Always perfectly oriented.

Semiflex 3D Ion Chamber

3D Thimble Ionization Chamber for Relative and
Absolute Dosimetry


Key Features

  • Vented, waterproof, fully guarded - the ideal chamber for relative and absolute dosimetry measurements in water, air or solid state phantoms
  • True 3D geometry - uniform response in any direction
  • Unique design - fast, accurate scanning in in-plane and cross-plane directions without tank rotation or change of detector setup
  • Easy horizontal or vertical mounting for high-resolution measurements in both radial and axial orientations
  • Reference-class ionization chamber with exceptional dosimetric characteristics - suitable for reference dosimetry following standard dosimetry protocols, e.g., IAEA TRS-398, AAPM TG-51
  • Small size (0.07 cm³), high spatial resolution - perfect for measurements in small and FFF fields down to a field size of 2.5 cm x 2.5 cm
  • Radioactive check device optionally available

The New Reference Class

Semiflex 3D meets and exceeds the performance requirements of a reference-class ionization chamber as laid out in AAPM TG-51 and IEC 60731:

  • Minimal polarity effect (< 0.4 % correction, < 0.5 % maximum variation)
  • Extremely low volume effect (est. ≤ 0.05 % correction in FFF field)
  • Excellent chamber settling (< 0.3 %)
  • Very low post-irradiation leakage - far below IEC 60731 requirements
  • Significantly reduced cable effects (< 100 fC / (Gy * cm))
  • Minimal chamber-to-chamber variation - reliable kQ and kS values
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3D geometry - uniform response in any direction
Designed for axial and radial profile measurements
Vertical chamber holder with stop thimble - quick, easy setup for scanning in axial orientation
Minimal volume averaging - ideal for absolute dose calibration in small fields of FF and FFF beams

Suitable for photon and electron dosimetry in multiple applications

  • LINAC Acceptance Testing
  • TPS Beam Data Commissioning
  • Clinical Reference Dosimetry
  • Point Dose Measurements

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