摘要:
A lens barrel for a zoom lens includes first and second lens groups arranged in the direction of an optical axis. A first rotary barrel is rotatable about the optical axis and is rotated to move the first lens group in the direction of the optical axis, and a second rotary barrel is provided coaxially with the first rotary barrel. A guide groove is provided on the second rotary barrel and guides the second lens group to move it in the direction of the optical axis in response to rotation of the second rotary barrel. A rotation transmission mechanism is disposed between the first and second rotary barrels to be able to engage to rotate both the first and second rotary barrels, thereby zooming the zoom lens, and to be able to disengage to rotate only one of the first and second rotary barrels through a predetermined angle range with the other held stationary so that focusing the zoom lens can be effected by rotating said one rotary barrel within the predetermined angle range.
摘要:
A helicoid structure is disclosed that includes a male helicoid provided on an inner barrel and a female helicoid provided on an outer barrel. The female helicoid includes long female crests having engagement ends positioned near a forward end of the outer barrel and short female crests having engagement ends positioned further from the forward end of the outer barrel. At least one of the short female crests is connected to an adjacent long female crest by a guiding crest respectively formed along a plane extending orthogonally to an axis of the outer barrel. When the inner barrel having the male helicoid is rotated relative to the outer barrel having the female helicoid in order to assemble the inner barrel into the outer barrel, the engagement ends of the male helicoid crests are guided by the guiding crests so that the inner barrel may be rotated without any linear movement relative to the outer barrel.
摘要:
A camera accommodates a main lamp for electronic flashing and an auxiliary lamp for preventing a red-eye phenomenon.The auxiliary lamp for preventing a red-eye phenomenon is directly held by a holder composed of a material of a color having a light reflecting effect such as white. Since the holder also function as a reflecting plate, the structure of the camera is simplified. A transparent cover is integrally provided with at least a finder window, an electronic flash lamp window at which the main lamp for electronic flashing is disposed, and an auxiliary lamp window at which the auxiliary lamp is disposed. The transparent cover is attached to the camera as a part of a case, thereby simplifying the structure of the camera. The auxiliary lamp is preferably disposed in the area between the lens barrel at the central portion and the main lamp. Thus, the arrangement of parts in the camera avoiding waste is realized.
摘要:
A focal length changeable camera has a taking lens system which is changed between at least two different focal lengths, namely, a relatively long focal length suitable for a telephotographic mode and a relatively short focal length suitable for a wide-angle photographic mode, and is equipped with a focal length changing mechanism comprising a rotatable changing member driven by a motor, a lever displacing member provided on the rotatable changing member, a motor switching lever engageable with the lever displacing member for switching a motor switch, and a focal length changing member for changing the focal length of the taking lens upon rotation of the rotatable changing member.
摘要:
A helicoid-structure characterized by width-enlarged parts formed by partially widening the respective troughs, which allow the crests to be linearly moved with the increment per unit rotational angle different from the increment per unit rotational angle with which the crests are linearly moved when they are guided by the troughs alone. In a specific embodiment, a stationary lens barrel is formed in its inner peripheral surface with three troughs, each describing a helical curve of appropriate length, on one hand, and a movable lens barrel is formed on its outer peripheral surface with three crests corresponding to the respective troughs each describing a helical curve of appropriate length, on the other hand. The respective troughs are partially widened transversely of the respective helical curves to form width-enlarged parts and a length of each width-enlarged part is dimensioned to be substantially equal to a length of each crest. When the crests move along the respective troughs and reach the respective width-enlarged parts, the respective crests shift transversely of the respective width-enlarged parts, whereupon an increment of linear movement per unit rotational angle with which the movable lens barrel linearly moves relative to the stationary lens barrel is varied.
摘要:
A driving mechanism is disclosed for photographic lens having a stationary lens barrel, a first driving lens barrel adapted to be rotated and moved back and forth relative to the stationary lens barrel, a second driving lens barrel operatively associated with the first driving lens barrel by the aid of a rotation transmitting structure so as to be rotated and moved back and forth relative to the first driving lens barrel, and a movable lens barrel holding a front lens group and being movable back and forth relative to the second driving lens barrel. With this arrangement, power varying or focusing is achieved with a relatively small-sized lens barrel assembly by moving a rear lens group back and forth under a regulating action of the second driving lens barrel. The first driving lens barrel is rotatably received by and operatively associated with the stationary lens barrel through helicoids formed on these two lens barrels. The second driving lens barrel is rotatably received by and operatively associated with the first driving lens barrel through helicoids formed on these two lens barrels. The movable lens barrel is received by and operatively associated with the second driving lens barrel through helicoids formed on these two lens barrels. Rotation of the first driving lens barrel is transmitted by gears to the second driving lens barrel so as to rotate the second driving lens barrel in a direction opposite to that in which the first driving lens barrel rotates.
摘要:
A photographic camera has a camera back body on which are mounted an electronic circuit assembly including an external display system and the like and a pressure plate which is movable in the direction of the optical axis of a taking lens of the camera and supports the back side of a film loaded in the camera. A spring structure for urging the pressure plate toward the film includes a pair of torsion springs each having a linear shaft portion and a plurality of abutment portions extending substantially perpendicular to the shaft portion. The springs are disposed between the pressure plate and the camera back body so that the shaft portions of the respective torsion springs extend along opposite side edges of the pressure plate and a part of the abutment portions abuts against the pressure plate with the other abutment portions in abutment against a fixed portion on the camera back body. The shaft portions and the abutment portions of the respective torsion springs are disposed in spaces on opposite sides of the electronic circuit assembly without interference with the electronic circuit assembly.
摘要:
A focal length changeable camera has a taking lens system which is changed between at least two different focal lengths, namely, a relatively long focal length suitable for a telephotographic mode and a relatively short focal length suitable for a wide-angle photographic mode, and is equipped with a focal length changing mechanism comprising a rotatable changing member driven by a motor, a lever displacing member provided on the rotatable changing member, a motor switching lever engageable with the lever displacing member for switching a motor switch, and a focal length changing member for changing the focal length of the taking lens upon rotation of the rotatable changing member.
摘要:
An image formation optical unit is provided. In the image formation optical unit, a first shaft formed with a guide shaft and a drive shaft and a second shaft formed with a guide shaft and a drive shaft are disposed side by side so as to extend in parallel with a second optical axis direction. A free space is thus provided in the center and further two motors and are disposed in a free space at the rear of a prism, thereby making it possible to further reduce the dimensions in the height direction.
摘要:
A zoom lens device includes a zoom optical system, in which front, middle and rear lens groups are set at one focal length between a wide-angle end where a focal length is short and a telephoto end where the focal length is long. Lens barrels move in first and second regions to move the front, middle and rear lens groups along an optical axis. The lens barrels, when in the first region, focus the zoom optical system with a predetermined focal length kept by maintaining an interval between the front and middle lens groups, and when in the second region, change the focal length of the zoom optical system. A combination of a cam follower pin and a cam groove effects focusing by moving the middle lens group relative to the front lens group along the optical axis when the lens barrels are in the second region.