Abstract:
Disclosed herein is a camera having a shutter mechanism; actuating means for actuating the shutter mechanism; and, an aperture selecting assembly that is movable from an initial mode position to at least a first mode position. Also disclosed is an aperture selector assembly that is coupled to the shutter actuating mechanism and includes a slide that is selectively movable from an initial mode position to one of a plurality of aperture selecting positions. During slide movement to the desired aperture setting, the strobe is energized and the energy to operate the shutter is stored in a spring. At the desired position, the selector slide is detented by a first clasping device until a shutter button is actuated for releasing the shutter and firing the strobe. A second clasping device becomes operative during shutter actuation to hold the slide in position even though the detent of the first clasping device has been released.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     The present application claims priority to provisional application Ser. No. 60/233,005, filed Sep. 15, 2000. The present application is related to copending provisional patent application filed in the United States Patent and Trademark Office on Aug. 9, 2000, having Ser. No. 60/223,958 and entitled “Compact Photographic Camera”; and, copending patent application Ser. No. 09/952,549 entitled “Compact Photographic Apparatus of the Self-Developing Type” filed in the United States Patent and Trademark Office on even date herewith. 
    
    
     BACKGROUND OF THE INVENTION 
     The present invention relates generally to compact photographic apparatus and, more particularly, to compact cameras that have simplified selectors and actuators for performing multiple camera functions in combination with other camera elements in regard to self-developing imaging apparatus. 
     The prior art is characterized by numerous efforts to make photographic cameras simplified and compact not only in terms of their construction, but their operation as well. In addition, such efforts have included approaches for ensuring that an operator, especially younger ones, need not be unduly concerned with the camera operations both prior to and following exposure. In further addition, efforts have been undertaken to make construction of the cameras economical. Known approaches include those self-developing photographic cameras as described in U.S. Pat. No. 5,870,633 issued to Norris and U.S. Pat. No. 6,099,172 issued to Togashi et al.; both of which are commonly-assigned to Polaroid Corporation. 
     Furthermore, the prior art is characterized by numerous efforts to make photographic cameras of the self-developing type simplified and compact with respect to user interfaces relating to selections of different camera modes, such as aperture, exposure and illumination. Examples of known approaches in this area are described, for example, in U.S. Pat. No. 3,839,607 issued to Ogihara; and U.S. Pat. No. 5,867,742 issued to Salvas et al. The latter patent describes a manual selector that is movable from an initial mode position to anyone of a plurality of discrete mode setting positions, whereby the selector is also operable for actuating a strobe unit in some of the selected modes. This patent describes means for automatically returning the manual selector to the initial mode position following a camera operating cycle. Commonly-owned U.S. Pat. No. 6,099,172 relates to a simplified mechanism for selecting apertures to different camera modes of operation, as well as effecting shattering operations, and automatic return of the components to an original or unactuated condition. The latter patent describes such a mechanism for use in a commercially successful camera particularly adapted to a self-developing film frame removed manually from the camera following exposure, with such withdrawal effecting processing of the exposed film unit, indexing of a subsequent film unit, and singulation of the pulled unit. 
     Despite the existence of these known approaches, however, there is nevertheless a continuing desire to make improvements in the overall ease and reliability of their operation as well as simplification and compactness of the camera construction, while not sacrificing system performance. 
     SUMMARY OF THE INVENTION 
     According to the principles of the present invention provision is made for a camera having a shutter mechanism; actuating means for actuating the shutter mechanism; and, an aperture selecting assembly that is movable from an initial mode position to at least a first mode position in response to manipulation thereof for setting at least one exposure aperture. The actuating means includes a finger engageable portion that is biased to a first position and when depressed by a force applied thereto is movable to a second position for actuating the shutter mechanism. Provision is made for an aperture selector assembly coupled to the shutter actuating mechanism and includes a slide that is selectively movable from an initial mode position to one of a plurality of aperture selecting positions. During slide movement to the desired aperture setting condition the strobe is energized and the energy to operate the shutter is stored in a spring. At the desired position, the selector slide is detented by a first clasping device until a shutter button is actuated for releasing the shutter and firing the strobe. A second clasping device becomes operative during shutter actuation to hold the slide in position even though the detent of the first clasping device has been released. The slide is automatically returnable to its original position following exposure by the operator removing pressure from the shutter button and turning off the power to the strobe to preserve battery life. 
     OBJECTS OF THE PRESENT INVENTION 
     It is an object of the present invention to provide a camera of the self-developing type that is compact in its architecture and simplified in operation. 
     It is an object of the present invention to provide a camera of the self-developing type that has a compact architecture and yet is highly reliable in operation. 
     It is an object of the present invention to provide a camera of the self-developing type that has a compact architecture and yet is highly reliable in operation without any loss in performance. 
     It is an object of the present invention to provide a camera of the self-developing type that has a compact architecture and yet is relatively economical to manufacture and assemble. 
     It is an object of the present invention to provide for a simplified camera that is user friendly and reliable in operation; particularly for young and inexperienced camera operators. 
     It is an object of the present invention to provide for a simplified camera of the above type that returns the selector automatically to an initial mode setting position. 
     It is an object of the present invention to provide a camera having mechanisms for selecting camera modes and actuators that are operable for actuating multiple camera functions including aperture selection, shattering, and strobe firing. 
     It is an object of the present invention to provide for a camera having a selector that is manually displaceable for selecting multiple camera modes by having selector move from an initial mode setting position to any one of a plurality of operating mode positions, and subsequently returning automatically to the initial mode setting position following shutter operation. 
    
    
     Other objects and further scope of applicability of the present invention will become apparent after reading a detailed description when taken in conjunction with the accompanying drawings wherein like reference numerals indicate like structure throughout the several views. 
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of a self-developing camera embodying features of the present invention. 
     FIG. 2 is a partially exploded perspective view of the camera illustrating removable and decorative panels. 
     FIG. 3 is an exploded perspective view illustrating several subassemblies of the camera. 
     FIG. 4 is a schematic elevation view illustrating several of the operating components in the interior of the camera. 
     FIG. 5 is a schematic elevation view illustrating several of the operating components of the interior of the camera. 
     FIG. 6 is a perspective view of a partial portion of the camera of the camera in the open film loading condition. 
     FIG. 7 is a plan view of the components of the aperture and shutter mechanism of the present invention in one condition. 
     FIG. 8 is an elevation view of the components depicted in FIG.  7 . 
     FIG. 9 is a plan view of the operating components of the aperture and shutter mechanism of the present invention in a different operating condition. 
     FIG. 10 is an elevation view of the components depicted in FIG.  9 . 
     FIG. 11 is a plan view of the operating components of the aperture and shutter mechanism of the present invention in a still further different operating condition. 
     FIG. 12 is an elevation view of the components depicted in FIG.  11 . 
     FIG. 13 is a plan view of the operating components of the aperture and shutter mechanism of the present invention in a still further different operating condition. 
     FIG. 14 is an elevation view of the components depicted in FIG.  13 . 
     FIG. 15 is a plan view of the operating components of the aperture and shutter mechanism of the present invention in a still further different operating condition. 
     FIG. 16 is an elevation view of the components depicted in FIG.  15 . 
     FIG. 17 is a plan view of the operating components of the aperture and shutter mechanism of the present invention in a still further different operating condition. 
     FIG. 18 is an elevation view of the components depicted in FIG.  17 . 
     FIG. 19 is a plan view of the operating components in another view. 
     FIG. 20A is an enlarged partial view of the cooperation between a cam and clasping portion. 
     FIG. 20B is an enlarged partial view of the cooperation between the components of FIG.  19 A. 
     FIG. 21 is an elevation view of the components depicted in FIG.  19 . 
     FIG. 22 is an elevation view of the operating components of the aperture and shutter mechanism of the present invention wherein the shutter post forces a hammer latch to release the hammer for initiating an exposure. 
     FIG. 23 an elevation view of some components illustrated in FIG.  22 . 
     FIG. 24 is a plan view illustrating the hammer pivoting an aperture slide detent out of engagement, and triggering a strobe fire switch. 
     FIG. 25 is an elevation view of the components depicted in FIG.  24 . 
     FIGS. 26A and 26B illustrate operation of the strobe fire switch during movement of the hammer depicted in FIGS. 24 and 25. 
     FIG. 27 is a plan view of the operating components of the aperture and shutter mechanism of the present invention wherein the shutter button is released and a clasp moves out of a detent. 
     FIG. 28 is an elevation view of the components depicted in FIG.  27 . 
     FIG. 29 is a plan view of the operating components of the aperture and shutter mechanism of the present invention with the slide selector being forced back to the original “off” position. 
     FIG. 30 is an elevation view of the components depicted in FIG.  29 . 
     FIG. 31 is a perspective view of the aperture selector of the present invention. 
    
    
     DETAILED DESCRIPTION 
     Reference is made to FIGS. 1-6 for illustrating one preferred embodiment of a compact camera  20  of the self-developing type that is made in accordance to the principles of the present invention. Included in the camera  20  is a light-tight housing assembly  22  that essentially comprises a main frame assembly  24 , an upper casing shell or member  26 , a lower casing shell or member  28 , and an electrical strobe board  30  that carries the electrical components for operation of the camera. 
     The upper casing member  26  defines an elliptical recess  32  for accommodating in a generally flush relationship thereto a decorative and removable top panel  34  that a user can replace in order to change styling of the camera. The decorative top panel  34  is latched to the upper casing. The upper casing  26  has an opening for accommodating a shutter button  36  and an elongated slot  38  for an aperture selector tab  40 . 
     The upper and lower casing members are suitably joined together to enclose the main frame assembly  24  and define an elliptical recess  41  in the front thereof for accommodating a decorative and replaceable front panel  42 . The front panel  42  is latched to the housing assembly  22  so as to fit generally flush within the recess  41 . The front panel  42  has a strobe opening  44 , a taking lens opening  46 , and a viewfinder opening  48 . 
     The lower casing member  28  has an enlarged generally rectangular opening  50  sized for allowing a film loading door  52  to move pivotally between open and closed conditions. As a consequence, a film assembly is allowed to be inserted and removed. 
     Provision is made for a generally rectangular retaining plate  56  that has a taking lens aperture  58  and a viewfinder aperture  60  that is mounted on the main frame assembly  24  and is enclosed within the casing members  26 ,  28 . 
     Reference is made back to the main frame assembly  24 , wherein provision is made for a film box cavity  62  that is sized for removably receiving a film package (not shown) that stores the film assemblage  54  in a light-tight relationship. By virtue of such a condition being achieved, it is possible to make the surrounding upper and lower casing members of a transparent material without the risk of damaging the film. The film assemblage  54  is, preferably, of the self-developing kind that is particularly adapted for use in a camera of the above type. The film assemblage is similar in construction to those described in commonly-assigned U.S. Pat. Nos.: 5,838,999 and 5,888,693, and hence, the descriptions thereof are incorporated herein and made a part hereof. However, only those portions of the film assemblage  54  necessary to understand the present invention will be set forth herein. In this regard, the film assemblage is in the form of an elongated strip  64  with separable individual film frames  66  housed in a folded and stacked relationship within the film package or cassette. A leading tab  68  of each frame  66  is adapted to protrude from an exit slot  70  (FIG. 4) and a spring-biased film flap  72  is pivotally mounted adjacent one end of the camera housing, whereby an operator can grasp and pull the film assemblage for indexing the latter. 
     The film flap does not, per se, form an aspect of the present invention. A detailed description thereof is described in the last noted patent application and is incorporated herein and made a part hereof. The film frames  66  are frangibly connected to each other, whereby they separate into individual frames when the film strip is pulled from the housing assembly. Thus, when an operator pulls on a leading tab  68  of an exposed film frame, the film is advanced thereby effecting processing of an exposed film unit as the latter is withdrawn from a focal plane  74  and passes through a nip defined by a pair of processing rollers  80   a, b  (FIG.  4 ). As a result, each of the emerging and distal end film frames separate from a successive film frame that has been simultaneously indexed from the film cavity which has its leading tab emerge. 
     Continued reference is to FIGS. 4-6 wherein the film loading door  52  is pivotally mounted to one end of the main frame housing assembly  24  adjacent a film flap  72 . The spread roller  80   a  is mounted for rotation on the door  52  adjacent a pre-spread feature  82  that is mounted on the door immediately prior to a nip defined by and between the rollers  80   a  and  80   b . A latch  84  is located at one end of the film loading door  52  and cooperates with a complementary catch for releaseably securing the door in a closed relationship with the main frame assembly. A more complete description this structure is found in commonly filed patent application (Case 8453Pro) noted above which is incorporated herein and made a part hereof. The camera is also envisioned to be a one-time use camera, whereby the door would be locked against customer opening and the film preloaded prior to being locked. 
     For defining the focal plane  74  there is provided a taking lens  86 , a mirror  88 , and a focal cone  90  defined by and at the bottom of the main housing assembly  24 . The taking lens  86  is mounted by the retaining plate and is generally positioned to reduce the height of camera relative to, for example, the camera described in U.S. Pat. No. 6,099,172. The taking lens  86  is positioned more laterally with respect to a longitudinal axis of the camera while retaining the same focal length as the taking lens in the noted patent. This relationship in turn lowers the mirror, thus reducing the height profile. The focal cone  90  is defined to accommodate the size format of the film. Adjacent the focal cone  90  is a film path defining ramp  92  that serves to reduce the height of the camera. The spread roller  80   b  is spring biased and is mounted for rotation in the bottom wall of the main frame assembly  24 . The spread roller  80   b  defines a nip with roller  80   a  whenever the loading door is in the closed condition. One viewfinder lens  94  of the viewfinder assembly  96  is retained by the retaining plate  46 . The viewfinder assembly  96  can be anyone of several kinds. 
     As illustrated, a pair of generally parallel battery receiving cavities  97   a ,  97   b  are mounted in close proximity to the viewfinder assembly  96  and the shutter button  36 . The battery receiving cavities lie in a plane that includes the viewfinder assembly  96  for purposes of establishing a compact relationship. Batteries (not shown) engage with the battery contacts  98 . A battery compartment door  99  is provided. 
     A flash tube assembly  112  of any suitable type is mounted on the strobe board  30  as illustrated for use in generating pulses of artificial illumination directed at the scene. A capacitor  114  is provided for energizing the flash tube assembly  112  and is mounted on an underside surface of the strobe board  30  with its axial length extending along a bottom surface of the strobe board and generally parallel to such bottom surface. 
     The horizontally mounted strobe board  30  has an aperture  116  that is configured and sized to fit over and surround the periphery of an aperture selector mechanism  120  made according to the principles of the present invention. The aperture  116  also encloses a top portion of the mirror housing, thereby lowering the overall height of the camera. Included in the aperture selector mechanism  120  is an elongated aperture selector slide  122  that is mounted for slidable movement on the main frame assembly  24  and is otherwise manually displaceable by an operator to one of several distinct aperture settings corresponding to, for example, iconographic information or symbols (not shown) on the exterior of the housing. The aperture selector slide  122  is housed and guided for movement by a slide retainer housing  124 ; both of which have their longitudinal axes generally parallel to each other and a top surface of the strobe board  30 . The slide and its retainer are generally centrally disposed along the length of the camera and are positioned to be above the taking lens. 
     Reference is initially made to FIGS. 7 and 8 for illustrating an improved shutter and aperture selector assembly or mechanism  120  in a rest or “OFF” condition. A shutter link  126  has a wing portion  126   a  that is engaged by a plunger  53  on the shutter button  36 . The shutter link  126  is pivoted about an axis  127  and has another wing portion  126   b  with a cam  128  at a distal end thereof. The cam  128  engages a complementary surface on a clasping or detenting mechanism  130  for reasons to be described hereinafter. It will be further appreciated that the clasp can only engage and stop the slide when it the former is in one of the notches. If the clasp engages at any location other than the notches the shutter is prevented from further operation. 
     The aperture selector assembly  120  includes an elongated and generally flat aperture selector slide  122  that is partially enclosed by aperture selector slide retainer  124 . The slide  122  is mounted on tracks, not shown, on the main housing assembly for allowing its reciprocal movement. A protrusion  132  protrudes upwardly from the slide  122  and is free to travel in an axial direction in an elongated slot  134  formed in the slide retainer  124 . The protrusion  132  cooperates with the aperture selector tab  132  that protrudes through a corresponding slot in the plate  34  for allowing a user to displace the slide from its “off” position (FIGS. 7&amp;8) to the one of three distinct settings (not shown) corresponding to “indoor”; “sunny” or “partly cloudy” conditions. The slide  122  has an elongated cut-out  136  located on a bottom surface and positioned adjacent one lateral side thereof for defining a hook or shoulder  138  that is adapted to cooperate with a radially protruding hammer tab  148  of a rotatable hammer bypass device  150 . 
     A shutter hammer  152  is mounted for rotation on the same axis as the bypass device  150  and is adapted to be driven by the latter. However, the hammer  152  moves independently of the hammer bypass  150  for reasons to be made evident. The hammer  152  is shown in a non-cocked or raised condition for either its first exposure or following a previously completed exposure. As will be described, the hammer  152  when actuated is adapted to trip a shutter blade  154 . The shutter blade  154  is spring biased by a shutter spring  156  to a scene light blocking or closed position covering aperture  158  of the taking lens. 
     FIGS. 9 &amp; 10 illustrate the aperture selector slide  122  in a position after it has been displaced by an operator, from it rest condition (FIGS. 7 &amp; 8) towards a desired aperture setting condition; but before it arrives the aperture setting condition. During this early phase of displacement, the shoulder  138  drivingly engages the tab  148  for rotating the bypass device  150 , against a spring bias by a spring  151  (FIG. 10) that has an arm portion thereof engaging a surface of the device. Since the bypass device  150  is in engagement with a pin on the side of the hammer  152 , the latter is likewise rotationally displaced to its cocked condition (see FIGS.  12  and  14 ). The hammer when so driven stretches a hammer spring  160  attached at one end thereof for providing energy for operating the shutter. The hammer is latched in its cocked condition (FIGS. 11 &amp; 12) when a portion  162  thereof engages a surface on a flexibly resilient hammer latch  164  in the same manner as described in the last noted patent. It will be noted that if the user decides not to take an exposure after cocking the hammer, the slide  122  can be moved back to its original or “off” position without requiring a firing of the shutter. This can happen since the bypass  150  is independently rotatably with respect to the hammer in the opposite direction. Toward this end, a shoulder  145  on the cut-out  144  can override the tab  148  when returning because the bypass is independently rotatable with respect to the hammer. It will be noted that the slide  122  returns automatically to the original position under the influence of a clasp spring  166  mounted on the main frame assembly  24  as will be described. 
     Reference is made to FIG. 13 for better illustrating how the strobe  112  is powered “on” in response to displacement of the slide  122 . In this regard, a strobe power switch  170  connected to the strobe board  30  has an elongated spring arm  170   a  having a distal end biased into engagement with a side of the slide  122  to maintain the switch in an open or “off” condition as illustrated in FIGS. 7,  9  and  11 . However, as the slide member  122  is moved to a first aperture setting position (FIG. 13) switch arm  170   a  follows a cam surface  172  onto a reduced width portion of the slide, thereby closing the switch and thus effecting energization of a strobe capacitor. Thus, the strobe will be energized during aperture select without the user having to make a conscious decision to use the strobe. It will be appreciated that the strobe will be fired in each of the aperture settings. 
     FIGS. 13 and 14 illustrate an arrangement of components wherein the slide  122  is detented in the first aperture setting condition. In this condition, a slide detent member  174  is pivotally mounted on the slide housing  124  and has a tapered distal end  176  that is urged into a first aperture setting detent notch  178   a  by a clasp spring  180 . It will noted that the detent notch  178   a  corresponds to the “indoor” aperture setting. For effecting this detenting operation, a clasp spring  180  has an end  180   a  engaging a projection on the slide housing  124  and another end  180   b  engaging a surface of the detent member  174 . The spring  180  urges the distal end  176  into the notch  178   a  when there is registration between the latter. However, it will be further noted that the clasping mechanism  130  is maintained out of engagement with the slide  122  during the aperture setting mode. It will be further noted that there are three notches  178   a-c , each corresponding to one of the three aperture settings. 
     In the first aperture setting position shown in FIG. 12, it will be further noted that aperture plate  182  is pivotally mounted at  184  to the main frame assembly and remains out of an overlying relationship with the aperture  156 , thereby not modulating incident scene light to the film plane during the indoor exposure. 
     FIGS. 15 &amp; 16 illustrate a second aperture setting position corresponding to a “sunny” scene condition. To reach this setting, an operator further displaces the slide  122  until the selector tab  40  is positioned adjacent the “sunny” iconographic setting on the camera. At this location, the distal end  176  engages the detent notch  178   b  under the influence of the spring  180 . It will be understood that during sliding movement, a depending shoulder  186  of the slide  122  extends downwardly and into the path of an aperture plate pin  188 . As the slide  122  is displaced, the shoulder  186  and an accompanying recess  187  trap the pin and effect rotation of the aperture plate so that an aperture  190 , corresponding to an appropriate f-number for “sunny” conditions, is in optical alignment with the exposure aperture  156 . The aperture plate  182  is positively locked into an overlying optical registry with the exposure aperture  156 . 
     FIGS. 17 &amp; 18 illustrate the components when the aperture select mechanism  120  is in its third aperture setting condition corresponding to, for example, “partly sunny” conditions, whereby an aperture  192  on the plate is in alignment with the exposure aperture  156 . The aperture  192  is set when the slide  122  and its depending shoulder  186  drive rotatably the aperture plate  182  until the distal end  176  of the slide detent  174  is driven into engagement with detent notch  178   c  and thus resist movement of the slide  122 . The aperture  192  has an appropriate f-number that corresponds to a so-called “partly sunny” scene condition. 
     FIGS. 19 &amp; 21 illustrate a shutter actuating procedure and, in particular, the positioning of several components following the shutter button  36  being depressed by an operator. In such a position, the shutter link  126  has been pivoted upwardly and effects swinging movement of the clasping mechanism  130  from an inoperative position to an operative or clasping position (FIG.  19 ). In particular, the cam  128  while pivoted upwardly rides on and drives an inclined surface  200  about 45 degrees with respect to a vertical plane on a clasping arm portion  204  of the clasping mechanism  130  about a vertical axis  206 ; whereby a distal end  208  of a clasping arm  209  engages a notch  210   a  formed on a side of the slide  122 ; thereby retaining the latter until the clasping mechanism  130  is released in a manner to be described. It will be noted that the slide  122  includes a series of detent notches  210   a-c  corresponding in position with the detent notches  178   a-c  so that the clasping mechanism holds the slide until it is by an operator releasing the shutter button. 
     Referring back to the shutter link  126 , its upward movement drives a link pin  212  that engages and moves the hammer latch  164  so as to release the hammer  152 , whereby the latter is rotated upwardly by the hammer spring  160  to trip the shutter  154  to commence opening of the shutter aperture  156 . The shutter  154  will then be driven back to its closed position, thereby terminating exposure by the shutter return spring  158 . As the hammer  152  moves to its upward position, a cam  214  carried thereby engages a strobe fire switch  216  that depends from the strobe board for firing the strobe during the time that the shutter allows scene light to the film plane through the aperture  156 . It will be appreciated that the hammer  152  remains in its upward position until it is recocked. 
     FIGS. 24,  25 ,  26 A &amp;  26 B illustrate that the cam  214  on the hammer drives the detent arm  174  out of engagement with a respective one of the notches  178   a-c  generally simultaneously as the strobe fire switch is closed (FIGS. 26A,  26 B). However, the slide  122  remains stationary because of the clasping arm  209  retaining the slide in place until released by the operator in a manner to be described. 
     FIGS. 27 and 28 illustrate release of the clasping arm  209  upon release of the shutter button  36  by the operator, thereby freeing the slide to return to the original position under the urging of the clasp spring  166 . Because of a spring (not shown) the shutter link  122  is rotated back to its original position about axis  127  upon release of operator pressure. As this occurs, the cam  128  moves downwardly. It will be realized that an arm  166   a  of the clasp spring  166  engages the arm  204  portion beyond the axis  206  and retains engagement with the cam  128  such that as the cam is rotated the arm  209  is thereby rotated in a counterclockwise direction to remove the distal end  208  from one of the notches  210   a . Owing to the clasp spring portion  166   b  engaging the slide  122 , the latter is returned automatically to the opposite end of the slot whereby the button engages the retainer housing to retain the slide in its original “off” condition (FIGS. 29 &amp; 30) 
     FIG. 31 illustrates a bottom view of the aperture selector slide  122  which includes a main slide portion  122   a  that is interconnected to and relatively movable with respect to a stop element  122   b  by virtue of a spring  123  for allowing the slide portion and the stop element to mfove relative to each other for purposes made apparent. It will be appreciated that the notches are generally aligned in both the main slide portion and the stop element. In this embodiment, the clasp engages the notches in the stop element  122   b  and not necessarily the main slide portion  122   a ; wherein the stop element is actually spring biased by the clasp spring  166  (not shown). Because of this construction and arrangement, a user can easily and reliably manually return the aperture slide  122  to its original or “off” position; after the slide has been moved to one of the aperture setting conditions. In particular, when the user moves the main portion  122   a  its notches will move relative the stop element that has received in detenting relationship the clasp. Owing to the relative movement the notches of the main portion will force the clasp from the notches of the stop element thereby allowing the user to return the slide to its original position if the operator decides not to take a picture. 
     It will be appreciated that changes may be made in the above structure and process without departing from the scope of the invention described herein. It is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted in an illustrative and not in a limiting sense. Thus, other alternatives and modifications will now become apparent without departing from the spirit and scope of the invention.