What are the wavelength and type of the laser used in a standard CD-ROM drive?

Correct option is B

Correct Answer: B) 780 nm; infrared laser

Explanation:

• A standard CD-ROM drive uses a laser with a wavelength of 780 nanometers, which falls in the infrared region of the electromagnetic spectrum.
• This infrared laser is used to read data encoded in the reflective layer of the CD by detecting the changes in reflection caused by pits and lands on the disc surface.

Information Booster:

• DVD drives typically use a 650 nm red laser for higher precision and storage density.
• Blu-ray discs use a 405 nm blue-violet laser, allowing even finer resolution for higher capacity.
• The choice of laser wavelength directly influences the storage capacity and precision of the optical drive.