Diffractive optical elements (DOEs) can be used for generating complex light patterns with precisely defined dimensions in a certain plane. They shape and divide the laser beam efficiently. These micro-structured optical elements are fabricated by etching in fused silica or embossing in different polymer materials.

In general, DOEs are a complex pattern of micro- and nano-scale structures that can modulate and transform light in a predetermined way. Developers can design them to handle simultaneous tasks. With the unique properties of diffractive optics, they can realize optical functions that are otherwise hard or impossible with traditional optics. Also, they can perform the traditional optical functions of lenses, aspheres, and prisms. With DOEs generated by computers, a laser beam can be shaped into any intensity pattern like lines, circles, dot arrays, arrows, and other arbitrary pattern designed to the requirements of customers.

Benefits of DOEs

The following are the benefits of diffractive optical elements:

  • DOEs are highly précised diffraction structures made using modern production methods and top-notch manufacturing processes.
  • Energy-efficiency. The laser beams are shaped and split to control intensity.
  • Diffractive optics can be replaced or combined with refractive optics. Also, they let users control the phase across the aperture and create complicated intensity profiles.
  • DOEs can be customized to suit specific applications.

DOE Applications

DOEs can improve the value of laser systems. They have a lot of functions and are useful for various kinds of applications. For instance, they can be found in long-range distance sensors, short-range distance sensors, motion detection and projection systems, as well as position sensors.

Standard elements are available in a lot of applications; however, the microstructure can be tailored to make any pattern desired. They can be made from polycarbonate or glass for high-energy applications like laser cutting and drilling. While diffractive optical elements are used mostly with laser light, partially coherent light from LEDs and other light sources can also be manipulated.

Specific applications of DOEs include the following:

  • Biomedical devices. DOES are used for medical laser treatments and diagnostics instruments.
  • DOEs are used as beam splitters and for silicon photonics applications and wavelength selection.
  • Laser material processing. Laser beams are shaped and split during the cutting, soldering, welding, scoring, and drilling.
  • Lithography and holographic lighting. Beam homogenization is used mask projection systems, structured pupil illumination, and homogenous field illumination.
  • Optical sensors. DOEs are used as distance and position sensors and for motion detection.