Lens Characterization for Multifocus Microscopy Applications
Engineering
Bioengineering Senior Thesis Project
In this study, a lens characterization system was constructed in order to compare the light efficiency and aberration robustness of an achromatic doublet lens to a camera lens in order to determine their effectiveness as the secondary relay lens in a Multifocus Microscopy (MFM) imaging system. To do this, a custom microscope was constructed with a 50/50 beamsplitter to allow for Point Spread Functions to be recorded on two different cameras using the two different lenses simultaneously. These Point Spread Functions allowed for aberration to be observed and intensity profile plots at the in-focus plane to be fit to Gaussian distributions to calculate experimental resolution and light efficiency. After characterizing the aligned system, the camera lens and achromatic doublet lens were misaligned laterally by the same amount before recording more PSFs allowing for characterization of the outer local regions of the lenses. After completing this project, I concluded that while the achromatic doublet lens did appear to be more light efficient than the camera lens, misalignment of 10mm laterally caused the light efficiency of the achromatic doublet to approach that of the camera lens. Also at 10mm misalignment, there is evidence that the achromatic doublet arm's resolution began to worsen. These findings imply that the outer regions of the camera lens are more consistent for maintaining light efficiency and resolution when compared to the center region than the achromatic doublet's.
