• Transactions of Materials Processing
• /
• v.16 no.1 s.91
• /
• pp.25-30
• /
• 2007

The present study covers an integrated simulation method to evaluate optical performance of an aspheric plastic lens by connecting a finite element (FE) analysis of injection molding with a ray tracing simulation. Traditional ray tracing methods have based on the assumption that the optical properties of a lens are homogeneous throughout the entire volume. This assumption is to a certain extent unrealistic for injection-molded plastic lenses because material properties vary at every point due to the injection molding effects. To take into account the effects of the inhomogeneous optical properties of the molded lens, a new.ay tracing scheme is proposed in conjunction with a FE analysis of the injection molding. A numerical scheme is developed to calculate ray paths on every element layer with more realistic information of the refractive indices which can be obtained through the FE analysis. This information is then used to calculate the ray paths based on the FE mesh of which nodal points have unique index values. The proposed tracing scheme is implemented on the tracing of an aspheric lens, and its validity is ascertained through experimental verification.

• Transactions of Materials Processing
• /
• v.20 no.1
• /
• pp.54-59
• /
• 2011

Optical properties in injection molded plastic lenses for mobile phone camera have been simulated using commercial program, 3D TIMON. Four plastic lenses are being used in mobile phone camera. The quality of photographs taken by mobile phone camera is strongly depends upon optical characteristics of lenses. The variety of optical properties has been investigated according to the injection conditions through the computer simulation. Consequently optimal injection conditions for four lenses have been determined and simulation results of birefringence have been compared with experiments.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2005.07a
• /
• pp.459-460
• /
• 2005

The global consumption of aspheric surfaces will expand rapidly on the Electronics and Optical Components, Information and Communications, Aerospace and Defense, and Medical optics markets etc. We must research on market, technology forecast and analysis of aspheric surfaces that is a principle step of ultra precision machine technology with a base one of optical elements. Especially, F-theta lens is one of the important parts in LSU(Laser scanning unit) because it affects on the optical performance of LSU dominantly. The core is most of important to produce plastic F-theta lens by plastic injection molding method, which is necessary to get the ultra-precision aspheric and non-axisymmetric machine processing technology.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2005.10a
• /
• pp.777-780
• /
• 2005

The global consumption of aspheric surfaces will expand rapidly on the Electronics and Optical Components Information and Communications, Aerospace and Defense, and Medical optics markets etc. We must research on market, technology forecast and analysis of aspheric surfaces that is a principle step of ultra precision machine technology with a base one of optical elements. Especially, F-theta lens is one of the important parts in LSU(Laser scanning unit) because it affects on the optical performance of LSU dominantly. The core is most of important to produce plastic F-theta lens by plastic injection molding method, which is necessary to get the ultra-precision aspheric and non-axisymmetric machine processing technology.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2013.05a
• /
• pp.97-98
• /
• 2013

• Korean Journal of Optics and Photonics
• /
• v.9 no.5
• /
• pp.291-299
• /
• 1998

In the rear projection TV, the optimal system configurations of optical parts are presented, which are focused on competitive price and performances. From the initial design with five Seidel aberrations free, aspherization of the plastic lenses, and optimization with tolerances, a new lens consisting of two plastic and one glass lenses was designed. It is able to be used on current broadcast standard NTSC and digital TV in common. The developed CRT-lens assembly could display the 40 to 50 inch image and its resolution is more than 800 TV-lines.

• Journal of the Optical Society of Korea
• /
• v.19 no.2
• /
• pp.182-187
• /
• 2015

This paper presents a new graphical method for selecting a pair of optical glasses to simultaneously achromatize and athermalize an imaging lens made of materials in contact. An athermal glass map that plots thermal glass constant versus inverse Abbe number is derived through analysis of optical glasses and plastic materials in visible light. By introducing the equivalent Abbe number and equivalent thermal glass constant, although it is a multi-lens system, we have a simple way to visually identify possible optical materials. Applying this method to design a phone camera lens equipped with quarter inch image sensor having 8-mega pixels, the thermal defocuses over $-20^{\circ}C$ to $+60^{\circ}C$ are reduced to be much less than the depth of focus of the system.

• Journal of the Korean Graphic Arts Communication Society
• /
• v.20 no.1
• /
• pp.113-122
• /
• 2002

We designed the illumination optical system to use Fresnel lens which is the most general type of large aperture system. The normal construction of Fresnel lens is a thin molded piece of material, usually some kind of plastic, with one side flat and the other comprising a series of concentric segments each angled in a way to provide for optimum focusing for a pair of conjugate points. The 155 mm Marine Signal Lantern is the approved for use on buoys and a maximum omnidirectional range of 8 nmi, can be obtained with standard 12V equipment, respectively. Finally, Fresnel lens with 155 mm diameter was designed and evaluated. Also, we re-designed groove "out" of Fresnel lens and compared results of groove "in" type with groove "out" type. According to the results, Fresnel lens is obtained best optical results when grooved side faces the longer conjugate.de faces the longer conjugate.

• 한국신재생에너지학회:학술대회논문집
• /
• 2007.11a
• /
• pp.245-245
• /
• 2007

• Transactions of the Korean Society of Machine Tool Engineers
• /
• v.17 no.4
• /
• pp.112-118
• /
• 2008

In order to meet the optical performance in the process of the micro lens manufacturing with plastics, it is important to embody accuracy in shape and surface roughness to the intended design. Since it is difficult to machine exactly the mold core of lens fit to the designed shape, in this paper, a simple program using MATLAB is developed for shape correction of the mold core after first machining it. This program evaluates correction parameters(aspheric coefficients and curvature) and generates aspheric NC data for compensating the core surface in prior machining process. The program provides the way to manufacture plastic injection molding lens with aspheric shape of high precision, and is expected to be effective for correction and to shorten the processing time.