The camera and the eye are similar in many respects. They both need light rays in order to function. Both have a sensitive surface on which the image is formed. In the eye the image is formed on the retina. In the camera the image is formed on the film. As in a camera, the image on the retina is inverted.
Both the eye and the camera have a lens. The lens focuses the image on the sensitive surface. In the camera, the lens moves backward and forward. In the eye the curvature of the lens is changed. In this respect the eye differs from the camera.
Both the camera and the eye have a device to regulate the amount of light that passes through the lens. In the camera there is a shutter of variable speed and a diaphragm of variable aperture. In the eye the iris automatically adjusts the size of the pupil according to the intensity of light.
Both the eye and the camera are sensitive to light, shade and color. The film records light, shade and color. The eye perceives them but does not record them. The two eyes together produce a three-dimensional image. The camera lens produces a two-dimensional image.
The eye is more flexible than the camera. It can adapt more quickly to a wider range of light conditions. Both the camera and the eye can register small and distant objects. The camera performs these functions better than the eye.
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【正确答案】：inverted