A portable electronic device includes an infrared touch screen and a processor. The infrared touch screen includes a detection unit, a filter unit, and a signal conversion unit. The detection unit detects the intensity of the infrared beams reflected by a users body part placed on the infrared touch screen, and converts the detected intensity of the infrared beam to electrical signals. The filter unit filters the electrical signals and amplifies the filtered electrical signals. The signal conversion unit converts the electrical signals to digital signals. The processor includes an information processing module and a display control module. The information processing module processes the digital signals to obtain the heart rate information of the user, and creates a heart rate monitoring result according to the heart rate information of the user. The display control module controls the infrared touch screen to display the heart rate monitoring result.
