PORTABLE TELEPHONE SET, ITS CASING AND CALL DISPLAY DEVICE FOR PORTABLE TELEPHONE SET

摘要

PROBLEM TO BE SOLVED: To provide various incoming displays of a portable telephone set and to improve visibility in darkness. SOLUTION: A casing 2 for a portable telephone set 1 or incoming display device 10 is applied with a coating to emit light by black light radiation, a coating to change its color by ultraviolet radiation or a phosphorescent coating, or pigments are mixed into constitutive materials of the casing, and inside the casing, a black light radiating element or ultraviolet radiating element is provided to be operated at the time of call incoming.