Display apparatus and control method for display apparatus

A control method for a display apparatus comprising a laser radiation device configured to radiate laser light of a predetermined wavelength range to a display position in a gas to form a plasma in the display position, the control method comprising:

• detecting in which an object detection device detects presence or absence of an object in a predetermined space determined on a basis of the display position and intensity of the laser light scattered in the display position or having passed the display position;
• and
• controlling in which, in a case where the object detection device has detected the object in the predetermined space, a control device stops or reduces an output of the laser radiation device and changes a position or a shape of the predetermined space.