Author
Guoguang Mu
Bio: Guoguang Mu is an academic researcher from Nankai University. The author has contributed to research in topics: Grating & Diffraction efficiency. The author has an hindex of 10, co-authored 70 publications receiving 400 citations.
Papers published on a yearly basis
Papers
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TL;DR: It is shown that the two deconvolution methods can deblur the experimentally obtained optical coherence tomography images effectively.
Abstract: Two-dimensional deconvolution methods are proposed to deblur optical coherence tomography images. One employs a two-dimensional deconvolution with a matrix given by the product of the longitudinal and transversal point-spread functions as its kernel, which can be taken as the general point-spread function of an optical coherence tomography system. The other uses two one-dimensional deconvolutions with the longitudinal and transversal point-spread functions successively. It is shown that the two deconvolution methods can deblur the experimentally obtained optical coherence tomography images effectively.
82 citations
TL;DR: A fast and efficient technique for profilometric measurement with a color-coded grating that 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.
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.
72 citations
TL;DR: The illumination system can be used for personal pocket-size projectors providing a 15-20 in.
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.
33 citations
TL;DR: Liou et al. as discussed by the authors transformed a human eye model based on anatomically accurate eye model into a new eye model, in which laminated structure of the lens is considered.
25 citations
TL;DR: Two hybrid optical/digital systems for access control applications in real-time fingerprint identification are presented, and initial experimental results show that the incoherent system achieves better performance at the expense of additional equipment.
Abstract: Two hybrid optical/digital systems for access control applications in real-time fingerprint identification are presented. Both involve fingerprint acquisition with a prism, optical Fourier transformation by a lens, data reduction using a wedge-ring detector (WRD), and decision making with a digital computer. One, called the coherent system, performs the Fourier transformation on a coherent fingerprint image introduced directly from a prism, and the other, called the incoherent system, acquires an incoherent fingerprint image, performs preprocessing in a digital computer, and incoherent-to-coherent image conversion before coherent processing. Both systems use the total internal reflection obtained in a prism to introduce the fingerprint image. Decision making is performed by a computer on the WRD output, a feature vector of 64 component digital values. In our experiment, discrimination and error-tolerance performance associated with our two access control systems were tested with four different fingerprints. Initial experimental results show that the incoherent system achieves better performance at the expense of additional equipment.
19 citations
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TL;DR: This paper presents a meta-analyses of Fourier-Transform Profilometry and its applications in 3-D Shape Measurement and Surface Profile Measurement for Structured Light Pattern and 4-Core Optical-Fiber.
1,110 citations
TL;DR: The various applications of neural networks in image processing are categorised into a novel two-dimensional taxonomy for image processing algorithms and their specific conditions are discussed in detail.
1,100 citations
TL;DR: After the invention of lasers, in the past 50 years progress made in laser-based display technology has been very promising, with commercial products awaiting release to the mass market.
Abstract: After the invention of lasers, in the past 50 years progress made in laser-based display technology has been very promising, with commercial products awaiting release to the mass market. Compact laser systems, such as edge-emitting diodes, vertical-cavity surface-emitting lasers, and optically pumped semiconductor lasers, are suitable candidates for laser-based displays. Laser speckle is an important concern, as it degrades image quality. Typically, one or multiple speckle reduction techniques are employed in laser displays to reduce speckle contrast. Likewise, laser safety issues need to be carefully evaluated in designing laser displays under different usage scenarios. Laser beam shaping using refractive and diffractive components is an integral part of laser displays, and the requirements depend on the source specifications, modulation technique, and the scanning method being employed in the display. A variety of laser-based displays have been reported, and many products such as pico projectors and laser televisions are commercially available already.
330 citations
TL;DR: The current state-of-the-art in structured light profilometry systems is described, as well as the main advancements in hardware technology and coding strategy that have led to their successful development.
286 citations
TL;DR: The proposed wide-field schematic eye model incorporates a gradient-index (GRIN) lens, which enables it to fulfill properties of two well-known schematic eye models, namely, Navarro's model for off-axis aberrations and Thibos's chromatic on-axis model.
Abstract: We propose a wide-field schematic eye model, which provides a more realistic description of the optical system of the eye in relation to its anatomical structure. The wide-field model incorporates a gradient-index (GRIN) lens, which enables it to fulfill properties of two well-known schematic eye models, namely, Navarro's model for off-axis aberrations and Thibos's chromatic on-axis model (the Indiana eye). These two models are based on extensive experimental data, which makes the derived wide-field eye model also consistent with that data. A mathematical method to construct a GRIN lens with its iso-indicial contours following the optical surfaces of given asphericity is presented. The efficiency of the method is demonstrated with three variants related to different age groups. The role of the GRIN structure in relation to the lens paradox is analyzed. The wide-field model with a GRIN lens can be used as a starting design for the eye inverse problem, i.e., reconstructing the optical structure of the eye from off-axis wavefront measurements. Anatomically more accurate age-dependent optical models of the eye could ultimately help an optical designer to improve wide-field retinal imaging.
156 citations