An image processing method and apparatus that minimizes a delay time until the image is detected and captured when shooting photographs where various shooting options are set. The optical device includes a light-guiding plate; a first optical member reflecting or diffracting the light so as to totally reflect the light inside the light-guiding plate; and a second optical member causing the propagated light to emerge from the light-guiding plate. In this way, the operating device can be isolated from the grid at least during the inactive state.