LARGE OPTICS for high-energy lasers
Large optics such as mirrors and lenses are essential for long-distance projection, large-area light collection and high-energy laser facilities. The intensity of the beam in the highest power laser systems means that large optics are the most practical means of ensuring components do not suffer damage, allowing the accuracy and consistency of transmissivity and reflectivity to be assured.
The primary manufacturing challenge is controlling the surface figure across such a large area. The optic’s own weight can cause deformations during processing, while high-energy applications demand strict control over laser induced damage thresholds (LIDT) and wavefront quality.
At Manx Precision Optics, we specialise in the unique fabrication and metrology processes that large-format optics demand. Our expertise spans advanced polishing, specialised handling and long-duration uniform coating runs. We deliver large optics up to 500mm in diameter (or rectangular shapes fitting within this) with superior wavefront control, low scatter and minimal absorption for the most demanding research and industrial applications.
Manufacturing Capabilities
We design and manufacture large optics in-house, utilising a process designed to eliminate the common failure points in large-aperture components.
- Pre-coating compensatory polishing: We characterise the coating stress beforehand and polish the substrate to a specific inverse figure. This ensures that once the coating is applied, the stress pulls the optic into a perfectly flat state.
- Mid-spatial frequency (MSF) control: Our polishing techniques are optimised to minimise MSF errors (ripple), which is significant for preventing beam modulation and self-focusing in high-peak-power systems.
- High-LIDT coatings: We apply highly uniform dielectric or metallic coatings across large surface areas without compromising the damage threshold.
Technical Specifications
- Size and dimension: Manufacturing of optics up to 500mm in diameter (or equivalent rectangular footprints).
- Material selection: Expertise in working with large substrates such as Zerodur®, fused silica and N-BK7.
- Superior wavefront error: Advanced polishing to achieve excellent surface flatness (e.g. λ10 or better depending on size).
- Metrology: Verified using large-aperture interferometry to ensure the full clear aperture meets specifications.
Applications
- Beam directing for high-energy laser facilities
- Telescope mirrors (primary and secondary)
- Satellite and aerial imaging systems
- Large-scale interferometry
- Environmental and atmospheric sensing
Discuss Your Large Optics Project
Contact our technical team to discuss your specific aperture, substrate and coating requirements.
Frequently Asked Questions
Q What is the primary challenge in manufacturing large optics?
A The main challenge is controlling the surface figure (the shape and flatness) across a very large area. The optic’s own weight can cause it to deform during polishing and measurement, requiring specialised support systems and advanced metrology techniques to ensure accuracy.
Q What is Mid-Spatial Frequency (MSF) error and why does it matter?
A MSF error refers to surface ripples that are smaller than the overall form error but larger than surface roughness. In high-energy lasers, MSF errors can cause the beam to break up or modulate, potentially leading to intensity spikes that damage downstream components. We specifically polish to minimise these errors.
Q Why are large optics necessary for high-energy laser systems?
A High-power beams are often expanded to distribute the energy over a wider area. This reduces the fluence (energy density) on the optical surface, ensuring it remains below the laser induced damage threshold (LIDT) to prevent coating failure or substrate damage.