A method of scanning and reading indicia off a display is disclosed. The method may utilize a light sensor of a mobile device to improve the quality of reading indicia, such as a barcode, off a display. A scanner illuminates the mobile device in order to increase the backlight intensity and obtain a high contrast image on the display and then ceases illumination in order to scan the high contrast image without specular reflection caused by the scanner illumination. In one embodiment, the scanner illuminates the mobile device for a period of time to achieve the maximum level of brightness that the mobile device is capable of emitting on the display in the period of time before ceasing the illumination. In another embodiment, the scanner detects whether the change in brightness is greater than predefined level before ceasing the illumination.