Simple infrared detector

Although the human eye is unable to detect infrared light, this Kind of light is emitted by many apparatus around us in everyday life. In a number of cases it may be useful or interesting to be able to detect and prove the presence of infrared light. The present circuit is perfect for that purpose. It is based on a special integrated circuit which contains an IR irradiance to frequency converter. In other words, the converter's output frequency provides an indication of the measured light intensity. A very handy and simple circuit!