{"product_id":"colenbrander-ruler","title":"Colenbrander Ruler","description":"\u003cp style=\"font-weight: 400;\"\u003e\u003cstrong\u003eThe COLENBRANDER DIOPTER RULER\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp style=\"font-weight: 400;\"\u003eThe ruler shows inches and centimeters. Most important, however, is the center scale, which shows DIOPTERS. Recording the reading distance in \u003cstrong\u003ediopters \u003c\/strong\u003e(the reciprocal of the distance in meters) greatly simplifies calculations and comparisons. It replaces the use of a visual acuity fraction\u003c\/p\u003e\n\u003cp style=\"font-weight: 400;\"\u003e\u003cstrong\u003e\u003cem\u003e(V = m \/ M = distance in meters \/ letter size) \u003c\/em\u003e\u003c\/strong\u003ewith a multiplication \u003cstrong\u003e\u003cem\u003e(1\/V = M.x.D = letter size x \u003c\/em\u003e\u003c\/strong\u003e\u003cstrong\u003e\u003cem\u003edistance in diopters)\u003c\/em\u003e\u003c\/strong\u003e.\u003c\/p\u003e\n\u003cp style=\"font-weight: 400;\"\u003eMeasuring the reading distance in diopters provides a simple check on the power of the reading add.\u003c\/p\u003e\n\u003cp style=\"font-weight: 400;\"\u003eThe \u003cstrong\u003ediamonds \u003c\/strong\u003eon the ruler represent steps that are equivalent to the print sample steps. For each diamond that the print is brought closer, the patient should be able to read one print size smaller, provided that the reading add is adjusted accordingly.\u003c\/p\u003e\n\u003cp style=\"font-weight: 400;\"\u003eThe short end of the ruler provides an \u003cstrong\u003eM-unit scale \u003c\/strong\u003eto measure the size of unknown print samples.\u003c\/p\u003e","brand":"Colenbrander","offers":[{"title":"Default Title","offer_id":45921511014561,"sku":"Colenbrander Ruler","price":13.75,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0718\/4321\/7569\/files\/Colenbrander_Diopter_Ruler_Front.jpg?v=1776157235","url":"https:\/\/precision-vision.com\/products\/colenbrander-ruler","provider":"Precision Vision","version":"1.0","type":"link"}