IRcut-Pol-ND3 Filter

The new BelOptik IRcut-Pol-ND3 filter (utility patent DE202014008103U1) is a compact one-filter solution for variable light reduction on the Herschel wedge or solar prism for the white light solar observation. The filter is a linear polarizer, where the both classical laminated clear glass substrates are replaced with filter glasses. The filter is a 3 element filter and united the classical filter stack of OD3 neutral density filter and polarisation filter, expanded with a KG3 infrared cut filter. The beneficial is, reduce 4 to 6 glass-air surfaces down to 2 glass-air surfaces. This will minimized clearly reflexes, scattering light and wavefront distortions. The filter will screw in the eyepiece and turn around them, can be adjustable the image brightness. An additional IRcut filter for CCD astro cameras is not necessary.

Beloptik IRcut-Pol-ND3 filter
  • Schott glass KG3 & NG3
  • Polfilter linear
  • T~0,04% or OD3.4
  • Blocked IR up to 5000nm
  • Both sides AR coated
  • 1,25“ with thread M28,5 for 89,-EUR