In this Letter, a Gabor superlens with variable focus is presented. This configuration uses tunable liquid lenses in the third microlens array of the Gabor superlens. By applying voltage, the radius of curvature of the micro-tunable doublet arrays changes, and the Gabor conditions are fulfilled at different focal planes. As a consequence, the magnification of the image at the focal planes changes, and a zoom effect is observed. The marginal depth plane for this system goes from 0.86 to 0.89 mm. The optical simulation, calculations, and results of the simulated optical system performance are presented.

A double-zone aspheric diffractive intraocular lens (IOL) was designed and manufactured aiming to regain a continuous range of clear vision for pseudophakic presbyopia. After obtaining the IOL structure parameters through optimization based on an aphakic model eye, its imaging performances were analyzed in the model eye. The modulation transfer function at 50 cycles/mm remained above 0.29 within ±5° field of view for object distance ranging from 6 to 0.66 m. In addition, the imaging qualities are robust for pupil changes, polychromatic light, and different corneal asphericities. The manufactured IOL exhibits the ability to extend depth of focus.

We have proposed and developed a design method of a freeform surfaces (FFSs) based hyper-numerical-aperture deep ultraviolet (DUV) projection objective (PO) with low aberration. With an aspheric initial configuration, lens-form parameters were used to determine the best position to remove elements and insert FFSs. The designed FFSs PO reduced two elements without increasing the total thickness of the glass materials. Compared with aspheric initial configuration, the wavefront error of the FFSs PO decreased from 0.006λ to 0.005λ, the distortion reduced from 1 to 0.5 nm, and the aspheric departure decreased from 1.7 to 1.35 mm. The results show that the design method of the FFSs PO is efficient and has improved the imaging performance of PO. The design method of FFSs PO provides potential solutions for DUV lithography with low aberrations at 10–5 nm nodes.

A Schwarzschild microscope with a numerical aperture of 0.2 and a magnification of 130 in a 100 μm field of view (FOV) is designed and is working at 13.5 nm. Meanwhile, a CCD is used as a detector with a pixel size of 13 μm×13 μm and imaging area of 13 mm×13 mm. The imaging quality with tolerances of system and errors of mirrors are considered. We obtain that the best on-axes object resolution can be up to about 200 nm, the average value is 230 nm, and the resolution is about 360 nm at 80 μm FOV.

In this Letter, we present a novel design method of image-side telecentric freeform imaging systems. The freeform surfaces in the system can be generated using a point-by-point design approach starting from an initial system consisting of simple planes. The proposed method considers both the desired object–image relationships and the telecentricity at the image-side during the design process. The system generated by this method can be taken as a good starting point for further optimization. To demonstrate the benefit and feasibility of our method, we design two freeform off-axis three-mirror image-side telecentric imaging systems in the visible band. The systems operate at F/1.9 with a 30 mm entrance pupil diameter and 5° diagonal field-of-view. The modulation-transfer-function curves are above 0.69 at 100 lps/mm.