An electronic device according to various embodiments of the present invention comprises: an infrared filter for passing light in an infrared wavelength band; an image sensor for converting the received light into a video signal and outputting the video signal; an infrared light-emitting unit for emitting the light in the infrared wavelength band; and a processor. The processor can execute a first application, confirm a security level of the first application, and authorize the first application with an authority for controlling at least one of the image sensor, the infrared filter and the infrared light-emitting unit according to the confirmed security level of the first application.

An electronic bead string includes a main bead, a plurality of secondary beads, a displacement sensor, a memory, and a processor. The main bead and the secondary beads are strung together to form a bead string. The displacement sensor is fixed in the main bead to output two-dimensional displacement signals, the memory stores the two-dimensional displacement signals, and the processor determines whether a rotation cycle of the electronic bead string is an approved rotation cycle according to the two-dimensional displacement signals.

An electronic bead string includes a main bead, a plurality of secondary beads, a displacement sensor, a memory, and a processor. The main bead and the secondary beads are strung together to form a bead string. The displacement sensor is fixed in the main bead to output two-dimensional displacement signals, the memory stores the two-dimensional displacement signals, and the processor determines whether a rotation cycle of the electronic bead string is an approved rotation cycle according to the two-dimensional displacement signals.

An electronic bead string includes a main bead, a plurality of secondary beads, a displacement sensor, a memory, and a processor. The main bead and the secondary beads are strung together to form a bead string. The displacement sensor is fixed in the main bead to output two-dimensional displacement signals, the memory stores the two-dimensional displacement signals, and the processor determines whether a rotation cycle of the electronic bead string is an approved rotation cycle according to the two-dimensional displacement signals.