Large area structural color printing based on dot-matrix laser interference patterning

Optics Express, Journal Year: 2023, Volume and Issue: 31(23), P. 38610 - 38610

Published: Oct. 19, 2023

Optically Variable Devices (OVDs) are widely used as security features in anti-counterfeiting efforts. OVDs enable the display of color dynamic effects that easily interpreted by user. However, obtaining these elements over large areas poses certain challenges terms efficiency. The paper presents a modified approach for manufacturing plasmonic type through dot-matrix technology, which is standard origination step holograms. By adjusting spatial filters optical scheme, it possible to double resolution recorded quasi-sinusoidal diffraction gratings. experiments confirm creation gratings with frequencies from 1600 3500 lines per mm, facilitates production zero-order spectral filters. shows how transmission characteristics studied affected geometric parameters grating, silver layer thickness, angle incidence, and polarization light. results have shown using proposed method obtain 1D or 2D structural OVD-image on area - several square centimeters more. High speed recording such provided: exposure time was 120 400 ms depending grating 0.05 mm2 frame, total printing size 25×25 OVD about 2.5 hours element, less than 3.5 element. Thus, produced can be useful designers simpler faster alternative electron-beam lithographic technologies.

Language: Английский

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Height modulation of nanopixel arrays via light controlled capillary force lithography

Published: Jan. 1, 2024

Conventional nanotextures typically consist of arrays identical nanopixels. Recently, efforts have focused on enhancing their functionalities by introducing spatial modulation to the height distribution nanopixels for anti-reflective surface, bactericidal effects, and structure colors. However, pre-designed, non-random holds potential even greater functionalities. Many applications require precise nanometric control nanopixel as a function position. Only few methods, such grayscale photolithography, nanoimprint lithography, electron beam dip pen two-photon polymerization can meet these stringent requirements, albeit often at high cost. techniques involve chemical development processes, some rely expensive pattern generators utilizing lasers, beams, or ion beams. Consequently, there is pressing need facile reconfigurable printing methods that offer both vertical lateral resolutions without compromise. Capillary force lithography (CFL), introduced Suh et al. in 2001, represents fusion key aspects from soft combining molding polymer with use an elastomeric mold, respectively. This innovative approach preserves fidelity required while eliminating pressures associated traditional techniques. Furthermore, CFL simplifies process removing requirement steps, streamlining overall procedure. These distinctive features make attractive method producing large-area patterns nanoscale accuracy. alone cannot achieve printing, it lacks capability polymer's capillary rise predetermined precision, let position micrometer scale. In this research, we developed technique optically modulate discovered attainable certain photopolymers. The factor enabling was optical pre-modification photopolymer's properties critical rise. significant promise high-resolution, two-dimensionally patterned CFL, benefiting easily microscale patternable nature light. "freeze-framing" characteristic also provides accessible means observe analyze dynamics polymeric nanocapillary effect, phenomenon has not been fully elucidated date.

Language: Английский

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A novel method for realizing multilayer diffractive optical variable devices via oblique elliptical vibration texturing

Published: Nov. 13, 2024

Optically variable devices (OVD) are esteemed security elements renowned for their capacity to produce structural color effects reliant on multiple angle-dependent information channels. In this paper, based the patterning of single-point diamond ultrasonic oblique elliptical vibration texturing, a novel strategy micro/nano grating structure encoding multi-layer high-definition images is proposed and demonstrated. The innovation paper lies in design rotating stable bracket equipped with tool, allowing flexible adjustment tool angle generate an texture. Firstly, establishes mathematical model spatial diffraction, extending it from two-dimensional plane three-dimensional space, determines variation trend diffraction efficiency different directions within observation domain. Secondly, relationship between established via micro-optical theoretical model, so as determine mapping pixel cutting velocity. Finally, texturing used achieve ultra-fast pixel-level drawing sub-micron gratings controllable spacing. Simultaneously, deflects at set angles machine structures images. This method flexibly controls convergence direction diffracted light, thereby realizing three-layer image encoding. research results show that OVD exhibits ability selectively display target various angles, indicating decoupled.

Language: Английский

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High-performance sustainable polyester amide composites with persistent luminescence for multiple anti-counterfeiting

Chemical Engineering Journal, Journal Year: 2024, Volume and Issue: unknown, P. 159007 - 159007

Published: Dec. 1, 2024

Language: Английский

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