Diffraction International is the world leader in supplying CGH diffractive null correctors for aspheric metrology. Our 20 years of experience in the design and application of CGH nulls is unrivaled.
Our custom CGH nulls are used for testing surface figure and transmitted wavefront distortion of general asphere, toroid, and cylinder optics. They transform your interferometer's spherical or collimated test wavefront into a prescribed aspheric wavefront. Each CGH null is pre-aligned in a frame for kinematic mounting to our multi-axis positioners. We provide design, encoding, fabrication, testing, and full documentation. Our custom CGHs are also used in HOE recording. They can produce aspheric construction wavefronts, verify construction optics alignment, and null test the finished HOEs. Diffraction International's Durango Interferometry Software adds phase measuring capability to any interferometer. Durango runs under Windows XP/2000 on a desktop or laptop PC and works with virtually any interferometer hardware, commercial or shop-built. Durango supports all camera resolutions and numerous phase algorithms. Durango uses only documented non-proprietary algorithms and gives the user full control over interferogram acquisition and subsequent analysis. You may download Durango software and its sample data files from our web site. A paid license is needed only to acquire or import new data. Durango software and interferometric test data are shipped with each of our custom CGH nulls.