Abstract: A freeform surface included collimation lens is provided, which is designed through a freeform surface design process to provide an integrally-formed unitary structure. The design method includes a step of identifying an optic field pattern of light source, a step of performing graphic analysis of freeform surface tangential vector formula, a step of acquiring freeform surface control point, a step of constructing a three-dimensional model, and a step of performing geometric processing. Through these steps, tangential vectors of control points of each freeform surface are determined and an approximating process or an exact solution process is adopted to determine the coordinates of the points of the freeform surface. Three-dimensional modeling software is then employing to construct an ellipsoid collimation lens, which realizes an optic collimation performance of at least 88% when tested with a circular disk set at a distance of 200 meters and having a diameter of 35 meters.

Abstract: A positioning unit is provided for a computer housing-and-peripheral device assembly that includes a computer housing and a peripheral device. The positioning unit includes a positioning member disposed between the peripheral device and the computer housing, and including a thin plate that is stamped to form a bent spring arm having a first section which extends toward the casing, and a second section which bends from the first section and which extends toward the computer housing.

Abstract: A positioning unit is provided for a computer housing-and-peripheral device assembly that includes a computer housing and a peripheral device. The positioning unit includes a positioning member disposed between the peripheral device and the computer housing, and including a thin plate that is stamped to form a bent spring arm having a first section which extends toward the casing, and a second section which bends from the first section and which extends toward the computer housing.

Abstract: An adjustable pulley assembly includes a fixing plate securely mounted on top of an upper frame of a suspended door, an adjusting seat mounted to the fixing plate, a pulley seat securely attached to the adjusting seat to move therewith, a pulley attached to the pulley seat, and an adjusting bolt. An axle is extended through the pulley, a screw hole in the pulley seat, and a vertical slot in the adjusting seat, and a nut is engaged on a distal end of the axle. An adjusting bolt is extended through a hole in a top plate of the pulley seat and a screw hole in a top plate of the adjusting seat. A distance between the top plate of the pulley seat and the top plate of the adjusting seat is changed when the adjusting bolt is turned.