Fabrication of a micro-lens array for improving depth-of-field of integral imaging 3D display

Abstract

In this paper, we present a new, to the best of our knowledge, structure of double pinhole/micro-lens array (DP/MLA) with two center-depth planes, used for improving the depth-of-field (DOF) of integral imaging (II), which can be fabricated by a combination of lithography and inkjet printing. The results show that a black circular groove array prepared by lithography can be used for micro-lens location and reduce the stray light for II. By controlling the parameters of the inkjet printing system, DP/MLA with high precision, high alignment, and good focusing ability can be achieved. When the fabricated DP/MLA is applied in the II system, the reconstructed image has a better three-dimensional (3D) image with higher DOF than that by traditional MLA and higher quality than that by ordinary double-layer MLA.

Direct Microtip Focused Electrohydrodynamic Jet Printing of Tailored Microlens Arrays on PDMS Nanofilm‐Modified Substrate

“…It can be seen that the focal length and f-number decreased from 55.59 to 9.34 µm and from 2.78 to 0.95, respectively, while the NA of MLAs was controllable increasing from 0.18 to 0.53 through different PDMS nanofilm modified substrates. The calculated f-number is 0.95 for the microlens on the T4 substrate, which is 13.6% smaller than the minimum value in previous studies using other methods, [2,42,44,45,46] as shown in Table S1 (Supporting Information). The smaller f-number indicates the enhanced light-gathering power of the MLAs with the increased resolutions of geometrical properties (smaller diameter and larger height) due to the PDMS nanofilm modification.…”

“…In recent years, microlens arrays (MLAs) have attracted extensive attention due to their wide applications in various fields such as digital displays, [ 1–3 ] light‐emitting‐diodes (LEDs), [ 4,5,6,7 ] super‐resolution imaging, [ 8,9,10 ] and artificial compound eyes. [ 11,12,13 ] The demand of MLAs with precise shaping features has increased over the last few decades.…”

“…In recent years, microlens arrays (MLAs) have attracted extensive attention due to their wide applications in various fields such as digital displays, [1][2][3] light-emitting-diodes (LEDs), [4,5,6,7] super-resolution imaging, [8,9,10] and artificial compound used to fabricate micro/nanolens arrays (M/NLAs). [13,28] Zhou et al reported that the diameters of the MLAs fabricated by E-jet printing decreased from 32.45 to 1.59 µm when the inner diameter of the nozzle decreased from 25 to 1 µm.…”

Metalens in Improving Imaging Quality: Advancements, Challenges, and Prospects for Future Display

“…Each CDP can display the image of the corresponding focal length. The distance between the two CDPs is: [134]…”

“…where b1 and b2 are the distances from lens array 1 to the central depth plane 1 and 2, respectively; d is the distance between the two lens arrays; a is the distance from the display screen to lens array 2; and f is the refractive index of the lens array. [134] Duallayer lens array with a complementary symmetrical structure can increase the number of CDP by increasing the number of layers of the lens array, to realize the function of increasing the DOF. Nanotarget.…”