| 摘要 |
PROBLEM TO BE SOLVED: To provide a multiple optical axis photoelectric sensor which allows a stable light input state to be recognized easily and is hardly affected by disturbance light.SOLUTION: A floodlight 102 and an optical receiver 104 each have the same multiple number of optical axes Oax, and a beam of light is projected, while being separated in time, for each optical axis Oax from the floodlight 102 toward the optical receiver 104, whereby a light curtain is formed. The optical receiver 104 receives a light beam of three pulses for each optical axis Oax, so that when, for example, two or more pulses are detected on each optical axis Oax, it determines that "light is incident," and when all pulses (three pulses) are detected, it determines that "light is stably incident." Then, the optical receiver 104 determines for all of the first to the fourth optical axes Oax whether light is incident or shaded, and for at least an optical axis Oax which was determined to have incident light, determines whether "light is stably incident." When two pulses or more are detected on all of the optical axes Oax, it turns safe output (OSSD output) on, or when less than two pulses are detected on any optical axis Oax, it turns safe output (OSSD output) off. |
