Mitutoyo M Plan Apo NIR 20x Objective (NA 0.40, WD 20mm, 480–1800nm, M26)

The Mitutoyo M Plan Apo NIR 20× is a wide-area survey and inspection objective from Mitutoyo’s M Plan Apo NIR series — combining plan apochromat correction, a 20mm working distance, and an extraordinary 480–1800nm spectral range that extends well into the short-wave infrared (SWIR). The 20mm working distance is exceptional for a 20× objective, providing clearance for the full range of semiconductor inspection fixtures, environmental chambers, cryostats, vacuum systems, and laser processing setups, as well as ample room for beam delivery optics and collection systems that must coexist with the imaging objective. The 1800nm upper wavelength limit enables applications that require SWIR transmission including InGaAs camera imaging, SWIR fluorescence imaging, and Raman spectroscopy with long-wavelength excitation lasers (1064nm, 1550nm). For silicon wafer inspection, the extended SWIR range enables through-silicon imaging at wavelengths where silicon is highly transparent, enabling backside inspection, subsurface defect detection, and wide-area survey of large wafer surfaces at 20× before stepping up to higher magnification for detailed inspection. At 20× with a 1.2mm field of view (with Ø24 eyepiece), this objective provides a practical balance between field of view and resolution for wide-area NIR/SWIR survey and navigation. The plan apochromat correction ensures flat-field imaging with accurate chromatic registration across the full 480–1800nm spectral range. Compatible with Mitutoyo FS series microscopes and other infinity-corrected systems with M26 thread nosepieces. Catalog number 378-824-16.