1.0Crystalfontz LCD Bloghttps://www.crystalfontz.com/blogrich600338<blockquote class="wp-embedded-content" data-secret="nZCzskdYih"><a href="https://www.crystalfontz.com/blog/glossary/backlight/">Backlight</a></blockquote><iframe sandbox="allow-scripts" security="restricted" src="https://www.crystalfontz.com/blog/glossary/backlight/embed/#?secret=nZCzskdYih" width="600" height="338" title="“Backlight” — Crystalfontz LCD Blog" data-secret="nZCzskdYih" frameborder="0" marginwidth="0" marginheight="0" scrolling="no" class="wp-embedded-content"></iframe><script> /*! This file is auto-generated */ !function(d,l){"use strict";l.querySelector&&d.addEventListener&&"undefined"!=typeof URL&&(d.wp=d.wp||{},d.wp.receiveEmbedMessage||(d.wp.receiveEmbedMessage=function(e){var t=e.data;if((t||t.secret||t.message||t.value)&&!/[^a-zA-Z0-9]/.test(t.secret)){for(var s,r,n,a=l.querySelectorAll('iframe[data-secret="'+t.secret+'"]'),o=l.querySelectorAll('blockquote[data-secret="'+t.secret+'"]'),c=new RegExp("^https?:$","i"),i=0;i<o.length;i++)o[i].style.display="none";for(i=0;i<a.length;i++)s=a[i],e.source===s.contentWindow&&(s.removeAttribute("style"),"height"===t.message?(1e3<(r=parseInt(t.value,10))?r=1e3:~~r<200&&(r=200),s.height=r):"link"===t.message&&(r=new URL(s.getAttribute("src")),n=new URL(t.value),c.test(n.protocol))&&n.host===r.host&&l.activeElement===s&&(d.top.location.href=t.value))}},d.addEventListener("message",d.wp.receiveEmbedMessage,!1),l.addEventListener("DOMContentLoaded",function(){for(var e,t,s=l.querySelectorAll("iframe.wp-embedded-content"),r=0;r<s.length;r++)(t=(e=s[r]).getAttribute("data-secret"))||(t=Math.random().toString(36).substring(2,12),e.src+="#?secret="+t,e.setAttribute("data-secret",t)),e.contentWindow.postMessage({message:"ready",secret:t},"*")},!1)))}(window,document); //# sourceURL=https://www.crystalfontz.com/blog/wp-includes/js/wp-embed.min.js </script> A backlight is used behind the LCD glass to allow the LCM to be read in dark conditions. The vast majority of backlights are now LED. Historically there were also EL (electroluminescent) and CCFL (Cold Cathode Fluorescent Light) backlights, but as LED efficiency has increased and cost has decreased, EL and CCFL backlights have all but disappeared.https://www.crystalfontz.com/blog/wp-content/uploads/Array_LED_Backlight.jpg800532