When I encounter a transparent object that I need to view with a microscope, I often use dark field.  This is a 'DC stop' that blocks like coming directly back from the object and only allows rays of NA > 0 to pass.  It highlights the edges of a transparent (phase) object.

I want to perform a similar image simulation using OpticStudio.

I cannot find any ready-to-use analyses for phase objects.  Is there a geometric Image Analysis that allows the object to be phase rather than an absorbing object?

Seems that I can do a simple simulation 'by hand' by using the MTF from an obscured optical system or the PSF from the same and convolving that with the object.