# Multi-plane, Multi-band image projection via Broadband Diffractive Optics

## TL;DR

This paper introduces Broadband Diffractive-Optical Elements (BDOEs) capable of projecting multiple images across different spectral bands and planes, with adjustable magnification, flat and reflective designs, all under broadband illumination.

## Contribution

The work presents novel BDOEs that enable multi-plane, multi-band image projection with adjustable magnification and flat or reflective configurations, fabricated via cost-effective imprint techniques.

## Key findings

- Demonstrated different images in spectral bands and planes
- Achieved image magnification by source distance adjustment
- Developed flat and reflective BDOEs with high efficiency

## Abstract

We demonstrate visible and near-IR image projection via non-absorbing, multi-level Broadband Diffractive-Optical Elements (BDOEs) in 1 or more planes. By appropriate design of the BDOE topography, we experimentally demonstrate: (1) different images in different spectral bands; (2) different images in different image planes; (3) image magnification by changing the distance between the illumination source and the BDOE; (4) completely flat BDOE via an index-contrast top-coating; and (5) reflective BDOEs. All of these are accomplished with broadband illumination. Furthermore, the BDOEs are highly efficient, versatile and can be inexpensive mass manufactured using imprint-based replication techniques.

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Source: https://tomesphere.com/paper/1901.05943