Image rotating adapter and camera having the same

An image rotating adapter, a camera that includes a camera body, an imaging lens detachably mounted to the camera main body, the image rotating adapter detachably mounted between the imaging lens and the camera main body, wherein a subject image passing through the imaging lens is formed on a light receiving surface of an image pickup device through a prism built in the camera main body, and the image rotating adapter rotates the subject image formed on the light receiving surface of the image pickup device, the image rotating adapter comprising:

• a first prism that has an optical path length approximate to the optical path of the prism built in the camera main body, wherein the first prism is disposed in an optical path before the subject image passing through the imaging lens is formed on a position in the image rotating adapter, and the first prism reflects subject light passing through the imaging lens odd number of times, and reverses the subject image passing through the imaging lens;
• a second prism that has the incident optical axis and the exit optical axis formed on the same axis, wherein the second prism is disposed on an optical axis of the subject light after the subject image is formed once through the first prism, the second prism is supported to freely rotate around the optical axis, and the second prism reflects the subject light passing through the first prism odd number of times and further reverses the subject image reversed by the first prism;
• a relay optical system that forms again the subject image passing through the second prism on the light receiving surface of the image pickup device;
• a rotation drive unit that rotates the second prism;
• a control unit that controls the rotation drive unit;
• a rotation instruction unit that instructs the control unit to start or stop rotation;
• a target position setting unit that previously sets one or more target positions to stop the second prism;
• a preset instruction unit that instructs the control unit to perform a preset function for moving the second prism to the target position;
• and
• a detection unit that detects a rotation position and a rotation direction of the second prism,
• wherein the control unit performs a position control to move the second prism to the target position by the rotation drive unit based on the detection result of the detection unit when being instructed to perform the preset function.