Byoungho Lee

The performance of bio-chemical sensing devices has been greatly improved by the development of surface plasmon resonance (SPR) based sensors. Advancements in micro- and nano-fabrication technologies have led to a variety of structures in SPR sensing systems being proposed. In this review, SPR sensors (from typical Kretschmann prism configurations to fiber sensor schemes) with micro- or nano-structures for local light field enhancement, extraordinary optical transmission, interference of surface

Reconstruction of light profiles with amplitude and phase information, called holography, is an attractive optical technology with various significant applications such as three-dimensional imaging and optical data storage. Subwavelength spatial control of both amplitude and phase of light is an essential requirement for an ideal hologram. However, traditional holographic devices suffer from their restricted capabilities of incomplete modulation in both amplitude and phase of visible light; this

Electromagnetic metamaterials (MMs) and metasurfaces (MSs) are artificial media and surfaces with subwavelength separations of meta-atoms designed for anomalous manipulations of light properties. Owing to large scattering cross-sections of metallic/dielectric meta-atoms, it is possible to not only localize strong electromagnetic fields in deep subwavelength volume but also decompose and analyze incident light signal with ultracompact setup using MMs and MSs. Hence, by probing resonant spectral r

A holographic display system for realizing a three-dimensional optical see-through augmented reality (AR) is proposed. A multi-functional holographic optical element (HOE), which simultaneously performs the optical functions of a mirror and a lens, is adopted in the system. In the proposed method, a mirror that is used to guide the light source into a reflection type spatial light modulator (SLM) and a lens that functions as Fourier transforming optics are recorded on a single holographic record

A computer-generated integral photography system operating with a variable image plane is proposed. In this scheme, the gap between a lens array and a display panel is adjusted in real time. A synchronized elemental image array for real or virtual mode is integrated in front of or behind the lens array. This integration gives an observer an enhanced perception of depth. The proposed method can be applied to animated three-dimensional imaging.

In spite of the many advantages of integral imaging, its narrow viewing angle has been a disadvantage. We propose a method to enhance the viewing angle of integral imaging by opening and shutting each lens in the array (i.e., the elemental lenses) sequentially. We prove our idea by using a mask that has a pattern of an on-off vertical array of apertures. Moving the mask prevents the aliasing of a neighboring lens. Thus image overlap or image flipping is reduced and the viewing angle of the syste

Abstract Spiral phase contrast imaging offers an excellent opportunity to observe non‐labeled biological samples with slight variations in refractive index or thickness. However, the overall system covering previous works is still complex and bulky, hindering miniaturization and compatibility with conventional systems. Furthermore, high‐resolution imaging, particularly for observing biological specimens such as cellular structures, requires several refractive optical elements like objectives and

Displays that reproduce depth in some cases and create its illusion in others vary from the simple to the sophisticated.

Abstract Broadband‐operating active devices within a small‐footprint are highly on demand in various nanophotonic fields such as fiber‐optic communication systems and chip‐based integrated optical circuits. As pioneering approaches, diverse platforms of active metasurfaces (AMs) have been proposed due to their superior tunable functionality and ultra‐compact size. However, most of previous researches provide only limited operating bandwidth because they generally rely on resonant light–matter in

A novel method to launch finite power Airy beams based on a metasurface is presented. By tailoring the amplitude and phase of the transmitted fields from a metallic C‐aperture array, launching Airy beams is achieved in free space. The amplitude and phase of the Airy beam profile can be mapped and tailored by tuning only the tilt angles of the aperture. This structure has multifrequency characteristics, which facilitates Airy beam steering because the trajectory of Airy beams is dependent on the

In this review, an overview of the subwavelength confinement of light with plasmonics is presented. Among the varieties of state-of-the-art technologies on this intensively-studied topic, we focus on the surface plasmon-assisted light enhancement via the single metallic aperture. Based on a systematic overview of the physical principles of light enhancement in subwavelength-sized metallic apertures, we investigate various types of apertures and discuss their characteristics.