There is provided a semiconductor integrated circuit for an optical sensor for receiving environmental light through a cover member that attenuates visible light and transmits infrared light and a collecting lens, performing luminosity factor correction based on an amount of received light, and detecting an illuminance, wherein the semiconductor integrated circuit includes a first light receiving element having a first spectral property; a second light receiving element having a second spectral property; and a luminosity factor correction unit configured to perform the luminosity factor correction according to output of the first light receiving element and output of the second light receiving element, wherein the luminosity factor correction unit includes an AD conversion unit performed by time division on the output of the first light receiving element and the output of the second light receiving element, and a calculating unit subtracting digital signals obtained by the conversion.