Fresnel Zone Plates Discription

A Fresnel zone plate, also known as a Fresnel Phase Plate, is an optical element that utilizes the principle of light diffraction to control the phase of light waves. The surface of the phase plate is made of a series of concentric circular microstructures, whose depth and shape are precisely designed. The depth is typically related to the wavelength, forming precisely controlled stepped or relief structures. The optical path difference from any adjacent ring zones to the focal point is λ/2. This special structure ensures that light beams passing through adjacent half-wave zones arrive at the focal point with a phase difference of π. As light waves pass through, the light in different ring zones is either delayed or advanced by a specific phase amount. When the beams reach the focal point, they interfere constructively, resulting in a significantly enhanced light intensity.

Fresnel Zone Plates Product Features

Coligh is a manufacturer of Fresnel phase plates, and our Fresnel phase plates feature the following characteristics:

• We utilize micro-nano processing – photolithography and etching techniques to precisely control phase delay, thereby enhancing focusing efficiency and imaging quality.
• Our lightweight planar structure design not only reduces weight but also achieves ultra-thin profiles, making our products suitable for applications such as AR/VR wearable devices, miniature medical endoscopes, and laser systems.
• Through optimized phase structure modulation depth design, we can achieve continuous blazed profiles or high-precision multi-step fabrication. Our Fresnel phase plates deliver exceptional transmittance and diffraction efficiency.
• We support customization for multiple wavelength bands, primarily focusing on ultraviolet (UV), visible, near-infrared (NIR), and infrared (IR) bands.
• All parameters are customizable, including focal length, aperture size, and structural configuration.
  We support small-batch deliveries, and with our mature manufacturing processes, we are also capable of high-volume production.
• We offer rapid delivery capabilities, with all custom orders delivered within 4 weeks.

Coligh’s Core Advantage Of Fresnel Zone Plates

• We possess independent phase function design capabilities, supporting multi-level phase optimization and continuous phase modeling, as well as the structural fabrication of both multi-level and continuous phases.
• We have foundational optical design capabilities, enabling diffraction efficiency simulation and optimization of energy distribution.
• From small apertures to large areas, our micro-nano processing technology allows for high consistency in large-area structural control.
• From design verification to mass production, we can conduct phase accuracy interference testing, microstructural morphology measurement, and spot quality assessment, with full traceability throughout the quality process.

Coligh Fresnel Phase Plate Custom Capability

Fresnel Zone Plates Application

• AR/VR Wearable Devices
  Fresnel phase plates utilize a planar structure, which can fold the optical path while correcting chromatic aberrations through phase modulation. They can be integrated into optical waveguides as in-coupling and out-coupling elements. The microstructured surface directly modulates the angle and phase of the light from the display source, projecting a virtual image onto the user’s retina.
• Miniature Medical Endoscopes
  Medical endoscopes require high-resolution imaging within an extremely small physical space. Fresnel phase plates can replace complex optical components by being fabricated directly onto the fiber end facet or a miniature CMOS sensor, where they converge or shape the light.
• Laser Material Processing
  Applications such as laser cutting, welding, and marking often require converting a Gaussian beam into a spot with a specific energy distribution. Fresnel phase plates, through their precise stepped or multi-level structures, can reshape the laser wavefront to form a pre-designed intensity distribution at the focal plane.