@article{oai:ir.kagoshima-u.ac.jp:00000706,
 author = {NAMEDA, Naoyoshi and 行田, 尚義},
 journal = {鹿児島大学工学部研究報告, The research reports of the Faculty of Engineering, Kagoshima University},
 month = {Sep},
 note = {A bifocal lens function has been difficult to achieve in a contact lens. As a solution to the problem, a diffraction bifocal contact lens was developed by Freeman in 1982.
This report shows the results of the calculation of light distribution condensed by a diffraction type contact lens. This lens gives near vision focal length by first order subsidiary light, and far vision focal length by Oth order subsidiary light of the refraction power of the lens.
The method followed in this investigation is described as follows.
First, diffraction light intensity was theoretically calculated. In the 2nd step, the shape of the grating was measured using a special micrometer. In the 3rd step, light distribution on the focal plane was calculated according to the dimensions measured and compared with the measurement
of actual lens light distribution.},
 pages = {161--166},
 title = {Calculation of Light Distribution on a Focal Plane of a Contact Lens Carved Fresnel Zone Plate},
 volume = {35},
 year = {1993}
}