Fig. 1. Scatterer and meta-optics design and simulation. (a) Schematic of h=633  nm thick SiN square posts on a silicon oxide substrate. The periodicity p is kept constant, and the width w is changed to cover the whole 0−2π phase. (b) Magnitude and phase of the transmitted light for a plane wave input with p=350  nm. (c) and (d) are simulated PSFs of the EDOF meta-optic at object distances of 3.5 mm and 14.5 mm, respectively. (e) Correlation plot of simulated PSF against the PSF at the central focal point for a cubic meta-optic and a conventional metalens. The correlation clearly shows the extension of the depth of focus.

Fig. 2. Images of the fabricated meta-optics. The meta-optic was sputter coated with gold-palladium alloy to ensure charge dissipation during imaging. (a) Optical image (scale bar is 150 μm) shows that the fabricated meta-optic is not centrosymmetric. (b) Scanning electron micrograph; scale bar of 1 μm taken at 45° to the normal.

Fig. 3. (a) Setup for PSF measurement. (b) Image of 25 μm pinhole. Image and object plane sweep. Illumination is using a 530 nm LED with 33 nm bandwidth.

Fig. 4. (a) Image of the airforce resolution chart for different image and object planes. The object distance is the separation between the transparency and the meta-optic while the image distance is the distance between the meta-optic and the camera. The object is illuminated via a 530 nm LED with 33 nm bandwidth (full width at half-maximum). (b) Linecut of the air force chart (for object distance of 9.3 mm and image distance of 13.1 mm) to estimate resolution: first column is for horizontal lines, and second column is for vertical lines. Top to bottom rows, group 5, number 4–6 for the airforce resolution chart.

Fig. 5. (a) Metasurface optic integrated with E-con Systems camera module. (b) Pictures of QR code object at differing object lengths taken by a singlet refractive lens with focal length 6 mm at F/2 (left) and by a singlet EDOF meta-optic with nominal focal length 5.6 mm at F/2.8 (right). The 13 mm and 25 mm object distances used a 5  mm×5  mm QR code. The 50 mm object distance used a 10  mm×10  mm QR code, and the 80 mm object distance used a 30  mm×30  mm barcode.