Fiber-OpticDosimeter

Orbital Therapy’s HRD-6 High Resolution Fiber Optic Dosimeter is the first in a new class of radiation dosimeters with unprecedented spatial resolution and sensitivity. This instrument is designed specifically for measuring the dose distribution around low energy x-ray emitting brachytherapy sources. The detector is a 0.5mm long in diameter cylindrical plastic scintillator coupled to a fiber optic cable. All of the materials used in the construction of the detector are near water equivalent for reduced radiation field perturbation. The detector is waterproof for use in water phantoms to measure absorbed dose to water directly in liquid water. The high sensitivity permits direct measurement of low activity sources for the first time.

The dosimeter instrument has status indicators on the front panel as well as the fiber optic connector for the detector assembly. Normal operation of the dosimeter system is done through supplied software running on a windows based PC. A USB interface from the dosimeter to the PC handles all control and data acquisition communications.

The detector assembly consists of an extremely small plastic scintillator coupled to a fiber optic cable covered by a light-tight housing. The scintillator is 0.5mm diameter and 0.5mm long. The detector is waterproof for making measurements of absorbed dose around brachytherapy sources in water.

The detector assembly is available in a number of sizes, including a low profile detector measuring 2.2 mm in diameter.

Fiber Optic Scintillator Measured Depth Dose vs. TG43 Consensus Data, 125I 6/3/04

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Fiber Optic Scintillator TG43

User controlled software for time integration and dark

count subtraction.

Detector specifications:Active volume: 0.5mm diameter x 0.5mm thick

Cable length: 1 meter (39.4 inches) – custom sizes available upon request

Instrument specifications:Sensitivity: 100 microGray in 10 seconds to 10% with 0.5mm detector with 30kV x-rays

Optical shutter: Included for automatic dark count subtraction

Dynamic range: Greater than 106

Temperature range: 15-35C

Relative humidity 10-80%

Computer Interface: USB

Size: 10 x 10 x 4 inches (250 x 250 x 100mm)

Weight: 4 pounds (2kg)

Power: USB

Supplied software:LabView based user interface for controlling all dosimeter functions:

Integration time, dark count subtraction, spreadsheet compatible data file

Orbital Therapy LLC8 Alfred Circle

Bedford, MA 01730

508-202-7224 tel508-371-3434 fax

www.orbitaltherapy.com

Copyright © 2009 Orbital Therapy LLC 3-3 rev B