Question

Lasers are used to burn and read CDs. Explain why a laser that emits blue light would be capable of burning and reading more information than one that emits infrared.

a) Blue light has higher energy, allowing for more precise burning.

b) Infrared light is more focused, providing better resolution.

c) The color of the laser does not affect burning or reading capabilities.

d) Infrared light is absorbed more efficiently by CD surfaces.

Answer 1

A blue light laser can burn and read more information on a CD than an infrared laser due to the shorter wavelength of blue light, which allows for higher precision and data density.

Step-by-step explanation:

Lasers are crucial for both burning and reading CDs. The capability of a laser to store and retrieve information efficiently from a CD depends on the laser's wavelength. Blue light lasers have a shorter wavelength compared to infrared lasers, which translates into higher precision when burning and reading the disc. Specifically, the shorter wavelength of blue light (around 405 nm) allows for the creation and detection of smaller pits on the disc's surface, which means data can be packed more densely, increasing the amount of information that can be stored and read. This principle is employed by Blu-Ray players, which use blue lasers to read the significantly smaller pits that represent data on a Blu-Ray disc.

The correct answer to the question is thus a) Blue light has higher energy, allowing for more precise burning. Infrared light, on the other hand, has longer wavelengths, which result in larger focal spots and lower resolution, making it less efficient for storing and reading high-density digital information on optical media like CDs and Blu-Rays.