The measurement list, SD.MeasList, is an
(currently
)
table of indices into the other fields in the
SD structure.
Because the optical properties in the
Medium structure are in the
same order as the wavelengths in SD.Lambda,
SD.MeasList(:,4) also serves as an indirect index into the
fields of the Medium
structure. If the corresponding field in the
SD structure is either an empty
list or not defined at all (e.g., because it is not appropriate for
the imager in question), a value of 0 should be used in the
measurement list to indicate that this parameter is not used. All other
columns must contain valid Matlab array indices.
The nine rows of SD.MeasList are indicies into the
following vector or matrix fields in the
SD structure:
SD.SrcPos
SD.DetPos
SD.ModFreq
SD.Lambda
Emission Wavelength (not implemented)
SD.TimeDelay
SD.TimeGateWidth
Correlation Time (not implemented)
SD.DataFormat (not implemented).
For matrix fields, the index is into the leading dimension. For
example, if SD.MeasList(5,2) is 3, then the
position of the detector (SD.MeasList(:,2)) used to make
measurement 5 is stored in SD.DetPos(3,:). Note
that the number of fields in the measurement list is not fixed;
additional fields will be added in the future as the need arises. The
order of the existing fields, however, is guaranteed not to
change.
Because SD.Lambda is used in fluorescence imaging to hold
both the excitation and emission wavelengths, both
SD.MeasList(:,4) and SD.MeasList(:,5) are
indices SD.Lambda and the two columns of the measurement
list indicate their function (in the context of the forward problem)
as well as the wavelength.
Similarly, SD.TimeDelay is used to hold both the delay
time between when the light enters the tissue and when the measurement
is made (SD.MeasList(:,6)) and the correlation between two
events separated in time (SD.MeasList(:,7)).
Normally, the measurement list is generated automatically, either
by readPMIData() (which
initializes the measurement list as it loads in experimental data) or
by genMeasList() (which
generates measurement lists for simulations).