Automatic focusing camera

Abstract

An automatic focusing camera is equipped with an automatic subject distance detecting device for detecting which of a plurality of predetermined distances is nearest to that at which the subject lies. A lens positioning member adjusts an objective lens to a suitable focusing position in which the objective lens has a depth of field straddling that nearest predetermined distance detected by the automatic subject distance detecting device. Another lens positioning member adjusts the objective lens to a focusing position in which the objective lens will be focused on a subject, such as a landscape, at infinity, independently of the distances detected by the automatic subject distance detecting device. The latter objective lens positioning member is externally operable when it is intended to photograph a subject at infinity, before depressing the shutter button.

What is claimed is: 
     
       1. An automatic focusing camera comprising: distance detecting means for detecting the distance of a subject to be photographed and providing a distance signal; first lens positioning means for positioning an objective lens to a finite suitable focusing position according to said distance signal.Iadd., within a range from a close focusing position in which said objective lens focuses at a predetermined closest distance to a far focusing position in which said objective lens focuses at a predetermined far distance and covers infinity by a depth of field of said objective lens.Iaddend.;   second lens positioning means for positioning said objective lens at a focusing position suitable for infinity independently from said distance signal.Iadd., in which said objective lens focuses at a distance farther than said predetermined far distance, said second lens positioning means being operable under the condition that infinity is covered by the depth of field of the objective lens in the far focusing position.Iaddend.; and   externally operable means for actuating said second lens positioning means to position said objective lens only at said focusing position suitable for infinity.   
     
     
       2. A camera as defined in claim 1, having a shutter and a manually-actuable shutter release member, said externally-operable means for actuating said second lens positioning means being operable to do so only upon simultaneous manual actuation of said shutter release member and said externally-operable means by a user of the camera. 
     
     
       3. An automatic focusing camera of the type in which an objective lens is selectively adjusted to any of a plurality of suitable focusing positions, said camera comprising: means for detecting the distance of a remote subject to be photographed and providing a distance signal;   first adjusting means for adjusting said objective lens to one of said plurality of suitable focusing positions according to said distance signal.Iadd., within a range from a close focusing position in which said objective lens focuses at a predetermined closest distance to a far focusing position in which said objective lens focuses at a predetermined far distance and covers infinity by a depth of field of said objective lens.Iaddend.;   second adjusting means for adjusting said objective lens to a focusing position suitable for infinity . .rather than one of said plurality of suitable focusing positions.!..Iadd., said focusing position suitable for infinity being outside of said range, said focusing position suitable for infinity causing said objective lens to focus at a distance farther than said predetermined far distance, said second lens positioning means being operable under the condition that infinity is covered by the depth of field of the objective lens in the far focusing position.Iaddend.; and   externally operable means for actuating said second adjusting means to adjust said objective lens only to said focusing position suitable for infinity.   
     
     
       4. A camera as defined in claim 3, having a flash unit attached thereto, and means for preventing triggering of said flash unit when said second adjusting means is actuated. 
     
     
       5. A camera as defined in claim 4, wherein said preventing mans includes an AND circuit and a trigger circuit connected to said AND circuit. 
     
     
       6. A camera as defined in claim 3, having a shutter and a manually-actuable shutter release member, said externally-operable means for actuating said second lens positioning means being operable to do so only upon simultaneous manual actuation of said shutter release member and said externally-operable means by a user of the camera. 
     
     
       7. A camera equipped with an objective lens which is selectively adjustable to suitable focusing positions according to subject distances, said camera comprising: automatic subject distance detecting means comprising a light projecting means for projecting light to a subject to be photographed and a light receiving means for detecting light reflected from said subject and providing an electric distance signal corresponding to the distance of said subject;   first lens positioning means for positioning said objective lens at one of said suitable focusing positions . .in which said objective lens has a depth of field such as to include a finite said subject distance to which said distance signal corresponds.!. .Iadd.according to said distance signal, within a range from a close focusing position in which said objective lens focuses at a predetermined closest distance to a far focusing position in which said objective lens focuses at a predetermined far distance and covers infinity by a depth of field of said objective lens.Iaddend.;   second lens positioning means for positioning said objective lens at a focusing position suitable for infinity . .rather than at said focusing position for a said infinite subject distance.!..Iadd., said focusing position suitable for infinity being outside of said range, said focusing position suitable for infinity causing said objective lens to focus at a distance farther than said predetermined far distance, said second lens positioning means being operable under the condition that infinity is covered by the depth of field of the objective lens in the far focusing position.Iaddend.; and   externally operable means for actuating said second lens positioning means to position said objective lens only at said focusing position suitable for infinity.   
     
     
       8. A camera as defined in claim 7, having a shutter and a manually-actuable shutter release member, said externally-operable means for actuating said second lens positioning means being operable to do so only upon simultaneous manual actuation of said shutter release member and said externally-operable means by a user of the camera.