{"id":65885,"date":"2026-09-30T13:56:42","date_gmt":"2026-09-30T10:56:42","guid":{"rendered":"https:\/\/wpcalc.com\/en\/?p=65885"},"modified":"2026-09-30T13:56:42","modified_gmt":"2026-09-30T10:56:42","slug":"thin-lens-equation-calculator","status":"publish","type":"post","link":"https:\/\/wpcalc.com\/en\/physics\/thin-lens-equation-calculator\/","title":{"rendered":"Thin Lens Equation Calculator"},"content":{"rendered":"<section class=\"not-prose calculator-box\" aria-labelledby=\"calculator-title\"><div class=\"flex items-baseline sm:items-center justify-between gap-2 sm:gap-3\"><div class=\"flex flex-col sm:flex-row sm:items-center gap-2\"><span class=\"icon icon-calculator text-primary-700! text-base! dark:text-primary-300!\" aria-hidden=\"true\"><\/span><h2 id=\"calculator-title\" class=\"text-lg font-display font-bold\">Find the Missing Distance or Focal Length<\/h2><\/div><div class=\"calcdash-favorite group\">\n  <button type=\"button\" class=\"favorite\" id=\"favorite\" data-favorite-id=\"65885\" data-favorite-title=\"Lens Equation\" data-favorite-url=\"https:\/\/wpcalc.com\/en\/physics\/thin-lens-equation-calculator\/\" data-favorite-excerpt=\"Solve the thin lens equation 1\/f = 1\/do + 1\/di for image distance, object distance or focal length. Enter any two known values and get the third, plus image type, magnification and image height.\" aria-label=\"Add to Favorites\" data-favorite-icon=\"icon icon-spectrum\">\n    <span class=\"icon icon-shape-star-empty\" aria-hidden=\"true\"><\/span>\n  <\/button>\n  <div class=\"calcdash-favorite__tip\" aria-hidden=\"true\">\n   <span class=\"favorite-tooltip\" id=\"favorite-tooltip\"><\/span>\n  <\/div>\n  <span class=\"sr-only\" role=\"status\" id=\"favorite-status\"><\/span>\n<\/div><\/div><form action=\"https:\/\/wpcalc.com\/en\/physics\/thin-lens-equation-calculator\/\" method=\"POST\" class=\"calculator\" id=\"calculator-65885\" data-post=\"65885\"><fieldset class=\"fieldset-input is-1\"><legend class=\"sr-only\">Input Fields<\/legend><div class=\"field is-single\" id=\"input-1\"><label for=\"field-1\">Solve for<\/label><div class=\"grid grid-cols-1\"><select id=\"field-1\" name=\"solve_for\"><option value=\"di\" selected>Image distance (d\u1d62)<\/option><option value=\"do\">Object distance (d\u2092)<\/option><option value=\"f\">Focal length (f)<\/option><\/select><svg class=\"pointer-events-none col-start-1 row-start-1 mr-2 size-5 self-center justify-self-end text-gray-500 sm:size-4\" viewBox=\"0 0 16 16\" fill=\"currentColor\" aria-hidden=\"true\" data-slot=\"icon\">\n              <path fill-rule=\"evenodd\" d=\"M4.22 6.22a.75.75 0 0 1 1.06 0L8 8.94l2.72-2.72a.75.75 0 1 1 1.06 1.06l-3.25 3.25a.75.75 0 0 1-1.06 0L4.22 7.28a.75.75 0 0 1 0-1.06Z\" clip-rule=\"evenodd\" \/>\n            <\/svg><\/div><\/div><div class=\"field is-single has-term\" id=\"input-2\"><label for=\"field-2\">Object distance (d\u2092)<\/label><div class=\"term\">d\u2092<\/div>  <div class=\"absolute bottom-0 left-16 top-8 w-2 h-0.5 bg-blue-500\"><\/div><div class=\"field-group\"><input type=\"text\" name=\"object_distance_d\" id=\"field-2\" aria-describedby=\"calc-info-2\" data-number inputmode=\"decimal\" autocomplete=\"off\" spellcheck=\"false\" placeholder=\"e.g. 30\" min=\"0\" value=\"30\"\/><div class=\"grid grid-cols-1\"><select id=\"field-3\" name=\"unit\" aria-label=\"Unit\"><option value=\"mm\">mm<\/option><option value=\"cm\" selected>cm<\/option><option value=\"m\">m<\/option><option value=\"in\">in<\/option><option value=\"ft\">ft<\/option><\/select><svg class=\"pointer-events-none col-start-1 row-start-1 mr-2 size-5 self-center justify-self-end text-gray-500 sm:size-4\" viewBox=\"0 0 16 16\" fill=\"currentColor\" aria-hidden=\"true\" data-slot=\"icon\">\n              <path fill-rule=\"evenodd\" d=\"M4.22 6.22a.75.75 0 0 1 1.06 0L8 8.94l2.72-2.72a.75.75 0 1 1 1.06 1.06l-3.25 3.25a.75.75 0 0 1-1.06 0L4.22 7.28a.75.75 0 0 1 0-1.06Z\" clip-rule=\"evenodd\" \/>\n            <\/svg><\/div><\/div><small id=\"calc-info-2\">Distance from the object to the lens. Positive for a real object (the usual case).<\/small><\/div><div class=\"field is-single has-term\" id=\"input-3\" hidden><label for=\"field-4\">Image distance (d\u1d62)<\/label><div class=\"term\">d\u1d62<\/div>  <div class=\"absolute bottom-0 left-16 top-8 w-2 h-0.5 bg-blue-500\"><\/div><div class=\"field-group\"><input type=\"number\" name=\"image_distance_d\" id=\"field-4\" aria-describedby=\"calc-info-4\" placeholder=\"e.g. 15\" step=\"any\" value=\"15\"\/><div class=\"grid grid-cols-1\"><select id=\"field-5\" name=\"unit\" aria-label=\"Unit\"><option value=\"mm\">mm<\/option><option value=\"cm\" selected>cm<\/option><option value=\"m\">m<\/option><option value=\"in\">in<\/option><option value=\"ft\">ft<\/option><\/select><svg class=\"pointer-events-none col-start-1 row-start-1 mr-2 size-5 self-center justify-self-end text-gray-500 sm:size-4\" viewBox=\"0 0 16 16\" fill=\"currentColor\" aria-hidden=\"true\" data-slot=\"icon\">\n              <path fill-rule=\"evenodd\" d=\"M4.22 6.22a.75.75 0 0 1 1.06 0L8 8.94l2.72-2.72a.75.75 0 1 1 1.06 1.06l-3.25 3.25a.75.75 0 0 1-1.06 0L4.22 7.28a.75.75 0 0 1 0-1.06Z\" clip-rule=\"evenodd\" \/>\n            <\/svg><\/div><\/div><small id=\"calc-info-4\">Distance from the lens to the image. Positive for a real image, negative for a virtual image.<\/small><\/div><div class=\"field is-single has-term\" id=\"input-4\"><label for=\"field-6\">Focal length (f)<\/label><div class=\"term\">f<\/div>  <div class=\"absolute bottom-0 left-16 top-8 w-2 h-0.5 bg-blue-500\"><\/div><div class=\"field-group\"><input type=\"number\" name=\"focal_length_f\" id=\"field-6\" aria-describedby=\"calc-info-6\" placeholder=\"e.g. 10\" step=\"any\" value=\"10\"\/><div class=\"grid grid-cols-1\"><select id=\"field-7\" name=\"unit\" aria-label=\"Unit\"><option value=\"mm\">mm<\/option><option value=\"cm\" selected>cm<\/option><option value=\"m\">m<\/option><option value=\"in\">in<\/option><option value=\"ft\">ft<\/option><\/select><svg class=\"pointer-events-none col-start-1 row-start-1 mr-2 size-5 self-center justify-self-end text-gray-500 sm:size-4\" viewBox=\"0 0 16 16\" fill=\"currentColor\" aria-hidden=\"true\" data-slot=\"icon\">\n              <path fill-rule=\"evenodd\" d=\"M4.22 6.22a.75.75 0 0 1 1.06 0L8 8.94l2.72-2.72a.75.75 0 1 1 1.06 1.06l-3.25 3.25a.75.75 0 0 1-1.06 0L4.22 7.28a.75.75 0 0 1 0-1.06Z\" clip-rule=\"evenodd\" \/>\n            <\/svg><\/div><\/div><small id=\"calc-info-6\">Positive for a converging (convex) lens, negative for a diverging (concave) lens.<\/small><\/div><div class=\"field is-single has-term\" id=\"input-5\"><label for=\"field-8\">Object height (h\u2092) \u2014 optional<\/label><div class=\"term\">h\u2092<\/div>  <div class=\"absolute bottom-0 left-16 top-8 w-2 h-0.5 bg-blue-500\"><\/div><div class=\"field-group\"><input type=\"number\" name=\"object_height_h_optional\" id=\"field-8\" aria-describedby=\"calc-info-8\" placeholder=\"e.g. 5\" step=\"any\" value=\"5\"\/><div class=\"grid grid-cols-1\"><select id=\"field-9\" name=\"unit\" aria-label=\"Unit\"><option value=\"mm\">mm<\/option><option value=\"cm\" selected>cm<\/option><option value=\"m\">m<\/option><option value=\"in\">in<\/option><option value=\"ft\">ft<\/option><\/select><svg class=\"pointer-events-none col-start-1 row-start-1 mr-2 size-5 self-center justify-self-end text-gray-500 sm:size-4\" viewBox=\"0 0 16 16\" fill=\"currentColor\" aria-hidden=\"true\" data-slot=\"icon\">\n              <path fill-rule=\"evenodd\" d=\"M4.22 6.22a.75.75 0 0 1 1.06 0L8 8.94l2.72-2.72a.75.75 0 1 1 1.06 1.06l-3.25 3.25a.75.75 0 0 1-1.06 0L4.22 7.28a.75.75 0 0 1 0-1.06Z\" clip-rule=\"evenodd\" \/>\n            <\/svg><\/div><\/div><small id=\"calc-info-8\">Optional height of the object. Leave empty to calculate only the distances, image type and magnification.<\/small><\/div><\/fieldset><div class=\"buttons\"><button type=\"submit\" data-text=\"Re-Calculate\" id=\"calculate-button\" data-post=\"65885\">Calculate<\/button><button type=\"reset\">Reset<\/button><\/div><div class=\"field is-checkbox hidden!\" id=\"field-auto-calc\"><input type=\"checkbox\" id=\"auto-calc\"><label for=\"auto-calc\">Calculate automatically<\/label><small>If enabled, the result will update automatically when you change any value.<\/small><\/div><div class=\"fieldset-result is-hidden\" aria-labelledby=\"result-title\" aria-live=\"polite\" role=\"region\"> <h3 class=\"result-title bg-gradient-to-r from-primary-50 to-gray-50 dark:from-primary-900 dark:to-gray-800\" id=\"result-title\"><span class=\"icon icon-s-pulse\" aria-hidden=\"true\"><\/span> Thin Lens Results<\/h3><div class=\"result-box\"><div class=\"field-result is-column\" id=\"output-1\"><span class=\"field-title\"><span>Solved quantity and calculation steps<\/span><\/span><span class=\"field-value\" id=\"result-1\"><\/span><button type=\"button\" class=\"copy-result\" data-tooltip=\"Copy Result\" aria-label=\"Copy Result\"><span class=\"copy-icon icon icon-document-copy\" aria-hidden=\"true\"><\/span><\/button><\/div><div class=\"field-result is-column\" id=\"output-2\"><span class=\"field-title\"><span>Image type, magnification and image height<\/span><\/span><span class=\"field-value\" id=\"result-2\"><\/span><button type=\"button\" class=\"copy-result\" data-tooltip=\"Copy Result\" aria-label=\"Copy Result\"><span class=\"copy-icon icon icon-document-copy\" aria-hidden=\"true\"><\/span><\/button><\/div><\/div><div class=\"result-actions\"><button type=\"button\" class=\"copy-link\"><svg viewBox=\"0 0 20 20\" fill=\"currentColor\" aria-hidden=\"true\"><path d=\"M12.232 4.232a2.5 2.5 0 0 1 3.536 3.536l-1.225 1.224a.75.75 0 0 0 1.061 1.06l1.224-1.224a4 4 0 0 0-5.656-5.656l-3 3a4 4 0 0 0 .225 5.865.75.75 0 0 0 .977-1.138 2.5 2.5 0 0 1-.142-3.667l3-3Z\"\/><path d=\"M11.603 7.963a.75.75 0 0 0-.977 1.138 2.5 2.5 0 0 1 .142 3.667l-3 3a2.5 2.5 0 0 1-3.536-3.536l1.225-1.224a.75.75 0 0 0-1.061-1.06l-1.224 1.224a4 4 0 1 0 5.656 5.656l3-3a4 4 0 0 0-.225-5.865Z\"\/><\/svg><span class=\"copy-link__text\">Copy link to this calculation<\/span><\/button><span class=\"sr-only\" role=\"status\" id=\"copy-link-status\"><\/span><\/div><\/div><a href=\"#respond\" class=\"hidden transition-opacity duration-300 opacity-0 w-50 text-sm justify-center items-center gap-2 px-4 py-2 rounded bg-gray-200 text-gray-700 hover:bg-gray-300\" id=\"leave-comment\"><span class=\"icon icon-comments\" aria-hidden=\"true\"><\/span>Leave a Comment<\/a><\/form><\/section><section id=\"calc-reactions\" class=\"not-prose hidden my-12 bg-gradient-to-r from-primary-50 to-gray-50 border border-indigo-100 rounded-xl px-6 py-4 shadow-sm\" data-post=\"65885\" aria-live=\"polite\" aria-labelledby=\"calc-reactions-title\"><p id=\"calc-reactions-title\" class=\"text-sm text-gray-500 text-center mb-2\">How did this result make you feel?<\/p><div role=\"group\" aria-labelledby=\"calc-reactions-title\" class=\"grid grid-cols-3 sm:flex sm:flex-row sm:justify-around gap-4 sm:items-center sm:flex-wrap\"><button type=\"button\" aria-pressed=\"false\" class=\"reaction-btn flex flex-col items-center gap-1 text-sm text-gray-700 hover:text-primary-600 cursor-pointer transition-transform hover:scale-105\" data-reaction=\"like\"><span class=\"reaction-count\" data-reaction-count=\"like\">0<\/span><span class=\"reaction text-3xl\" aria-hidden=\"true\">\ud83d\ude00 <\/span><span class=\"reaction-description font-medium\">Like <\/span><\/button><button type=\"button\" aria-pressed=\"false\" class=\"reaction-btn flex flex-col items-center gap-1 text-sm text-gray-700 hover:text-primary-600 cursor-pointer transition-transform hover:scale-105\" data-reaction=\"helpful\"><span class=\"reaction-count\" data-reaction-count=\"helpful\">0<\/span><span class=\"reaction text-3xl\" aria-hidden=\"true\">\ud83d\udca1 <\/span><span class=\"reaction-description font-medium\">Helpful <\/span><\/button><button type=\"button\" aria-pressed=\"false\" class=\"reaction-btn flex flex-col items-center gap-1 text-sm text-gray-700 hover:text-primary-600 cursor-pointer transition-transform hover:scale-105\" data-reaction=\"confused\"><span class=\"reaction-count\" data-reaction-count=\"confused\">0<\/span><span class=\"reaction text-3xl\" aria-hidden=\"true\">\ud83d\ude15 <\/span><span class=\"reaction-description font-medium\">Confused <\/span><\/button><button type=\"button\" aria-pressed=\"false\" class=\"reaction-btn flex flex-col items-center gap-1 text-sm text-gray-700 hover:text-primary-600 cursor-pointer transition-transform hover:scale-105\" data-reaction=\"disappointed\"><span class=\"reaction-count\" data-reaction-count=\"disappointed\">0<\/span><span class=\"reaction text-3xl\" aria-hidden=\"true\">\ud83d\ude1e <\/span><span class=\"reaction-description font-medium\">Disappointed <\/span><\/button><button type=\"button\" aria-pressed=\"false\" class=\"reaction-btn flex flex-col items-center gap-1 text-sm text-gray-700 hover:text-primary-600 cursor-pointer transition-transform hover:scale-105\" data-reaction=\"inaccurate\"><span class=\"reaction-count\" data-reaction-count=\"inaccurate\">0<\/span><span class=\"reaction text-3xl\" aria-hidden=\"true\">\u274c <\/span><span class=\"reaction-description font-medium\">Inaccurate <\/span><\/button><\/div><div id=\"reaction-message\" class=\"hidden mt-8 rounded-md border border-primary-100 bg-white\/50 backdrop-blur-sm px-4 py-2 text-sm text-center shadow-sm\"><\/div><\/section><div class=\"calcdash-ad not-prose calcdash-ad--calc_result calcdash-ad--in-article\"><ins class=\"adsbygoogle\" style=\"display:block\" data-ad-client=\"ca-pub-1721569815777345\" data-ad-slot=\"6317458308\" data-ad-layout=\"in-article\" data-ad-format=\"fluid\"><\/ins><script>(adsbygoogle = window.adsbygoogle || []).push({});<\/script><\/div>\n<style id=\"wpcoderpro-inline-1\">.formula-box {\r\n\tborder-bottom: none !important;\r\n}<\/style><section class=\"formula-box\" aria-labelledby=\"formula-title\">\r\n\t<div id=\"formula-title\" class=\"not-prose font-display mb-4\"><span class=\"icon icon-formula\" aria-hidden=\"true\"><\/span><h2>Lens Equation Formula<\/h2><\/div>\r\n\t<figure class=\"not-prose formula\">\r\n\t\t<figcaption class=\"formula-title\">Formula<\/figcaption>\r\n\t\t<div class=\"text-base text-gray-800\" id=\"formula\">\\[ \\frac{1}{f} = \\frac{1}{d_o} + \\frac{1}{d_i} \\]<\/div>\r\n\t<\/figure>\r\n\t<\/p>\n<p><strong>Where:<\/strong><\/p>\n<ul>\n<li>\\(f\\) \u2014 focal length of the lens (m)<\/li>\n<li>\\(d_o\\) \u2014 object distance: from the object to the lens (m)<\/li>\n<li>\\(d_i\\) \u2014 image distance: from the lens to the image (m)<\/li>\n<\/ul>\n<p>Solving for the missing quantity gives three equivalent rearrangements: \\(d_i = \\dfrac{d_o f}{d_o - f}\\), \\(d_o = \\dfrac{d_i f}{d_i - f}\\) and \\(f = \\dfrac{d_o d_i}{d_o + d_i}\\). Once all three distances are known, the lateral magnification follows from \\(m = -\\dfrac{d_i}{d_o}\\), and the image height from \\(h_i = m\\,h_o\\).<\/p>\n<p>\r\n<\/section>\n<style id=\"wpcoderpro-inline-459\">.calculation-box {\r\n\tborder-bottom: none !important;\r\n}<\/style><section id=\"calculation\" class=\"calculation-box\" aria-labelledby=\"calculation-title\">\r\n\t<div id=\"calculation-title\" class=\"not-prose font-display\"><span class=\"icon icon-unordered-list\" aria-hidden=\"true\"><\/span><h2>Lens Equation \u2013 Calculation Example<\/h2><\/div>\r\n\r\n<\/p>\n<p><strong>Example:<\/strong> an object stands 30 cm in front of a converging lens with a focal length of 10 cm, and the object is 5 cm tall. Where does the image form, and what is it like?<\/p>\n<p>\\[ d_i = \\frac{d_o f}{d_o - f} = \\frac{0.30 \\times 0.10}{0.30 - 0.10} = \\frac{0.03}{0.20} = 0.15\\ \\text{m} \\]<\/p>\n<p>\\[ m = -\\frac{d_i}{d_o} = -\\frac{0.15}{0.30} = -0.5 \\]<\/p>\n<p>\\[ h_i = m\\,h_o = -0.5 \\times 0.05 = -0.025\\ \\text{m} \\]<\/p>\n<p><strong>Result:<\/strong> the image forms 15 cm behind the lens (real, since \\(d_i &gt; 0\\)). The magnification is \\(-0.5\\times\\), so the image is inverted and half the size of the object: 2.5 cm tall.<\/p>\n<p>\n\r\n<\/section>\n<h2>How to use the calculator<\/h2>\n<ol>\n<li>In the <strong>Solve for<\/strong> dropdown, choose the quantity you want to calculate: <em>Image distance (di)<\/em>, <em>Object distance (do)<\/em> or <em>Focal length (f)<\/em>. The field for that quantity is hidden \u2014 you enter the other two.<\/li>\n<li>Enter the two known distances in <strong>Object distance (do)<\/strong> and <strong>Focal length (f)<\/strong> (or <strong>Image distance (di)<\/strong> when solving for <em>do<\/em>), and pick the unit (mm, cm, m, in or ft) for each.<\/li>\n<li>Optionally enter the <strong>Object height (ho)<\/strong> if you also want the image height. Leave it empty to skip that part.<\/li>\n<li>Read the results: the solved distance (converted into metres, centimetres, millimetres, inches and feet), the lens type, whether the image is real or virtual, and the magnification, orientation and image height.<\/li>\n<\/ol>\n<h2>What the thin lens equation describes<\/h2>\n<p>The thin lens equation links the position of an object, the position of its image, and the focal length of a lens. A lens bends parallel rays so that they either converge to a point (a converging, or convex, lens with \\(f &gt; 0\\)) or appear to diverge from one (a diverging, or concave, lens with \\(f &lt; 0\\)). The focal length is the distance from the lens to that point, and it fully determines how the lens images objects \u2014 as long as the lens is thin compared with the distances involved.<\/p>\n<p>The sign convention matters. A real object in front of the lens has \\(d_o &gt; 0\\). A positive image distance means a <strong>real image<\/strong>: the light actually converges on the far side of the lens, so you can catch it on a screen or sensor \u2014 this is how cameras and projectors work. A negative image distance means a <strong>virtual image<\/strong>: the rays only appear to come from a point on the object's side of the lens, so you must look through the lens to see it, as with a magnifying glass or eyeglasses.<\/p>\n<p>The magnification \\(m = -d_i\/d_o\\) tells you how the image compares with the object. Its absolute value is the size ratio: \\(|m| = 2\\) means the image is twice as tall. The sign gives the orientation: a negative \\(m\\) means the image is inverted (upside down), a positive \\(m\\) means upright. Real images formed by a single converging lens are inverted; virtual ones are upright.<\/p>\n<p>Two special cases are worth remembering. If the object sits exactly at the focal point (\\(d_o = f\\)), the image forms at infinity \u2014 this is the setting of a searchlight or collimator. If the object is very far away (\\(d_o \\to \\infty\\)), then \\(d_i = f\\): parallel incoming rays focus at the focal point, which is how a camera focuses a distant scene onto the sensor.<\/p>\n<h2>Sign conventions at a glance<\/h2>\n<table>\n<thead>\n<tr>\n<th>Quantity<\/th>\n<th>Positive<\/th>\n<th>Negative<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>Focal length \\(f\\)<\/td>\n<td>Converging (convex) lens<\/td>\n<td>Diverging (concave) lens<\/td>\n<\/tr>\n<tr>\n<td>Object distance \\(d_o\\)<\/td>\n<td>Real object in front of the lens<\/td>\n<td>Virtual object (rare, e.g. in lens systems)<\/td>\n<\/tr>\n<tr>\n<td>Image distance \\(d_i\\)<\/td>\n<td>Real image behind the lens (projectable)<\/td>\n<td>Virtual image on the object's side<\/td>\n<\/tr>\n<tr>\n<td>Magnification \\(m\\)<\/td>\n<td>Upright image<\/td>\n<td>Inverted image<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<h2>Assumptions and limitations<\/h2>\n<ul>\n<li><strong>Thin lens:<\/strong> the lens thickness is assumed negligible compared with \\(d_o\\), \\(d_i\\) and \\(f\\). For thick lenses or lens systems, measured distances from principal planes give small corrections.<\/li>\n<li><strong>Paraxial rays:<\/strong> the equation holds for rays close to the optical axis and at small angles. Wide-aperture lenses suffer from aberrations that shift the true focus.<\/li>\n<li><strong>Single wavelength:<\/strong> the focal length depends slightly on the colour of the light (chromatic aberration), so the result is exact only for one wavelength.<\/li>\n<li>The calculator assumes the standard sign convention above. If your textbook uses a different convention, convert the signs before comparing results.<\/li>\n<li>Distances must be nonzero, and the degenerate cases (\\(d_o = f\\), \\(d_i = f\\), or \\(d_o = -d_i\\)) correspond to images or objects at infinity and are rejected with an explanation.<\/li>\n<\/ul>\n<h2>Related calculators<\/h2>\n<p>For more physics tools, try the <a href=\"https:\/\/wpcalc.com\/en\/physics\/kinematic-equations-solver\/\">Kinematic Equations Solver<\/a> for motion problems, the <a href=\"https:\/\/wpcalc.com\/en\/physics\/displacement-calculator\/\">Displacement Calculator<\/a> for position changes, or the <a href=\"https:\/\/wpcalc.com\/en\/physics\/power-calculator\/\">Power Calculator<\/a> for energy transfer over time.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Solve the thin lens equation 1\/f = 1\/do + 1\/di for image distance, object distance or focal length. Enter any two known values and get the third, plus image type, magnification and image height.<\/p>\n","protected":false},"author":3168,"featured_media":0,"comment_status":"open","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[62],"tags":[87],"class_list":["post-65885","post","type-post","status-publish","format-standard","hentry","category-physics","tag-waves-optics"],"acf":[],"_links":{"self":[{"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/posts\/65885","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/users\/3168"}],"replies":[{"embeddable":true,"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/comments?post=65885"}],"version-history":[{"count":1,"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/posts\/65885\/revisions"}],"predecessor-version":[{"id":65915,"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/posts\/65885\/revisions\/65915"}],"wp:attachment":[{"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/media?parent=65885"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/categories?post=65885"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/tags?post=65885"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}