Reflective Microscope Objectives
  • Wide spectral band
  • Long working distances
  • High numerical apertures
  • Zero chromatic aberration
  • Negligible coma, spherical, and astigmatic aberrations

Product Description

Newport's Reflective Microscope Objectives are reverse Cassegrains following the Schwarzchild design. Accordingly, they have zero chromatic aberration, and negligible coma, spherical, and astigmatic aberrations. We offer 15X and 36X objectives, broadband coated with aluminum and over-coated with magnesium fluoride (MgF2). They are usable from 200nm to 20mm. Special coatings are available upon request including Gold for the visible to IR region.

How They Work

In a typical focusing application, collimated light passes through the aperture hole in the primary mirror to the secondary mirror. The secondary mirror reflects and diverges the beam to fill the primary mirror. The primary mirror focuses the beam to a small spot called the Object Plane or Focal Point. Some common applications include UV Metrology and Microscopy, Spatial Filtering, Photo-microscopy, Laser Energy Delivery Systems, and FT-IR Spectroscopy.

To discuss your specific requirements, please call 508-528-4411 to speak directly to one of our Technical Sales Engineers, or email us at

Ordering Information

50105-01Reflective Microscope Objective, 15x, 160mm BFL
50105-02Reflective Microscope Objective, 15x, Infinite BFL
50102-01Reflective Microscope Objective, 36x, 160mm BFL
50102-02Reflective Microscope Objective, 36x, Infinite BFL

Item Specifications
ModelMagnificationNumerical ApertureBFL (mm)Working Distance (mm)Field of View (mm)Focal Length (mm)Obscuration (%)Secondary Mirror Diameter (mm)
50105-0215x0.4 241.2132710.5

Dimensions [in. (mm)]
50105-011.94 (49.3)N/A1.52 (38.6)0.94 (24.0)12.0°23.6°6.30 (160.0)
50105-021.94 (49.3)0.383 (9.72)1.52 (38.6)0.94 (24.0)12.0°23.6°N/A
50102-011.94 (49.3)N/A1.52 (38.6)0.41 (10.4)15.0°30°6.30 (160.0)
50102-021.94 (49.3)0.212 (5.3)1.52 (38.6)0.41 (10.4)15.0°30°N/A

Typical reflectance curves of metallic reflective coatings

Dimensional diagram of Newport Infinite BFL Reflective Microscope Objective

Dimensional diagram of Newport 160 mm BFL Reflective Microscope Objective

A) Diagram of a typical focusing application of a reflective microscope objective
B) Illustration of the rear focal plane of a 160 mm back focal length objective