Patent ID: 8242898

Claim:
A turn signal illumination controller for controlling illumination of a turn signal indicator when a turn signal operation member of a vehicle is operated, the turn signal illumination controller comprising: an angular velocity detection unit that detects an angular velocity of the vehicle when the vehicle changes its travel direction; a vehicle bearing angle variation calculation unit that calculates a vehicle bearing angle variation amount per unit time when the travel direction is changing based on a detection value of the angular velocity detection unit; a vehicle bearing angle calculation unit that calculates a vehicle bearing angle when the travel direction is changing based on the vehicle bearing angle variation amount obtained by the vehicle bearing angle variation calculation unit; a lateral movement distance calculation unit that calculates a lateral movement distance of the vehicle when the travel direction is changing based on the vehicle bearing angle obtained by the vehicle bearing angle calculation unit; and a cancellation execution unit that cancels the illuminated turn signal indicator when the calculated lateral movement distance is greater than or equal to a threshold value.