Hierarchical Artificial Compound Eyes with Wide Field-of-View and Antireflection Properties Prepared by Nanotip-Focused Electrohydrodynamic Jet Printing

Curved compound eyes have generated great interest owing to the wide field of view but the application of devices is hindered for the lack of proper detectors. One-lens curved compound eyes with multi-focal microlenses provide a solution for wide field imaging integrated in a commercial photo-detector. However, it is still a challenge for manufacturing this kind of compound eye. In this paper, a rapid and accurate method is proposed by a combination of photolithography, hot embossing, soft photolithography, and gas-assisted deformation techniques. Microlens arrays with different focal lengths were firstly obtained on a polymer, and then the planar structure was converted to the curved surface. A total of 581 compound eyes with diameters ranging from 152.8 µm to 240.9 µm were successfully obtained on one curved surface within a few hours, and the field of view of the compound eyes exceeded 108°. To verify the characteristics of the fabricated compound eyes, morphology deviation was measured by a probe profile and a scanning electron microscope. The optical performance and imaging capability were also tested and analyzed. As a result, the ommatidia made up of microlenses showed not only high accuracy in morphology, but also imaging uniformity on a focal plane. This flexible massive fabrication of compound eyes indicates great potential for miniaturized imaging systems.

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Fabrication of Waterproof Artificial Compound Eyes with Variable Field of View Based on the Bioinspiration from Natural Hierarchical Micro–Nanostructures

Nano-Micro Letters ◽

10.1007/s40820-020-00499-x ◽

2020 ◽

Vol 12 (1) ◽

Cited By ~ 3

Author(s):

Peilin Zhou ◽

Haibo Yu ◽

Ya Zhong ◽

Wuhao Zou ◽

Zhidong Wang ◽

...

Keyword(s):

Field Of View ◽

Compound Eyes ◽

Water Contact ◽

Manufacturing Method ◽

Variable Field ◽

Electrohydrodynamic Jet Printing ◽

Flexible Film ◽

Superhydrophobic Property ◽

Jet Printing ◽

Novel Method

AbstractPlanar and curved microlens arrays (MLAs) are the key components of miniaturized microoptical systems. In order to meet the requirements for advanced and multipurpose applications in microoptical field, a simple manufacturing method is urgently required for fabricating MLAs with unique properties, such as waterproofness and variable field-of-view (FOV) imaging. Such properties are beneficial for the production of advanced artificial compound eyes for the significant applications in complex microcavity environments with high humidity, for instance, miniature medical endoscopy. However, the simple and effective fabrication of advanced artificial compound eyes still presents significant challenges. In this paper, bioinspired by the natural superhydrophobic surface of lotus leaf, we propose a novel method for the fabrication of waterproof artificial compound eyes. Electrohydrodynamic jet printing was used to fabricate hierarchical MLAs and nanolens arrays (NLAs) on polydimethylsiloxane film. The flexible film of MLAs hybridized with NLAs exhibited excellent superhydrophobic property with a water contact angle of 158°. The MLAs film was deformed using a microfluidics chip to create artificial compound eyes with variable FOV, which ranged from 0° to 160°.

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On the functions of double eyes in midwater animals

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.2000.0656 ◽

2000 ◽

Vol 355 (1401) ◽

pp. 1147-1150 ◽

Cited By ~ 23

Author(s):

Michael F. Land

Keyword(s):

High Resolution ◽

Field Of View ◽

Optical Systems ◽

Compound Eyes ◽

Wide Field ◽

Background Light ◽

Light Levels ◽

Wide Field Of View ◽

Silhouette Detection ◽

Luminescence Detectors

Midwater predators often have double eyes consisting of a large upward–pointing part with a narrow field of view and high resolution, and a small downward–pointing part with a wide field of view and low resolution. In crustaceans with compound eyes the different eye parts are of basically similar construction, but in fishes the downward–pointing regions may employ unusual optical systems with unknown image–forming capabilities. It has been suggested that the upward–directed parts are used to detect silhouettes of animals against the residual daylight, whereas the lower parts look out for luminescent organisms. Here I calculate the sizes that apposition compound eyes would need to attain in order to fulfil these tasks, and the way that size should vary with depth. It is concluded that silhouette detection is much the more demanding task, and becomes increasingly difficult as light levels decrease. For this reason the upward–pointing parts must increase rapidly with depth. This is not the case with luminescence detectors, where the task is most difficult near the surface because of upwelling background light, and becomes easier with depth. On the whole these predictions fit well with the sizes and shapes of real midwater eyes, especially in the case of the hyperiid amphipods.

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STM studies of crystal growth

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100086179 ◽

1991 ◽

Vol 49 ◽

pp. 374-375

Author(s):

M. G. Lagally

Keyword(s):

Crystal Growth ◽

Molecular Beam ◽

Chemical Vapor ◽

Sputter Deposition ◽

Field Of View ◽

Scanning Tunneling ◽

Wide Field ◽

Tunneling Microscopy ◽

Wide Field Of View ◽

The One

It has been recognized since the earliest days of crystal growth that kinetic processes of all Kinds control the nature of the growth. As the technology of crystal growth has become ever more refined, with the advent of such atomistic processes as molecular beam epitaxy, chemical vapor deposition, sputter deposition, and plasma enhanced techniques for the creation of “crystals” as little as one or a few atomic layers thick, multilayer structures, and novel materials combinations, the need to understand the mechanisms controlling the growth process is becoming more critical. Unfortunately, available techniques have not lent themselves well to obtaining a truly microscopic picture of such processes. Because of its atomic resolution on the one hand, and the achievable wide field of view on the other (of the order of micrometers) scanning tunneling microscopy (STM) gives us this opportunity. In this talk, we briefly review the types of growth kinetics measurements that can be made using STM. The use of STM for studies of kinetics is one of the more recent applications of what is itself still a very young field.

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