Transducers are devices used for capturing and outputing chunks of data. Definition of ‘transducer’ encompasses the entire set analog and digital devices like photo or video camers, TV sets, radios, microphones, Xerox and, even scanners. However, a simple DIY cardboard apparatus over here demonstrates how to transform your cellphone into a document scanner — by clicking images of the document from a proper distance! Seems to be have been developed by some smart geek. Digital scanners, however, fundamentally differ from the principle shown out here; they use ‘light split’ technology that alters the colors of light as it passes through paper and text portions of the document, finally to create a digital stream of 0s and 1s. This apparatus needs to be credited for providing exactly similar functionality without any apparent disadvantage so no harm in trying it out. Check out for more pics.
Source: walyou