Apposition compound eyes consist of independent ommatidium imaging channels, which are composed of refractive devices (such as cornea and crystal cone) and a rhabdom. As light enters the refractive device, it is focused onto the rhabdom through the refractive apparatus. The rhabdom then transmits the focused light to the optic nerve for further processing and imaging. Additionally, to enhance the quality of imaging, the imaging channels of adjacent ommatidia are separated in all directions by pigment cells, preventing any interference or crosstalk of light (Guo et al., 2021). Based on the actual structure of the biological compound eye, the schematic diagram of the apposition compound eye can be simplified and depicted as shown in Figure 1A. Similarly, an imaging schematic diagram of an artificial apposition compound eye can also be obtained, as shown in Figure 1B, where the focusing lens corresponds to the cornea, the substrate lens corresponds to the crystalline cone, and the detector corresponds to the rhabdom and retinula cells.

Although both the apposition compound eye and the superposition compound eye have a similar structural composition, the imaging principles are significantly different. The photoreceptive cells in superposition compound eyes receive incident light from multiple corneas, whereas the photoreceptive cells in apposition eyes receive incident light solely from the corresponding cornea.

The superposition compound eye can be further categorized into optical superposition compound eyes and neural superposition compound eyes, depending on the different mechanisms of light perception. In optical superposition compound eyes, incident light is focused onto a specific region of photoreceptive cells through optical reflection or refraction. As a result, optical superposition compound eyes exhibit higher sensitivity and smaller focal ratios (F-numbers) compared to apposition compound eyes (Land et al., 1979). Figure 2 illustrates three types of optical compound eyes with superposition, namely, optical refraction superposition, optical reflection superposition, and parabolic superposition, corresponding to optical propagation paths generated by the mechanisms of refraction, reflection, and a combination of both, respectively (Land, 1981; Wagner et al., 2022). Organisms with optical superposition compound eyes inhabit dark environments and possess remarkable light-capturing capabilities and efficient utilization of light energy (Frederiksen and Warrant, 2008; Song et al., 2017). Whereas the neural superposition compound eye receives incident light through the photoreceptive nerve from multiple ommatidia. Therefore, when the number of ommatidium is the same, the neural superposition compound eye has higher resolution.

Prior to the 21st century, manufacturing artificial compound eyes primarily concentrated on flat compound eyes due to the limitations of processing technology during that period (Oikawa et al., 1981; Borrelli et al., 1985; Popovic et al., 1988; Cheng et al., 2019). Various technologies, including stamping, reversal replication, droplet deposition, thermal reflow and lithography, were employed to enhance the precision and efficiency of manufacturing planar compound eyes (Yang et al., 2005; Hong et al., 2006; Chang et al., 2007; Pan and Su, 2008; Yu et al., 2013; Cherng and Su, 2014; Park et al., 2014; Yong et al., 2015; Grigaliunas et al., 2016). Among these technologies, the processing methods for planar compound eyes can be roughly divided into two categories: direct forming technology and indirect forming technology. Unlike direct forming technology, which directly deals with the contour of compound eyes using one or more specialized manufacturing technique, indirect forming technology involves initially producing the mold of the compound eyes and then obtaining the planar compound eye structure through demolding or hot embossing processes.

Although the planar compound eye has significantly enhanced the imaging clarity of optical systems, its planar arrangement restricts its applications in various fields. To address these limitations, a curved structure has been explored as a potential solution. Researchers are now shifting their focus from planar compound eyes to curved compound eyes in order to achieve larger field of view, higher integration, and intelligence (Maddern and Wyeth, 2008; Li and Yi, 2010; Deng et al., 2016; Liang et al., 2019). The advancement of micro-nano processing technology and flexible materials has led to significant progress in improving the resolution, field of view, antifouling ability, and zoom integration of curved compound eyes. This section aims to discuss the curved compound eye under different processing types, including single manufacturing technologies such as femtosecond laser two-photon polymerization, as well as other composite manufacturing methods. The objective is to explore the various advancements and achievements in this field.

In previous research on natural compound eyes and artificial compound eyes, it has been observed that both types have ommatidia with fixed focal lengths, limiting their ability to achieve variable focal length imaging. To address this limitation, Z.C. Ma et al. developed an intelligently tunable compound eye lens. They fabricated a stimuli-responsive compound eye based on bovine serum albumin (BSA) using femtosecond laser two-photon polymerization. The compound eye lens consists of a double-layer structure. The outer layer is created using two-photon polymerization technology to drop BSA aqueous solution gel onto a glass substrate, while the inner layer is made using the same processing method but with SU-8 photoresist solution. Figure 6A illustrates the contraction and expansion of BSA at different pH values, demonstrating that not only can the focal length of the compound eye lens be adjusted, but also the field of view (FOV) can be modified within the range of 35°–80°. Furthermore, Figure 6B presents the imaging quality and imaging distance of the compound eye under different pH values (Ma et al., 2019). These findings showcase the potential of intelligently tunable compound eyes in achieving variable focal length and adjusting the FOV.

Although femtosecond laser two-photon polymerization technology has been used to fabricate 3D high-precision compound eye lenses, the processing efficiency is hindered by the point-to-point processing method. To overcome this challenge, D. Wu et al. proposed a scanning strategy to control the voxel size and introduced a high-speed voxel-modulated femtosecond laser direct writing technology to achieve the three-dimensional structure of artificial compound eyes. This advancement not only enables rapid processing of artificial compound eyes but also realizes a small (84 μm) wide-field imaging system without distortions. The artificial compound eye was fabricated using laser direct writing, as shown in Figures 6C, D. The first step involved scanning the inner macrobase with a 400 nm fs laser, followed by the scanning of small ommatidia on the macrobase using a 100 nm fs laser without any gap. While the small voxel mode allows for highly precise devices, it is limited by prolonged fabrication times, which can make this method impractical. However, an improved laser direct writing strategy has been developed, achieving a large aperture (0.4), a high fill factor (100%), and ultra-low surface roughness. The images of the letters in Figures 6E–G demonstrate that the artificial compound eye exhibits high optical imaging quality and uniformity in all directions (Wu et al., 2014).

Compound processing involves creating a curved compound eye using two or more methods. Mechanical deformation, imprinting, vacuum absorption, and mold rotation are commonly employed techniques. These methods are straightforward and efficient. In the field of zoom imaging for curved compound eyes, L. Li et al. proposed a design for a flexible zoom artificial compound eye Li et al. (2018). The surface compound eye is divided into three fan-shaped regions with different focal lengths, as depicted in Figure 7A. Through aspheric optimization, the spherical aberration of each region is reduced to 1% of the initial value. The design not only allows for focal length adjustment but also addresses the issue of poor imaging quality at the edges of curved compound eyes. The structure of the artificial curved compound eye is formed using mold processing. The mold is created using a precision five-axis CNC machine, and the molding material used is polydimethylsiloxane (PDMS). A mixture of curing agent and PDMS, in a ratio of 1:10, is poured into the mold and cured at a fixed temperature of 80°C for 1 h to obtain the complete structure shown in Figure 7B. The imaging effect of the compound eye and a multi-eye positioning experiment are demonstrated in Figures 7C, D.

The design of the flexible zoom compound eye incorporates a regional zoom approach. However, traditional designs have limited flexibility and can only zoom within a certain range. To address this issue, J. J. Cao et al. developed a tunable bionic compound eye Cao et al. (2020). The structure is created using femtosecond laser wet etching technology. Initially, the silicon wafer template, which underwent laser processing, is etched in a solution containing hydrofluoric acid (HF), nitric acid (HNO₃), and acetic acid (CH₃COOH). Subsequently, the microstructure of the template is transferred onto a PDMS substrate through the demolding process. The resulting PDMS microlens array (MLA) is flexible and deformable, and it is integrated with a microfluidic chamber to enable zoom imaging, as shown in Figure 8A. By adjusting the volume of water injected into the microfluidic chamber, the compound eye can transition from a planar structure to a hemispherical shape, achieving a field of view (FOV) of 180° and a variable focal length ranging from 3.03 mm to infinity. The angular resolution of the compound eye is 3.86 × 10⁻⁴ rad, granting it the capability to detect targets at different distances, as depicted in Figures 8B–G.

Although the tunable bionic compound eye can achieve flexible focal length, it needs to zoom through the solution volume, and the response time is slow, which limits the practical application of the compound eye. In response to this problem, S.Y. Luan et al. inspired by the bionic design of ancient trilobites, created an artificial super compound eye (AHCE) Luan et al. (2022). It is a microlens with five different curvatures, which can be regarded as a small eye with five different focal lengths. The surface and plane zoom functions are realized under the composition of five small eyes, as shown in Figures 9A, B. The structure obtains the planar zoom MLA of the required mold by laser direct writing technology and controlling the exposure position and intensity through the optical system. After putting the PDMS-coated zoom MLA into the oven, the soft film of the zoom MLA was obtained by demoulding or soft lithography. The soft film of zoom MLA is bonded to the concave lens to obtain the template of AHCE. Then, the cyclic olefin copolymer (COC) was poured on the PDMS on the concave lens and covered with a glass substrate. Finally, through UV curing and demolding, the artificial super compound eye lens is obtained as shown in Figure 9C. Since AHCE is composed of five small eyes with different focal lengths, the structure can not only perform zoom imaging on the surface, but also form zoom imaging functions on planes with different distances through information sharing and scaling functions, as shown in Figures 9D–J. J. Li et al. also proposed a curved compound eye lens based on inkjet printing and air-assisted deformation for the zoom response of the compound eye Li et al. (2023).

The development of curved zoom compound eye lenses has addressed the zoom problem encountered in artificial compound eyes and has played a significant role in integrating curved compound eye systems. However, the compound eye system often operates in humid or harsh environments, making it susceptible to a decline in imaging quality caused by water mist. Therefore, it is crucial to enhance the lens’s hydrophobicity and self-cleaning ability.

In a study by J. Li et al., a combination of modified laser swelling, air-assisted techniques, and controlled crystal growth was employed to create an artificial compound eye without distortion Li et al. (2019). Initially, a microlens array was fabricated using laser swelling technology on a substrate. The convex array template was then fixed onto 184 elastic slabs. By attaching a concave membrane to a circular chamber connected to a vacuum pump, the membrane was deformed from a plane to a surface. The process is shown in Figure 10A. This process resulted in a bioinspired compound eye with nano structures, as observed in the scanning electron microscope (SEM) image shown in Figures 10B, C. The introduced nano structures effectively reduced surface reflectance and improved surface hydrophobicity. The bioinspired compound eye exhibited a nearly normal incidence distribution along the x and y directions, with a decrease in central light intensity as the angle of incidence increased. It demonstrated excellent imaging properties and focusing ability under tilted incident light.

Another approach using an electro-hydrodynamic jet printing technology for manufacturing waterproof artificial compound eyes was proposed by Zhou et al. (2020). The processing scheme, as illustrated in Figure 10F, involved spraying a microlens array onto a flexible PDMS film and deforming the film using an integrated microfluidics chip to create the artificial compound eye with a variable field of view (FOV). The flexible film, consisting of a hybrid of microlens and nanolens arrays, exhibited superb superhydrophobic properties with a water contact angle of 158°. Experimental tests on the imaging ability were conducted, and Figures 10G–I shows the imaging results of the letters “SIA” captured from the center, middle, and edge regions. The focused lens at the center of the microlens array can be clearly observed, as the film transitions from a planar to a curved surface upon deformation. Figures 10J–L depicts the deformation state of the microlens array film for the artificial compound eyes, and Figures 10M–O illustrates the intensity distribution of the circled positions. The microfluidics chip enabled the creation of artificial compound eyes with a variable FOV ranging from 0° to 160°.

Although the above two kinds of compound eyes can achieve hydrophobicity, the superhydrophobic surface is obtained at the expense of the transparency of the compound eye, and the micro-nano manufacturing process used is not conducive to large-scale production. At the same time, when subjected to high pressure, long-term work or wear, these superwetting surfaces have poor stability, which can lead to the loss of hydrophobicity. In response to this problem, M.J. Li et al. inspired by the Nepenthes capture, designed an anti-fog and anti-fouling compound eye structure Li et al. (2022). The structure uses femtosecond laser wet etching method to, etch the required microstructure template on the curved K9 optical glass, apply PDMS to the template, and obtain the required ACE after cooling and demoulding. The structure uses femtosecond laser wet etching method to, etch the required microstructure template on the curved K9 optical glass, apply PDMS to the template, and obtain the required ACE after cooling and demoulding. ACE was immersed in silicone oil for several hours to form a smooth surface injected with lubricant. The processing flow is shown in Figure 11A. The compound eye structure integrates more than 3,000 microlenses, which not only achieves 64°FOV, but also has a spatial resolution of 50.8 lp mm^–1. It can withstand continuous water mist exposure of 1.45 mL min^–1 at least 144s as shown in Figure 11B. The structure has high self-cleaning performance and can repel complex liquids as shown in Figure 11C. It has great potential in autonomous driving, medical or visual systems in harsh environments.

The compound visual organs mentioned earlier are fabricated mainly from synthetic polymers. But regretfully, this restricts their potential applicability due to their susceptibility to distortion when exposed to elevated temperatures and intense pressures. Conversely, artificial compound eyes constructed from glass present a promising prospect for expansive imaging and swift detection, owing to their extraordinary thermal and mechanical resiliency.

To address this challenge, X.Q. Liu et al. proposed a technology that utilizes sapphire concave compound eyes as high-temperature and hard-casting templates Liu et al. (2019a). A dry etching assisted femtosecond laser processing method was used to create centimeter-sized concave compound eyes on a curved sapphire substrate. The process involved carving microholes on the curved sapphire substrate through femtosecond laser scanning, followed by dry etching to form the concave compound eyes. By employing a femtosecond laser manufacturing system, they rapidly fabricated a uniform concave compound eye with a diameter of 20 μm and a depth of 1.5 μm. Subsequently, a glass compound eye was created using a high-temperature casting method, as illustrated in Figure 12A. The resulting compound eye produced clear images of the letter “F” from the center, middle, and edge regions, as shown in Figures 12B–D. When the objective lens was adjusted from far to near, clear images of the letter “F” could be observed across the compound eye, from the center to the edge. Similarly, the focus points were clear in all three regions when the objective lens was adjusted from far to near. Figures 12I–K demonstrates the corresponding intensities, with the grayscale intensities of the focal spots being nearly identical on the same focal plane formed by ommatidia at the same distance from the center. Compared to direct laser ablation, this approach significantly improves processing efficiency by more than two orders of magnitude. The combination of dry etching assisted femtosecond laser machining and casting replication technologies holds promising prospects for micro/nanofabrication of hard materials.

Table 2 presents a comparison of microfabrication technologies for miniature curved compound eyes. The technologies were evaluated based on processing efficiency, surface quality, 3D fabrication capacity, and the reported d _o . Among these technologies femtosecond laser direct writing involves scanning the contour point by point, resulting in lower processing efficiency. However, it offers higher 3D flexibility compared to other methods. Surface quality is primarily influenced by the control of stair effects and the self-smoothing effect of materials. Ultra-precision machining, as a true three-dimensional processing method, holds a significant position in microlens manufacturing. Nevertheless, the wear of the tool over time can reduce machining accuracy and increase processing costs. Femtosecond laser wet etching with thermal embossing, modified laser swelling with air-assisted techniques, and inkjet printing with air-assisted microfabrication are all based on bending the flexible planar compound eye using physical force. The mold reproduction method enhances machining efficiency for planar compound eyes, but it limits the contour of curved compound eyes to simple curved surfaces due to the expansion caused by physical forces. Jet printing with electrohydrodynamics is a non-contact printing technology that employs an electric field to trigger ink injection onto the substrate. Surface quality mainly depends on material shrinkage before and after curing. Femtosecond laser-enhanced wet and dry etching can produce fine molds with a certain level of 3D complexity. Surface quality relies primarily on the mold’s surface quality and the material surface’s adhesion.

A series of solutions have been proposed for planar photoelectric detection, for example, focal distance-tunable flexible materials (Ma et al., 2019), self-writing waveguide (Kim et al., 2005), optical fiber guidance (Liu et al., 2019), refractive lens array (Li and Yi, 2012; Jing et al., 2021), multiple spherical microlenses array (Jing et al., 2022) and so on.

A double-layer curved compound eye (DLCCE) was proposed by (Jing et al., 2022) to solve the existing problems. For each ommatidium, a corresponding modified microlens was designed to refract and focus the incident rays on the photoelectric detector. The structure of the double-layer curved compound eye is shown in Figure 13A. The DLCCE was fabricated by two-photon polymerization microfabrication technology. The fabrication processing is shown in Figure 13B. Figures 13C, D show the partial enlarged detail of a through-hole and ommatidia, respectively. The imaging comparisons of single-layer curved compound eye (SLCCE) and DLCCE are shown in Figures 13F–I. Figures 13F, H show the imaging of “I” and “T” of SLCCE, respectively, the imaging of “I” and “T” of DLCCE are shown in Figures 13G, I. The DLCCE shows a uniform light intensity at each level (Jing et al., 2021). Although two-photon polymerization microfabrication can achieve the integrated fabrication of double-layer microlens directly, the imaging quality also suffers from processing errors of two layers.

Furthermore, an ultra-compact micro multi-spherical compound eye (MSCE) was proposed to achieve the focus on the planar photoelectric detector. The structure of the MSCE is shown in Figure 14A. Through adjusting the structural distance along the optical axis of each ommatidium at each level, it can achieve the synchronous focus of all the ommatidia on the planar photoelectric detector with a single-layer compound eye, but without additional adjustable components. The MSCE was fabricated by two-photon polymerization technology. The fabrication processing is shown in Figure 14B. SEM image of the compound eye is shown in Figure 14C. The image of single-spherical compound eye (SSCE) in Figure 14D was used to compare with MSCE. Figures 14E–G show the imaging of “T,” “U,” “C” detected by MSCE. The results show relatively good imaging quality at the edge of MSCE, and the intensity is uniform at each level (Jing et al., 2022). The MSCE structure requires a high 3D controllability of microfabrication technology.

Hu et al. (2022) also proposed a miniature photoelectric compound eye camera (μ-CE) for planar sensors (Hu et al., 2022). The camera utilizes a uniformly logarithmic profile, as depicted in Figure 15A, eliminating the need to calculate the focal lengths of individual small eyes. This facilitates the design and manufacturing process, even with an increased number of compound eyes. Unlike spherical compound eyes, shown in Figure 15B, the logarithmic configuration of μ-CE extends the focusing range, albeit resulting in slight dimming of the image. Nonetheless, this unique focusing characteristic effectively eliminates defocus issues, as shown in Figures 15C, D. The μ-CE has a compact structural size of approximately 400 μm, similar to that of a mosquito’s compound eye, and weighs only 230 mg. Additionally, it enables wide-angle imaging up to 90°, which is crucial for object recognition and trajectory detection in space, as demonstrated in Figures 15E–G. Due to its small size and excellent imaging capabilities, the μ-CE can be seamlessly integrated with microfluidic devices for live microorganism detection, as displayed in Figures 15H–J. Furthermore, M.C. Ma et al. designed a single-pixel superimposed compound eye system (SPSCE) with integrated microlenses, optical fibres and photoreceptors to reduce the complexity of optical design and develop an artificial superimposed compound eye system with higher imaging resolution Ma et al. (2021).

Besides adjusting the microlens array, the development of curved photoelectric detectors is another effective approach to enable simultaneous imaging of all the ommatidia within the curved compound eye.

D. Floreano et al. presented a miniature curved artificial compound eye with flexible printed circuit board, the layers of the curved compound eye are shown in Figure 16A Floreano et al. (2013). The design consists of three layers of arrays: a microlens array, a photoelectric detector array and a curved flexible imager. Figure 16B illustrates the precise alignment and assembly process. Figure 16C demonstrates the dicing of the assembled array into columns, down to the flexible interconnection layer, which remains undamaged. Figure 16D depicts the curvature of the ommatidial array. The designed artificial compound eye bearing a hemispherical field of view with embedded and programmable low-power signal processing, high temporal resolution, and local adaptation to illumination. Y.M. Song et al. presented a camera design inspired by arthropods, featuring nearly full hemispherical shapes Song et al. (2013). The surface of the digital camera is densely populated with imaging elements, with 180 artificial ommatidia, comparable to the eyes of fire ants and bark beetles.

The purpose of bionic compound eyes is to replicate the structures, characteristics, and behaviors of natural compound eyes, with the aim of providing valuable insights for designing innovative optical systems applicable to various facets of manufacturing and daily existence. The utilization of artificial compound eyes has found widespread application across diverse domains, owing to their advantageous attributes such as an expansive field of view, heightened sensitivity, boundless depth of field, and other remarkable features. These domains encompass large FOV perception (Huang et al., 2014; Cogal and Leblebici, 2017; Wang et al., 2019), fast recognition (Shi et al., 2017; Xu et al., 2020), high depth of field (DOF) perception (Kagawa et al., 2012a; Lee and Lee, 2018), spectral perception (Rui et al., 2004; Jin et al., 2013; Chen et al., 2017; Cao et al., 2019; Yu et al., 2020; Zhang et al., 2021), polarization imaging (Kagawa et al., 2012b; Kagawa et al., 2012c; Miyata et al., 2020), and numerous others.

Over the course of previous decades, significant advancements have been made in the research of artificial compound eyes pertaining to the design of their structures, fabrication techniques, and optical capabilities. Despite these successes, there is still significant room for improvement in artificial compound eyes. The prospects of four anticipated research focus on compound eye especially for curved compound eye are presented as follows.

1) Multi-material integrated manufacturing

Achieving a fully functional compound eye imaging system requires the replication of various components such as the cornea, crystalline cone, pigment cell, rhabdom, and retinula cell. Currently, research efforts are focusing on the precise manufacturing of compound eye lenses, which play a crucial role in image formation. However, to create a comprehensive and autonomous compound eye visual apparatus, it is necessary to integrate multiple components of the imaging system. This integration can be achieved through multi-material integrated manufacturing techniques. By utilizing this approach, different materials can be combined and fabricated together, resulting in a more seamless and efficient assembly of the compound eye imaging system. Multi-material integrated manufacturing allows for the precise placement and alignment of different components, reducing errors that may occur during subsequent assembly processes. This integration enhances the overall performance of the compound eye imaging system and improves its functionality as a whole. By replicating and integrating the various components accurately, researchers aim to create a fully functional, autonomous compound eye visual apparatus that can provide unique imaging capabilities, mimic the natural vision of insects, and find applications in fields like robotics, surveillance, and medical imaging.

Continued research and advancements in multi-material integrated manufacturing techniques will contribute to the development of more sophisticated compound eye imaging systems, bringing us closer to achieving a comprehensive and autonomous visual apparatus based on the principles of compound eyes.

2) Mass production of complex 3D compound eyes

The current mass production of compound eyes relies heavily on mold technology, which has limited three-dimensional controllability. This can restrict the level of precision and flexibility in manufacturing the compound eyes. To address this limitation, advanced 3D forming technologies for compound eyes with higher three-dimensional controllability are still required. These technologies aim to provide more precise and flexible manufacturing processes for compound eyes, allowing for improved functionalities and performance. By utilizing advanced 3D forming technologies, manufacturers can enhance the controllability of the compound eye’s three-dimensional structure, leading to better replication of the natural optical properties and functionalities of compound eyes.

This has significant industrial values in applications such as imaging systems, optical sensors, and other fields where the unique capabilities of compound eyes are desired. Continued research and development in this area can potentially drive advancements in manufacturing techniques, enabling the mass production of compound eyes with higher precision, performance, and industrial applicability.

3) High-stability material compound eye manufacturing technology

The current micro-compound eye structures made primarily of organic or organic-inorganic hybrid materials have indeed shown excellent performance. However, to overcome the limitations in corrosion resistance, heat resistance, mechanical strength, and high damage threshold, the utilization of high stability materials in manufacturing technology is of utmost importance. High stability materials offer enhanced properties in terms of corrosion resistance, heat resistance, mechanical strength, and high damage threshold, which are critical for the practical application of micro-compound eyes in engineering fields. These materials, such as advanced ceramics, engineered alloys, or innovative polymer composites, can provide the necessary durability and stability required for demanding applications. By incorporating high stability materials into the manufacturing process of micro-compound eyes, their performance and applications can be significantly improved. Researchers and engineers are actively exploring and developing new materials and manufacturing techniques to enhance the properties of micro-compound eyes and expand their potential uses in various engineering applications.

The pursuit of manufacturing technology using high stability materials is indeed essential for advancing the development and integration of micro-compound eyes in practical engineering applications. Continued research, collaboration, and innovation in this area will ultimately enable us to overcome the existing limitations and fully unlock the potential of micro-compound eyes.

4) Miniaturized high-resolution curved sensors

Commercially available photoelectric sensors are primarily planar sensors. However, the development of miniaturized high-resolution curved surface sensors has the potential to bring about significant improvements in various performance aspects of compound eye imaging systems. Curved surface sensors, also known as curved image sensors, are designed to mimic the structure of natural compound eyes found in insects and some other organisms. These sensors feature a curved shape that allows for a larger field of view and improved image resolution compared to traditional planar sensors. The main advantage of curved surface sensors is that each pixel on the sensor is oriented towards the center of the curved surface. This means that light rays from different angles can be more accurately captured by the individual pixels, resulting in improved imaging accuracy and a higher resolution across the entire field of view. The curved shape also reduces image distortion and glare, leading to better image quality. In addition to improved resolution and imaging accuracy, curved surface sensors can also offer faster response speeds. By curving the sensor, the distance between the lens and the pixels can be reduced, resulting in shorter optical paths and faster image capture.

Overall, the development of miniaturized high-resolution curved surface sensors has the potential to revolutionize imaging technology by significantly improving the performance of compound eye imaging systems. These sensors can enhance resolution, imaging accuracy, response speed, and other crucial aspects, opening up new possibilities in various industries such as robotics, medical imaging, and surveillance.