Projection apparatus that performs rotation correction

A projection apparatus comprising:

• a housing;
• a projection lens that has a holder and that is rotatably attached to the housing;
• a detection unit, including a sensor, that detects a rotation state of the holder;
• an image output unit including an electro-optical element that outputs a first image output from an external device to the projection lens that projects the first image in a projection direction;
• and
• a controller that performs rotation correction on the first image based on a detection result of the detection unit without input by a user, wherein:
• when the holder is rotated by 90°, the first image is rotated by 90° around the projection direction and becomes a first vertically displayed image having a long side in a top-bottom direction;
• when the holder is rotated by 270°, the first image is rotated by 270° around the projection direction and becomes a second vertically displayed image having the long side in the top-bottom direction;
• and
• the controller automatically arranges an orientation of the first vertically displayed image and an orientation of the second vertically displayed image to be identical to each other by performing the rotation correction on the first image by 180° when the detection unit detects that the holder has been rotated by 90°, and not performing the rotation correction on the first image when the detection unit detects that the holder has been rotated by 270°.