Biomedical electronics and instruments, equipment, diagnostic & detection tools success based on the success of high sensitive biosensors invention and development. Biosensors are the active electronic, semiconductor electronics, optoelectronics or other technologies related devices which sense biological signal from membrane in the form of antibodies, antigens, bacteria''s, viruses, glucose, oxygen, pH etc called signal/stimuli/receptor at the contact of membrane and biosensor with transducer along with biological sensing element called ?ion-electron-interfacing? from where signal convert into detectable electrical signals through transduction principles and measured at computerized electronic signal processing system. This monograph strongly related only about optoelectronic biosensor, in which discussed investigated evanescent wave optical fiber biosensor is one of the strong light carry biological information sensation and high speed detection sensor. Book deal with review, research and fundamental modeling.