• Korean Journal of Optics and Photonics
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• v.5 no.2
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• pp.204-211
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• 1994

Micro array lens systems are designed for a faximile or copy machine. The array type is hexagonal. Diameter of a lens is 0.16 mm and the distance of the center of the nearest neighbor is 0.192 mm. The magnitude of the lens system is 1:1. Working distane is 10.55 mm and the spot size is less than 0.04 mm radius on axis and 0.20 mm off-axis in case of single layer system. Working distance is 7.90 mm and the spot size is less than 0.07 mm radius on axis and 0.09 mm radius off axis in case of double layer system. Performance of single layer micro array lens system and double layer micro array lens system are compared with the characteristics of the ray fans.y fans.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.20 no.2
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• pp.1-7
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• 2006

A light guided plate coupled with the micro Fresnel lens array(MFTA) is designed to improve the efficiency of the LCD backlight unit. Blazed Frenel lens and binary multi-level Fresnel lens are adapted for the MFLA. This type of MFLA can replace the prism sheet and diffuser sheet which are used for the conventional type of the LCD backlight unit. The luminance and uniformity are calculated to verify the performance of the MFLA type LCD backlight unit.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.20 no.4
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• pp.472-477
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• 2011

This paper shows the method of fabrication of a micro lens array comprised of a Nipkow disk used in a large-area, high-speed confocal microscopy. A Nipkow disk has two components, a micro lens array disk and a pinhole array disk. The microlens array focuses illumination light onto the pinhole array disk and redirects reflected light from a surface to a sensor. The micro lens which are positioned in order on a disk have a hemispheric shape with a few tens of micron in diameter, and can be fabricated by a variety of methods like mechanical machining, semiconductor process, replication process like imprinting process. This paper shows how to fabricate the micro lens array which has a long focal length by reflow and imprinting process.

• Korean Journal of Optics and Photonics
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• v.16 no.3
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• pp.217-224
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• 2005

A light-guide plate of an LCD backlight coupled with a microfresnel lens array (MFLA) is designed and analyzed. Computer simulated results of optical characteristics of our MFLA-type light-guided plate compared with the conventional prism-type one are presented. We show that the MFLA-type light-guide plate can replace well the conventional prism-type plate.

• Journal of the Korean Society for Precision Engineering
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• v.25 no.2
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• pp.123-130
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• 2008

A 3D structure production method for microstereolithography is a useful way that produces complex structures with flexible processes and low cost. Several UV curable resins were blended and the optimal resin for micro-lens fabricate was selected through viscosity, workability and transmission tests. It consists of 1, 6 - Hexanediol diacrylate with 15 Apha and Isobornyl acrylate for reducing some shrinkage. When fabricating a micro-lens array on large surface, some distortion of shape occurred because of the surface tension between cured part. To overcome this problem, the optimal processing conditions were derived from considering amount of the resin and surface tension. Large surface Micro-lens array, which are a type of elliptical convex and consist of 18,000 micro-lens in the range of 2cm*2cm were fabricated. The focal length to the X-axis and Y-axis were calculated. To verify the performance, measure an energy distribution of transmitted light from the Large surface Micro-lens array.

• Journal of Institute of Control, Robotics and Systems
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• v.19 no.11
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• pp.979-983
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• 2013

The three-dimensional measurement method of confocal systems is a spot scanning method which has a high resolution and good illumination efficiency. However, conventional confocal systems had a weak point in that it has to perform XY axis scanning to achieve FOV (Field of View) vision through spot scanning. There are some methods to improve this problem involving the use of a galvano mirror [1], pin-hole array, etc. Therefore, in this paper we propose a method to improve a parallel mode confocal system using a micro-lens and pin-hole array in a dual microscope configuration. We made an area scan possible by using a combination MLA (Micro Lens Array) and pin-hole array, and used an objective lens to improve the light transmittance and signal-to-noise ratio. Additionally, we made it possible to change the objective lens so that it is possible to select a lens considering the reflection characteristic of the measuring object and proper magnification. We did an experiment using 5X, 2.3X objective lens, and did a calibration of height using a VLSI calibration target.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.1885-1888
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• 2003

As high technology industries such as IT and display have developed, demand for application parts of micro lens and lens array has been extremely increasing. According to these trends, many researchers are studying on the fabrication technology for parts of the micro lens by a variety of methods such as MEMS, Lithography, LIGA and so on. In this paper, we have performed researches related to ultra precision micro lens, lens array mold and fabrication of Lenticular lens mold for three-dimensional display by using mechanical micro end-milling and fly-cutting fabrication method. Tools used in this research were a diamond tool of R 150$\mu\textrm{m}$. Cutting conditions set up feed rate, spindle revolution. depth of cut and dwell time as variables. And we analyzed surface quality variation of the processed products according to the cutting conditions, and then carried out experiments to search the optimum conditions. Through this research, we have confirmed that we can fabricate the ultra precision micro lens mold with surface roughness Ra=20nm and the holographic lens mold by using micro end-milling and fly-cutting fabrication method. Furthermore, we demonstrated problems happened in the fabrication of the micro lens and established the foundation of experimental study for formulating its improvement plan.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.1497_1498
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• 2009

This paper presents the simulation of micro-lens arrays based on dry and wet etching technique. Code V (Optical Research Associates Ltd) simulation was performed to extract optimal design parameters of a Micro-Lens Array(MLA). Thickness of UV adhesive, wavelength of laser source, curvature, and shape of lens surface were chosen for the design parameters. The simulation results showed that focal length of a MLA decreased with the increase of UV adhesive thickness. And the focal length depended on shape of lens surface and length of laser source.

• Journal of the Korean Society of Industry Convergence
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• v.26 no.4_1
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• pp.517-527
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• 2023

Many techniques have been proposed and investigated for microlens array manufacturing in three-dimensional (3D) structures. We present fabricating a microlens array using selective laser etching and a CO₂ laser. The femtosecond laser was employed to produce multiple micro-cracks that comprise the predesigned 3D structure. Subsequently, the wet etching process with a KOH solution was used to produce the primary microlens array structures. To polish the nonoptical surface to the optical surface, we performed reflow postprocessing using a CO₂ laser. We confirmed that the micro lens array can be manufactured in three primary shapes (cone, pyramid and hemisphere). Compared to our previous study, the processing time required for laser processing was reduced from approximately 1 hour to less than 30 seconds using the proposed processing method. Therefore, micro lens arrays can be manufactured using our processing method and can be applied to mass productionon large surface areas.

• Proceedings of the Optical Society of Korea Conference
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• 2007.02a
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• pp.265-266
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• 2007