Oligo Arrays -Light-directed printing Synthetic linkers modified with photochemically removable protecting groups attached to substrate and direct light through a photolithographic mask to specific areas on the surface to produce localized photodeprotecti Chemical coupling occurs at those sites that were illuminated in the preceding step. Next, light is directed to different regions and cycle is epeated Current versions now exceed one million probes per array Please see Lipshutz, RJ, SP Fodor, TR Gingeras, and DJ Lockhart. " High Density Synthetic Oligonucleotide Arrays. " Nat Genet. 21, no. 1 Suppl (January 1999): 20-4Oligo Arrays I - Light-directed printing • Synthetic linkers modified with photochemically removable protecting groups attached to substrate and direct light through a photolithographic mask to specific areas on the surface to produce localized photodeprotection. • Chemical coupling occurs at those sites that were illuminated in the preceding step. Next, light is directed to different regions and cycle is repeated. • Current versions now exceed one million probes per array. Lipshutz, RJ, SP Fodor, TR Gingeras, and DJ Lockhart. "High Density Synthetic Oligonucleotide Arrays." Nat Genet. 21, no. 1 Suppl (January 1999): 20-4. Please See