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This paper presents a simulation model for a large field‐of‐view, wide eye‐box, and high‐resolution ultra‐thin near‐eye display based on a freeform optical lens array. It creatively incorporates a polarization‐based optical folding technique (pancake lens), reducing the thickness of the simulation model to less than 1.4 cm (excluding the display screen). Compared to traditional VR devices, this significantly reduces the volume and weight of the equipment. The parameters of the simulation model are as follows: eye‐box size of 10mm, resolution utilization rate of 50%; the introduction of freeform optics greatly improves the imaging quality of the displayed images. At the same time, the field of view reaches 116° (single eye, vertical direction). [ABSTRACT FROM AUTHOR]

A photonic integrated interference imaging system (PIIIS) is a computational imager based on Michelson interference and photonic integrated circuits (PICs). In this paper, a PIIIS based on a compact sampling lenslet array that can sample the zero spatial frequency through a single lenslet, densely sample the frequency in the azimuth direction through the configuration of a hierarchical multistage lenslet array, and continuously sample the frequency in the radial direction through a Langford sequence is proposed. We introduce the design process of the compact sampling lenslet array in detail and simulate the imaging of the system. The simulation results demonstrate that the lenslet array can effectively improve the imaging quality of a PIIIS. In addition, we design a silicon PIC and a silicon nitride transition PIC that match the compact sampling lenslet array and simulate the imaging of the system under the influence of the on-chip optical loss of PICs (the average interference baseline loss is 15.4 dB at 1550 nm). The results show that on-chip optical loss mainly affects the brightness and contrast of the reconstructed image but has little effect on the structure. [ABSTRACT FROM AUTHOR]

We demonstrate an ultracompact virtual reality (VR) system with thickness of about 1‐cm. In this system, the imaging optics consists of a lenslet array, a deflector array, and a Pancharatnam‐Berry deflector (PBD). We have experimentally demonstrated a polarization interpolation configuration to reduce the system thickness by nearly 50%. [ABSTRACT FROM AUTHOR]

On the demand of low-cost, lightweight, miniaturized, and integrated optical systems, precision lenslet arrays are widely used. Diamond turning is often used to fabricate lenslet arrays directly or molds that are used to mold lenslet arrays. In this paper, mainly by real-time monitoring position following error for slow tool servo, different fabrication parameters are quantitatively studied and optimized for actual fabrication, then by actual fabrication validation, uniform and high-fidelity surface topography across the actual whole lenslet array is achieved. The evaluated fabrication parameters include sampling strategy, inverse time feed, arc-length, etc. The study provides a quick, effective, and detailed reference for both convex and concave lenslet array cutting parameter selection. At the end, a smooth zonal machining strategy toolpath is demonstrated for fabricating concave lenslet arrays. [ABSTRACT FROM AUTHOR]

A photonic integrated interference imaging system (PIIIS) is a computational imager based on Michelson interference and photonic integrated circuits (PICs). In this paper, a PIIIS based on a compact sampling lenslet array that can sample the zero spatial frequency through a single lenslet, densely sample the frequency in the azimuth direction through the configuration of a hierarchical multistage lenslet array, and continuously sample the frequency in the radial direction through a Langford sequence is proposed. We introduce the design process of the compact sampling lenslet array in detail and simulate the imaging of the system. The simulation results demonstrate that the lenslet array can effectively improve the imaging quality of a PIIIS. In addition, we design a silicon PIC and a silicon nitride transition PIC that match the compact sampling lenslet array and simulate the imaging of the system under the influence of the on-chip optical loss of PICs (the average interference baseline loss is 15.4 dB at 1550 nm). The results show that on-chip optical loss mainly affects the brightness and contrast of the reconstructed image but has little effect on the structure.

In the future, various types and parameters of display devices and lenslet arrays will be commercially available. Different display devices can be matched by cutting and expanding elemental images, while different lenses require changing the pixel mapping structure individually for each pixel, which involves complex calculations. A simple pseudoscopic-to-orthoscopic conversion for lenslet arrays with different apertures in real and virtual fields has meaningful practical implications. To this end, orthoscopic integral imaging for different lenslet arrays in real and virtual fields is proposed herein. The tilt-shift photography technique is used to generate a wider view image array, which is cropped to form the orthoscopic elemental image arrays required for lenslet arrays of various shapes, considering their specific structures and shapes. The approach expands the viewing angle without the need to change the system parameters or recalculate the elemental image relative to the viewer's position, enabling multiple individuals to view the three-dimensional (3D) images from different angles simultaneously. It does not require additional devices or depth information. The repositioning of the original camera array enables various display modes, such as real images, virtual images, and co-displays, which enhance the 3D display effect. The experimental results demonstrate that the proposed method can generate 3D images with correct depth relationships and large viewing angles, through subjective and quantitative comparison of the parallax. • The pseudoscopic problem in viewing 3D images effectively addressed. • A flexible method for generating orthoscopic integral images proposed. • Method applicable for different lenslet arrays in real and virtual fields. • Real, virtual, and co-displayed 3D images obtained. • Simulations and optical experiments confirmed method efficacy. [ABSTRACT FROM AUTHOR]

On the demand of low-cost, lightweight, miniaturized, and integrated optical systems, precision lenslet arrays are widely used. Diamond turning is often used to fabricate lenslet arrays directly or molds that are used to mold lenslet arrays. In this paper, mainly by real-time monitoring position following error for slow tool servo, different fabrication parameters are quantitatively studied and optimized for actual fabrication, then by actual fabrication validation, uniform and high-fidelity surface topography across the actual whole lenslet array is achieved. The evaluated fabrication parameters include sampling strategy, inverse time feed, arc-length, etc. The study provides a quick, effective, and detailed reference for both convex and concave lenslet array cutting parameter selection. At the end, a smooth zonal machining strategy toolpath is demonstrated for fabricating concave lenslet arrays.