Figure 1: OPTM image collection set-up. The specimen is packed inside a micro-capillary tube and suspended in gel with index of refraction identical to that of the capillary tube. This eliminates optical refraction by the capillary tube. The capillary is embedded in a cartridge (not shown) with cover slips above and under it, also embedded in the same gel. The cartridge is placed on a stage, which can shifted laterally by a motor. The capillary is rotated by another motor for different perspectives to be imaged. Piezoelectric positioner (PZT) moves the objective axially in order to axially to scan the specimen; this extends the depth of field of the objective.