Sequential steps in the development of the final version of the magnivisualizer
| Prototype with year | Light source | Magnification | Main body | Deficiency observed | Improvement |
|---|---|---|---|---|---|
| First prototype (1997) | Halogen bulb of 50 watt | 2.5 dioptre single lens | Stainless steel body with a simple PVC handle for wiring | Weak light intensity and low magnification Heating of light chamber | – |
| Second prototype (2000) | Halogen bulb of 100 Watt | 5 dioptre single lens | Stainless steel body with a simple PVC handle | Heating of light chamber Irregular shadow rings Fixed single magnification | Intensity of light improved for visualising the cervix |
| Third prototype (2004) | Halogen bulb of 100 watt with mercury reflector | Interchangeable lenses of 1, 2 and 3 dioptre values | Aluminium body drilled with some holes in the chamber for heat shield. PVC handle | Lack of a better grip Lack of a switching mechanism Lack of a coherent beam | Further improvement in the intensity of light for visualising the cervix Provides the choice of magnification for the users from ×2 to ×5 Overheating of the light chamber was prevented |
| Commercial model (2009) | Halogen bulb of 100 watt with mercury reflector 80-B Kodak filter with diffuser lenses were attached Die-cast PVC grip with a miniature switch, which could be operated with the right hand thumb | Interchangeable lenses of 1, 2 and 3 dioptre values | Aluminium body drilled with some more big size holes in the chamber for heat shield. PVC handle | None | The light was improved as a balanced white light (complete spectrum of light) This model was user-friendly, well accepted by the users and was validated This was the final commercial version of the instrument launched by ICMR |
ICMR, Institute of Cytology and Preventive Oncology.