| 摘要 |
An apparatus for detecting modulated informations from emitted light turned around by an object is disclosed, in which a non-modulation interval is provided in a light signal from a transmitting side, an information from the transmitting side is received at a receiving side by its light receiving elements and the light signal from the transmitting side during the non-modulation interval is modulated and then reflected back to the transmitting side thereby transmitting a signal. Consequently, the space and the cost of the receiving side can be reduced, and the optical axes of the transmitting side and the receiving side can be positively adjusted with ease. Also, according to the present invention, a bar code is disclosed, which includes an optical recursive reflection member which reflects back a light incident thereon in substantially the same direction of the incident light. This bar code further includes a shutter which can modulate a code. |
