American RSD spherical phantom

USARSD RS-1100A spherical phantom                                          

Overview

A reliable aid for demonstrating accuracy and system stabilityTools

RSD sphereMotifIt is a reliable auxiliary for checking mechanical and domestic treatment parameters. withTLD (or Thin Film Dosimetry) and TLD Dosimetry Cylinders. Also included are two spare nylon mounting rods and two spare blind nylon nuts. Optional: Truncated cone of ion chamber (includes molding or machining of ion chamber to user specifications at center of sphere) and film dosing cylinder.

When using the center of a sphere as a target for testing a treatment unit, it must indicate the relationship between the point of maximum dose and the target. For an accurate system, these should be closely aligned.

A three-dimensional dosimetry cylinder at the center of the sphere measures the deviation of the maximum dose from the target and the dose gradient along the three orthogonal axes of the sphere.The TLD dose measurement column is a stack of dry water dishes with a diameter of 44 mm. Seven of the discs have rings of concentric holes for TLD rods, 1 mm in diameter and 3 mm long. Disk #4 is located on the center plane of the cylinder. A smaller target disk is located in the center of this disk. It has a Hounsfield number of approximately 130 and is visible on CT scans. The disc is tightly assembled from two nylon rods and round blind nuts, which position the cylinder's linear and angular precision to the sphere and head.

Thin Film Dosing Cylinder: This is an optional cylinder that can be used withTLD cylinder interchange. It consists of 11 membrane trays and 12 dry water trays, using the same nylon assembly rods and blind nuts. A simple fixture is provided so that the user can tap the film disk from the film sheet.

Standard Cone: This is a dry water cone that fits exactly into the groove of the sphere. it accepts a dose measuring cylinder(TLD or film). It is located in the center of the cylinder of the ball.

Optional Cone: This is shaped to position the measurement volume of an ion chamber at the center of a sphere. This cone is custom-made to fit the customer's specific ion chamber.