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TECHNOLOGIES FOR SENSORS AND CLINICAL INTRUMENTATION 22/06/2020 Microsoft Forms Exam 1. Complete the following table. Give at least 1 biomedical application (14 points) Sensor Conversion phenomenon (transduction principle) ex. Magneto- electric Excitation (Passive or active) Modulation (when pertinent) Ex. resistive Typical conditioning circuit Ex. Current- to-voltage Biomedical application/s Ex. Blood pressure measurement MEMs capacitive accelerometer Photocathode in the PMT Coulter counter Amorphous Selenium (a-Se) detector Photodiode (open circuit mode) Photodiode (photoconductive mode) Piezoelectric sensor pO2 sensor (Clark electrode) Silicon PN junction Temperature sensor Inert gas ionization chamber RTD ISFET LDR pCO2 sensor (Stow- Severinghaus electrode) 2. Consider the optical system shown in figure, used to measure the absorbance of a given sample at wavelength lambda2. A lightsource composed by different wavelengths is passed through a glass and an entrance slit. The glass and the slit works as monochromator. The glass has a refractive index that varies with wavelength as shown in figure. At which distance d the slit has to be positioned in order to measure absorbance at the wavelength lambda2? Justify answer by showing all the calculations. (4 points) 3. Consider the optical system of exercise 2. The photodiode has a response that is shown in figure. An absorbance A=1.5 is measured at the wavelength lambda2. What is the illuminance of the light source (in lux) if the output of the photodiode (open circuit mode) is 400mV? (Assume that the light attenuation in the overall system, apart from the absorbance in the sample, is equal to 30%) (5 points) 4. A proximity sensor is made by a variable capacitance Cx. The distance between the plates d(x) is a function of…