Alarm device for vehicle

An alarm device for a vehicle detecting an approach of another vehicle and generating an alarm comprising:

• a vehicle detector detecting an approach of another vehicle from behind;
• an operation detector arranged on a door body, and detecting an approach of a hand of a passenger to an opening and closing operation section of the door body;
• an alarm generator generating the alarm to the passenger;
• a controller generating an alarm on the alarm generator when the vehicle detector detects the approach of the another vehicle, and the operation detector detects the approach of the hand of the passenger;
• a warning light arranged on the door body and configured to illuminate light backward;
• and
• an opening operation detector detecting that the door is opened,
• wherein the vehicle detector measures at least one of a distance from the another vehicle and a speed of the another vehicle, and
• wherein when the vehicle detector detects the approach of the another vehicle, and the opening operation detector detects that the door is opened, the controller controls the warning light blinking with a cycle corresponding to at least one of the distance from the another vehicle and the speed of the another vehicle.