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Abstract Printable structural colors, originating from the interaction of light with micro- and nanostructures, have emerged as a promising approach for creating vibrant, durable, and environmentally friendly coloration. The mechanisms of natural structural colors are introduced. Current printing techniques, including nozzle-based and light-based methods, are discussed, along with their respective color generation strategies. These strategies are categorized into three main approaches: nanostructure self-assembly, high-resolution printing, and total reflection interfaces. Additionally, this review addresses the current challenges within the field for each strategy and proposes potential future directions for the development of printable structural colors. Graphical abstract
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Backscatter multiple wavelength digital holography for color micro-particle imaging
This work applies digital holography to image stationary micro-particles in color. The approach involves a Michelson interferometer to mix reference light with the weak intensity light backscattered from a distribution of particles. To enable color images, three wavelengths are used, 430, 532, and 633 nm, as primary light sources. Three separate backscattered holograms are recorded simultaneously, one for each wavelength, which are resolved without spectral cross talk using a three-CMOS prism sensor. Fresnel diffraction theory is used to render monochrome images from each hologram. The images are then combined via additive color mixing with red, green, and blue as the primary colors. The result is a color image similar in appearance to that obtained with a conventional microscope in white-light epi-illumination mode. A variety of colored polyethylene micro-spheres and nonspherical dust particles demonstrate the feasibility of the approach and illustrate the effect of simple speckle-noise suppression and white balance methods. Finally, a chromaticity analysis is applied that is capable of differentiating particles of different colors in a quantitative and objective manner.
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- Award ID(s):
- 2107715
- PAR ID:
- 10306766
- Publisher / Repository:
- Optical Society of America
- Date Published:
- Journal Name:
- Applied Optics
- Volume:
- 61
- Issue:
- 5
- ISSN:
- 1559-128X; APOPAI
- Format(s):
- Medium: X Size: Article No. B83
- Size(s):
- Article No. B83
- Sponsoring Org:
- National Science Foundation
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