The present invention relates to a photographic camera. More particularly, it relates to a multiple-lens camera wherein each lens can be selectively moved to and from a picture-taking position.
In motion-picture cameras it is known to provide two or more objectives, i.e., lenses, which are mounted on a slidable or rotary carriage and can be selectively moved into picture-taking position in which the respective lens is located on the optical axis of the camera. Such lenses may e.g., be a normal and a telephoto lens, or a normal and a wide-angle lens. An analogous arrangement has also been proposed for still cameras.
It is desirable to use such an arrangement also with the new small cameras which use film casettes, for example "type 110" cassettes. Here, however, a space problem is encountered. One of the purposes of developing these cassettes was to be able to construct small-dimensioned cameras, such as the so-called "pocket" cameras. The cassettes have an elongated web provided with the film-exposure window; at the opposite ends of the web are provided two chambers which project beyond the plane of the web (forwardly in the longitudinal direction of the optical axis when the cassette is located in the camera) and which respectively contain the supply and take-up roll for the film.
The lenses are mounted in the camera forwardly of the compartment for the cassette. If they are to be moved transversely of the optical axis into and out of picture-taking position, problems are encountered in view of the forwardly projecting film chambers of the cassette; because of the desire to keep the camera dimensions small, these problems cannot be solved by increasing the size of the camera housing to provide adequate space for the lens having the shortest focal length.
One theoretically possible solution would be to use a retro-focus arrangement of the type employed in conjunction with wide-angle lenses in single-lens reflex cameras. In practice, however, this solution is not feasible, because of the relatively great expense of such arrangements and also because in these arrangements the front lens must have an undesirably large diameter.
USPTO Backgrounds
USPTO Backgrounds