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Although apodization patterns have been adopted for the analysis of sputtering sources, the analytical solutions for the film thickness equations are yet limited to only simple conditions. Empirical formulations for thin film sputtering lacking the flexibility in dealing with multi-substrate conditions, a suitable cost-effective procedure is required to estimate the film thickness distribution. This study reports a cross-discipline simulation program, which is based on discrete particle Monte-Carlo methods and has been successfully applied to a non-imaging design to solve problems associated with sputtering uniformity. Robustness of the present method is first proved by comparing it with a typical analytical solution. Further, this report also investigates the overall all effects cause by the sizes of the deposited substrate, such that the determination of the distance between the target surface and the apodization index can be complete. This verifies the capability of the proposed method for solving the sputtering film thickness problems. The benefit is that an optical thin film engineer can, using the same optical software, design a specific optical component and consider the possible coating qualities with thickness tolerance, during the design stage.

Fresnel-like prism arrays are designed using geometric ray optics and fabricated on a curved surface according to specific focal length requirements. In this study, the tolerance of Fresnel-like prism structures on arbitrary surfaces was investigated. Compact equations (iterative and non-iterative) based on analytical formulation can be helpful in exploring the sensitivity associated with the fabrication of Fresnel-like structures. The curved surface in this study revealed a linear relationship between maximum angular tolerance and the angle of incident rays. An understanding of such linearity is a key issue in the fabrication of lenses as well as in the sensitivity formulae used for optical structures in the development of next-generation optics.

SUMMARY The finite element method with linear elastic assumption for predicting the intraocular pressure (IOP) readings after reshaping of the corneal structure is demonstrated in the present study. Twelve effective eye measurements in seven subjects were examined using the TOPCON LX-10, a noncontact intraocular pressure measurement technique, before and after laser-assisted in situ Keratomileusis surgery. A linear elastic model was introduced to reduce possible errors from a complicated anisotropic model with uncertain tissue parameters. Linear relationship between the simplified removal depth of laser-assisted in situ Keratomileusis and predicted IOP was expected, and the comparisons between measurements and the predicted model were made. The results indicated that the expected IOP readings are close to the measurement IOP values, while larger errors occur at smaller IOP conditions. In conclusion, the linear elastic finite element approach can already reveal parameters that influence measurement data the most, and the interaction between parameters was higher than we had expected. This helps us to build the confidence on implementing the anisotropic model.Copyright © 2012 John Wiley & Sons, Ltd.

We report an intuitive approach to simulating the performance of the phosphor-based light emitting diode (LED) by using the two-light-sources model for an optimized LED lens. The optimized secondary lens shape is achieved by approaching a uniform energy distribution on the detecting plane. Both the spectrum and spatial apodization of the LED structure are discussed, and the results indicate that the two-light-sources model can solve the misleading design on the phosphor-based LED due to imperfect color mixing of light source, that one can satisfy the highly uniformity requirement for specific applications, such as display backlight or optogenetic.

Spatial light modulator is introduced for cell culturing and related illumination experiment. Two kinds of designs were used. The first type put the cell along with the bio-medium directly on top of the analyzer of the microdisplay and set a cover glass on it to retain the medium environment, which turned the microdisplay into a bio-container. The second type introduced an optical lens system placed below the spatial light modulator to focus the light spots on specific position. Details of the advantages and drawbacks for the two different approaches are discussed, and the human melanocyte cell (HMC) is introduced to prove the feasibility of the concept. Results indicate that the second type is much more suitable than the first for precision required application.

Light emitting diode (LED) has more advantages compared with a traditional incandescent light bulb and a fluorescent lamp, such as small size, low quantity of heat, long life, low power consumption, fast response, plain packaging and ease of develop ment of a frivolous short product. A methodology is proposed to improve the uniformity of the LED illumination system. As a light source in a backlight unit (BLU), the requirement for optical characteristics of a LED is different from highly directional conventional ones. New diffused-type LEDs need to be developed to fulfill the requirement of the BLU industry. A non-spherical lens is designed to optimize uniformity, and a great improvement in uniformity from 28.4 to 64% is demonstrated. In the future, it may used in an LED display to improve the unevenness of illumination.

Liquid crystals have been recognized as practical adaptive optical components for imaging and nonimaging applications. We have studied a liquid crystal lens without power modulation, as distinct from a focus modulating lens, and have simulated the effects of transient birefringence on the energy distribution on the focal plane. Our results indicate that owing to the particular transient spreading energy patterns on the focal plane, a focusing reversal phenomenon takes place during the operation of this lens, and the characteristic of the modulation transfer function (MTF) of this device indicates that this lens can serve as a spatial frequency filter.

Commercialized projection system and the LED without secondary optical lens are serving as the light source for cell illuminating experiments. Feasibilities and the application for these two approaches are discussed.