There is provided an azeotropic mixture having 1,1,1,3,3-pentafluoropropane and hydrogen fluoride. The backlight module includes: a backplane, a light guide plate arranged in the backplane, a backlight source arranged in the backplane, an optic film assembly arranged above the light guide plate, and a reflection plate arranged between the backplane and the light guide plate. A feature vector is assembled based on the algorithmically extracted data and rendered accessible to character recognition apparatus. If there is no work to perform, the power management control may delay powering the processor up until there is work to perform, saving additional power.