These single element (Best Form Shape) singlets are designed to yield a minimum spot size using 632.8nm light. They will also work well for most visible diodes up to 670nm (focusing only). The coating (¼ wave MgF2) is optimized for 632.8nm to provide maximum transmission. Dopt was designed to accommodate 99% of the 1/e2 beam profile of the most commonly available HeNe lasers. Each element is pitch polished to minimize scratch/dig defects and to provide low surface scattering. All dimensions are in mm.