{"id":140,"date":"2018-12-08T15:20:51","date_gmt":"2018-12-08T15:20:51","guid":{"rendered":"http:\/\/www.formulens.com\/?p=140"},"modified":"2023-05-15T04:10:22","modified_gmt":"2023-05-15T04:10:22","slug":"aspheric-back-surface-designs","status":"publish","type":"post","link":"https:\/\/www.formulens.com\/index.php\/2018\/12\/08\/aspheric-back-surface-designs\/","title":{"rendered":"Aspheric Back Surface Designs"},"content":{"rendered":"<p>For high power single-vision lenses, significant improvement can be achieved with freeform lenses, even with spheric blanks. The following plots describe the performance for a surface optimized for a +13 Diopter prescription with CR-39 and\u00a0 a spheric blank.<\/p>\n<p><img decoding=\"async\" loading=\"lazy\" class=\" wp-image-141 aligncenter\" src=\"https:\/\/www.formulens.com\/wp-content\/uploads\/2020\/09\/godesign03_sim13p5.png\" alt=\"\" width=\"516\" height=\"495\" \/><\/p>\n<p><!--more--><\/p>\n<p>As the first plot shows, the aspheric back surface is most strongly curved for a plus lens, resulting in a thinner design.<\/p>\n<p>The next two plots show the improvement in both sphere and cylinder error across the gaze angles. The constant spherical equivalent means there is a constant magnification and hence the image is not distorted.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>For high power single-vision lenses, significant improvement can be achieved with freeform lenses, even with spheric blanks. The following plots describe the performance for a surface optimized for a +13 Diopter prescription with CR-39 and\u00a0 a spheric blank.<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[3,4],"tags":[],"_links":{"self":[{"href":"https:\/\/www.formulens.com\/index.php\/wp-json\/wp\/v2\/posts\/140"}],"collection":[{"href":"https:\/\/www.formulens.com\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.formulens.com\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.formulens.com\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.formulens.com\/index.php\/wp-json\/wp\/v2\/comments?post=140"}],"version-history":[{"count":1,"href":"https:\/\/www.formulens.com\/index.php\/wp-json\/wp\/v2\/posts\/140\/revisions"}],"predecessor-version":[{"id":142,"href":"https:\/\/www.formulens.com\/index.php\/wp-json\/wp\/v2\/posts\/140\/revisions\/142"}],"wp:attachment":[{"href":"https:\/\/www.formulens.com\/index.php\/wp-json\/wp\/v2\/media?parent=140"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.formulens.com\/index.php\/wp-json\/wp\/v2\/categories?post=140"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.formulens.com\/index.php\/wp-json\/wp\/v2\/tags?post=140"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}