U.S. patent application number 11/002004 was filed with the patent office on 2005-06-16 for method and apparatus to pre-scan and pre-treat film for improved digital film processing handling.
Invention is credited to Mooty, George G., Thering, Michael R., Young, Robert S. JR..
Application Number | 20050128474 11/002004 |
Document ID | / |
Family ID | 26869388 |
Filed Date | 2005-06-16 |
United States Patent
Application |
20050128474 |
Kind Code |
A1 |
Young, Robert S. JR. ; et
al. |
June 16, 2005 |
Method and apparatus to pre-scan and pre-treat film for improved
digital film processing handling
Abstract
The present invention provides a method, apparatus and system
that pre-scans and pre-treats film for improved digital film
processing. The apparatus for use with the invention includes,
generally, a sensor for detecting one or more imperfections on the
film and a microprocessor connected to the sensor that determines
the amount and extent of imperfections of the film based on one or
more reference readings. The present invention may also include a
tape dispenser, cleaning rollers, a blower or vacuum to remove
and/or correct any imperfections in the film. One embodiment
includes a cleaning system for a particle removal member which
removes particles from film. The cleaning system is relatively
movable and selectively contactable with the particle removal
member to clean particles from the particle removal member.
Inventors: |
Young, Robert S. JR.;
(Austin, TX) ; Mooty, George G.; (Austin, TX)
; Thering, Michael R.; (Austin, TX) |
Correspondence
Address: |
Mark G. Bocchetti
Patent Legal Staff
Eastman Kodak Company
343 State Street
Rochester
NY
14650-2201
US
|
Family ID: |
26869388 |
Appl. No.: |
11/002004 |
Filed: |
December 2, 2004 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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11002004 |
Dec 2, 2004 |
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09751119 |
Dec 28, 2000 |
|
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6864973 |
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60173648 |
Dec 30, 1999 |
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Current U.S.
Class: |
356/239.2 |
Current CPC
Class: |
G01N 21/8916
20130101 |
Class at
Publication: |
356/239.2 |
International
Class: |
G01N 021/00 |
Claims
1-33. (canceled)
34. An apparatus for cleaning film in a film processing system,
comprising: a particle removal member configured to remove
particles from film; a cleaning system automatically movable
between a contacting position and a non-contacting position,
wherein, in the contacting position, the cleaning system is
configured to contact the particle removal member and remove
particles therefrom, wherein the cleaning system is configured to
automatically move from the non-contacting position to the
contacting position at a predetermined time.
35. The apparatus as recited in claim 34, wherein the particle
removal member comprises a particle removal roller adapted to
rotate as film is moved past the roller.
36. The apparatus as recited in claim 34, wherein the particle
removal member comprises an adhesive surface adapted for removing
particles from the film as the film is moved past the member.
37. The apparatus as recited in claim 34, wherein the cleaning
system comprises: an adhesive tape; and a cleaning member
comprising a contact roller in contact with the tape and movable
between the contacting position and the non-contacting
position.
38. The apparatus as recited in claim 34, wherein the cleaning
system comprises: a cleaning member movable between the contacting
position and the non-contacting position; and a controller
configured to cause the cleaning member to move between the
contacting position and the non-contacting position at the
predetermined time.
39. The apparatus as recited in claim 34, wherein the particle
removal member comprises a roller and the predetermined time
comprises a predetermined number of rotations of the roller.
40. An apparatus for cleaning film in a film processing system,
comprising: a film transport system for moving film through a
predetermined path: a particle removal member configured to contact
film and remove particles from the film as the film is moved
through the predetermined path; and a cleaning system configured to
remove particles from the particle removal member, the cleaning
system and the particle removal member being relatively movable so
as to be selectively contactable with respect to each other, the
cleaning system having a particle attraction surface operative to
remove particles from the particle removal member when the cleaning
system is in contact with the particle removal member.
41. The apparatus as recited in claim 40, wherein the cleaning
system comprises: a disposable adhesive tape having the particle
attraction surface; and a cleaning member in contact with the
tape.
42. The apparatus as recited in claim 41, further comprising: a
tape transport system configured to move the tape over the cleaning
member.
43. The apparatus as recited in claim 40, wherein the particle
removal member comprises a particle take-off roller, and wherein
the cleaning system includes a contact roller relatively movable
with respect to the particle take-off roller.
44. The apparatus as recited in claim 43, wherein the cleaning
system further comprises: a disposable adhesive tape in contact
with the contact roller and relatively movable with respect to the
contact roller.
45. The apparatus as recited in claim 40, wherein the cleaning
system comprises a cleaning member; and a controller configured to
cause the cleaning member to move relative to the particle removal
member at a predetermined time.
46. The apparatus as recited in claim 45, wherein the particle
removal member comprises a roller and the predetermined time
comprises a predetermined number of rotations of the roller.
47. An apparatus for cleaning film in a film processing system,
comprising: a particle removal member configured to remove
particles from film; a cleaning system comprising: a disposable
adhesive tape; a cleaning member in contact with the tape and
movable between a contacting position and a non-contacting
position, wherein, in the contacting position, the cleaning member
is configured to place the tape in contact the particle removal
member such that the tape removes particles therefrom; and a tape
transport system for movement of the tape across the cleaning
member.
48. The apparatus as recited in claim 47, wherein the cleaning
member comprises a contact roller and the particle removal member
comprises a particle take-off roller.
49. The apparatus as recited in claim 47, wherein the cleaning
system further comprises: a controller configured to cause the
cleaning member to move between the contacting position and the
non-contacting position at predetermined times.
Description
[0001] This application claims the benefit of U.S. Provisional
Application No. 60/173,648, filed Dec. 30, 1999, the entire
disclosure of which is hereby incorporated herein by reference.
TECHNICAL FIELD
[0002] The present invention relates generally to the field of
digital film processing, and more particularly, to an apparatus and
method for pre-screening and pre-treating film that is amenable to
digital film processing.
BACKGROUND OF THE INVENTION
[0003] Standard color photographic negative film that is widely
used in still cameras today is designed and manufactured to contain
three superimposed, semi-independent color sensing layers. Spectral
sensitivity curves for photographic negative film show the typical
response of the three layers of photographic film over the visible
light spectrum; assuming equal radiated power at each wavelength.
In particular, it is known that the top layer responds primarily to
light of short wavelength (blue light), the middle layer responds
primarily to light of medium wavelength (green light) and the
bottom layer responds to light of long wavelength (red light). When
film with these types of spectral sensitivities is exposed to
visible light, each spot on the film records the amount of blue,
green and red light, or flux. Incident flux creates what is
referred to as the latent image.
[0004] In conventional color photographic development systems, the
exposed film is chemically processed to produce dyes in the three
layers with color densities directly proportional to the blue,
green, and red spectral exposures that were recorded in the latent
image. Yellow dye is produced in the top layer, magenta dye in the
middle layer, and cyan dye in the bottom layer. Through a separate
conventional process, positive photographic images may then be
electronically scanned to produce a digital image.
[0005] Conventional electronic scanning of developed photographic
negative film to produce digital images is done by passing visible
light through the developed negative and using filters with
appropriate spectral responsivities to detect, at each location on
the film, the densities of the yellow, magenta and cyan dyes in the
photographic negative. The density values detected in this way are
indirect measures of the blue, green and red light that initially
exposed each location on the film. These measured density values
constitute three values used as the blue, green and red values for
each corresponding location, or pixel, in the digital image.
Further processing of these pixel values is often performed to
produce a digital image that accurately reproduces the original
scene and that is pleasing to the human eye.
[0006] Image enhancement has been the subject of a large body of
film processing technology. A common feature of all digital film
processing technology is that the film to be scanned must be
relatively flat during the optical scan. Furthermore, the optical
scan best occurs using a relatively uniform velocity during the
scan period. Small imperfections in the film, such as tearing,
creases, scratches, foreign objects and fluids decrease the
efficacy of the digital scan. Large imperfections make digital film
processing and conventional scanning very difficult.
[0007] Large imperfections to the film surface, such as broken,
ripped or torn sprocket holes, are encountered frequently during
automated film processing. In film processing using chemical
development tanks, tears to the sprocket holes are generally not an
issue because they are not used to transfer the film from tank to
tank. For example, torn sprocket holes occur when the user, or in
the case of automated cameras, the auto-drive advances the film too
far, breaking one or more of the sprocket holes.
[0008] In addition to large imperfections, such as sprocket hole
breakage, other imperfections may occur when foreign objects, such
as water, particles (e.g., dust), and oils contact the film.
Exposure to these foreign objects may even occur while the film is
still in its original canister. Creases in the film are yet another
imperfection that may occur when the film is reverse-wound.
SUMMARY OF THE INVENTION
[0009] The present invention relates to pre-screening and/or
pre-treating film before further chemical processing and scanning.
Presently, conventional systems do not take into consideration of
the special needs of digital film processing ("DFP") techniques and
devices. The present invention can correct, to the extent possible,
film imperfections prior to processing. In at least one embodiment,
imperfections in the film can be identified and then corrected.
[0010] In a particular embodiment, the present invention comprises
an apparatus for use in digital image processing in which the
suitability of a film for DFP is determined prior to scanning. The
apparatus for use with the invention includes, generally, a sensor
for detecting one or more imperfections on the film and a
microprocessor connected to the sensor that determines the amount
and extent of imperfections of the film based on one or more
reference readings. A reference sensor and a memory may be
connected to the microprocessor to provide the reference readings.
The reference sensor readings may be determined by the reference
sensor and stored in the memory for use by the microprocessor. The
reference sensor may be a reflective sensor or a sensor that reads
light that traverses the film, is reflected by the film or
both.
[0011] In a particular embodiment of the invention, the apparatus
may also include a tape dispenser positioned to repair the film if
the imperfection detected by the sensor is a breakage in the film.
For example, the sensor may detect abnormalities in the shape of
the perforations or sprockets on the film. Another imperfection
that may be detected, and in some embodiments corrected, is the
detection of moisture on the film (or even the actual moisture
level). If excessive moisture is detected, as determined in the
comparison of actual and reference measurements, the film is dried
until the moisture level drops below the predetermined acceptable
moisture level. Film may be dried using, for example, a blower, a
vacuum or even rollers that remove moisture mechanically or by
capillary action.
[0012] When the sensor detects foreign objects on the film, these
may be removed using a variety of systems. One such system is the
use of a blower, a vacuum or both to remove the foreign object.
Another system may use one or more rollers that mechanically remove
the foreign object, e.g., tacky rollers. When the sensor detects
one or more foreign objects on the film, the microprocessor
compares the amount of foreign object(s) on the film to reference
levels, and if the level is above a predetermined acceptable
foreign object level, the film is cleaned until the foreign object
level drops below the predetermined acceptable foreign object
level.
[0013] Yet another embodiment of the present invention is a method
of identifying film suitable for digital image processing that
includes the steps of: exposing film to one or more light sources;
detecting the light reflected from the film to measure
imperfections on the film; determining if the imperfections on the
film exceed reference sensor readings; and routing the film based
on the sensor output depending on whether the film is suitable for
digital film processing from film that is not suitable for digital
film processing. The method may also include the steps of:
determining the level of moisture in the film, detecting foreign
objects on the film; and scanning for one or more broken sprockets
on the film edges. Imperfections in the moisture level, the
presence of foreign objects and broken sprockets will lead to
rejection of the film from further digital film processing. The
invention may also include one or more of the following film
imperfection correction systems. Imperfections on the film are
corrected selecting a remedial measure that corrects the
imperfection, for example, where excessive moisture and foreign
objects are detected they are removed. Likewise, if one or more
broken sprockets are detected, they may be repaired using, e.g., a
tape dispenser mechanism prior to digital film processing.
[0014] Other embodiments of the present invention may include
always cleaning the film and then inspecting the film, or
performing the cleaning and inspection steps in an iterative
manner. The results of the inspection may then be reported to an
operator or recorded in some manner. If the film is rejected, it
can be rolled back into the canister or stored in a new canister or
storage device. Moreover, the present invention may report the
specific reasons why the film was rejected and identify where on
the film the problems were detected.
[0015] To clean the film upon detection of imperfections, or as a
standard procedure, a particle removal member can be utilized. In
one embodiment, the particle removal member which can be easily and
efficiently cleaned when a need for cleaning is identified. In
particular, the particle removal member can be periodically cleaned
by a cleaning system which is adapted for removing particles from
the particle removal member. In this embodiment, the cleaning
system and the particle removal member are relatively movable so as
to be selectively contactable with respect to each other. The
cleaning system has a particle adhering surface which is operative
to remove particles from the particle removal member when the
cleaning system is in contact with the particle removal member. The
particle adhering surface can comprise disposable adhesive tape and
a tape transport system can be used to advance the tape across a
cleaning member, such as a roller for example. The cleaning system
can automatically move into contact with the particle removal
member at predetermined times, such as detection of a passage of
time or an amount of usage for example. Other features and
advantages of the present invention shall be apparent to those of
ordinary skill in the art upon reference to the following detailed
description taken in conjunction with the accompanying
drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] The above and further advantages of the invention may be
better understood by referring to the following description in
conjunction with the accompanying drawings in which corresponding
numerals in the different figures refer to corresponding parts in
which:
[0017] FIG. 1 is a perspective view of a scanning device in
accordance with the present invention;
[0018] FIG. 2 is an illustration of a digital film processing
system which uses duplex film scanning in accordance with the
present invention;
[0019] FIG. 3 shows a configuration of a film pre-scan apparatus in
accordance with the present invention;
[0020] FIG. 4 is a flow chart of a method for pre-scanning film in
accordance with the present invention;
[0021] FIG. 5 is a schematic diagram of film cleansing system which
can be used to efficiently clean film prior to digital film
processing;
[0022] FIG. 6 is schematic diagram of the system of FIG. 5,
illustrating a cleaning member in the contacting position for
removal of particles from the particle removal member; and
[0023] FIGS. 7 and 8 are schematic diagrams showing an indexing
system for automatic movement of the cleaning member of FIG. 6
between a contacting and a non-contacting position.
DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS
[0024] While the making and using of various embodiments of the
present invention are discussed herein in terms of a digital film
processing system, it should be appreciated that the present
invention provides many applicable inventive concepts which can be
embodied in a wide variety of specific contexts. For example, the
present invention can be used to pre-scan and pre-treat any strip
of material. The specific embodiments discussed herein are merely
illustrative of specific ways to make and use the invention and do
not delimit the scope of the invention.
[0025] The term "film" is used hereinafter to refer to any
unrestricted length of material. The film may or may not have
aligned and evenly spaced perforations, which are hereinafter
referred to as "sprocket holes." Camera or motion picture film is,
of course, a primary example, but the present invention is not to
be construed to be limited to a film for still camera or even
motion picture film. The film may be a strip of material for other
purposes as well.
[0026] An improved digital film scanning apparatus is shown in FIG.
1. The scanning apparatus 100 operates by converting
electromagnetic radiation from an image to an electronic (digital)
representation of the image. The image being scanned is typically
embodied in a physical form, such as on a photographic media, i.e.,
film, although other media may be used. In general, the
electromagnetic radiation used to convert the image into a
digitized representation is preferably infrared light. The scanning
apparatus 100 generally includes a number of optic sensors 102. The
optic sensors 102 measure the intensity of electromagnetic energy
passing through or reflected by the film 112. The source of
electromagnetic energy is typically a light source 110 which
illuminated the film 112 containing the scene image 104. Radiation
from the source 110 may be diffused or directed by additional
optics such as filters (not shown) and one or more lenses 106
positioned near the sensors 102 and the film 112 in order to
illuminate the images 104 and 108 more uniformly. Furthermore, more
than one source may be used. Source 110 is positioned on the side
of the film 112 opposite the optic sensors 102. This placement
results in sensors 102 detecting radiation emitted from source 110
as it passes through the image 104 on the film 112. Another
radiation source 111 is shown placed on the same side of the film
112 as the sensors 102. When source 111 is activated, sensors 102
detect radiation reflected by the images 104 and 108. This process
of using two sources positioned on opposite sides of the film being
scanned is described in more detail below in conjunction with FIG.
2.
[0027] The optic sensors 102 are generally geometrically positioned
in arrays such that the electromagnetic energy striking each
optical sensor 102 corresponds to a distinct location 114 in the
images 104 and 108. Accordingly, each distinct location 114 in the
scene image 104 corresponds to a distinct location, referred to as
a picture element, or pixel for short, in the scanned, or digitized
image. The image 104 on film 112 is usually sequentially moved, or
scanned, across the optical sensor array 102. The optical sensors
102 are typically housed in a circuit package 116 that is
electrically connected, such as by cable 118, to supporting
electronics for computer data storage and processing, shown
together as computer 120. Computer 120 may then process the
digitized image 105. Alternatively, computer 120 may be replaced
with a microprocessor and cable 118 replaced with an electrical
circuit connection.
[0028] Optical sensors 102 may be manufactured from different
materials and by different processes to detect electromagnetic
radiation in varying parts and bandwidths of the electromagnetic
spectrum. The optical sensor 102 may include a photodetector (not
expressly shown) that produces an electrical signal proportional to
the intensity of electromagnetic energy striking the photodetector.
Accordingly, the photodetector measures the intensity of
electromagnetic radiation attenuated by the image 104 on film
112.
[0029] Turning now to FIG. 2, a conventional color film 112 is
depicted. As previously described, the present invention uses
duplex film scanning that refers to using a front source 216 and a
back source 218 to scan the film 112 with reflected radiation 222
from the front 226 and reflected radiation 224 from the back 228 of
the film 112 and by transmitted radiation 230 and 240 that passes
through all layers of the film 112. While the sources 216, 218 are
generally monochromatic and preferably infrared. The respective
scans, referred to herein as front, back, front-through and
back-through, are further described below.
[0030] In FIG. 2, separate color levels are viewable within the
film 112 during development of the red layer 242, green layer 244
and blue layer 246. Over a clear film base 232 are three layers
242, 244, 246 sensitive separately to red, green and blue light,
respectively. These layers are not physically the colors; rather,
they are sensitive to these colors. In conventional color film
development, the blue sensitive layer 246 would eventually develop
a yellow dye, the green sensitive layer 244 a magenta dye, and the
red sensitive layer 242 a cyan dye.
[0031] During film development, layers 242, 244, and 246 are
opalescent. Dark silver grains 234 developing in the top layer 246,
the blue source layer, are visible from the front 226 of the film,
and slightly visible from the back 228 because of the bulk of the
opalescent emulsion. Similarly, grains 236 in the bottom layer 242,
the red sensitive layer, are visible from the back 228 by reflected
radiation 224, but are much less visible from the front 226. Grains
238 in the middle layer 244, the green sensitive layer, are only
slightly visible to reflected radiation 222, 224 from the front 226
or the back 228. However, they are visible along with those in the
other layers by transmitted radiation 230 and 240. By sensing
radiation reflected from the front 226 and the back 228 as well as
radiation transmitted through the developing film 112 from both the
front 226 and back 228 of the film 112, each pixel for the film 112
yields four measured values, one from each scan, that may be
mathematically processed in a variety of ways to produce the
initial three colors, red, green and blue, closest to the original
scene.
[0032] The front signal records the radiation 222 reflected from
the illumination source 216 in front of the film 112. The set of
front signals for an image is called the front channel. The front
channel principally, but not entirely, records the attenuation in
the radiation from the source 216 due to the silver metal particles
234 in the top-most layer 246, which is the blue recording layer.
There is also some attenuation of the front channel due to silver
metal particles 236, 238 in the red and green layers 242, 244.
[0033] The back signal records the radiation 224 reflected from the
illumination source 218 in back of the film 112. The set of back
signals for an image is called the back channel. The back channel
principally, but not entirely, records the attenuation in the
radiation from the source 218 due to the silver metal particles 236
in the bottom-most layer 242, which is the red recording layer.
Additionally, there is some attenuation of the back channel due to
silver metal particles 234, 238 in the blue and green layers 246,
244.
[0034] The front-through signal records the radiation 230 that is
transmitted through the film 112 from the illumination source 218
in back of the film 112. The set of front-through signals for an
image is called the front-through channel. Likewise, the
back-through signal records the radiation 240 that is transmitted
through the film 112 from the source 216 in front of the film 112.
The set of back-through signals for an image is called the
back-through channel. Both through channels record essentially the
same image information since they both record the attenuation of
the radiation 230, 240 due to the silver metal particles 234, 236,
238 in all three red, green, and blue recording layers 242, 244,
246 of the film 112.
[0035] Several image processing steps are then used to convert the
illumination source radiation information for each channel to the
red, green, and blue values similar to those produced by
conventional scanners for each spot on the film 112. These steps
are used because the silver metal particles 234, 236, 238 that form
during the development process are not spectrally unique in each of
the film layers 242, 244, 246. These image processing steps are not
performed when conventional scanners are used because the dyes
which are formed with conventional chemical color processing
scanners, once initial red, green and blue values are derived for
each image, further processing of the red, green and blue values is
usually done to produce images that more accurately reproduce the
original scene and that are pleasing to the human eye.
[0036] Because the scanning described above occurs during film
development rather than after the film is developed, the digital
film processing system shown in FIGS. 1 and 2 can produce multiple
digital image files for the same frame at different film
development times, each image file having back, front, and through
values which are created using the duplex scanning method described
above. It may be desirable to create multiple duplexscanned image
files for the same frame at separate development times so that
features of the image which appear at various development times can
be recorded. During the film development process, the highlight
areas of the image (i.e., areas of the film which were exposed to
the greatest intensity of light) will develop before those areas of
the film which were exposed to a lower intensity of light (such as
areas of the film corresponding to shadows in the original scene).
Thus, a longer development time will allow shadows and other areas
of the film which were exposed to a low intensity of light to be
more fully developed, thereby providing more detail in these areas.
However, a longer development time will also reduce details and
other features of the highlight areas of the image. Thus, in
conventional film development, one development time must be
selected and this development time is typically chosen as a
compromise between highlight details, shadow details and other
features of the image which are dependent on the duration of
development. Scanning this developed film image using a
conventional film scanner will not revive any of these details
which are development time dependent. However, in the digital film
processing system of FIGS. 1 and 2, such a compromise need not be
made, as digital image files for the same image can be created at
multiple development times while the film develops, and these
multiple images can be combined to produce an enhanced image.
[0037] In FIG. 3 a configuration of a film pre-scan apparatus 300
is shown in accordance with the present invention. Prior to opening
a film canister 303, it may be inspected to ensure that it is, or
has been generally kept, in good condition, e.g., that the canister
303 is dry and does not exhibit structural damage. Upon approval
for further processing, the film 302 within the canister 303 is
then removed. Removal of the film 302 from the canister 303 may be
accomplished by opening the canister 303 mechanically or by
capturing the film 302 and pulling it out of the canister 303.
Often, removal of the film 302 leads to destruction of the canister
303 using, e.g., a shred technique or punch technique.
Alternatively, the film 302 is pulled from within the canister 303
by sliding a capturing extension into the canister 303 and pulling
the film 302 out by the film tongue. The film 302 may or may not be
cut away from the spool prior to further processing.
[0038] Once the film 302 is pulled out of its canister 303, a
scanner 304 detects for any imperfections, such as moisture, oil,
foreign objects, particles, creases, tears, or broken sprocket
holes, in the film 302. The film 302 is scanned or inspected for
imperfections in a totally light tight enclosure using an infrared
or near infrared light source and a scanner 304. The scanner 304
may be connected to a microprocessor and a memory that stores
reference data for comparison to the actual data measured by the
scanner 304. The scanner 304 may be, e.g., a reflective scanner,
wherein transmitted light, e.g., infrared or near infrared light,
strikes the film 302 and is reflected back to a sensor. The
reflected light is then measured and the difference in reflectivity
is used to determine if the film 302 is damaged or contains
imperfections. A reference sensor and a memory may be connected to
the microprocessor to provide the reference readings or data. The
reference sensor readings may be determined by the reference sensor
and stored in the memory for use by the microprocessor. The
reference sensor may be a reflective sensor or a sensor that reads
light that is transmitted through the film, is reflected by the
film or both. Alternatively or concurrently, light that is
transmitted through the film 302 may be detected and used to
measure potential film imperfections. Upon verification that there
is nothing wrong with the film 302 and that the film 302 is
suitable for DFP processing, the film 302 may then be cut, rolled
onto a spool and put into a DFP system or other processing
system.
[0039] If imperfections are detected, however, a series of remedial
steps may be taken prior to determining that the film is unsuitable
for DFP and should be routed for regular chemical processing and
development. It is important to make a determination of suitability
for DFP prior to initiating DFP because deposition of the thin
chemical film layer in DFP irreversibly renders the film unsuitable
for regular chemical bath or tank film processing.
[0040] A vacuum/blower 306 may be used to remove foreign objects
and even moisture from the film 302. Alternatively, the film 302
may be rewound back into the canister 303 and the reasons for the
rejection of the film 302 may be reported to the operator of the
pre-scan apparatus 300. A tape dispenser 308 is also shown in the
path of the film 302 in which any damaged sprockets may be
repaired. Take-up spool 310 is positioned in-line with the film 302
to provide for a place where repaired and cleaned film 302 is
stored prior to DFP. Alternatively, take-up spool 310 may be used
to gather film 302 that will not be eligible for DFP, in which case
the rejected film is once again placed in a light-tight container
for transport to standard chemical processing. Alternatively, the
film 302 is taken from the take-up spool 310 and cut in cutter 312
for capture by the rollers that will feed the film 302 into a DFP
system.
[0041] The pre-scan apparatus 300 may incorporate other remedial
measures to prepare the film 302 for processing. In the case of
water-based imperfections, e.g., when the film 302 has been exposed
to water inside the canister 303 when dropped into water or exposed
to a high moisture atmosphere, moisture content may be determined
using a hydrometer. Alternatively, moisture may be detected by
noting increased specular reflections from the emulsion side of the
film 302 relative to the nominal reflection expected for dry film.
Depending on the moisture reading, the film 302 may then be routed
into an air-based dryer or passed through rollers that remove
water. The film 302 may then be certified for DFP and routed into a
DFP apparatus.
[0042] Another type of imperfection that may be detected is dust
and other foreign objects on the surface of the film 302. A number
of debris removal systems may be used to remove foreign objects
from the film 302. For example, foreign objects may be removed by
running the film through tacky rollers that mechanically remove
foreign objects by having a higher adherence to the foreign object
than the film emulsion. The rollers may be replaced or cleaned once
a sufficient amount of foreign objects are collected on the
rollers. An embodiment of a cleaning system for such rollers is
discussed in more detail below. Foreign objects may also be removed
by a vacuum, a blower or both 306, wherein the foreign objects are
sucked or blown off the film 302. The blower/vacuum method will be
useful for the removal of dust that collects on the film during
storage or upon exposure to dusty conditions as well as removal of
damaged film sprocket debris. After cleaning, the film 302 is
scanned again to determine if the film has been cleaned
sufficiently for DFP. Upon certification for DFP the film 302 may
be routed into a DFP apparatus.
[0043] Another imperfection is the breaking of sprocket holes or
perforations. In ordinary use, the perforations along film 302,
such as still camera picture film, are engaged by drive sprockets
or a shuttle arm used to feed the film into a camera or other
device. As the film 302 is advanced, the film 302 often tears
around the perforations, particularly at the beginning and end of a
roll of film 302. In those, and other cases of damage to the
perforations, it may be desirable to repair the film 302 by bonding
a strip of pre-perforated or unperforated tape along the film 302
where damage has occurred, with the perforations of the tape
aligned with the sprocket holes of the film 302.
[0044] Apparatus and methods for attaching pre-perforated or even
non-perforated tape to film 302 are known in the art and may be
used to repair the film 302 prior to DFP. One example of such a
system is disclosed in U.S. Pat. No. 3,959,048 in which an
arrangement for bonding preperforated repair tape to motion picture
film with the precision required to align the tape perforations
with the film perforations along the length of the tape, is
disclosed. Improvements over that arrangement are disclosed in U.S.
Pat. No. 4,026,756, in which the problem of aligning the
perforations of the repair tape with the perforations of the film
along the length of the film is shown. By adding or repairing the
film 302 with tape, whether perforated or not, the potential for
problems in the DFP system is decreased.
[0045] Other improvements to sprocket repair techniques come from
the transverse alignment of the repair tape to maintain side edges
of holes in the repair tape in line with side edges of holes in the
film 302, and more particularly to assure firm bonding of the
repair tape on the film 302 along side edges of holes and between
holes. U.S. Patent Letters Pat. No. 4,249,985 issued to Stanfield
uses a pressure roller having "apertures" or recesses shaped and
spaced to receive sprockets on the sprocket wheel, thereby to apply
pressure to the adhesive tape all around a sprocket hole. Initial
adjustment of the roller during the start of each repair run may be
used to assure that the sprockets are aligned with roller
apertures. Alternatively, the pressure roller in the second roller
may be grooved. Using a grooved roller has the advantage that the
repair tape between sprocket holes is applied around each sprocket
hole. A sprocket wheel at the repair station may be used to pull
repair tape from a roll on a spindle for bonding onto perforated
film fed directly from a supply reel through a guide to the
sprocket wheel. A sponge rubber pressure roller on a spring loaded
lever may be used to press the film onto the repair tape for
pressure bonding.
[0046] The term "sponge rubber" is used herein, in a generic sense
to refer to resilient, porous (closed cell) material used for the
roller or may even be a soft rubber roller. Another example of a
suitable material that may be used is a nitrile rubber that is
commercially available, but any other nitrile rubber (a class of
synthetic rubbers) may be used. All that is required is that the
resilient material used be formed with closed cells to resemble a
sponge, with sufficient density to permit the material, cut or
formed into the shape of a roller, to function as a pressure roller
while allowing the sprockets to penetrate into the material.
[0047] FIG. 4 is a flow chart of a method for pre-scanning film in
accordance with the present invention. At block 400, the film is
removed from its container and spooled into the pre-scan system.
The film may be cut at this stage, however, it is envisioned that
if film is to be rejected it would best be kept at its full length.
At block 402, the film may be inspected visually by a user under
infrared or near infrared light during the pre-scan using the one
or more sensors of the present invention. At block 404, the status
of the film is verified, that is, a determination is made whether
remedial measures should be taken to bring the film into compliance
with the DFP system requirements as compared to reference levels.
Alternatively, the film may be rewound back into the canister and
the reasons for the rejection of the film may be reported to the
pre-scan apparatus operator. At block 406, the problem or problems,
if any, are categorized and remedial measures are taken.
[0048] Examples of remedial measures include the use of
vacuum/blower or tacky rollers to clean liquid and solid foreign
object impurities from the film. Alternatively, the problem may be
with broken, scratched, backward or bent film. If the sprockets are
broken, for example, the film is directed into a tape dispenser
that corrects for the loss of lateral support in the film for the
images that are captured on the film. The lateral support for the
images is most often necessary for the DFP process because of the
need to maintain the film as flat as possible. The determination is
made, at block 408, whether the film has been repaired and if the
remedial measures are sufficient for further processing or if the
film must still be rejected. At block 410, the film is routed into
the DFP system for further processing or the film is rejected from
DFP and directed toward a regular chemical bath processing system.
This may involve rewinding the film into the original canister or
transferring the film to a holding location for manual removal.
[0049] Other embodiments of the present invention may include
always cleaning the film and then inspecting the film, or
performing the cleaning and inspection steps in an iterative
manner. The results of the inspection may then be reported to an
operator or recorded in some manner. If the film is rejected, it
can be rolled back into the canister or stored in a new canister or
storage device. Moreover, the present invention may report the
specific reasons why the film was rejected and identify where on
the film the problems were detected.
[0050] FIG. 5 is a schematic diagram of film cleansing system 500
which can be used to efficiently clean film prior to digital film
processing. Generally, the system includes a particle removal
member 502 which removes particles from the film 112, and a
cleaning system 510 which selectively cleans particles from the
particle removal member 502 as needed.
[0051] More specifically, in this exemplary embodiment, a pair of
particle removal members 502 are provided to remove particles, such
as dust, lint, hair, particulate, and the like, from opposing
surfaces of the film 112. In this example, the particle removal
members 502 comprise particle take-off (i.e., removal) rollers, and
the film is fed between the two rollers 502. To feed the film 112
from the film canister 303 and through these rollers 502, any
suitable film transportation system can be utilized, such as those
which comprise nip rollers, sprockets, motors, belts, guides,
conveyors, and the like, and which contact the film in order to
transport the film in a predetermined path. As the film 112 makes
contact with the particle removal rollers 502 and moves
therebetween, particles are transferred from the film to the
rollers 502. This can occur by providing the rollers 502 with a
particle attraction surface 504 which removes the particles from
the film 112. This surface 504 can comprise a tacky or adhesive
surface to which the particles adhere as the roller 502 contacts
the film 112. However, any suitable particle attraction surface 504
may be utilized, such as those which attract particles through
electric charge, suction force, magnetism, or any other suitable
force.
[0052] As can be understood, the particle removal members 502 will
need periodic cleaning as film is moved therethrough and particles
build thereon. Accordingly, a cleaning system 510 can be used to
selectively clean each removal member 502 when needed or desired.
In this exemplary embodiment, each cleaning system 510 includes a
cleaning member 512 for a particle removal member 502. Each
cleaning member 512 is relatively movable with respect to its
corresponding particle removal member 502 such that it can move
into and out of contact with the particle removal member, to
selectively remove particles from the particle removal member. In
this example, the cleaning member 512 comprises a contact roller
which can be moved or indexed between a non-contacting position
(shown in FIG. 5) and a contacting position (shown in FIG. 6). When
in the contacting position of FIG. 6, the contact roller 512
removes particles from the particle removal roller 502 and thereby
cleans that roller. Accordingly, in the contacting position of FIG.
6, as the roller 502 rotates, the contact roller 512 also rotates
and the contact between the removal roller 502 and the contact
roller 512 (which can include a material over the roller) causes
particles to be transferred from the removal roller to the contact
roller, such that the removal roller is cleaned.
[0053] An adhesive or attractive force can be utilized to cause a
contact roller 512 to attract particles from a particle removal
roller 502, when in the contacting position of FIG. 6. For example,
in the exemplary embodiment of FIGS. 5 and 6, an adhesive tape 514
is fed over the contact roller 512 and used to attract the
particles from the particle removal roller 502. Accordingly, when a
roller 512 is brought in contact with a particle removal roller 502
for performing the cleaning process, the tape 514 is fed between
the rollers 502 and 512 and attracts many of the particles which
were removed from the film by the roller 502. In this way, the
roller 502 is cleaned when needed or desired.
[0054] To move the tape 514 over the contact roller 512, any of a
variety of suitable tape transport systems can be utilized. In this
embodiment, the tape is supplied via a supply roll 516 and is wound
onto a take-up roller 518. To transport the tape 514 from the
supply roll 516 to the take-up roller 518, a motor or other
suitable actuator can be utilized. For example, the tape could be
initially threaded from the supply roll 516 over the contact roller
512 and to the take-up roller 518, and the take-up roller can be
rotated by a motor, such as a DC motor, a stepper motor, or any
other suitable motor. However, other appropriate actuators,
conveyors, rollers, and the like can be utilized to transport the
tape 514.
[0055] FIG. 5 illustrates the non-contacting position of each
cleaning system 510. In this position, the particle removal rollers
502 remove particles from the opposing sides of the film 112 by
contact with the film. The film 112 then moves to the film
processing equipment, such as the duplex scanning equipment
described above for example, after being cleaned by the particle
removal rollers 502. However, particles build up on the rollers 502
and it is desirable to easily clean these rollers 502 when needed
or desired.
[0056] Accordingly, when cleaning of a roller 502 is desired, a
contact roller 512 is moved to the contacting position shown in
FIG. 6. This may occur when no film is being moved through the
system 500 or when film is being moved through the system. In this
exemplary embodiment, the contact roller 512 is movable along a
path, such as via a guide, between the two positions shown in FIGS.
5 and 6. During cleaning of the roller 502, the tape 514 is moved
from its corresponding supply roll 516 to its take-up roller 518
and passes over its corresponding contact roller 512. Accordingly,
when a cleaning system 510 is in the contacting position, the tape
514 of that system is positioned between the contact roller 512 and
the particle removal roller 502, and is in contact with both of
these rollers 502 and 512. The tape 514 is wound about the take-up
roller 518 as the cleaning takes place. As the tape 514 moves past
particle take-up roller 502, it collects particles from that
roller, and thereby cleans the roller. The tape 514 may be moved a
predetermined distance, for a predetermined time, or for a
predetermined number of revolutions of one of the rollers. As
shown, two cleaning systems 510 can be provided to clean both
particle removal members 502 (if multiple members 502 are
utilized).
[0057] Once the cleaning is complete, the movement of the tape 514
is stopped, and the contact roller 512 is returned to the
non-contacting position of FIG. 5. Periodic cleanings can occur
until all tape 514 has been transferred from the supply roll 516 to
the take-up roller 518. At this time, the tape 514 on the roller
518 can be simply discarded, and a new supply roll 516 provided,
such that new tape 514 can be threaded over the contact roller 512
to the take-up roller 518.
[0058] Cleanings can be initiated by the user by moving the contact
roller 512 to the position of FIG. 6 and beginning to wind the tape
514 about the take-up roller 518. These movements can be initiated
under the power of motors or other actuators, such as discussed
above. These movements can also be initiated automatically. For
example, a controller can initiate the movements at predetermined
times. In particular, the controller can sense when the particle
removal roller 502 has completed a given number of revolutions, and
can then initiate the movements of the cleaning system 510 to clean
the roller 502. Alternatively, the controller can sense the time
that the film cleansing system 500 has been in operation since the
last cleaning of the rollers 502, or the number of film rolls
cleaned since the last cleaning of the rollers 502, and, upon
reaching a predetermined maximum value, initiate the movements one
or more of the cleaning systems 510 to clean the rollers 502.
[0059] FIGS. 7 and 8 illustrate one exemplary system for use in
moving the contact roller 512 from the non-contacting position to
the contacting position. In this example, the contact roller 512 is
connected to a shaft 525 which is slidingly movable within a guide
524. The shaft 525 of that contact roller 512 is connected to the
shaft 519 of the take-up roller 518 via a link 522, such as a chain
or belt for example. A biasing member 520, such as a clock spring
or spiral spring for example, provides a force which keeps the
contact roller 512 in the non-contacting position when not in use.
When cleaning of a particle removal member 502 is to commence,
however, the motor or actuator connected to the shaft 519 of the
take-up roller 518 is activated and causes the shaft 519 and roller
518 to rotate. This rotation is transmitted via the linkage 522 to
cause simultaneous rotation of the shaft 525 and contact roller
512. The torque produced by this rotation lowers the contact roller
512 to the contacting position shown in FIG. 8. The rotation also
causes the tape 514 to move from the supply roll 516, over the
contact roller 512, and to the take-up roller 518. During this
movement of the tape 514, contact of the tape 514 with the particle
removal roller 502 cleans the roller 502. The motor which produces
the motion of the rollers and the tape can be any of a variety of
suitable motors, such as DC motors or stepper motors for example,
and motion of the rollers can be accomplished via suitable
linkages, gears, shafts, and related devices. A slip clutch can be
provided to prevent torque overload of the contact roller 512
against the particle removal roller 502. The clutch can be sized
and configured to slip once a predetermined maximum torque is
reached (e.g., one pound-inch), in order to keep the load
constant.
[0060] As also shown in FIGS. 7 and 8, a controller 526 can be
provided to activate the motor(s) which drive(s) the rollers 518
and 512. In this example, the controller 526 senses the number of
rotations of the particle removal roller 502 via a sensor. Once a
predetermined number of rotations is reached, the controller 526
transmits a signal to the motor to begin rotation of the shafts 519
and 525 and to thereby cause movement of the rollers 518 and 512
and movement of the tape 514. (Alternatively, the controller 526
could produce this signal after a predetermined amount of time has
past or after a predetermined usage of the system 500 is sensed.)
The torque produced by the rotations will overcome the force of the
biasing member 520 and move the rollers 512 to the contacting
position of FIG. 8. The controller 526 can continue the cleaning
for a predetermined period of time or for a predetermined number of
rotations. Then, the controller 526 can cease the production of the
activation signal to cause the rotation of the rollers 512 and 518
and movement of the tape 514 to cease, to cause the contact roller
512 to move back to the non-contacting position of FIG. 7 via the
force of the biasing member 520, and to thereby cease the cleaning
of the particle removal roller 502. The controller 520 can include
suitable circuitry, hardware and/or software to produce the motor
activation signal at the desired time.
[0061] All publications and patent applications mentioned in the
specification are indicative of the level of skill of those skilled
in the art to which this invention pertains. The entire disclosures
of all publications and patent applications mentioned herein are
hereby incorporated herein by reference to the same extent as if
each individual publication or patent application was specifically
and individually indicated to be incorporated by reference.
[0062] It is intended that the description of the present invention
provided above is but one embodiment for implementing the
invention. While specific alternatives to steps of the invention
have been described herein, additional alternatives not
specifically disclosed but known in the art are intended to fall
within the scope of the invention. Moreover, variations in the
description likely to be conceived of by those skilled in the art
still fall within the breadth and scope of the disclosure of the
present invention. Thus, it is understood that other applications
of the present invention will be apparent to those skilled in the
art upon the reading of the described embodiment and a
consideration of the appended claims and drawings.
* * * * *