ITAR registered and ROHS & REACH compliant

ISO 9001:2015 certification
View or download:

ANAB and RvA

Large Optical Flats

Precision Optical has greatly expanded its ability to manufacture large optical flats.  With a gradual increase in necessary equipment and metrology, we have gone from manufacturing 6” lambda/20 surfaces to 24” lambda/20 surfaces.  Also, with our ability to design and build our own polishing laps, we have greatly increased our polishing capacity to yield high-efficiency output, while maintaining extremely accurate surface forms and tolerances.

Standard large optical flats sizes can yield 200mm, 300mm, 450mm and 600mm optical apertures.  Being a custom shop, we can manufacture any size in between and can offer sizes up to 850mm.  Large optical flats are required for many HEL applications, where pristine optical surfaces are essential for high laser power fluency.

Along with the challenges associated with fabrication of large optical flats, also comes the challenge of proper interferometric inspection. Precision Optical utilizes custom digital tip/tilt hardware, air bearing lateral motion, sling suspension, and proper mounting techniques to ensure precise measurements. With three-flat inspection (absolute calibration), homogeneity inspection, repeatability and standard deviation analysis, and large aperture inspection, Precision Optical can produce some of the highest end large optical flats available in the market.

Our coating chambers are configured to handle large optical flats up to 660mm diameter. Coating capabilities include laser line, broadband and multi-band anti-reflection coatings, dielectric mirrors with high laser damage resistance, and plasma or ion enhanced dielectric coatings with excellent thermal stability. We also offer protected/enhanced aluminum and silver mirror coatings and neutral density filters.

Get a Quote for Large Optical Flats

Typical Specifications

  • Material: N-BK7, Fused Silica, Zerodur, Supremax, Custom
  • Sizes: 250mm to 750mm
  • Dimensional Tolerances: ± 0.1mm to ± 1.0mm
  • Clear Aperture Types: circular, square, custom
  • Clear Aperture Sizes: up to 90% of edge dimension / surface area (typical)
  • Surface Quality: Per MIL-PRF-13830_B; ANSI/OEOSC OP1.002-2009; ISO 10110
  • Edge Chamfers: 1.0mm – 3.0mm face width or custom
  • Edge Finish: 220 grit or finer
  • Surface Flatness: λ/40 – λ/2 @ 632.8nm (size & material dependent)
  • Transmitted Wavefront: λ/20 – λ @ 632.8nm (size & material dependent)
  • Parallelism / Wedge Angle: < 1 arc second to < 1 arc minute or custom
  • Coatings: Laser line anti-reflection, broadband anti-reflection, dielectric mirrors, metal mirrors, custom coatings


Donald A. Pearson II

Äpre Instruments

I am always very happy with Precision Optical. Their lead times and delivered product are excellent. I wish more of our suppliers were like Precision Optical!

Brian Monacelli, Ph.D.

Laser Technology Professor - Pasadena City College

Partnering with Precision Optical through their Ensign-Lambert Optics Education Program has allowed over 120 of my laser and optical technology students to gain real-world perspective with hands-on work in optics. These interactions directly motivate the next generation of technicians as they learn first-hand how this fascinating work with industrial hardware will translate into rewarding careers.