Zhiliang Fang

Bio: Zhiliang Fang is an academic researcher from Nankai University. The author has contributed to research in topics: Integral imaging & Grating. The author has an hindex of 8, co-authored 18 publications receiving 223 citations.

Color-coded projection grating method for shape measurement with a single exposure.

Abstract: A fast and efficient technique for profilometric measurement with a color-coded grating is proposed. Eight colors are used to code the grating, and each color represents only one logical state. There are 64 stripes in one period of the color grating, which is large enough for normal measurement. Compared with the previous techniques, it has the advantages of simple hardware without moving mechanical parts, single exposure for obtaining three-dimensional information, little influence from noise and from nonlinearity of the CCD camera on the measurement accuracy, and higher anti-color-blurring capability. The suggested technique is suitable for on-line inspection and dynamic measurement of moving objects.

Illumination system using LED sources for pocket-size projectors

Abstract: An illumination system using LED sources for pocket-size projectors is designed. Its color gamut is much larger than the sRGB standard. The maximum theoretical efficiency of this system is 29.98% by non-imaging theory-based calculations. To analyze the system model, 1.5 × 106 rays are traced by using the LightTools software. The total light flux that illuminates the digital micromirror device is 44 lm and the American National Standards Institute 13-point uniformity on the surface is 91.55%, −91.15% with a system efficiency of 28.3%. The calculations are in good agreement with the simulation results. The illumination system can be used for personal pocket-size projectors providing a 15-20 in. (38-51 cm) color display with the brightness comparable with a laptop.

Hexagonal microlens array fabricated by direct laser writing and inductively coupled plasma etching on organic light emitting devices to enhance the outcoupling efficiency

Abstract: A hexagonal microlens array directly fabricated on an indium tin oxide glass substrate by the combination of direct laser writing and inductively coupled plasma etching is demonstrated to enhance the outcoupling efficiency of the organic light emitting devices, which can avoid the loss of photons and the mechanical and thermal deformations at the glass/microlenses interface. An atomic force microscope measurement indicates the contour of the fabricated hexagonal microlens is nearly an ideal part of a hemisphere. From the comparison with the operating OLED without a microlens array, the outcoupling efficiency is enhanced more than 40% with the hexagonal microlens array on the glass substrate, and the enhanced emission from the active area of the device with the hexagonal microlens array at the viewing angles from 0° to 40° can clearly be seen.

Enhancement of depth-of-field in a direct projection-type integral imaging system by a negative lens array

Abstract: We propose a method for enhancing depth-of-field, in which the spot size on a marginal depth plane is reduced. This method is implemented in a projection-type integral imaging system using a negative lens array without a diffuser. Numerical simulation results show that the spot size is merely 5.7% of that in a conventional system. Thus, the depth-of-field in the proposed system is enhanced by 17.5 times over that in a conventional system. Optical experiments confirm good agreement between the results and numerical predictions.

Generalized approach to modifying optical vortices with suppressed sidelobes using Bessel-like functions

Abstract: We propose a generalized approach to producing optical vortices with suppressed sidelobes using a variable Bessel-like function added to the conventional spiral phase plate. Experimental verifications are implemented by a phase-only spatial light modulator. It is demonstrated that the method is valid for optical vortex beams with arbitrary topological charges and without changing the primary ring size as a unique property among the existing techniques.

Two-photon direct laser writing of ultracompact multi-lens objectives

Abstract: Femtosecond two-photon direct laser writing is used to create 100-µm-scale high-performance multi-lens objectives.

Generation of the "perfect" optical vortex using a liquid-crystal spatial light modulator

Abstract: We introduce the concept of the perfect optical vortex whose dark hollow radius does not depend on the topological charge. It is shown analytically and experimentally that such a vortex can be approximately generated in the Fourier transforming optical system with a computer-controlled liquid-crystal spatial light modulator.

Recent advances in transition metal complexes and light-management engineering in organic optoelectronic devices.

Abstract: Two of the recent major research topics in optoelectronic devices are discussed: the development of new organic materials (both molecular and polymeric) for the active layer of organic optoelectronic devices (particularly organic light-emitting diodes (OLEDs)), and light management, including light extraction for OLEDs and light trapping for organic solar cells (OSCs). In the first section, recent developments of phosphorescent transition metal complexes for OLEDs in the past 3–4 years are reviewed. The discussion is focused on the development of metal complexes based on iridium, platinum, and a few other transition metals. In the second part, different light-management strategies in the design of OLEDs with improved light extraction, and of OSCs with improved light trapping is discussed.