Color detecting sensor and method for ink ribbon

A color detecting sensor for an ink ribbon comprising:

• a first light emitting element for emitting red light;
• a second light emitting element for emitting green light;
• a third light emitting element for emitting blue light;,
• a light receiving element for receiving light emitted from each of the first, second and third light emitting elements through the ink ribbon;
• and
• detecting means for detecting a color of the ink ribbon forming at least a colorless and transparent portion and the colorless and transparent portion based on an output signal of the light receiving element, the detecting means including a storage section for storing, as color reference data, the output signal of the light receiving element when the first, second and third light emitting elements emit light through the colorless and transparent portion respectively, and a color deciding section for comparing, with the color reference data, the output signal of the light receiving element when the first, second and third light emitting elements emit light through the color formed on the ink ribbon respectively, thereby deciding the color of the ink ribbon.