1
|
Zhang X, Wang L, Cao XW, Jiang S, Yu YH, Xu WW, Juodkazis S, Chen QD. Single femtosecond pulse writing of a bifocal lens. OPTICS LETTERS 2024; 49:911-914. [PMID: 38359214 DOI: 10.1364/ol.515811] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2023] [Accepted: 01/15/2024] [Indexed: 02/17/2024]
Abstract
In this Letter, a method for the fabrication of bifocal lenses is presented by combining surface ablation and bulk modification in a single laser exposure followed by the wet etching processing step. The intensity of a single femtosecond laser pulse was modulated axially into two foci with a designed computer-generated hologram (CGH). Such pulse simultaneously induced an ablation region on the surface and a modified volume inside the fused silica. After etching in hydrofluoric acid (HF), the two exposed regions evolved into a bifocal lens. The area ratio (diameter) of the two lenses can be flexibly adjusted via control of the pulse energy distribution through the CGH. Besides, bifocal lenses with a center offset as well as convex lenses were obtained by a replication technique. This method simplifies the fabrication of micro-optical elements and opens a highly efficient and simple pathway for complex optical surfaces and integrated imaging systems.
Collapse
|
2
|
Cao H, Deng H, Wan H, Luan S, Shen S, Gui C. Superhydrophobic Multifocal Microlens Array with Depth-of-Field Detection for a Humid Environment. ACS OMEGA 2023; 8:48572-48581. [PMID: 38144063 PMCID: PMC10733981 DOI: 10.1021/acsomega.3c08680] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/02/2023] [Revised: 11/19/2023] [Accepted: 11/23/2023] [Indexed: 12/26/2023]
Abstract
Microlens array (MLA) has been widely applied in augmented reality and optical imaging. When used in a humid environment or medical endoscopy, MLA needs to be both superhydrophobic and multifocal. However, it is not easy to achieve both superhydrophobic and multifocal function by integrating superhydrophobic and multifocal structures on the same surface by means of a simple, efficient, and precise method. In this paper, the superhydrophobic multifocal MLA with superhydrophobic properties and multifocal functions is successfully designed for preparation based on a method of 3D lithography and soft lithography. The 3D lithography can further help the preparation of a multifocal MLA with varying apertures and a multistep superhydrophobic structure with a round dome. The superhydrophobic multifocal MLA with periods 50 and 120 μm has perfect superhydrophobic property. The water droplet can slide and bounce off the surface at a roll angle of less than 12.9° with both multifocal and integrated imaging function, as well as up to 397 μm depth-of-field (DOF) detection range; this greatly exceeds the conventional MLA. The perfect superhydrophobic and optical property can be achieved in an extremely humid environment. The superhydrophobic multifocal MLA proposed in this paper has a promising prospect for actual practices.
Collapse
Affiliation(s)
- Hao Cao
- The
Institute of Technological Sciences, Wuhan
University, Wuhan 430072, China
| | - Hongfeng Deng
- The
Institute of Technological Sciences, Wuhan
University, Wuhan 430072, China
| | - Hui Wan
- School
of Power and Mechanical Engineering, Hubei Key Laboratory of Electronic
Manufacturing and Packaging Integration, Wuhan University, Wuhan 430072, China
| | - Shiyi Luan
- The
Institute of Technological Sciences, Wuhan
University, Wuhan 430072, China
| | - Su Shen
- School
of Optoelectronic Science and Engineering, Collaborative Innovation
Center of Suzhou Nano Science and Technology, Soochow University, Suzhou 215006, China
| | - Chengqun Gui
- The
Institute of Technological Sciences, Wuhan
University, Wuhan 430072, China
| |
Collapse
|
3
|
Li J, Wang W, Fu Z, Zhu R, Huang Y. Fabrication of a dual-focus artificial compound eye with improved imaging based on modified microprinting and air-assisted deformation. APPLIED OPTICS 2023; 62:D125-D130. [PMID: 37132777 DOI: 10.1364/ao.476320] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Natural compound eyes inspire the development of artificial optical devices that feature a large field of view and fast motion detection. However, the imaging of artificial compound eyes dramatically depends on many microlenses. The single focal length of the microlens array significantly limits the actual applications of artificial optical devices, like distinguishing objects at different distances. In this study, a curved artificial compound eye for a microlens array with different focal lengths was fabricated by inkjet printing and air-assisted deformation. By adjusting the space of the microlens array, secondary microlenses were created between intervals of the primary microlens. The diameter/height of the primary and secondary microlens arrays are 75/25 µm and 30/9 µm, respectively. The planar-distributed microlens array was transformed into a curved configuration using air-assisted deformation. Compared with adjusting the curved base to distinguish objects at different distances, the reported technique features simplicity and is easy to operate. The applied air pressure can be used to tune the field of view of the artificial compound eye. The microlens arrays with different focal lengths could distinguish the objects at different distances without additional components. When the external objects move a small distance, they can be detected by the microlens arrays due to their different focal lengths. It could effectively improve the motion perception of the optical system. Moreover, the focusing and imaging performances of the fabricated artificial compound eye were further tested. The compound eye combines the advantages of monocular eyes and compound eyes, holding great potential for developing advanced optical devices with a large field of view and automatic variable-focus imaging.
Collapse
|
4
|
Xu M, Xue Y, Li J, Zhang L, Lu H, Wang Z. Large-Area and Rapid Fabrication of a Microlens Array on a Flexible Substrate for an Integral Imaging 3D Display. ACS APPLIED MATERIALS & INTERFACES 2023; 15:10219-10227. [PMID: 36753424 DOI: 10.1021/acsami.2c20519] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
A curved integral imaging three-dimensional (3D) display attracts a lot of interest due to its enhanced 3D sense of immersion and wider viewing angle. In this paper, a microlens array (MLA) based on a flexible poly(ethylene terephthalate) (PET) substrate was achieved by a straightforward, rapid, and low-cost technique. The reactive ion etching (RIE) process treated PET/CYTOP covered with a flexible mask to generate a hydrophilic-hydrophobic patterned surface. The well-designed arrays of confined adhesive droplets with a controlled geometry on a hydrophilic-hydrophobic patterned surface were formed using the blade-coating method. A flexible MLA with a diameter of 820 μm, a size of 5.3 cm × 5.1 cm, and a radius of curvature of 25 cm was fabricated and combined with a curved two-dimensional (2D) monitor to realize a lateral viewing range of 6.4 cm at a viewing distance of 25 cm, which is 4 times larger than with flat integral imaging 3D display system. The flexible MLA has the advantages of a controllable lens profile and large pitch, and it can be manufactured on a large scale. In addition, it provides a large viewing angle for the reconstructed 3D image.
Collapse
Affiliation(s)
- Miao Xu
- Academy of Opto-Electric Technology, Special Display and Imaging Technology, Innovation Center of Anhui Province, National Engineering Laboratory of Special Display Technology, Anhui Province Key Laboratory of Measuring Theory and Precision Instrument, School of Instrument Science and Optoelectronics Engineering, Hefei University of Technology, Hefei 230009, China
| | - Yingying Xue
- Academy of Opto-Electric Technology, Special Display and Imaging Technology, Innovation Center of Anhui Province, National Engineering Laboratory of Special Display Technology, Anhui Province Key Laboratory of Measuring Theory and Precision Instrument, School of Instrument Science and Optoelectronics Engineering, Hefei University of Technology, Hefei 230009, China
| | - Jing Li
- Academy of Opto-Electric Technology, Special Display and Imaging Technology, Innovation Center of Anhui Province, National Engineering Laboratory of Special Display Technology, Anhui Province Key Laboratory of Measuring Theory and Precision Instrument, School of Instrument Science and Optoelectronics Engineering, Hefei University of Technology, Hefei 230009, China
| | - Lyudi Zhang
- Academy of Opto-Electric Technology, Special Display and Imaging Technology, Innovation Center of Anhui Province, National Engineering Laboratory of Special Display Technology, Anhui Province Key Laboratory of Measuring Theory and Precision Instrument, School of Instrument Science and Optoelectronics Engineering, Hefei University of Technology, Hefei 230009, China
| | - Hongbo Lu
- Academy of Opto-Electric Technology, Special Display and Imaging Technology, Innovation Center of Anhui Province, National Engineering Laboratory of Special Display Technology, Anhui Province Key Laboratory of Measuring Theory and Precision Instrument, School of Instrument Science and Optoelectronics Engineering, Hefei University of Technology, Hefei 230009, China
| | - Zi Wang
- Academy of Opto-Electric Technology, Special Display and Imaging Technology, Innovation Center of Anhui Province, National Engineering Laboratory of Special Display Technology, Anhui Province Key Laboratory of Measuring Theory and Precision Instrument, School of Instrument Science and Optoelectronics Engineering, Hefei University of Technology, Hefei 230009, China
| |
Collapse
|
5
|
Luan S, Xu P, Zhang Y, Xue L, Song Y, Gui C. Flexible Superhydrophobic Microlens Arrays for Humid Outdoor Environment Applications. ACS APPLIED MATERIALS & INTERFACES 2022; 14:53433-53441. [PMID: 36394606 PMCID: PMC9716522 DOI: 10.1021/acsami.2c17128] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Accepted: 11/07/2022] [Indexed: 06/16/2023]
Abstract
A microlens array (MLA) is an essential optical imaging device in the applications of augmented and virtual realities. The imaging of MLA would become blurry in a humid outdoor atmosphere. While the incorporation of superhydrophobicity to MLA would prevent the adhesion of droplets, the complex structure and the multiple fabrication process reduce the capability of optical imaging of MLA. Herein, a flexible superhydrophobic MLA with good optical imaging capability is successfully fabricated by the combination of 3D direct laser writing (DLW) and soft lithography. 3D DLW allows the fabrication of MLA with a hierarchical pillar array (h-MLA) in one step, which ensures good optical properties of the resulting polydimethylsiloxane (PDMS) h-MLA. The resulting h-MLAs with pitches ranging between 50 and 100 μm are superhydrophobic from which water droplets slide away at a sliding angle smaller than 15.6° and bounce off from the surface. Meanwhile, the hierarchical pillar array has a limited impact on the imaging capability and the field of view of h-MLA. With an optimized pitch of 60 μm, h-MLA has a transparency as good as MLA. Moreover, PDMS h-MLA retains excellent optical and superhydrophobic properties when bent and in an extremely humid environment. We believe that the proposed h-MLA could find applications in outdoor environments.
Collapse
Affiliation(s)
- Shiyi Luan
- School
of Power and Mechanical Engineering, Wuhan
University, Wuhan430072, China
| | - Peng Xu
- School
of Power and Mechanical Engineering, Wuhan
University, Wuhan430072, China
| | - Yurong Zhang
- The
Institute of Technological Sciences, Wuhan
University, Wuhan430072, China
| | - Longjian Xue
- School
of Power and Mechanical Engineering, Wuhan
University, Wuhan430072, China
- The
Institute of Technological Sciences, Wuhan
University, Wuhan430072, China
| | - Yi Song
- The
Institute of Technological Sciences, Wuhan
University, Wuhan430072, China
- School
of Microelectronic, Wuhan University, Wuhan430072, China
| | - Chengqun Gui
- The
Institute of Technological Sciences, Wuhan
University, Wuhan430072, China
| |
Collapse
|
6
|
Double-layer polarization-independent achromatic metasurface array for optical fiber bundle coupling in microendoscope. Sci Rep 2022; 12:20476. [PMID: 36443340 PMCID: PMC9705277 DOI: 10.1038/s41598-022-24785-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Accepted: 11/21/2022] [Indexed: 11/29/2022] Open
Abstract
Optical fiber bundle-based microendoscope, which is significant in clinical diagnosis and industrial detection, calls for miniaturization of the probe and high-resolution observation. Here, we propose a double-layer metasurface array borrowing the structures of insect compound eyes to meet both requirements instead of traditional optical components. Each unit in the array aims for an incident field of view, focusing light at the center of the fiber end face with no chromatic aberration at the wavelengths of 470 nm, 530 nm and 630 nm. The metasurface array is composed of a series of isotropic TiO2 nanopillars which are special selected after considering resonance mode and angular dispersion characteristics, etched on both sides of a silica substrate, with the individual functions of deflecting and focusing. In image space, numerical aperture (NA) is 0.287 and the particular layout of two layers achieve zero telecentricity theoretically, which meet the requirements of optical fiber bundle coupling. A unit for incident angle of 20° is shown to validate our design approach numerically, which obtains a focused spot close to the diffraction limit. The compact and ultrathin metasurface could greatly reduce the size of the probe in optical fiber bundle based microendoscope while ensuring the imaging quality.
Collapse
|
7
|
Luan S, Cao H, Deng H, Zheng G, Song Y, Gui C. Artificial Hyper Compound Eyes Enable Variable-Focus Imaging on both Curved and Flat Surfaces. ACS APPLIED MATERIALS & INTERFACES 2022; 14:46112-46121. [PMID: 36174005 DOI: 10.1021/acsami.2c15489] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
The artificial compound eye (ACE) with zoom imaging requires complex power sources. Meanwhile, its curved substrate makes it difficult for the ACE to realize the zoom imaging on flat surfaces. To realize a wide field of view and a zoom function on both curved and flat surfaces simultaneously, a novel ACE is proposed, which is a bionic design inspired by an ancient creature, trilobite. Compared with a dragonfly, photosensitive units of a trilobite's compound eye are composed of ommatidia with different focal lengths. By learning from this concept, an artificial hyper compound eye (AHCE) was fabricated. Its basic components are five microlenses with different curvatures, and they are capable of being treated as five ommatidia with different focal lengths. Five ommatidia form a photosensitive unit to realize a zoom function. AHCE is capable of variable-focus imaging on curved surfaces. With the information share function, we found that the AHCE not only images on curved surfaces but also has a zoom-imaging function on flat surfaces. The results confirm that the AHCE demonstrates an advanced imaging capability, a variable-focus imaging function on both curved and flat surfaces, which may open new opportunities in developing advanced micro-optical devices.
Collapse
Affiliation(s)
- Shiyi Luan
- School of Power and Mechanical Engineering, Wuhan University, Wuhan430072, China
| | - Hao Cao
- The Institute of Technological Sciences, Wuhan University, Wuhan430072, China
| | - Hongfeng Deng
- The Institute of Technological Sciences, Wuhan University, Wuhan430072, China
| | - Guoxing Zheng
- Electronic Information School, Wuhan University, Wuhan430072, China
| | - Yi Song
- The Institute of Technological Sciences, Wuhan University, Wuhan430072, China
| | - Chengqun Gui
- The Institute of Technological Sciences, Wuhan University, Wuhan430072, China
| |
Collapse
|
8
|
Choi IS, Park S, Jeon S, Kwon YW, Park R, Taylor RA, Kyhm K, Hong SW. Strain-tunable optical microlens arrays with deformable wrinkles for spatially coordinated image projection on a security substrate. MICROSYSTEMS & NANOENGINEERING 2022; 8:98. [PMID: 36119375 PMCID: PMC9474807 DOI: 10.1038/s41378-022-00399-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Revised: 03/03/2022] [Accepted: 05/02/2022] [Indexed: 06/15/2023]
Abstract
As a new concept in materials design, a variety of strategies have been developed to fabricate optical microlens arrays (MLAs) that enable the miniaturization of optical systems on the micro/nanoscale to improve their characteristic performance with unique optical functionality. In this paper, we introduce a cost-effective and facile fabrication process on a large scale up to ~15 inches via sequential lithographic methods to produce thin and deformable hexagonally arranged MLAs consisting of polydimethylsiloxane (PDMS). Simple employment of oxygen plasma treatment on the prestrained MLAs effectively harnessed the spontaneous formation of highly uniform nanowrinkled structures all over the surface of the elastomeric microlenses. With strain-controlled tunability, unexpected optical diffraction patterns were characterized by the interference combination effect of the microlens and deformable nanowrinkles. Consequently, the hierarchically structured MLAs presented here have the potential to produce desirable spatial arrangements, which may provide easily accessible opportunities to realize microlens-based technology by tunable focal lengths for more advanced micro-optical devices and imaging projection elements on unconventional security substrates.
Collapse
Affiliation(s)
- In Sik Choi
- Department of Cogno-Mechatronics Engineering, Department of Optics and Mechatronics Engineering, Pusan National University, Busan, 46241 Republic of Korea
| | - Seongho Park
- Research Center for Dielectric and Advanced Matter Physics, Pusan National University, Busan, 46241 Republic of Korea
- Department of Physics, University of Oxford, Oxford, OX1 3PU UK
| | - Sangheon Jeon
- Department of Cogno-Mechatronics Engineering, Department of Optics and Mechatronics Engineering, Pusan National University, Busan, 46241 Republic of Korea
| | - Young Woo Kwon
- Department of Nano-Fusion Technology, Pusan National University, Busan, 46241 Republic of Korea
| | - Rowoon Park
- Department of Cogno-Mechatronics Engineering, Department of Optics and Mechatronics Engineering, Pusan National University, Busan, 46241 Republic of Korea
| | | | - Kwangseuk Kyhm
- Department of Cogno-Mechatronics Engineering, Department of Optics and Mechatronics Engineering, Pusan National University, Busan, 46241 Republic of Korea
| | - Suck Won Hong
- Department of Cogno-Mechatronics Engineering, Department of Optics and Mechatronics Engineering, Pusan National University, Busan, 46241 Republic of Korea
| |
Collapse
|
9
|
Yang T, Li M, Yang Q, Lu Y, Cheng Y, Zhang C, Du B, Hou X, Chen F. Femtosecond Laser Fabrication of Submillimeter Microlens Arrays with Tunable Numerical Apertures. MICROMACHINES 2022; 13:mi13081297. [PMID: 36014220 PMCID: PMC9414556 DOI: 10.3390/mi13081297] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Revised: 07/17/2022] [Accepted: 08/04/2022] [Indexed: 06/12/2023]
Abstract
In recent years, the demand for optical components such as microlenses has been increasing, and various methods have been developed. However, fabrication of submillimeter microlenses with tunable numerical aperture (NA) on hard and brittle materials remains a great challenge using the current methods. In this work, we fabricated a variable NA microlens array with submillimeter size on a silica substrate, using a femtosecond laser-based linear scanning-assisted wet etching method. At the same time, the influence of various processing parameters on the microlens morphology and NA was studied. The NA of the microlenses could be flexibly adjusted in the range of 0.2 to 0.45 by changing the scanning distance of the laser and assisted wet etching. In addition, the imaging and focusing performance tests demonstrated the good optical performance and controllability of the fabricated microlenses. Finally, the optical performance simulation of the prepared microlens array was carried out. The result was consistent with the actual situation, indicating the potential of the submillimeter-scale microlens array prepared by this method for applications in imaging and detection.
Collapse
Affiliation(s)
- Tongzhen Yang
- School of Mechanical Engineering, Xi’an Jiaotong University, Xi’an 710049, China
| | - Minjing Li
- School of Mechanical Engineering, Xi’an Jiaotong University, Xi’an 710049, China
| | - Qing Yang
- School of Mechanical Engineering, Xi’an Jiaotong University, Xi’an 710049, China
| | - Yu Lu
- State Key Laboratory for Manufacturing System Engineering and Shaanxi Key Laboratory of Photonics Technology for Information, School of Electronic Science and Engineering, Xi’an Jiaotong University, Xi’an 710049, China
| | - Yang Cheng
- School of Mechanical Engineering, Xi’an Jiaotong University, Xi’an 710049, China
| | - Chengjun Zhang
- School of Mechanical Engineering, Xi’an Jiaotong University, Xi’an 710049, China
| | - Bing Du
- State Key Laboratory for Manufacturing System Engineering and Shaanxi Key Laboratory of Photonics Technology for Information, School of Electronic Science and Engineering, Xi’an Jiaotong University, Xi’an 710049, China
| | - Xun Hou
- State Key Laboratory for Manufacturing System Engineering and Shaanxi Key Laboratory of Photonics Technology for Information, School of Electronic Science and Engineering, Xi’an Jiaotong University, Xi’an 710049, China
| | - Feng Chen
- State Key Laboratory for Manufacturing System Engineering and Shaanxi Key Laboratory of Photonics Technology for Information, School of Electronic Science and Engineering, Xi’an Jiaotong University, Xi’an 710049, China
| |
Collapse
|
10
|
Han S, Sung J, Ko B, Kwon M, Kim S, So H. A biomimetic compound eye lens for photocurrent enhancement at low temperatures. BIOINSPIRATION & BIOMIMETICS 2022; 17:046008. [PMID: 35504271 DOI: 10.1088/1748-3190/ac6c65] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Accepted: 05/03/2022] [Indexed: 06/14/2023]
Abstract
In this study, an artificial compound eye lens (ACEL) was fabricated using a laser cutting machine and polyvinyl alcohol (PVA) solution. A laser cutter was used to punch micro-sized holes (500 μm diameter-the smallest possible diameter) into an acrylic plate; this punched plate was then placed on the aqueous PVA solution, and the water was evaporated. The plate was used as the mold to obtain a polydimethylsiloxane (PDMS) micro lens array film, which was fixed to a dome-shaped three-dimensional-printed mold for further PDMS curing, and a hemispherical compound eye lens was obtained. Using a gallium nitride (GaN) photodetector, a light detection experiment was performed with the ACEL, bare lens, and no lens by irradiating light at various angles under low temperatures. The photodetector with the ACEL generated a high photocurrent under several conditions. In particular, when the light was irradiated at 0° and below -20 °C, the photocurrent of the GaN sensor with the ACEL increased by 61% and 81% compared with the photocurrent of the GaN sensor with the bare lens and without a lens, respectively. In this study, a sensor for detecting light with ACEL was demonstrated in low-temperature environments, such as indoor refrigerated storages and external conditions in Antarctica and Arctic.
Collapse
Affiliation(s)
- Sanghu Han
- Department of Mechanical Engineering, Hanyang University, Seoul 04763, Republic of Korea
| | - Jaebum Sung
- Department of Mechanical Engineering, Hanyang University, Seoul 04763, Republic of Korea
| | - Byeongjo Ko
- Department of Mechanical Engineering, Hanyang University, Seoul 04763, Republic of Korea
| | - Minjun Kwon
- Korea Institute of Industrial Technology, Cheonan 31056, Republic of Korea
| | - Sewon Kim
- Korea Institute of Industrial Technology, Cheonan 31056, Republic of Korea
| | - Hongyun So
- Department of Mechanical Engineering, Hanyang University, Seoul 04763, Republic of Korea
- Institute of Nano Science and Technology, Hanyang University, Seoul 04763, Republic of Korea
| |
Collapse
|
11
|
Wu X, Fang C, Xu W, Zhang D. Bioinspired Compound Eyes for Diffused Light-Harvesting Application. ACS APPLIED MATERIALS & INTERFACES 2022; 14:4767-4774. [PMID: 35014247 DOI: 10.1021/acsami.1c22501] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Natural compound eyes endow arthropods with wide-field high-performance light-harvesting capability that enables them to capture prey and avoid natural enemies in dim light. Inspired by natural compound eyes, a curved artificial-compound-eye (cACE) photodetector for diffused light harvesting is proposed and fabricated, and its light-harvesting capability is systematically investigated. The cACE photodetector is fabricated by introducing a cACE as a light-harvesting layer on the surface of a silicon-based photodetector, with the cACE being prepared via planar artificial-compound-eye (pACE) template deformation. The distinctive geometric morphology of the as-prepared cACE effectively reduces its surface reflection and the dependence of the projected area on the incident light direction, thereby significantly improving the light-harvesting ability and output photocurrent of the silicon-based photodetector. Furthermore, the performances of cACE, pACE, and bare polydimethylsiloxane (PDMS)-attached photodetectors as diffused light detectors are investigated under different luminances. The cACE-photodetector output photocurrent is 1.395 and 1.29 times those of the bare PDMS-attached and pACE photodetectors, respectively. Moreover, this photodetector has a desirable geometric shape. Thus, the proposed cACE photodetector will facilitate development of high-performance photodetectors for luminance sensing.
Collapse
Affiliation(s)
- Xinxue Wu
- Wenzhou Key Laboratory of Micro-nano Optoelectronic Devices, College of Electrical and Electronic Engineering, Wenzhou University, Wenzhou, Zhejiang 325035, China
| | - Chaolong Fang
- Wenzhou Key Laboratory of Micro-nano Optoelectronic Devices, College of Electrical and Electronic Engineering, Wenzhou University, Wenzhou, Zhejiang 325035, China
| | - Wangdong Xu
- Wenzhou Key Laboratory of Micro-nano Optoelectronic Devices, College of Electrical and Electronic Engineering, Wenzhou University, Wenzhou, Zhejiang 325035, China
| | - Dawei Zhang
- Engineering Research Center of Optical Instrument and System, the Ministry of Education, Shanghai Key Laboratory of Modern Optical System, University of Shanghai for Science and Technology, Shanghai 200093, China
| |
Collapse
|
12
|
Su S, Liang J, Li X, Xin W, Ye X, Xiao J, Xu J, Chen L, Yin P. Hierarchical Artificial Compound Eyes with Wide Field-of-View and Antireflection Properties Prepared by Nanotip-Focused Electrohydrodynamic Jet Printing. ACS APPLIED MATERIALS & INTERFACES 2021; 13:60625-60635. [PMID: 34886666 DOI: 10.1021/acsami.1c17436] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Artificial compound eyes (ACEs) endowed with durable superhydrophobicity, wide field-of-view (FOV), and antireflection properties are extremely appealing in advanced micro-optical systems. However, the simple and high-efficiency fabrication of ACEs with these functions is still a major challenge. Herein, inspired by moth eyes, ACEs with hierarchical macro/micro/nano structures were fabricated using the combination of nanotip-focused electrohydrodynamic jet (NFEJ) printing and air-assisted deformation processes. The NFEJ printing enables the direct and maskless fabrication of hierarchical micro/nanolens arrays (M/NLAs) without intermediate steps. The introduction of M/NLAs on the eye surface significantly improves the water hydrophobic performance with a water contact angle of 161.1° and contact angle hysteresis (CAH) of 4.2° and generally decreases the reflectance by 51% in the wavelength range of 350-1600 nm in comparison to the macroeye without any structures. The contact angle remains almost unchanged, and the CAH slightly increases from 4.2° to 8.7° after water jet impact for 20 min, indicating a durable superhydrophobicity. Moreover, the results confirm that the durable superhydrophobic ACEs with antireflection properties exhibit excellent imaging quality and a large FOV of up to 160° without distortion.
Collapse
Affiliation(s)
- Shijie Su
- Key Laboratory for Micro/Nano Technology and System of Liaoning Province, Dalian University of Technology, Dalian 116024, China
| | - Junsheng Liang
- Key Laboratory for Micro/Nano Technology and System of Liaoning Province, Dalian University of Technology, Dalian 116024, China
- Key Laboratory for Precision and Non-traditional Machining Technology of Ministry of Education, Dalian University of Technology, Dalian 116024, China
| | - Xiaojian Li
- Key Laboratory for Precision and Non-traditional Machining Technology of Ministry of Education, Dalian University of Technology, Dalian 116024, China
| | - Wenwen Xin
- Key Laboratory for Micro/Nano Technology and System of Liaoning Province, Dalian University of Technology, Dalian 116024, China
| | - Xushi Ye
- Key Laboratory for Precision and Non-traditional Machining Technology of Ministry of Education, Dalian University of Technology, Dalian 116024, China
| | - Jianping Xiao
- Key Laboratory for Micro/Nano Technology and System of Liaoning Province, Dalian University of Technology, Dalian 116024, China
| | - Jun Xu
- Key Laboratory of Materials Modification by Laser, Ion and Electron Beams, Ministry of Education, Dalian University of Technology, Dalian 116024, China
| | - Li Chen
- Key Laboratory for Precision and Non-traditional Machining Technology of Ministry of Education, Dalian University of Technology, Dalian 116024, China
| | - Penghe Yin
- Key Laboratory for Precision and Non-traditional Machining Technology of Ministry of Education, Dalian University of Technology, Dalian 116024, China
| |
Collapse
|
13
|
Yuan Y, Xu M, Wang X, Lu H, Qiu L. Polyvinyl alcohol microlens array obtained by solvent evaporation from a confined droplet array. APPLIED OPTICS 2021; 60:10914-10919. [PMID: 35200853 DOI: 10.1364/ao.442508] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Accepted: 11/02/2021] [Indexed: 06/14/2023]
Abstract
In this study, polyvinyl alcohol (PVA) microlens arrays (MLAs) were prepared, and the dynamics of contact lines and contact angles during confined PVA solution droplet evaporation were investigated by in situ optical microscopy. First, hydrophobic layers patterned with hydrophilic microholes array modified substrates were prepared by photolithography and coating methods. The flowing of PVA solution on the substrates formed droplets in each microhole self-assembly. The substrate was then heated to allow evaporation of the solvent. The results showed the contact line of confined droplets pinned at the junction between the hydrophilic and hydrophobic areas during the whole evaporation process. The apparent contact angle decreased nonlinearly during evaporation. The evaporation of PVA solution droplet in each microhole followed a constant contact radius mode, meaning constant contact area and declined contact angle during evaporation. After complete solvent evaporation, PVA formed a convex shape with convergent lens character in each microhole. In sum, the obtained PVA convex arrays with uniform sizes and good focusing properties would have potential applications in wavefront sensing, infrared focal plane detection or CCD array light accumulation, laser array scanning, laser display, optical fiber coupling, and many other optical systems.
Collapse
|
14
|
Zheng Y, Wang D, Jiang Z, Liu C, Wang QH. Continuous zoom compound eye imaging system based on liquid lenses. OPTICS EXPRESS 2021; 29:37565-37579. [PMID: 34808826 DOI: 10.1364/oe.444188] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Accepted: 10/19/2021] [Indexed: 06/13/2023]
Abstract
In this paper, a continuous zoom compound eye imaging system based on liquid lenses is proposed. The main imaging part of the system consists of a liquid compound eye, two liquid lenses and a planar image sensor. By adjusting the liquid injection volumes of the liquid compound eye and liquid lenses, the system can realize continuous zoom imaging without any mechanical movement of imaging components. According to the results of experiments, the paraxial magnification of the target can range from ∼0.019× to ∼0.037× at a fixed working distance. Moreover, the system can realize continuous focusing at a fixed paraxial magnification when the working distance ranges from ∼200mm to ∼300mm. Compared with the traditional artificial compound eye imaging systems, the proposed system increases the adjustability and matches the variable image surfaces of the liquid compound eye to a planar image sensor. The aspherical effects of the liquid compound eye and liquid lenses are also considered in the design of the system. The system is expected to be used for imaging in various scenes, such as continuous zoom panoramic imaging, 3D scanning measurement and so on.
Collapse
|
15
|
Zhang Y, Chen X, Wang MY, Yu H. Multidimensional Tactile Sensor with a Thin Compound Eye-Inspired Imaging System. Soft Robot 2021; 9:861-870. [PMID: 34619070 DOI: 10.1089/soro.2020.0202] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Artificial tactile sensing for robots is a counterpart to the human sense of touch, serving as a feedback interface for sensing and interacting with the environment. A vision-based tactile sensor has emerged as a novel and advantageous branch of artificial tactile sensors. Compared with conventional tactile sensors, vision-based tactile sensors possess stronger potential thanks to acquiring multimodal contact information in much higher spatial resolution, although they typically suffer from bulky size and fabrication challenges. In this article, we report a thin vision-based tactile sensor that draws inspiration from natural compound eye structures and demonstrate its capability of sensing three-dimensional (3D) force. The sensor is composed of an array of vision units, an elastic touching interface, and a supporting structure with illumination. Experiments validated the sensor's advantages, including competitive spatial resolution of deformation as high as 1016 dpi on a 5 × 8 mm2 sensing area, superior accuracy of 3D force measurement at levels of 0.018 N for tangential force and 0.213 N (0.108 N at the center region) for normal force, and real-time processing at 30 Hz, while achieving a thin size of 5 mm. We further demonstrate the sensor capability in sensing 3D force and slip occurrence in real grasping experiments. This device paves the way for robotic applications that require rich tactile information with miniaturized sensor structure.
Collapse
Affiliation(s)
- Yazhan Zhang
- Department of Mechanical and Aerospace Engineering and Hong Kong University of Science and Technology, Hong Kong, Hong Kong
| | - Xia Chen
- Department of Mechanical and Aerospace Engineering and Hong Kong University of Science and Technology, Hong Kong, Hong Kong
| | - Michael Yu Wang
- Department of Mechanical and Aerospace Engineering and Hong Kong University of Science and Technology, Hong Kong, Hong Kong.,Department of Electronic and Computer Engineering, Hong Kong University of Science and Technology, Hong Kong, Hong Kong
| | - Hongyu Yu
- Department of Mechanical and Aerospace Engineering and Hong Kong University of Science and Technology, Hong Kong, Hong Kong
| |
Collapse
|
16
|
Li J, Wang W, Zhu R, Huang Y. Superhydrophobic Artificial Compound Eye with High Transparency. ACS APPLIED MATERIALS & INTERFACES 2021; 13:35026-35037. [PMID: 34255480 DOI: 10.1021/acsami.1c05558] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Natural compound eyes have inspired the development of self-cleaning, waterproof, and antifog optical devices. However, the traditional methods generally sacrifice the transparency of optical units to introduce hydrophobicity, which significantly limits the practical applications of state-of-the-art hydrophobic technologies. This work aims to fabricate a microimaging system by combining photolithography, inkjet printing, and chemical growth. Herein, an artificial compound eye (ACE) is endowed with stable superhydrophobicity and high transparency without affecting its optical performance. The obtained ACE system possesses good static and dynamic dewetting properties along with excellent optical performance. Its static contact angle exceeds 160°, whereas the sliding angle and contact angle hysteresis values are ∼5.5° and ∼3.8°, respectively. Furthermore, the contact time is found to be 11.97 s for the Weber number of 12. The droplet undergoes a reversible process during compressing and stretching, and the ACE exhibits no adhesion under a pressure load of 4 mN. This proves that the introduction of nonwetting nanohairs on the sidewalls of the microcone arrays significantly improves the dynamic dewetting of the system. More importantly, the properly designed position of nanohairs ensures that the optical performance of ACE is maintained at a level of ∼95% compared to that of the bare glass. The superhydrophobic ACE exhibits low adhesion and great transparency. This rationally designed ACE may provide useful guidelines for fabrication of superhydrophobic optical devices with high transparency and enable potential applications in military, medical, and some outdoor activity fields.
Collapse
Affiliation(s)
- Jiang Li
- College of Mechanical and Electronic Engineering, Northwest A&F University, Yangling 712100, China
| | - Wenjun Wang
- State Key Laboratory for Manufacturing Systems Engineering, Xi'an Jiaotong University, Xi'an 710054, China
| | - Ruixiang Zhu
- College of Mechanical and Electronic Engineering, Northwest A&F University, Yangling 712100, China
| | - Yuxiang Huang
- College of Mechanical and Electronic Engineering, Northwest A&F University, Yangling 712100, China
| |
Collapse
|
17
|
Artificial Compound Eye Systems and Their Application: A Review. MICROMACHINES 2021; 12:mi12070847. [PMID: 34357257 PMCID: PMC8307767 DOI: 10.3390/mi12070847] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Revised: 07/08/2021] [Accepted: 07/15/2021] [Indexed: 12/24/2022]
Abstract
The natural compound eye system has many outstanding properties, such as a more compact size, wider-angle view, better capacity to detect moving objects, and higher sensitivity to light intensity, compared to that of a single-aperture vision system. Thanks to the development of micro- and nano-fabrication techniques, many artificial compound eye imaging systems have been studied and fabricated to inherit fascinating optical features of the natural compound eye. This paper provides a review of artificial compound eye imaging systems. This review begins by introducing the principle of the natural compound eye, and then, the analysis of two types of artificial compound eye systems. We equally present the applications of the artificial compound eye imaging systems. Finally, we suggest our outlooks about the artificial compound eye imaging system.
Collapse
|
18
|
Wang W, Yang W, Mei X, Li J, Sun X. Fabrication of self-aligning convergent waveguides of microlens arrays to collect and guide light. OPTICS EXPRESS 2021; 29:3327-3341. [PMID: 33770933 DOI: 10.1364/oe.413243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Accepted: 01/04/2021] [Indexed: 06/12/2023]
Abstract
The optical properties of microlens arrays may be significantly affected by the optical crosstalk effect between adjacent lenses. Recently, this issue has triggered increasing attention in the scientific community. In this study, an integrated microlens array (MLA) consisting of self-aligning convergent waveguides of microlenses was fabricated. The optical crosstalk effect does not influence the performance of such system. Based on the self-focusing effect principle, self-writing of the waveguide array was achieved in a photosensitive polymer. The light collection and guiding performance of the MLA with and without thermal cross-linking treatment was analyzed in depth. The relation between the stray light and the filling rate of the MLA shows that a high filling rate decreases the optical crosstalk. Finally, an integrated MLA with a large area, high uniformity, and excellent optical performance was fabricated.
Collapse
|
19
|
Li Z, Xu M, Lu H, Ding Y. A polyvinyl alcohol microlens array with controlled curvature on discontinuous hydrophobic surface. J Mol Liq 2020. [DOI: 10.1016/j.molliq.2020.114372] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
|
20
|
Li J, Wang W, Mei X, Pan A. Designable Ultratransparent and Superhydrophobic Surface of Embedded Artificial Compound Eye with Extremely Low Adhesion. ACS APPLIED MATERIALS & INTERFACES 2020; 12:53557-53567. [PMID: 33176099 DOI: 10.1021/acsami.0c18881] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Real-world implementation of artificial compound eye (ACE) has been limited by its poor transparency and high requirement for the stable Cassie state. In general, the improvement of surface dewetting performance sacrifices the transparency of ACE. Herein, ACE was obtained by an integrated manufacturing technology that combined photolithography, microprinting, and chemical growth. Through skillful manipulation of the fabrication process, dewetting hairs were fabricated on the top of micropillars and around the microlens. The combination of nanohairs and micropillars resulted in outstanding superhydrophobicity (∼170°), pristine lotus effect with low sliding angle (∼1°), and contact angle hysteresis (∼2°). Moreover, the surface showed almost no adhesion under a preload of 4 mN, exhibiting excellent stable Cassie state and antiadhesion performance. Furthermore, dynamic impact showed that the impacting droplet was quickly detached from the surface (contact time ∼14.1 ms) without sticking for We = 60. The designed transparency resulted in high performance of optical unit (∼99%, bare glass for comparison). Moreover, ACE exhibited better focusing and imaging capability under larger aperture diameter than microlens without nanohairs. We envision that this research presents a significant advancement in imparting superhydrophobicity and transparency to a so-far inapplicable family of optical devices for many practical outdoor applications.
Collapse
Affiliation(s)
- Jiang Li
- State Key Laboratory for Manufacturing System Engineering, Xi'an Jiaotong University, Xian 710054, China
- Shaanxi Key Laboratory of Intelligent Robots, Xi'an Jiaotong University, Xian 710049, China
| | - Wenjun Wang
- State Key Laboratory for Manufacturing System Engineering, Xi'an Jiaotong University, Xian 710054, China
- Shaanxi Key Laboratory of Intelligent Robots, Xi'an Jiaotong University, Xian 710049, China
| | - Xuesong Mei
- State Key Laboratory for Manufacturing System Engineering, Xi'an Jiaotong University, Xian 710054, China
- Shaanxi Key Laboratory of Intelligent Robots, Xi'an Jiaotong University, Xian 710049, China
| | - Aifei Pan
- State Key Laboratory for Manufacturing System Engineering, Xi'an Jiaotong University, Xian 710054, China
- Shaanxi Key Laboratory of Intelligent Robots, Xi'an Jiaotong University, Xian 710049, China
| |
Collapse
|
21
|
Fabrication and Characterization of Curved Compound Eyes Based on Multifocal Microlenses. MICROMACHINES 2020; 11:mi11090854. [PMID: 32947769 PMCID: PMC7569987 DOI: 10.3390/mi11090854] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/15/2020] [Revised: 09/09/2020] [Accepted: 09/14/2020] [Indexed: 12/12/2022]
Abstract
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.
Collapse
|