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Description  |
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CROSS-REFERENCE TO RELATED APPLICATION
This application is related to U.S. Ser. No. 08/388,783, entitled "CAMERA
WITH MULTI-FORMAT SELECTION", filed Feb. 15, 1995 by Stanley W.
Stephenson, Dennis R. Zander, and Harold J. Barrett
FIELD OF THE INVENTION
The invention relates to photography and more particularly relates to
cameras intended for daylight or bright illumination which are capable of
indicating the format of photographs in one or more formats (pseudo
photography formats).
BACKGROUND OF THE INVENTION
Pseudo photography involves masking the viewfinder of a camera so that the
user of the camera sees the particular picture which he wants printed,
whether it be full frame (normal), telephoto or panoramic in nature, the
latter being of course a type of pseudo wide angle photography. By
suitably identifying on the film with respect to each exposure frame the
particular viewfinder mask used in the exposure (encoding), the printer
can determine how to mask the print or how to mask the negative when
printing from the negative.
U.S. Pat. No. 4,973,997 discloses a camera that makes use of ambient light
directed through light pipes to expose spots on the film to indicate
normal, telephoto or panoramic print formats. Such use of ambient light
can result in unreliability or underexposure under certain conditions.
It would thus be desirable to provide a camera that can expose one or more
spots for indicating film format which does not use ambient light and does
not use a complex circuit.
SUMMARY OF THE INVENTION
The invention is defined by the claims. The invention, in its broader
aspects, provides a camera for use with photographic film. The camera has
a body and an exposure system disposed in the body for exposing the film
on a frame-by-frame basis. The exposure system includes an exposure
opening and a shutter mechanism. The shutter mechanism is momentarily
displaceable from a closed state to an open state. A light emitting diode
is disposed in the body for directly illuminating one or more positions on
the film. Momentarily closeable, normally open contacts are mounted in the
body. The contacts are closed for a time period of from about 0.05
milliseconds to about 10 milliseconds, or preferably from about 0.05
milliseconds to about 2 milliseconds, when the shutter mechanism is in the
open state. A circuit directly connects the battery unit to the light
emitting diode when the contacts are closed. During contact closure, a
battery unit powers the light emitting diode at a current level beyond
continuous use operating limits of the light emitting diode.
It is an advantageous effect of at least some of the embodiments of the
invention that a camera is provided that can expose one or more spots for
indicating film format which does not use ambient light and does not use a
complex circuit.
BRIEF DESCRIPTION OF THE FIGURES
The above-mentioned and other features and objects of this invention and
the manner of attaining them will become more apparent and the invention
itself will be better understood by reference to the following description
of an embodiment of the invention taken in conjunction with the
accompanying figures wherein:
FIG. 1 is a semi-diagrammatical rear view of the interior of the camera of
the invention. For clarity, part of the film is cut-away and the format
selector and conductors of the electrical circuit are not shown. The
shutter is illustrated in an open state by dashed lines and in a closed
state by solid lines. The exposure opening is indicated by a dashed line.
The batteries are shown in one alternative location by solid lines and in
another alternative location by dashed lines. Some dimensions are
exaggerated for clarity.
FIG. 2 is a diagrammatical view of the optical writing system of the
invention as incorporated in the camera of FIG. 1. The area of
illumination of the light emitting diode is indicated by dashed lines.
FIGS. 3a, 3b, and 3c are diagrammatical views of the format selector of the
camera of FIG. 1, shown in positions for encoding optical data indicating
three formats. The position of the viewfinder is indicated by dashed
lines. Indicia corresponding to the three formats are symbolized by the
letters: "A", "B", "C".
FIG. 4 is a semi-diagrammatical top view of the interior of the camera of
FIG. 1. Additional alternative positions for the batteries are indicated
by dashed lines. For clarity, various components are not shown and some
dimensions are exaggerated.
FIG. 5 is a diagrammatical view of the method of the invention.
DESCRIPTION OF PARTICULAR EMBODIMENTS
Referring now to FIGS. 1 and 2, the optical writing system 10 of the
invention includes a photographic film holder 12 for holding photographic
film 13; a light emitting diode 14; electrical contacts 16; a battery unit
18; and conductors 20 to complete the circuit between the light emitting
diode 14, contacts 16, and battery unit 18. In a preferred embodiment of
the invention, the optical writing system 10 is incorporated as part of
the reusable or single use camera 22 of the invention; however, the
optical writing system 10 can be utilized as an independent article, for
example, to optically mark the film leader of a roll of film; or can be
utilized as a component of other articles that utilize photographic film,
such as, photographic film-type radiation monitor badges. The following
discussion is primarily directed to cameras of the invention, but it will
be understood that similar characteristics could be provided in a
non-camera optical writing system of the invention.
Referring now to FIGS. 1-4, in the camera 22 of the invention the film
holder of the optical writing system is a camera body 12a. Mounted in the
body 12a is an exposure system 24 that receives light from an object to be
photographed and directs that light to the film 13.
The camera of the invention is not limited as to use of any particular type
of camera body; however, the invention is particularly advantageous for
small cameras; since, apart from the film holder, all the components of
the optical writing system of the invention are very small. Thus a
desirable body for a camera of the invention minimizes dead space, that
is, minimizes unused empty spaces within the assembled camera. Since the
non-film holding components of the optical writing system are so small; a
suitable body can be designed by first accomodating larger components,
then making modifications for improved aesthetics and reduced
manufacturing costs, then attempting to fit the optical writing system
within any dead spaces provided as artifacts of the earlier steps of the
design process and finally considering modifying the design to accomodate
the optical writing system only if existing dead spaces are inadequate.
Within these desired limitations, the body 12a of the camera 22 can take a
wide variety of forms. For example, the figures are generally directed to
cameras 22 having clamshell bodies, having all or most components attached
to an internal frame member or carcass 26, which is covered by clamshell
shaped front and rear covers 28,30. This type of camera body is commonly
used in single use cameras. Another body type commonly used in small
cameras has a major front portion with or without an inserted carcass
beating the operative components and a flat or L-shaped back panel.
The exposure system 24 is mounted in the body 12a and directs light from
the object to be photographed to a frame of the film 13. The exposure
system 24 can be limited to use with a single frame of film, but
preferably includes a film transport 32 to move the film on a
frame-by-frame basis, i.e., one frame at a time, through an exposure
chamber 34. A very wide variety of film transports are well known to those
of skill in the art. The film transport 32 can be manual or motor driven
and can include any of a variety of known components such as advance
levers, thumbwheels, rewinds, sprockets, gear trains, sliding pawls,
clutches, and motors in any of a variety of combinations. FIGS. 1 and 4
diagrammatically illustrate a type of film transport commonly found in
single use cameras. Unexposed film in the form of a scroll around a spool
or a spool-less roll 36 is advanced from an unexposed film chamber 38 back
into a film canister or patrone 40 resting in a second chamber 42. This
film transport 32 lacks any components to rewind the film after exposure,
since rewinding is unnecessary. The film transport 32 can include a number
of other features useful in both moving the film and positioning the film
relative to the exposure chamber 34. For example, the film transport can
include a member that interacts with the active light lock of an Advanced
photo System.sup.198 (APS.TM.) cartridge. The body 12a can include
features interactive with the film transport 32 to help maintain the
configuration of the film 13 relative to the film exposure chamber 34,
such as a shaped back member or resilient film support (not shown).
The invention is not limited to use of any particular type of film or film
magazine or cartridge. For example, the figures illustrate sprocketed film
and an elliptical film cartridge; but the invention can also utilize
non-sprocketed film and film in other types of cartridge, such as 135 or
110 type cartridges.
The exposure system 24 includes an exposure opening 44 and a shutter
mechanism 46, which is momentarily displaceable from a closed state 48, in
which the exposure opening is blocked, and an open state 50 in which light
from an object to be photographed propagates through the exposure opening
44. The shutter mechanism 46 includes one or more shutter elements 52 and
a shutter actuator 54. The contacts 16 are positioned such that the
movement of the shutter mechanism 46 causes the contacts 16 to close. The
shutter mechanism 46 provides for relatively rapid shutter movement such
that the contacts 16 are closed for a time period of from about 0.05
milliseconds to about 10 milliseconds, or preferably from about 0.05
milliseconds to about 2 milliseconds. Suitable shutter mechanism for this
purpose are well known to those of skill in the art. For example, most
conventional single use camera mechanisms provide both shutters of
suitable speed and appropriately positioned contacts which could also be
used in camera 22. (The contacts on those cameras are used as momentarily
closing, normally open flash synchronization contacts.) On some cameras,
such as the Kodak pocket Funsaver.TM., marketed by Eastman Kodak Company,
Rochester, N.Y.; one of the flash synchronization contacts and a shutter
blade are parts of a unitary metal leaf. Such shutter mechanisms and
contacts are also useful for camera 22.
A currently preferred shutter mechanism 46 is disclosed in U.S. Pat. No.
4,896,178, which is hereby incorporated herein by reference. In this
mechanism, as shown semi-diagrammatically in FIGS. 1 and 4, the shutter
mechanism 46 has a shutter element 52 that is actuated by a shutter
actuator or high energy lever 54 driven by a spring (not shown) and is
connected to a shutter release 55.
The shutter mechanisms above-discussed utilize a single leaf type shutter.
With this type of shutter mechanism, there is a single closed position and
the open state represents a continuum of shutter positions from open to
closed. The invention is not limited to single leaf shutter mechanisms.
The shutter mechanism can have a multiple element shutter, in which case,
the closed state can represent multiple closed positions of the various
elements.
In addition to the exposure opening 44 and shutter mechanism 46, the
exposure system 24 can also include any of a wide variety of features
known to those of skill in the art for these purposes. The exposure system
24 can include any of a wide variety of lens systems 56. The exposure
opening 44 can be provided as a part of a number of different components,
such as a lens support (not shown) or baffle 58. Similarly the shutter
mechanism 46 can also include additional features. For example, the
shutter mechanism 46 can be integrated with the film transport 32 so that
a single winding mechanism (not separately illustrated) can advance and
meter the film and cock the shutter mechanism.
The light emitting diode 14 is disposed in the body 12a so as to directly
illuminate one or more positions on the frame of film 13 in the exposure
chamber 34. The illumination of the film by the fight emitting diode 14
results in a latent image segment disposed in a known, predetermined
location on the film relative to a respective film frame (and the latent
image of the subject matter imaged by that film frame). The image segment
provided in a currently preferred embodiment of the camera of the
invention is an encoded format designation in the form of one dot, two
dots, or no dots. In this embodiment, the image segment is offset on the
film from the fill frame.
The color of the light emitting diode 14 is not critical, however, in
practical application, red light emitting diodes are lowest cost for
visible light sensitive films. Red light emitting diodes are also
convenient for use with APS film, since APS fill processing equipment
looks for red densities (approximately 650 nm).
The figures illustrate a light emitting diode 14 that is attached to an LED
holder 60. The LED holder 60 can be mounted to or formed as an integral
part of the camera carcass 26. It is desirable that the LED holder 60 be
small so that the light emitting diode 14 is close to the film 13. A
suitable separation of film and light emitting diode is about 0.25 inches.
The LED holder 60 includes holes 62 that define the shapes of the dots
imaged on the fill. A blocking member 64, discussed more fully below, is
mounted so as to be movable between the light emitting diode 60 or LED
holder 62 and the film 13.
The invention is not limited to the formation of dot patterns or the like
on the film. The holder can define indicia or a small visual image. For
example, in a non-camera optical writing system of the invention, the
holder could define identification information to be written to a
filmchip. Similarly, the holder can be dispensed with and be replaced by a
blocking member that blocks or defines one or more images depending upon
its position.
The contacts 16 are mounted in the body 12a and are positioned so as to be
operated by the shutter mechanism 46 and momentarily move from an open
condition 66 to a closed condition 68. In the embodiment shown in the
figures, the contacts 16 are struck by the shutter element 52 when the
shutter element 52 moves from the closed state 48 to the open state 50 and
then back to the closed state 48. The contacts 16 are momentarily
closeable, normally open. Suitable contacts 16 are made the same as flash
synchronization contacts commonly used in single use cameras. Such
contacts are generally operated directly by movement of a leaf shutter and
commonly consist of a resilient conductor that is pushed by the shutter
against a second conductor. An example of such contacts are two copper
leaves having a thickness of from about 0.002 inches to about 0.005
inches. The resilient conductor or conductors also acts as a spring for
the shutter to help the shutter more quickly reverse direction.
As noted above, the displacement of the shutter mechanism 46 to the open
state 50 causes the contacts 16 to be closed for a time period of from
about 0.05 milliseconds to about 10 milliseconds, preferably the contacts
16 close for from about 0.05 milliseconds to about 2 milliseconds. In a
more preferred embodiment of the invention, the contacts 16 close for
about 1 millisecond.
The battery unit 18 is selected to power the light emitting diode 14 at a
current level beyond continuous use operating limits of the light emitting
diode 14. A suitable light emitting diode is rated for continuous use at
20 milliamps at 1.5 volts. It is desirable to use a battery unit 18 and
contact closing time that result in a current level of less than about 50
times the rated continuous use operating amperage limit of the light
emitting diode 14. It is even more desirable that the battery unit 18 and
contact time result in an overamperage of no more than about 10 times the
rated capacity. The overamperage must, however, be sufficient to cause the
light emitting diode 14 to operate at the voltage supplied by the battery
unit 18 and provide sufficient light to expose the film. A suitable
exposure, for example, provides a density at a monitored wavelength that
is at least 0.5 times greater than the base density (D-rain) of the film
as measured by a Kodak Model 2 Densitometer, marketed by Eastman Kodak
Company, Rochester, N.Y. The battery unit 18 has one or more batteries 70
and can include a resistor in series with a battery if necessary. Small
batteries are desirable for the battery unit 18, such as a pair of nominal
1.5 volt button cells in series. The button cells are very small and can
be placed together electrode-to-electrode or can be arranged in some other
manner and be electrically connected together by a conductor. The size of
the button cells is such that when the cells are placed end to end, the
maximum dimension of the battery unit 18 is equal to or less than the
diameter of the film scroll 36 of unexposed film or, in a single use
camera, less than the diameter of a substantially cylindrical film scroll
space 38 for storage of unexposed photographic film defined in the body
12a.
A particularly suitable button cell for this purpose is a type 389 A cell,
which is 0.45 inches in diameter and 0.112 inches thick. Two of these
cells in series provide a battery unit 18 that requires no additional
resistor. A battery unit having two type 389 A cells in series when used
with a light emitting diode rated for continuous use at 20 milliamps and
contacts 16 that closed for about 1 millisecond was tested and
successfully provided spots at about 0.8 density above base density of the
film, measured as above indicated. The light emitting diode used required
greater than 1.5 volts of bias potential to emit light. Two 389 A cells
were used to raise the bias voltage above 1.5 volts to about 3.0 volts.
The light emitting diode was subjected to 300 activations and continued to
glow at about the same intensity.
The electrical circuit of the optical writing system is completed by
conductors 20 connecting the light emitting diode 14, contacts 16, and
battery unit 18. The circuit can include other electrical components, that
do not significantly modify the operation of the circuit, however, this is
generally not desirable for reasons of both space and expense. The camera
of the invention could include separate flash circuitry, however, this
would greatly detract from size and low cost advantages otherwise
available.
The camera of the invention can be configured such that the light emitting
diode 14 marks each frame with the same dot pattern. With APS film or the
like, photofinishing equipment would read the dot pattern and process each
frame with the same picture format, for example, panoramic format. The
camera of the invention can also be provided with means for selectively
varying the illumination of the film by the light emitting diode 14. For
example, APS film can be selectively encoded with dot patterns
corresponding to two or more formats. In these embodiments of the
invention, a blocking member 64 is selectively interposable between the
film and the light emitting diode 14. FIGS. 3a -3c illustrate an
embodiment of the invention in which a film format selector 72 shaped like
a backwards letter "Z"has an arm 74 connecting a blocking member 64 to a
visible format indicator 76. The selector 72 has a handle (not shown) that
can be moved back and forth by a user to slide the selector 72 relative to
holes 62 in the LED holder 60 and indicia 78 visible through a viewfinder
80. The number of holes 62 covered, and spots produced on the film
corresponds to a different film format, as indicated by respective indicia
78 in the viewfinder 80, symbolized: "A", "B", "C". The visible format
indicator 76 could also another type of viewfinder mask in which areas of
the viewfinder inappropriate to a particular format are at least partially
obscured when the mask is moved into that position. A suitable viewfinder
mask of this type is disclosed in U.S. Pat. No. 4,583,831, which is
incorporated herein by reference. The visible format indicator could also
be as simple as a pointer located so as to point toward appropriate
indicia on the camera body.
As previously indicated, the camera of the invention is particularly
suitable as a single use camera lacking a rewind mechanism. In a currently
preferred such camera, the body 12a includes front and rear covers 28,30
and a recyclable frame member or carcass 26 and the exposure system 24,
light emitting diode 14, contacts 16, battery unit 18, and conductors 20
of the circuit are mounted to the frame member 26. This is a practical
approach for recycling of single use camera, since front and rear covers
are commonly damaged and are more suitable for use as feedstocks than for
direct recycling. Unlike previous single use cameras, in which batteries
are replaced prior to recycling, in the camera of the invention, the
battery 70 can be recycled without replacement, without significant risk
of insufficient battery power during the lifetime of the recycled camera.
To prevent inadvertent removal of the battery unit 18, it is desirable
that the battery or batteries 70 be permanently mounted in the frame
member 26. It is desirable that the frame member 26 be marked to limit use
to a predetermined number of recycling cycles. Such marking of recycled
cameras is known and is not difficult.
In the recycling method of the invention, exposed film 82 is first removed
(84) from the used camera 22a (illustrated as being damaged). Components
having operational parameters below nominal values are then discarded
(86). A frame assembly 88 including the carcass, light emitting diode, and
at least one original battery 70, or preferably, a pair of permanently
mounted button cell batteries, is retained (90). The frame assembly 88 is
preferably marked (92) to indicate another reuse cycle. Replacement parts
are provided (96). Fresh film 94 is inserted (98) and the recycled camera
22b is ready for reuse.
While specific embodiments of the invention have been shown and described
herein for purposes of illustration, the protection afforded by any patent
which may issue upon this application is not strictly limited to a
disclosed embodiment; but rather extends to all modifications and
arrangements which fallfairly within the scope of the claims which are
appended hereto:
parts list
optical writing system 10
photographic film holder 12
camera body 12a
photographic film 13
light emitting diode 14
contacts 16
battery unit 18
conductors 20
camera 22
exposure system 24
frame member or carcass 26
front and rear covers 28,30
film transport 32
exposure chamber 34
roll 36
film chamber 38
canister 40
second film chamber 42
exposure opening 44
shutter mechanism 46
closed state 48
open state 50
shutter element 52
shutter actuator 54
shutter release 55
lens system 56
baffle 58
LED holder 60
holes 62
blocking member 64
open condition 66
closed condition 68
battery 70
selector 72
arm 74
indicator 76
indicia 78
viewfinder 80
exposed film 82
removal step (84)
discard step (86)
frame assembly 88
retaining step (90)
marking step (92)
fresh film 94
providing step (96)
inserting step (98)
* * * * *
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