text: Standard CD/DVD readers can be used to read the assays. The CD/DVD readers contain a laser, set of optical elements which shape and focus the laser, a disk driver, and a signal detector that function as follows: 
  # The laser produces light of a selected wavelength. 
  # The beam of light hits the analyte in the spots of the microarrays and refracts. The mass of the analyte causes the angle of reflected light to be different from the angle of incident light. The reflective properties of the CD/DVD change based on the quantity of analyte in the sample.
  # The attenuated signal reaches the photodiode of the drive's pickup.
  # Analog signals are extracted, digitized, and converted to an image. 
  The signal or optical density of the image is inversely proportional to concentration.  The refractive index of light, which is directly proportional to concentration, can also be measured. A readable signal is only generated if the sample is at least 200 nm, otherwise it is too small to significantly disrupt reflection of incident laser light.
  DVD diagnostic software programs such as Kprobe, ODC, and PlexUtilities can also be used for testing arrays and assays prepared on DVDs. These programs rely on a basic DVD error correcting algorithm. DVDs are organized by sectors which each consist of 2064 bytes. A logical error correction code (ECC) block consists of 16 data sectors. The ECC block is the basic unit for testing disk quality by counting the number of parity inner errors (PIE) or parity inner failures (PIF). The software programs can analyze PIF density which is proportional to analyte concentration.