Display system and detection method

A detection method in a display system detecting selection of an object included in a two-dimensional image displayed in a midair display region,

• said display system including a display, an optical element displaying said two-dimensional image based on an image displayed on said display, a sensor including a light-emitting element and a plurality of light-receiving elements, a processor electrically connected to said sensor and causing said display to display the image for displaying a plurality of objects as said two-dimensional image in said display region in a manner arranged in a predetermined orientation, and a memory electrically connected to said processor, said memory prestoring data which associates numerical value ranges different from each other with said plurality of objects, respectively,
• said detection method comprising the steps of:
• said light-emitting element emitting light to said plurality of objects in said predetermined orientation;
• at least one of said plurality of light-receiving elements receiving light reflected by a body, of said emitted light;
• said processor calculating, when said reflected light is received by said sensor, the number of the light-receiving elements that have received said reflected light;
• said processor identifying one said object associated with said numerical value range including said calculated number of the light-receiving elements, from among said plurality of objects;
• and
• said processor performing processing corresponding to said identified object.