Light Emitting Diodes (LEDs) have several strong attributes as a type of barcode scanners. LEDs are designed to be installed where space is at a premium. They operate at a short distance from the barcode. They have much longer life and are not affected by shock or vibration, as in the case in laser diodes. LEDs are available in several different wavelengths, in both the visible and infrared spectrum, making it possible to tailor the wavelength of the light source to the application.