Pharmaceutical preparation methods and systems using imaging technologies

A system for determining a presence of fluid or air in a non-opaque tube in a pharmaceutical preparation device, the system comprising:

• a processing circuitry (PC), the PC being configured to:
• a) receive a camera image of the non-opaque tube, the non-opaque tube being positioned, from a camera perspective, in front of a patterned backdrop separate from and outside of the non-opaque tube, and comprising a region of parallel diagonal lines extending in parallel along a direction diagonal to a longitudinal axis along which the non-opaque tube extends,
• the received camera image thereby depicting one or more depicted regions of the non-opaque tube, wherein each depicted region is associated with a respective degree of refraction of the patterned backdrop according with refraction apparent in the camera image of a respective depicted portion of the patterned backdrop behind said depicted region and wherein the one or more depicted regions include at least one bubble or air gap;
• b) identify, using image processing techniques, in the received camera image, one or more of the depicted regions of the non-opaque tube;
• and
• c) determine a content characteristic of the non-opaque tube, based on imaged refractions of the patterned backdrop resulting from the respective degree of refraction associated with each said identified depicted region of the non-opaque tube.