However, my 2nd hand CECHH had the same problem, so i followed this guide:
until the lens and servo block was accessible. I literally washed it so that lens, prism, laser- and photodiodes were soaked with this cleanser:
blowed it dry carefully 'by lungs' and left the drive in a warm place for 1h to let evaporate the cleanser. Drive worked perfectly again after re-assembly.
Hope that helps
Yes, that seems to be the lens. First thing drive-controller does after inserting a disk, is to try to focus the laser beam on the disk's reflective layer. The controller moves lens away from disk, switches on the laser and moves lense then towards the disk - until it focusses or hits the disk surface (that clicks). This procedure is done for the blue, red and infrared laser. Btw you should be able to visualize the infrared laser with your mobile cam.