Freeform Design: Progressive Addition Lens
Date Issued
2010
Date
2010
Author(s)
Liu, Yen-Liang
Abstract
Optical systems are composed by various of optical elements, such as lenses and mirrors. In order to achieve different purpose, positions, materials, and surface shapes of the optical elements can be regulated. Among these specifications, regulating surface shapes of the optical elements is an issue that is worth researching. In early age, the surface shapes of lens or mirrors are spherical. For the sake of decreasing optical aberrations or other purpose, aspherical or freeform surfaces may be adapted. Although it is more difficult to design or manufacture, progress of computer power and manufacture technology have made the applications of aspherical and freeform elements more and more various. In order to achieve better performance of optical systems, designing aspherical and freeform surfaces are worth more concerns.
In the thesis, freeform surfaces are applied to progressive Addition lenses (PAL), A PAL can combine different requirements of diopter on one lens, avoiding the necessity of a presbyopic changing different pairs of spetacles while viewing far side and near side. B-spline surfaces are used to describe the freeform surfaces applied on PALs in the thesis. The designs are achieved by optimization. Sample PALs are also produced and measured to show the feasibility. The simulation and measurement result shows that the performance of view zone area and cylinder are equal or even better to modern products.
Subjects
Freeform
Progressive Addition Lens
PAL
B-spline Surface
Optimization
Presbyopia
Type
thesis
File(s)![Thumbnail Image]()
Loading...
Name
ntu-99-R97941030-1.pdf
Size
23.32 KB
Format
Adobe PDF
Checksum
(MD5):68cb48431261e5d687afd3c8d284f0ec