• Korean Journal of Optics and Photonics
• /
• v.16 no.3
• /
• pp.225-234
• /
• 2005

In the integral imaging system for 3D display, the elemental image size is closely related to the several variables, such as the size of elemental lens, the distance between elemental lens and elemental image, etc., on the pick up system. We have analyzed the geometric relation between the variables. In addition, we have investigated the integrated image variation for the individual and whole conversion of the size of the elemental images, different from in pick up process, and presented experimental results.

• Korean Journal of Optics and Photonics
• /
• v.27 no.1
• /
• pp.41-46
• /
• 2016

An optical method to measure the three-dimensional (3D) shape of a surface with specular reflection is proposed. The proposed method is based on the analysis of the geometric path of the light from a point source, and the relative displacements of points in the reflection image. The 3D shape of a concave mirror is shown to be determined approximately via experiments, where the vision system consists of LED array illumination, a half-mirror, and an imaging sensor.

• Transactions of the Korean Society of Mechanical Engineers
• /
• v.16 no.6
• /
• pp.1030-1035
• /
• 1992

This paper presents a non-contact type displacement sensor designed based on optical triangulation method. The optical principles of the sensor are described in detail with aids of paraxial geometric optics. A prototype sensor is designed and fabricated by using modern optoelectronic hardware. Its measuring performances are evaluated and discussed through a series of calibration processes.

• 한국정보디스플레이학회:학술대회논문집
• /
• 2009.10a
• /
• pp.443-446
• /
• 2009

In this paper, an accurate ray-tracing based visual analysis method of lenticular 3D liquid liquid crystal display (LCDs) and some analysis results are presented. In the developed method, the geometric optics analysis is performed on the single 3D unit pixel of 3D lenticular LCD. It is shown that the display characteristics of 3D lenticular LCD panels of arbitrary size can be evaluated through the 3D unit pixel analysis. The analysis results of a few representative structures of 3D lenticular LCDs are compared.

• Journal of applied mathematics & informatics
• /
• v.11 no.1_2
• /
• pp.1-57
• /
• 2003

Vector fields in three-space admit bundles of internal variables such as a Heisenberg algebra bundle. Information transmission along field lines of vector fields is described by a wave linked to the Schrodinger representation in the realm of time-frequency analysis. The preservation of local information causes geometric optics and a quantization scheme. A natural circle bundle models quantum information visualized by holographic methods. Features of this setting are applied to magnetic resonance imaging.

• Korean Journal of Optics and Photonics
• /
• v.33 no.1
• /
• pp.35-44
• /
• 2022

Since optical systems are used for various applications, there are many designs, depending on the purpose and optical specifications, even though they have similar formations. Optical aberrations of a system are affected by both structure and specifications. Thus, it is very difficult to find the special characteristics of an optical design by using aberration analysis only. Regardless of specifications, a new method to investigate the aberration characteristics of an optical design is presented, using dimensionless design parameters. Four kinds of triplet designs with different applications and specifications are analyzed as examples.

• Current Optics and Photonics
• /
• v.8 no.2
• /
• pp.170-182
• /
• 2024

The dimensional accuracy and consistency of a dual oil circuit centrifugal fuel nozzle are important for fuel distribution and combustion efficiency in an engine combustion chamber. A point cloud measurement method was proposed to solve the geometric accuracy detection problem for the fuel nozzle. An improved variance focus measure operator was used to extract the depth point cloud. Compared with other traditional sharpness evaluation functions, the improved operator can generate the best evaluation curve, and has the least noise and the shortest calculation time. The experimental results of point cloud slicing measurement show that the best window size is 24 × 24 pixels. In the height measurement experiment of the standard sample block, the relative error is 2.32%, and in the fuel nozzle cone angle measurement experiment, the relative error is 2.46%, which can meet the high precision requirements of a dual oil circuit centrifugal fuel nozzle.

• Current Optics and Photonics
• /
• v.8 no.4
• /
• pp.375-381
• /
• 2024

In this report, we present the design, fabrication, and experiment of a static solar system for electric vehicle (EV) applications. The static concentration component is composed of compound parabolic concentrators (CPCs) couplings with multi-junction solar cells, where a flat silicon panel is added to the bottom of the CPV structure to maximize power generation. This design allows the system to collect both direct sunlight and diffused sunlight. The CPCs were fabricated with acrylic with a geometric concentration ratio of 4×. We built a prototype with a (3 × 3) cell array of CPCs with a thickness of 25 mm, which is as thin as conventional flat photovoltaic panels, and performed an outdoor experiment that showed that after six hours of operation, the system had an acceptance angle of approximately 43° and an average daily efficiency of 22.85%.

• Atmosphere
• /
• v.31 no.1
• /
• pp.113-141
• /
• 2021

The impacts of ice clouds on the energy budget of the Earth and their representation in climate models have been identified as important and unsolved problems. Ice clouds consist almost exclusively of non-spherical ice crystals with various shapes and sizes. To determine the influences of ice clouds on solar and infrared radiation as required for remote sensing retrievals and numerical models, knowledge of scattering and microphysical properties of ice crystals is required. A conventional method for representing the radiative properties of ice clouds in satellite retrieval algorithms and numerical models is to combine measured microphysical properties of ice crystals from field campaigns and pre-calculated single-scattering libraries of different shapes and sizes of ice crystals, which depend heavily on microphysical and scattering properties of ice crystals. However, large discrepancies between theoretical calculations and observations of the radiative properties of ice clouds have been reported. Electron microscopy images of ice crystals grown in laboratories and captured by balloons show varying degrees of complex morphologies in sub-micron (e.g., surface roughness) and super-micron (e.g., inhomogeneous internal and external structures) scales that may cause these discrepancies. In this study, the current idealized models representing morphologies of ice crystals and the corresponding numerical methods (e.g., geometric optics, discrete dipole approximation, T-matrix, etc.) to calculate the single-scattering properties of ice crystals are reviewed. Current problems and difficulties in the calculations of the single-scattering properties of atmospheric ice crystals are addressed in terms of cloud microphysics. Future directions to develop physically consistent ice-crystal models are also discussed.

• Journal of the Korean Institute of Telematics and Electronics
• /
• v.18 no.5
• /
• pp.35-45
• /
• 1981

An asymptotic solution of electromagnetic waves scattered by a right-angled dielectric wedge for plane wave incidence is obtained. Scattered fields are constructed by waves reflected and refracted from dielectric interfaces (geometric-optical fields) and a cylindrical wave diffracted from the edge. The edge diffracted field is obtained by adding a correction to the edge diffraction of physical optics approximation, where the correction field is calculated by solving a dual series equation amenable to simple numerical calculation. Validity of this result is assured by two limits of relative dielectric constant $\varepsilon$ of the wedge. The total asymptotic field calculated results in a Rawlins' Neumann series solution for small $\varepsilon$, and the edge diffraction pattern is shown to approach that of a perfectly conducting wedge for large $\varepsilon$. Calculated field patterns are presented and the accuracy of physical optics approximation is discussed.