Matching Pairs Optical ToolsOnline version Tools found in an optical. by Liliana Mejia Rodriguez 1 Lensometer: Measures lens prescription. 2 Hot Fingers: Hold metal and heats it to be inserted in plastic/zyl. Can be used to replace hinges or add guard arms to plastic/zyl frames. 3 Progressive Layout Chart 4 Hidden Circle Finding Instrument: Magnifier with light to enlarge the engraved symbols. 5 Distometer: Measures the distance between the apex of the cornea and the back of the lens. 6 Frame Warmer: Salt pan: Heats zyl or plastic frames for adjustment. 7 Bionic Thumb: Helps to create temple bends or to brace for screw replacements. 8 Frame Warmer: Hot Air Blowers: Heats zyl or plastic frames for adjustment. 9 Drill or Dremel Drill: Removes stuck screws or makes holes in lenses (rimless glasses). 10 Screw Extractor/Punch: Used to remove stuck screws or when the screw head is stripped or broken off.