| 摘要 |
PROBLEM TO BE SOLVED: To judge between true and false objects, e.g. various kinds of cartridge, being used in an information apparatus, e.g. various types of printer, such that the judging method is not analyzed easily without complicating the structure of the information apparatus or the shape of the object itself. SOLUTION: A reflector exhibiting different reflectances for a plurality of wavelength are pasted to an object to be detected, e.g. an ink ribbon cartridge. The reflector is irradiated with light of a plurality of wavelengths from a light emitting section (S1, S6) and a decision is made whether a specified quantity of reflected light is received or not at a light receiving section for each wavelength (S4, S8) thus judging between true and false objects. |
