| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a new system for providing pre-caution and pre-information to a road user with an optical signal device. SOLUTION: This system is constituted so that a signal device is operated for a short duration time at least once, and the duration time is selected so as to be present in the lower part of the threshold of conscious perception of the road user but in the upper part of the threshold of unconscious perception.</p> |
