Optical Blank Fabrication

Precision Blank Fabrication

Round & Rectangular Fused Silica Optical BlanksFused silica optical blanks are used in the manufacturing of electronics, lasers, optical components, scientific instruments, semiconductors, telecom equipment, and an assortment of energy and aerospace applications. As an authorized distributor of Corning HPFS® 7980 and ULE® 7972 and 7973, Dynasil fabricates precision machined optical blanks and other components as well as from a variety of other manufacturers’ optical materials.

We invite inquiries for special sizes and shapes in any grade and in any optical material, as Dynasil offers a full spectrum of raw materials and is equipped to cut, core and fine grind precision optical blanks of virtually any shape, in prototype and production quantities. At the heart of our specialized optical component skills, are our knowledge of optical glass, our in-house capabilities to machine, test and certify our products to your requirements, as well as over fifty-five years of experience.

Optical Materials

Dynasil is an authorized distributor of:

Our products come in these standard shapes and sizes:

  • DISCS: to 16″ diameter, 4.5″ thick
  • SOLID RODS: to 4.5″ in length
  • BARS/BLOCKS: to 50″ diagonal, 11″ thick
  • CUBES: measurements available upon request


Dynasil Fused Silica’s extensive fabrication capabilities include both commercial machine tools and custom designed specialty devices:

  • Core Drilling – From 0.190 +/- 0.005 inches diameter to 16.125 +/- 0.040 inches diameter
  • Cylindrical (centerless) grinding – Up to 4 inches diameter by 12 inches in length
  • Diamond edging – Up to 18 inches diameter by 3.75 inches thick
  • Diamond sawing – Up to 39 inches by 36 inches
  • Measured beveled edges – Up to 4 inches diameter with bevels from .01 – .06 inches, 358.775 mm long rectangles measured chamfer capabilities offered
  • Surface Grinding – Up to 40 inches diameter (or diagonal) by 15 inches thick, larger sizes upon request

In-house Testing

  • Laser Fizeau Interferometer for Index Homogeneity Tests
  • UV-VIS-IR Spectrophotometer for Transmission Measurements
  • Luminance Spectrometer for Fluorescence Testing
  • Polarimeters for Strain/Striae Observation
  • Surface Profilometer

Stock Allowances, Tolerances and Finishes

Unless specifically requested, our optical blanks are created in nominal finished sizes (NFS) of the respective circles, squares, rectangles or prisms. The actual pieces supplied will be blanks that include a finishing stock allowance.

The finishing stock is +.125″ (+/-.040 maximum) on diameter. Pieces 16.5″ in diameter and over may be saw/hex/rough cut at +.125″ (+.500, -0) on diameter and +.050″ (+.125, -0) on thickness.

Centerless grinding/edging to close tolerances is available on diameters up to 18″.

Length, width, and saw cut thickness are given a finishing stock allowance of +.050″ (+.125, -0) with an 80 grit minimum finish. Blanchard ground finishes (220-320 grit) are available featuring dimensional tolerances of +/-.005″ maximum.

Optical blanks with a diameter or diagonal of less than 8.6″ and thickness less than .550″ may be I.D. saw cut with a thickness tolerance of +/-.002″ (maximum) and an exceptionally smooth (170-200 mesh), flat finish.