A method for measuring blood glucose levels by a portable terminal using a strip module is provided. The strip module includes a dye pad having a color that changes in response to a sample applied to the dye pad. The strip module also includes a transparent strip having a first side and a second side. The first side is opposite the second side. The dye pad is mounted on the first side of the transparent strip, and the transparent strip reflects light provided from a light source of a portable terminal located adjacent to the second side and transmits the light to the dye pad.