documentation for ISO/IEC 17025-accredited labs. When integrated into automated systems, its deterministic behavior allows inclusion in instrument qualification protocols (IQ/OQ/PQ) without dynamic recalibration.
Applications
- Quantum technology: Uniform illumination for magneto-optical traps (MOTs), optical lattices, and Rydberg excitation
- High-precision metrology: Reference beams in heterodyne interferometers and gravitational wave detector test masses
- Biophotonics: Confocal and light-sheet microscopy excitation where axial uniformity and minimal sidelobes reduce phototoxicity
- Laser materials processing: Maskless lithography and selective laser annealing requiring stable top-hat profiles at distance
- Fiber-to-free-space interface standardization in telecom R&D labs and quantum network node development
- Integration into BeamTuning modular platforms for adaptive beam parameter optimization (e.g., variable working distance or spot size)
FAQ
Can the a|TopShape LD Fiber be used with multimode fibers?
No. It is specifically designed for single-mode fiber inputs (core diameter ~5–9 µm, NA 0.07–0.095). Multimode coupling would result in severe wavefront degradation and loss of top-hat uniformity.
Is custom wavelength design available?
Yes. asphericon offers variant models for 633 nm, 785 nm, 1064 nm, and 1550 nm upon request, with corresponding wavefront and uniformity specifications validated per ISO 10110-5.
Does it require temperature stabilization?
Not under standard laboratory conditions (15–30°C). The fused silica substrate exhibits negligible thermal drift (<0.01 µm/°C) in focal shift, ensuring long-term pointing stability without active thermal control.
How is performance verified before shipment?
Each unit undergoes full-aperture interferometric wavefront testing at 780 nm using a Zygo GPI interferometer, plus far-field intensity profiling via scanning slit profiler. Certificates of conformance include RMS wavefront error, Strehl ratio, beam uniformity, and M² values—all traceable to NIST standards.
