Abstract: A light-shielding door of a film cassette has a pair of notches or indentations that mate with film support rails of a camera to facilitate movement of a leading end of a filmstrip from the film cassette onto the film support rails when the light-shielding door is open.

Abstract: A camera viewfinder comprises a viewfinder window defining a viewing field, and a masking device movable to position respective mask openings having different aspect ratios over the viewfinder window to vary the viewing field. The masking device includes a pair of separate independent masks, each of which has one of the mask openings and is movable relative to the other over the viewfinder window from respective locations at opposite sides of the viewfinder window.

Abstract: An element has been prepared which is useful for the detection of nucleic acids in various formats. The element has a sealable support on which is disposed a nucleic acid reagent composition. The composition is a mixture of a nucleic acid reagent composed of polymeric particles to which an oligonucleotide is covalently attached. The particles are prepared from a first polymer having a glass transition temperature of at least about 70.degree. C. and have an average diameter of from about 0.1 to about 3 micrometers. The reagent is adhered to the support using a water insoluble adhesive comprising a second polymer which has a glass transition temperature which is at least about 30.degree. C. less than the glass transition temperature of the first polymer. The adhesive is present in the composition at from about 1 to about 20 weight percent. This element provides high sensitivity and low background in hybridization and other nucleic acid assays.

Abstract: A processing rack for holding a plurality of exposed film cartridges from which the respective filmstrips of each cartridge may be unwound to provide full extension thereof to facilitate processing and wound back into the cartridges by selective operation of a reversible drive mechanism that engages the spool of each film cartridge. The rack comprises a plurality of cartridge engaging clamps and elongated guide rods for receiving the respective plurality of cartridges in driving relation with the drive mechanism for unwinding and winding the respective filmstrips from and into each such cartridge. The cartridge engaging clamps are also loosely attached to respective weighted clips which engage the leading end of each of the filmstrips as each such leading end is unwound from the cartridge and are released by thrust forces applied by the leading ends of the filmstrips as they are unwound.

Abstract: A film cassette comprises light blocking means supported for movement to a light blocking position for preventing ambient light from entering the cassette interior and to a non-blocking position. The light blocking means has a cavity for receiving a driver element in driving engagement to allow the driver element to move the light blocking means from its light blocking position to its non-blocking position. A locking pawl protrudes into the cavity to secure the light blocking means in its light blocking position and is adapted to be displaced from the cavity to release the light blocking means when the driver element is received in the cavity.

Abstract: A film cassette comprises a light-shielding door for preventing ambient light from entering the cassette interior, a film spool supported for rotation in film unwinding and film winding directions, and a locking device supported for movement into engagement with the spool to secure the spool and out of engagement with the spool to release the spool. According to the invention, the door is supported for closing movement to prevent ambient light from entering the cassette interior and for opening movement, and includes a cam for moving the locking device into engagement with the spool responsive to closing movement of the door. Also, the locking device is resilient to permit it to be temporarily deformed should it be obstructed from being moved by the cam to engage the spool and the light-shielding door is forcibly closed, or should it be engaging the spool and the spool is forcibly rotated in the film unwinding and winding directions.

Abstract: A rotatable film spool comprises a bar-coded disk with a bar code symbol consisting of a sequence of lesser and greater photo reflective elements having various widths. According to the invention, the lesser photo reflective elements are respective cut-outs in the disk and the greater photo reflective elements are respective flat segments of the disk between adjacent pairs of the cut-outs. By making the lesser photo reflective elements of the bar code symbol respective cut-outs in the disk and the greater photo reflective elements respective flat segments of the disk between adjacent pairs of the cut-outs, it is generally assured that the bar code symbol will be critically located because the various elements are an integral part of the disk.

Abstract: In a film cassette, a spool core about which a filmstrip is coiled is rotated in an unwinding direction to thrust a leading end portion of the filmstrip from inside to outside the cassette. The filmstrip has a trailing or inner end portion with a hole in it. The spool core includes a double-hook piece in the hole having a shorter hook and a longer hook. The shorter hook projects from the hole in the unwinding direction to slightly overlie the trailing end portion to engage the trailing end portion for pushing the filmstrip off the spool core to thrust the leading end portion outside the cassette when the spool core is rotated in the unwinding direction, but which will exit the hole as the trailing end portion begins to separate from the spool core.

Abstract: A film cassette adapted to be opened and closed comprises a film spool supported for rotation, and a lock for inhibiting rotation of the film spool when the cassette is closed and allowing the film spool to rotate when the cassette is opened. According to the invention, a retainer keeps the lock in place to make it inhibit rotation of the film spool when the cassette is opened, but allows the film spool to be initially forcibly rotated to move the lock out of place to then allow the film spool to be freely rotated. Thus, the film spool must be rotated to discontinue the affect of the lock after the cassette is opened.

Abstract: A film cartridge has ah interior spring that first engages the leader of a filmstrip as the leader is initially wound into the cartridge housing and then is distorted from its original shape by further movement of the leader into the housing. When a door connected to the cartridge housing is closed, the spring is maintained distorted in engagement with the leader,opening the door frees the spring, allowing the spring to propel the leader from the cartridge housing by recovering its original shape.

Abstract: A film cassette comprises a spool core supported for rotation in an unwinding direction about an axis, a filmstrip coiled about the spool core to form a film roll, and annular constraining means supported for rotation about the axis of the spool core but inclined with respect to the axis to position the constraining means partially encircling an outermost convolution of the film roll to confine the outermost convolution and partially not encircling the outermost convolution to allow a leading end of the film roll to escape confinement of the outermost convolution when the spool core is rotated in the unwinding direction. The spool core and the annular constraining means include respective engagement means for engaging when the spool core is rotated in the unwinding direction, to make the constraining means rotate with the spool core in the same direction.

Abstract: A photographic film cassette comprising a housing with a hinged lid thrusts film therefrom during the film threading process. The cassette comprises a rotatable film spool concentrically positioned in a housing, within and adjacent to a rotatable, outwardly convex panel member having end plates with camming structure thereon. Corresponding cam followers are located on the interior of the lid, and when the panel member is rotated by a drive spindle accessible to the member through an opening in an end of the housing, the member rotates, camming the lid onto an open position. Film engaged to the member's outer surface by a detent projecting from the surface through a perforation in the film is thrust out of the cassette into engagement with the camera's film transport mechanism. During rewinding, a drive spindle accessible to the spool through the housing's end opening rewinds the film until the perforation is sensed by camera sensing means.

Abstract: A film cassette comprises a cassette shell and a film spool rotatably supported inside the shell. The spool has one end accessible from outside the shell for engagement to rotate the spool. An end cap is sized and shaped to cover the one end of the spool and can be removed from the shell to uncover the one end by pushing against a lip-like portion of the end cap that protrudes from the shell. A tamper-proof label is affixed to the shell and the end cap which is torn along a series of perforations when the end cap is separated from the shell.

Abstract: In a film cartridge, a shell-like enclosure and a lid are latchingly engaged when the lid is closed, to hold the lid closed, and are latchingly engaged when the lid is opened part way to allow film movement in and out of the enclosure, to prevent the lid from being opened farther. The enclosure and the lid can be disengaged to permit the lid to be opened farther or to be closed.

Abstract: In a film cassette, a film stripper is located relative to a film egress passageway to be received between the film leader and the next inward convolution of a film roll to direct the film leader into the passageway responsive to rotation of the film roll in an unwinding direction. According to the invention, the stripper is united with a light blocking device for movement, when the light blocking device is moved to a light blocking position relative to the passageway, to a non-stripping position out of reach of the film roll to prevent receipt of the stripper between the film leader and the next inward convolution and for movement, when the light blocking device is moved to a non-blocking position relative to the passageway, to a stripping position within reach of the film roll to allow receipt of the stripper between the film leader and the next inward convolution.

Abstract: In a film cartridge, a spool hub has a coaxial cavity in one end portion. A cartridge housing for the spool hub has a hole in one end wall that is aligned with the cavity to permit access to the cavity through the hole. A hermetic plug is sized to fit tightly in the hole to act as an airtight seal for the hole, but is sufficiently compliant to permit it to be forcibly pushed intact from the hole into the cavity to provide a visible indication that the film cartridge has been used.

Abstract: In a film cassette, a flange has a central opening into which a spool core for a filmstrip extends to allow rotation of the spool core relative to the flange in film unwinding and film winding directions. According to the invention, a locking pawl supported on a resilient cantilever of the flange biases the locking pawl into the central opening to move from the periphery of the spool core into a cut-out in the spool core to engage with the spool core when the spool core is rotated relative to the flange in the unwinding direction and to allow the locking pawl to move out of the cut-out to disengage the spool core when the spool core is rotated relative to the flange in the winding direction.

Abstract: In a film cassette, a light blocking device is supported for movement to a light blocking position for preventing ambient light from entering a cassette shell and to a non-blocking position, and a separate cassette element such as a film spool is supported for movement to use the film cassette. According to the invention, locking apparatus for normally engaging the cassette element to prevent movement of the cassette element is coupled with the light blocking device for movement, when the light blocking device is moved to its non-blocking position, to a non-locking position disengaged from the cassette element to allow movement of the cassette element. Thus, the film cassette cannot be used unless the light blocking device is in its non-blocking position.

Abstract: A test device comprising beads with a reagent attached, the beads being physically fused to a support. The support includes a material selected to have a melting temperature significantly lower than that of the beads. Polyehtylene is a preferred example of such a material.