This study is about the design and simulation of an f-theta lens, one of the main components used in laser printers and laser scanning systems. To design an f-theta lens, the optical paths of the components of the laser scanning unit, the ftheta lens, the cylinder lens, and the collimator lens must be identified. Simulations were performed on the performance of aspherical and beam size optical systems while considering the f-theta lens optical design and optical properties. And while considering the optical design and optical characteristics of the f-theta lens, simulation was conducted on the performance of the optical system for aspherical surface and ray aberrations by location, point spread function, spot diameter, and beam size. Optical system simulation was implemented by applying the collimator lens, polygon mirror, and cylinder lens to the design formula of an f-theta lens using the Code-V and design verification was performed with these results.
In this study, the fracture characteristics of structural adhesives were investigated according to the shape of a DCB and TDCB by using the FEM. First, to obtain the reliability of the finite element method, the experimental and FEM analyses were compared, and the reliability was secured. When the graph of reaction force to displacement on the TDCB test specimen was examined, it was found that the smaller the slope, the stronger the exhibited property sustaining the load to the end of the adhesive surface. Maximum reaction force occurred was just before the adhesive was removed. The shear stress of the specimen exhibited the same characteristics and an equivalent stress. Thus, the data of this study resulting in the fracture characteristics of the structural adhesives for each shape can be applied to the design with durability.
Majority of deformation and ruptures as a result of severe deformation of mechanical structures are due to the existence of cracks or cracks generated through specific situations. These cracks causes stress concentration and eventually ruptures under lower load conditions than they are designed to withstand. In this study, simulation tensile analysis was done by designing compact tension specimen models with the number of holes that existed inside and the materials of the test specimens by focusing on the effects of the cracks. The study results from all the analysis (deformations, equivalent stress and strain energy) confirmed that the specimen models having two holes had better strength characteristics than those with only one hole. Additionally, the durability and strength characteristics of specific mechanical structures against the load improved through appropriate arrangement of holes thereby reducing stress generation. As such the results of this study could be utilized as the basic data for future researches on composite materials and sandwich type homogenous materials. Furthermore, the study results can assist in designing more durable products.