Nanofabrication Techniques: Challenges and Future Prospects.

Nanofabrication of functional micro/nano-features is becoming increasingly relevant in various electronic, photonic, energy, and biological devices globally. The development of these devices with special characteristics originates from the integration of low-cost and high-quality micro/nano-features into 3D-designs. Great progress has been achieved in recent years for the fabrication of micro/nanostructured based devices by using different imprinting techniques. The key problems are designing techniques/approaches with adequate resolution and consistency with specific materials. By considering optical device fabrication on the large-scale as a context, we discussed the considerations involved in product fabrication processes compatibility, the feature's functionality, and capability of bottom-up and top-down processes. This review summarizes the recent developments in these areas with an emphasis on established techniques for the micro/nano-fabrication of 3-dimensional structured devices on large-scale. Moreover, numerous potential applications and innovative products based on the large-scale are also demonstrated. Finally, prospects, challenges, and future directions for device fabrication are addressed precisely.

Fiber-bundle illumination: realizing high-degree time-multiplexed multifocal multiphoton microscopy with simplicity.

High-degree time-multiplexed multifocal multiphoton microscopy was expected to provide a facile path to scanningless optical-sectioning and the fast imaging of dynamic three-dimensional biological systems. However, physical constraints on typical time multiplexing devices, arising from diffraction in the free-space propagation of light waves, lead to significant manufacturing difficulties and have prevented the experimental realization of high-degree time multiplexing. To resolve this issue, we have developed a novel method using optical fiber bundles of various lengths to confine the diffraction of propagating light waves and to create a time multiplexing effect. Through this method, we experimentally demonstrate the highest degree of time multiplexing ever achieved in multifocal multiphoton microscopy (~50 times larger than conventional approaches), and hence the potential of using simply-manufactured devices for scanningless optical sectioning of biological systems.

Three-dimensional visualization system for ophthalmic microscopes using visible light and near-infrared illumination.

In this paper, we describe a three-dimensional visualization system for ophthalmic microscopes that is aimed at microsurgery without the eyepieces. A three-dimensional visualization system for ophthalmic microscopes using the mixed illumination, which consists of visible light and near-infrared illumination, is established in order to acquire more exact information of object and reduce the amount of light irradiated to the patients, and its usage in microsurgery without eyepieces is herein described. A custom-designed stereoscopic three-dimensional display which is manufactured for the convenience of the surgeons during the long-time surgery, is connected directly to the camera of the ophthalmic microscope in order to eliminate the discomfort of eyepieces to the surgeon and signal delay between the camera, mounted on the microscope, and display device for surgeon. The main features of the established system are the signal delay-free for surgeon and the low level of illumination for patient. In particular, it could significantly reduce the amount of light irradiated on a patient's eye via NIR illumination. Upon comparison with the conventional system during clinical ophthalmology trials, this system is confirmed to require almost the same operation time and reduced discomfort and eyestrain during long periods of observation.