A device for detecting analytes in a sample includes (a) n light source units generating light; (b) a reaction strip including (i) a test area illuminated with light from the light source unit and including a material reacting to the analytes, (ii) a control area illuminated with the light from the light source unit and including a control material, and (iii) a background area illuminated with the light from the light source unit; and (c) at least n+1 light receiving units detecting light emitted from the test area, the control area, and the background area of the reaction strip, respectively.