P09052: Molecular Imaging System Upgrade

Prototype Calibration

Prototype Calibration

May 6th, 2009

Using an image distance of ~25 cm, an image distance of ~3 cm, and an projection angle of 30 degrees down from the platen, both fine and coarse calibration were performed in the finished prototype. 10 transparencies were used as a target.

Information on the procedure and previous results outside of the prototype can be be found here:


Camera Settings

public/Camera Settings.bmp

Coarse Calibration

The phase versus voltage plot from coarse calibration can be seen below and yielded center voltages of 48.45 V and 74.22 V.


Fine Calibration

75 images were taken during fine calibration in 1 V increments above and below the center voltages. A calibration key for what voltages were used for imaging can be found at the link below.


The resulting spectra from the six line average and the single line can be seen below.

Single Line Spectrum


Average Spectrum


The resulting merit maps for the single and six line average can be seen below.



The lowest score for the single line spectrum was 30.8 and 29.6 for the six line average. Both of these occurred at the voltages 48.45 V and 74.22 V. The individual images and Optigrid image for this combination can be seen below and can also be downloaded in raw TIF form at the links below the images.

20 V Image


20 V image

48.45 V Image


48.45 V image

74.22 V Image


74.22 V image

Combined Optigrid Image


Raw OG image