Laser line projector for lateral cephalograms digital radiography

A laser line projecting device for a lateral cephalometric radiograph device, which is provided in the lateral cephalometric radiograph device including a support (1), a detector (2) extending downward from one side of the support (1), and ear rods (3) extending downward from the support (1) and adapted to be coupled to both ear holes of a user,

• the laser line projecting device comprising:
• a support rod (10) extending downward from a lower surface of the support (1), wherein the support rod (10) includes:
• a fixed block (11) fixed to the lower surface of the support (1);
• and
• a rod body (12) extending in the vertical direction and having an upper end detachably coupled to the fixed block (11);
• a projection unit (20) provided on the support rod (10) and configured to project linear light onto a face of the user adapted to be fixed to the ear rods (3), wherein the projection unit (20) projects a vertical line (21) extending in a vertical direction adapted to pass through a center of the user's face or a horizontal line (22) extending in a horizontal direction passing through a midpoint determined by both of ear plugs which are adapted to be coupled to the ear holes of the user;
• a coupling detecting unit (30) provided at an upper end of the rod body (12) and configured to detect whether the rod body (12) is coupled to the fixed block (11);
• a camera (40) provided on a lower rear surface of the rod body (12) to face a rear side and configured to photograph the user's face and locations of the vertical line (21) or the horizontal line (22) projected onto the face;
• and
• a control unit (50) connected to the coupling detecting unit (30) and the camera (40) and configured to control operation of the projection unit (20),
• wherein the control unit (50) is equipped with an image analysis program (51) for analyzing an image captured by the camera (40) and turns off the projection unit (20) when it is detected through the coupling detecting unit (30) that the upper end of the body rod (12) is separated from the fixed block (11) or it is detected by analyzing the image captured by the camera (40) that light output from the projection unit (20) is projected to a location close to the user's eyes.