Differential Interference Contrast (DIC)

Prerequisites for DIC observation / recording

1.Koehler alignment of illumination path (transmitted light mode)

• If objective iris aperture is present: check if open)
• Focus a sample in transmitted light mode
• Close field aperture of illumination (first aperture after lamp)
• Focus field aperture (sharp contrast)
• Center field aperture
• Open field aperture (until aperture is no more visible)

2. DIC alignment

• Remove both DIC prisms from the illumination path
• Insert polarizer and analyzer into the illumination path
• Rotate polarizer or analyzer to minimize brightness
• Insert appropriate objective and condenser DIC prisms
• Adjust the condenser aperture roughly to the objective's aperture