{"id":70,"date":"2026-09-26T20:40:45","date_gmt":"2026-09-26T12:40:45","guid":{"rendered":"https:\/\/enochvision.com\/pd-meters\/"},"modified":"2026-09-27T14:06:31","modified_gmt":"2026-09-27T06:06:31","slug":"pd-meters","status":"publish","type":"page","link":"https:\/\/enochvision.com\/pd-meters\/","title":{"rendered":"PD Meters"},"content":{"rendered":"\t\t<div data-elementor-type=\"wp-page\" data-elementor-id=\"70\" class=\"elementor elementor-70\" data-elementor-post-type=\"page\">\n\t\t\t\t<div class=\"elementor-element elementor-element-9531985 e-con-full e-flex e-con e-parent\" data-id=\"9531985\" data-element_type=\"container\" data-e-type=\"container\">\n\t\t\t\t<div class=\"elementor-element elementor-element-1818e81 elementor-widget elementor-widget-html\" data-id=\"1818e81\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"html.default\">\n\t\t\t\t\t<div class=\"ev\"><div class=\"ev-wrap\"><nav class=\"ev-crumb\" aria-label=\"Breadcrumb\"><a href=\"\/\">Home<\/a><span aria-hidden=\"true\">\/<\/span><span aria-current=\"page\">PD Meters<\/span><\/nav><section class=\"ev-cathead\"><div class=\"ev-cathead__main\"><span class=\"ev-eyebrow\">Measuring<\/span><h1 class=\"ev-h1\">PD Meters (Digital Pupilometers)<\/h1><p class=\"ev-lead\">Digital pupilometers for measuring binocular and monocular pupillary distance, for near and far, at the dispensing table.<\/p><\/div><div class=\"ev-cathead__side\"><p class=\"ev-small\">One measuring design in four body and battery versions.<\/p><\/div><\/section><div class=\"ev-facts ev-facts--cat\"><div><span>Models<\/span><b>1 \u00b7 4 versions<\/b><\/div><div><span>Binocular PD<\/span><b>45\u201382 mm<\/b><\/div><div><span>Monocular PD<\/span><b>22.5\u201341 mm<\/b><\/div><div><span>Power<\/span><b>1 or 2 AA batteries<\/b><\/div><\/div><\/div><\/div>\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-5d9dc9f elementor-widget elementor-widget-html\" data-id=\"5d9dc9f\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"html.default\">\n\t\t\t\t\t<div class=\"ev\"><section class=\"ev-section \"><div class=\"ev-wrap\"><div class=\"ev-head2\"><div><span class=\"ev-eyebrow\">The range<\/span><h2 class=\"ev-h2\">CP-32 digital PD meters<\/h2><\/div><\/div><div class=\"ev-models ev-models--2\"><article class=\"ev-model\"><a class=\"ev-model__img\" href=\"\/products\/cp-32a1\/\"><span class=\"ev-model__tag\">Digital PD meter<\/span><span class=\"ev-model__no\">01<\/span><img loading=\"lazy\" src=\"\/wp-content\/uploads\/2026\/09\/cp-32a1-digital-pd-meter-pupilometer.jpg\" alt=\"CP-32A1 digital PD meter with LCD showing right, total and left PD\" width=\"1200\" height=\"1200\" loading=\"lazy\" decoding=\"async\"><\/a><div class=\"ev-model__body\"><h3 class=\"ev-model__name\"><a href=\"\/products\/cp-32a1\/\">CP-32A1<\/a><\/h3><span class=\"ev-small\">Digital PD meter, PD 45\u201382 mm, 8 distances from 30 cm to \u221e.<\/span><dl class=\"ev-spec\"><div><dt>Binocular PD<\/dt><dd>45\u201382 mm<\/dd><\/div><div><dt>Monocular PD<\/dt><dd>22.5\u201341 mm<\/dd><\/div><div><dt>Visual error<\/dt><dd>&lt; 0.5 mm<\/dd><\/div><div><dt>Power<\/dt><dd>2 \u00d7 AA, DC 3 V<\/dd><\/div><\/dl><div class=\"ev-model__btns\"><a class=\"ev-btn ev-btn--sm\" href=\"\/products\/cp-32a1\/\">View details<\/a><a class=\"ev-btn ev-btn--sm ev-btn--ghost\" href=\"\/contact\/?model=CP-32A1\">Ask about CP-32A1<\/a><\/div><\/div><\/article><div class=\"ev-model ev-model--text\"><div class=\"ev-model__body\"><h3 class=\"ev-model__name\">Four versions<\/h3><span class=\"ev-small\">Same measuring ranges and functions; they differ in front panel, battery and size.<\/span><div class=\"ev-tablewrap\"><table class=\"ev-table\"><thead><tr><th scope=\"col\">Model<\/th><th scope=\"col\">Battery<\/th><th scope=\"col\">Size<\/th><th scope=\"col\">Front<\/th><\/tr><\/thead><tbody><tr><th scope=\"row\">CP-32A1<\/th><td>2 \u00d7 AA, DC 3 V<\/td><td>220 \u00d7 150 \u00d7 50 mm<\/td><td>Rotary knob<\/td><\/tr><tr><th scope=\"row\">CP-32B1<\/th><td>2 \u00d7 AA, DC 3 V<\/td><td>220 \u00d7 150 \u00d7 50 mm<\/td><td>Badge<\/td><\/tr><tr><th scope=\"row\">CP-32AT<\/th><td>1 \u00d7 AA, DC 1.5 V<\/td><td>220 \u00d7 160 \u00d7 55 mm<\/td><td>Rotary knob<\/td><\/tr><tr><th scope=\"row\">CP-32BT<\/th><td>1 \u00d7 AA, DC 1.5 V<\/td><td>220 \u00d7 160 \u00d7 55 mm<\/td><td>Badge<\/td><\/tr><\/tbody><\/table><\/div><\/div><\/div><\/div><\/div><\/section><section class=\"ev-section \"><div class=\"ev-wrap\"><div class=\"ev-head2\"><div><span class=\"ev-eyebrow\">Background<\/span><h2 class=\"ev-h2\">Why PD accuracy matters<\/h2><\/div><\/div><div class=\"ev-guide2\"><div class=\"ev-prose\"><h3>How a pupilometer works<\/h3><p>The customer looks into the instrument while the operator lines up a hairline with the light reflex on each cornea. That reflex sits close to where the line of sight crosses the cornea, which is why pupilometers are more repeatable than a ruler. A near setting gives the reading PD.<\/p><h3>Monocular PD<\/h3><p>Faces are rarely symmetrical, so progressives, strong prescriptions and aspheric lenses should be ordered with a PD for each eye. For progressives, 1 mm of monocular PD error narrows the reading area by about 2 mm.<\/p><\/div><div class=\"ev-prose\"><h3>Good practice<\/h3><ol><li>Check the instrument against a known reference.<\/li><li>Seat the forehead rest evenly.<\/li><li>Set far fixation for distance PD, the working distance for near.<\/li><li>Align on each corneal reflex; occlude for monocular readings.<\/li><li>Take every reading twice.<\/li><\/ol><h3>Accuracy evidence<\/h3><p>A study of nine corneal-reflection pupilometers found measurable errors, mainly from poor eye relief and scale friction, and recommended periodic accuracy checks, especially at very small and very large PDs. Another study found an examiner\u2019s PD ruler within about 0.6 mm of a pupilometer on average, and self-measurement far less repeatable.<\/p><\/div><\/div><p class=\"ev-reading\">Background sources: <a href=\"https:\/\/www.2020mag.com\/article\/meet-your-pupilometer\" target=\"_blank\" rel=\"noopener nofollow\">Meet your pupilometer (20\/20 Magazine)<\/a> \u00b7 <a href=\"https:\/\/www.2020mag.com\/article\/monocular-pds\" target=\"_blank\" rel=\"noopener nofollow\">Monocular PDs (20\/20 Magazine)<\/a> \u00b7 <a href=\"https:\/\/pubmed.ncbi.nlm.nih.gov\/22581116\/\" target=\"_blank\" rel=\"noopener nofollow\">McMahon, Irving &amp; Lee, Optometry and Vision Science 2012<\/a><\/p><\/div><\/section><section class=\"ev-section\" id=\"faq\"><div class=\"ev-wrap ev-faq\"><div style=\"display:flex;flex-direction:column;gap:14px\"><span class=\"ev-eyebrow\">Questions<\/span><h2 class=\"ev-h2\">PD meter questions<\/h2><\/div><div class=\"ev-faq__list\"><details class=\"ev-faq__q\" open><summary><h3>Is a pupilometer better than a PD ruler?<\/h3><\/summary><div><p>It is more repeatable, and it gives monocular and near readings directly. A careful examiner with a ruler comes close on binocular PD.<\/p><\/div><\/details><details class=\"ev-faq__q\"><summary><h3>Which version should I order?<\/h3><\/summary><div><p>The measuring functions are the same. Choose one AA battery (AT\/BT) or two (A1\/B1), and the front panel you prefer.<\/p><\/div><\/details><details class=\"ev-faq__q\"><summary><h3>How is near PD measured?<\/h3><\/summary><div><p>Set the near fixation distance and measure, or calculate it from the distance PD, working distance and vertex distance.<\/p><\/div><\/details><details class=\"ev-faq__q\"><summary><h3>Does it need a power socket?<\/h3><\/summary><div><p>No. It runs on AA batteries and switches itself off when not in use.<\/p><\/div><\/details><\/div><\/div><\/section><section class=\"ev-section ev-section--last\"><div class=\"ev-wrap\"><div class=\"ev-band\"><div><b>Adding a PD meter to your counter?<\/b><span class=\"ev-small\">Tell us the version and quantity you need, and we include batteries and packing in the quotation.<\/span><\/div><a class=\"ev-btn\" href=\"\/contact\/\">Discuss your project&nbsp;&nbsp;\u2197<\/a><\/div><\/div><\/section><script type=\"application\/ld+json\">{\"@context\": \"https:\/\/schema.org\", \"@type\": \"BreadcrumbList\", \"itemListElement\": [{\"@type\": \"ListItem\", \"position\": 1, \"name\": \"Home\", \"item\": \"https:\/\/enochvision.com\/\"}, {\"@type\": \"ListItem\", \"position\": 2, \"name\": \"PD Meters\", \"item\": \"https:\/\/enochvision.com\/pd-meters\/\"}]}<\/script><\/div>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t","protected":false},"excerpt":{"rendered":"<p>Home\/PD Meters Measuring PD Meters (Digital Pupilometers) Digital pupilometers for measuring binocular and monocular pupillary distance, for near and far, at the dispensing table. One measuring design in four body and battery versions. Models1 \u00b7 4 versionsBinocular PD45\u201382 mmMonocular PD22.5\u201341 mmPower1 or 2 AA batteries The range CP-32 digital PD meters Digital PD meter01 CP-32A1 [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"_acf_changed":false,"footnotes":""},"class_list":["post-70","page","type-page","status-publish","hentry"],"acf":[],"_links":{"self":[{"href":"https:\/\/enochvision.com\/es\/wp-json\/wp\/v2\/pages\/70","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/enochvision.com\/es\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/enochvision.com\/es\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/enochvision.com\/es\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/enochvision.com\/es\/wp-json\/wp\/v2\/comments?post=70"}],"version-history":[{"count":21,"href":"https:\/\/enochvision.com\/es\/wp-json\/wp\/v2\/pages\/70\/revisions"}],"predecessor-version":[{"id":922,"href":"https:\/\/enochvision.com\/es\/wp-json\/wp\/v2\/pages\/70\/revisions\/922"}],"wp:attachment":[{"href":"https:\/\/enochvision.com\/es\/wp-json\/wp\/v2\/media?parent=70"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}