The Analysis of The Optical Measurement Sensitivity of The Phototransistor and LDR Sensors

Mehmet Ali Özçelik


The light sensitive circuit elements, in line with the changes in the amount of light, produce electrical values such as current, voltage and resistance change. Thus, these elements are being used in light measurement, light control and light detection systems. In this research, the Phototransistor and LDR (light dependent resistor), which are commonly used in light detection systems, have been exposed to different lighting values in an indoor environment. Their electrical reaction values have been measured and sensitivity analysis has been conducted. In the light of the findings obtained, it has been seen that with 134.23 standard deviation rate Phototransistor has shown more light sensitivity than LDR.


LDR sensor, Phototransistor, Light intensity, Lux-meter, Photo-current.

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