Baader UBVRI Photometric B-Filter 50x50mm (4mm Glass) with Low Profile Filter Cell (LPFC)
- 50x50 mm Baader UBVRI - B-Filter
- Photometric Johnson/Bessel filter system
- partial dielectric design with BBAR minimized reflections
- Planeoptically polished, 4mm glass thickness
- non-ageing sealed coating edges
Baader UBVRI Filters - Specifications
Baader 4 mm thick UBVRI filters feature a proprietory design that strictly adheres to the classic Johnson/Bessel transmission specification. Unlike the classic construction that regularly has a thickness of 5mm or more, the Baader-filters are made of dielectric layers as well as absorption glasses. This allows for a smaller filter thickness of 4 mm. The original stack of pure colored glass had a thickness of 5 or 6 mm and would be too thick and too heavy for modern filter wheels.
In the old days UBVIR-filters were used for photodetectors and no one would care if the huge stack of cemented absorption glasses would cause havoc in terms of inherent internal reflections. Our method of combining dielectric coatings with a combination of short pass and long pass filters does provide for perfect off-band blocking into the far ends of the spectrum. This steep off-band-blocking would not be possible with pure dielectric layers over such a large transmission range.
MANUFACTURER Baader Planetarium SKU (#) 2459444B WEIGHT (NETTO) 0.026 COLOUR Black TRANSMISSION RANGE Transmission range after Johnson/Bessel FILTER THICKNESS (WITHOUT CELL) 4 mm CWL (CENTRAL WAVELENGTH) Bessel B AR-COATING dielectrically coated, planeoptically polished FILTER SIZE 50 x 50 mm FILTER USAGE Specialty, UBVRI FILTER MOUNTED Unmounted TYPE OF FILTER Bandpass SINGLE OR SET? Single Filter FILTER SHAPE square
Delivery Weight Package