http://www.google.com/imgres?imgurl=http://laserpointerforums.com/attachments/f42/11750-diy-homemade-laser-diode-driver-prototype_001.jpg&imgrefurl=http://laserpointerforums.com/f42/diy-homemade-laser-diode-driver-26339-19.html&usg=__lXjJJu23fUVkUTnMRu3Z_AOeWt0=&h=600&w=800&sz=146&hl=en&start=0&zoom=1&tbnid=I_wEeeyxKbzjiM:&tbnh=119&tbnw=158&ei=dzCGTfS4KYjKswaToaSTAw&prev=/images%3Fq%3Dlaser%2Bdiode%2Bdriver%26um%3D1%26hl%3Den%26sa%3DN%26biw%3D1024%26bih%3D677%26tbs%3Disch:1&um=1&itbs=1&iact=hc&vpx=279&vpy=72&dur=369&hovh=194&hovw=259&tx=177&ty=107&oei=dzCGTfS4KYjKswaToaSTAw&page=1&ndsp=20&ved=1t:429,r:1,s:0