Phase Correction and Diffractive Optical Elements - Isis Project No 2369

Research at the University of Oxford’s Department of Engineering Science has resulted in a new method for producing high quality phase correction and diffractive optical elements, for a fraction of the cost of existing manufacturing methods.

Background

A normal ”optical window” has flat surfaces and uniform optical properties to ensure that a light wave transmitted through the window does not get distorted, unlike a lens for example, that modifies a light wave by focusing it at a certain point. Phase correction or diffractive optical elements (DOEs) also change the “shape” of the light waves that pass through them, however using a different method to a normal lens. DOEs have either a surface micro-relief (tiny difference in thickness) and/or non-uniform optical properties (different refractive indexes), which are designed to modify the “shape” of any light passing through it in a controlled manner. A DOE appears to be a thin, flat window, but can reproduce the effects of many large lenses and can produce other unique optical effects.

DOEs can be used with any type of lens system, however currently they are too expensive to be used in mass consumer markets due to the costs of manufacture. Their use is restricted to high value applications, where they are used to correct aberrations in laser beams, or to shape laser beams into extended shapes/multiple beams. These processes are used in imaging instruments, metrology, and laser materials processing, as well as many other specialist applications.

The technology developed at the University of Oxford opens up host of new potential markets, by providing a method of producing inexpensive and high quality DOEs

Market Opportunity

Current techniques used to manufacture high quality phase correction and DOEs are based on producing a fine surface-relief structure on one side of an optical window. This surface-relief structure is very fine, accurate on the micron scale, and is commonly produced by diamond turning or reactive ion etching. Both of these techniques are time consuming and very expensive, and consequently the use of these optical elements is limited. Plastic elements can be produced cheaply by the replication of etched elements, however these plastic elements are normally of poor quality and therefore their usefulness is also limited.

The Oxford Invention

The Oxford invention makes it possible to produce high quality optical components at a fraction of the cost of existing technologies.

Commercial Opportunity and Patent Status   

  

This invention is now the subject of a patent application. Companies interested in developing this system for commercial applications are invited to contact Isis Innovation to discuss  this further.

Request Further Information: Project Number 2369 - Phase Correction and Diffractive Optical Elements