DOE Customization: How Things Are Done At The Expert Level?

DOE Customization: How Things Are Done At The Expert Level?

Diffractive optical elements (DOEs) can shape and divide the laser beams in an energy-efficient way. They are useful in patterning the light in various work areas for custom illumination. In short, DOEs allow the user to control the phase across the aperture accurately and accordingly design the complicated intensity profiles.

In order to suit the specific applications of each industry, diffractive optical elements are customized by the professionals in the following ways:

  • Problem Analysis: The first step is analyzing the problem and understanding the client specifications. Many suppliers offer a wide range of off-the-shelf diffractive optical elements to fulfill the specification of each customer. They also perform proof-of-concept experiments on diffractive optical elements to accurately evaluate the specifications followed by spatial light modulator (SLM) technology to demonstrate the optical functions of DOEs.
  • Design and Simulation of DOE: In order to meet the specifications, computational design methods like Iterative Fourier Transform Algorithms (IFTA), direct binary search (DBS) algorithms, and gradient search algorithms are used. These are among the best methods to approach problems that require high-levels of complexity at a low budget.

  • Fabrication of DOEs: Choosing the right fabrication technology largely depends on two parameters: client’s specification and the volume of production.
  • Once the fabrication technology is selected, the next is these 4 steps:
  • Step 1: The design data is optimized with the aim to minimize the fabrication error dependency. For instance, if your objective is to reduce costs, then lithography technology is the best choice. Similarly, if the client needs diffractive structures with a size down to 50nm pixels, one must use E-beam direct writing lithography.
  • Step 2: After the sequential writing process, the etching technique is used to create target surface structures in the substrate material. Etching technique like iron rolling or electroplating also helps to generate tools for replication processes such as injection molding and nano-imprinting.
  • Step 3: Once the results of replication meet the specification of the client, DOEs are fabricated and assembled in the main product.

  • Quality Assurance and Implementation Support: In order to ensure that DOEs are matching with the specifications, the optic supplier personally cross-verifies the DOE post-fabrication. When the order is in bulk, the scientist monitors the key properties of DOE using automated equipment.

The process of manufacturing customized diffractive optics involves a number of complex tasks. Therefore, it’s always recommended choosing the professionals.