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PalmOS PDA Applications: Gap

Gap Calculator is an application for PalmOS handheld computers which calculates the skin gap between two adjacent (and diverging) radiotherapy fields matched at depth for dose uniformity. This calculator solves the following equation:

Gap = ((0.5 * L1 * d1) / SSD1) + ((0.5 * L2 * d2) / SSD2).


SSD1,SSD2 = Source-Skin-Distance (SSD) for fields 1 & 2.
L1,L2 = Length of fields 1 & 2.
d1,d2 = Match depth for fields 1 & 2.

Click here to download the self extracting archive: Gap Calculator 1.0.5 (60K), last updated 9/8/03.

Download: GapCalc.prc.zip (16K)

To use, simply fill in the SSD, L and d fields, or use the bumper buttons to change the values. The gap is recalculated automatically any time the bumpers are used to make changes. If you manually enter data in the text fields, make all necessary changes and then click the "Calculate Gap" button to update the display. Below are some screen captures of the calculator running under the PalmOS 5.2.1 simulator:

Fig 1
Fig 2
Fig 3

Return to: Palm Programs