Classifications

• • G—PHYSICS
  • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
  • G03C—PHOTOSENSITIVE MATERIALS FOR PHOTOGRAPHIC PURPOSES; PHOTOGRAPHIC PROCESSES, e.g. CINE, X-RAY, COLOUR, STEREO-PHOTOGRAPHIC PROCESSES; AUXILIARY PROCESSES IN PHOTOGRAPHY
  • G03C11/00—Auxiliary processes in photography
  • G03C11/02—Marking or applying text
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10S430/00—Radiation imagery chemistry: process, composition, or product thereof
  • Y10S430/146—Laser beam
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10S430/00—Radiation imagery chemistry: process, composition, or product thereof
  • Y10S430/153—Multiple image producing on single receiver
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10S430/00—Radiation imagery chemistry: process, composition, or product thereof
  • Y10S430/165—Thermal imaging composition

Definitions

• the subject of the present invention is a method of subtitling cinematographic films according to which graphic elements, characters or texts are transferred onto a cinematographic film using a laser beam traversing the area to be marked on the film.
• the surface of the emulsion of film copies is first coated with a protective layer, then the text of the subtitles is engraved by means of clichés in relief.
• the film copies are then passed through an appropriate reagent bath which destroys the emulsion in the places engraved by the plates.
• the copies are then freed from the protective layer by solution or by washing.
• the laser beam can be applied through a mask or be subjected to a deflection to travel a determined path corresponding to the inscriptions to be formed on the film.
• the quality of the result depends on the nature of the emulsion and the density of the background of the images on which the subtitles are to be engraved.
• the adjustments of the working parameters in particular the power of the radiation flux of the laser beam applied to the film and the speed of movement of the laser beam, can be carried out within fairly wide ranges of values but are highly dependent on the emulsion and make it difficult to d '' get clear and beautiful subtitles with a single pass of the laser beam on the film.
• the power, the exposure time and the wavelength are chosen so as to completely destroy the emulsion at the points of impact of the laser beam on the film.
• the engraving carried out according to this process however remains of uneven quality. Thus, there often remain shaded areas and more or less colored spots due to gelatinous residues or to an attack on the surface of the support which is difficult to control in the case of certain supports such as those made of polyester.
• the present invention aims precisely to remedy the aforementioned drawbacks and to enable rapid, economical and automated operations to be carried out, subtitling operations for cinematographic films while obtaining good quality results with clear subtitles and without burrs or gray spots or areas.
• a process of subtitling of cinematographic films according to which graphic elements, characters or texts are transferred onto a cinematographic film by means of a laser beam traversing on the film the area to be marked, characterized in that in a first step, a laser engraving operation is carried out by applying a laser beam, the speed of movement of which at the level of the film is between approximately 1 cm / s and 200 cm / s and the power at the film level is between approximately 100 milliwatts and approximately 20 watts, the V / P ratio between the speed of movement expressed in cm / s and the power at the film level, expressed in watts being between 10 and 30 and sufficiently high so that the laser beam performs a complete transformation of the emulsion in the etched areas, causing heating, softening and dislocation of the emulsion without effecting a total elimination of this transformed emulsion; and in a second step, the etched film is subjected to a treatment for cleaning the etched areas ensuring the elimination, in
• the cleaning treatment of the etched areas advantageously consists in bringing the etched film into contact with a washing bath.
• the method according to the invention is well suited to the subtitling of cinematographic films whose support consists of a cellulose derivative such as cellulose triacetate, but is also applicable to films whose support is made of plastic such as polyester.
• the method according to the invention has the advantage require less expensive equipment, consume less power, and achieve high photographic quality results without blemishes, grayish or colored areas, or line irregularities with relatively high speed scanning using the beam laser, so the overall time of the closed captioning process can be greatly reduced.
• the subtitling of cinematographic films comprises a first etching step according to which a laser source is used and a second step which consists in a cleaning treatment of the etched areas using the laser beam during the first stage.
• the second step consists in passing the film through a bath, the purpose of which is to complete the laser subtitling action in order to make the subtitles perfectly transparent.
• the laser source can be of relatively low power and can consist for example of an ionized argon laser whose emitted power is of the order of ten or twenty watts or even a semiconductor laser, the emitted power of which is of the order of a few hundred milliwatts.
• the laser beam is applied to a conventional device for optical focusing and deflection in two rectangular directions x and y parallel to the plane of the film.
• the deflection device is controlled by a computer in order to allow the laser beam to traverse on the film to be subtitled a path corresponding to the inscriptions constituting the subtitles.
• the laser beam can be focused in such a way that the diameter of the point of impact on the film, which is related to the width of the line of the characters to be written, is between approximately 30 and 300 micrometers.
• the power P1 of the laser beam applied to the level of the film which, taking into account the losses in the focusing and deflection device, corresponds by way of example to approximately half of the power P0 emitted by the source.
• laser can be kept at a relatively low value, for example between approximately 500 milliwatts and a few watts, and the speed V of movement of the laser beam on the film, which corresponds to a writing speed, is itself preferably between about 10 cm per second and 100 cm per second.
• the power P1 of the laser beam and the writing speed V are determined in such a way that, during the actual etching step of the film in a single pass of the laser beam on the film, the photographic emulsion does not is not completely eliminated, although it is burnt and partially vaporized, that is to say that the laser beam cannot damage the transparent support of the film, which support can itself be constituted as well by a cellulose triacetate only with polyester.
• the first stage of the process thus essentially consists first of all of localized transformations of the emulsion in the areas which should constitute the subtitles, by heating, softening and dislocation of the emulsion, without the emulsion being completely vaporized and eliminated.
• Such a treatment differs appreciably from the conventional methods of direct laser film etching, according to which, after the laser beam has passed, the support is exposed to form transparent areas.
• subtitles have been produced on films made up of common positive films marketed under the brands Eastmancolor, Fujicolor, Agfa-Gevaert, with line widths of 80 micrometers by applying to the level of the film, during the step of writing to the laser beam, powers P1 of 2 or 3 watts and using speeds V of movement of the laser beam of 40 cm / second, the ratio V / P1 being between approximately 12 and 20.
• a speed of movement of the laser beam at the level of the film which is between approximately 1 cm / s and 200 cm / s and the power P1 of the laser beam at the level of the film. may itself be between about 100 milliwatts and about 20 watts.
• the ratio V / P1 between the speed of movement expressed in cm / s and the power at the level of the film expressed in watts must however be between approximately 10 and 30, c that is to say sufficiently high for the laser beam to perform a complete transformation in the etched areas, causing heating, softening and dislocation of the emulsion without effecting a total elimination of this transformed emulsion.
• the support whether made of cellulose triacetate or polyester, retains in all cases total integrity, at the end of the first laser etching step, taking into account the low energies applied at the film level.
• the subtitles which consist of parts of the emulsion which have been transformed but are not completely eliminated, are however not yet really legible with all the desirable clarity.
• the second step of the process according to the invention consists, according to a preferred embodiment, in bringing the film into contact with a washing bath which ensures, in the areas of the film previously marked by the low power laser beam, the elimination of the emulsion particles heated and dislocated by the laser beam.
• the subtitles appear in the form of bald areas of the transparent support.
• the film is then subjected to a drying operation.
• the film is in contact with the bath for a period which may not exceed a few seconds.
• the chemical composition of the washing reagent bath, the temperature of this bath and the duration of contact with the film can be adapted to the particular characteristics of the photographic emulsion.
• Good results can be obtained by passing the film for a few seconds in a washing bath formed from an aqueous solution comprising a wetting agent or a detergent.
• the washing bath is advantageously heated to a temperature between around 30 ° and 80 ° C and preferably between 50 and 60 ° C.
• the washing bath can be subjected to the action of ultrasound in order to activate the action of the bath
• the film can be rinsed using jets on both sides, then subjected to a wringing and drying action.
• the washing bath is sprayed on the film in the form of jets, essentially on the face provided with the emulsion, then the film is subjected to the same rinsing, wringing and drying operations.
• the washing bath can have very diverse compositions.
• the washing bath can be alcohol-based which facilitates drying operations.
• an essential aspect of the invention lies in the implementation of a first step in which the energy applied to the film is voluntarily limited during the etching operation and the etching action is completed by a cleaning operation carried out during a second step.
• This first way makes it possible to obtain good better results than during an engraving operation exclusive to the laser beam with a single pass, while ensuring greater flexibility in the choice of operating parameters, in particular the choice of power of the laser beam and of the speed of travel, which are less conditioned by the degree of focusing of the beam or the nature of the emulsion or of the support for example.
• the second step of cleaning the etched areas making them clear and transparent may not be carried out by passing through a bath but may be carried out using a second passage of the laser beam, over the same areas to be etched with the film, the second passage also being carried out under conditions of relatively low energy input similar to those of the first step.
• the traditional methods of subtitling cinematographic films using laser beams can thus be improved, as for the quality of the result obtained, in particular in terms of regularity of layout, as soon as a first pass is made according to the first stage defined in the present description.
• a double etching corresponding to a double passage of the laser beam on the film to be subtitled under the conditions of the present invention it is thus possible to obtain excellent results, with great flexibility of implementation, in particular for supports such as cellulose triacetate.
• This technique simply leads to a significant increase in the duration of the subtitling operations which can prove to be disadvantageous especially when the subtitles include numerous inscriptions, as is in particular the case for copies of films to be provided of subtitles comprising several lines.
• a method implementing in the second step bringing the film into contact with a washing bath, rather than a second laser engraving operation, can be considered to be both faster to implement. and more universal.

Landscapes

• Physics & Mathematics (AREA)
• General Physics & Mathematics (AREA)
• Treatments Of Macromolecular Shaped Articles (AREA)
• Thermal Transfer Or Thermal Recording In General (AREA)
• Shaping Of Tube Ends By Bending Or Straightening (AREA)
• Drying Of Semiconductors (AREA)
• Physical Vapour Deposition (AREA)

Applications Claiming Priority (2)

Publications (2)

Family

ID=9417847

Family Applications (1)

Country Status (9)

Cited By (4)

Families Citing this family (6)

Citations (5)

Family Cites Families (4)

• 1991
  • 1991-10-11 FR FR9112580A patent/FR2682520B1/fr not_active Expired - Lifetime
• 1992
  • 1992-10-07 CA CA002080385A patent/CA2080385C/en not_active Expired - Fee Related
  • 1992-10-08 AT AT92402738T patent/ATE142796T1/de active
  • 1992-10-08 DE DE69213639T patent/DE69213639T2/de not_active Expired - Fee Related
  • 1992-10-08 DK DK92402738.6T patent/DK0537068T3/da active
  • 1992-10-08 EP EP92402738A patent/EP0537068B1/de not_active Expired - Lifetime
  • 1992-10-08 ES ES92402738T patent/ES2095436T3/es not_active Expired - Lifetime
  • 1992-10-09 US US07/958,786 patent/US5367348A/en not_active Expired - Lifetime
  • 1992-10-11 IL IL10340992A patent/IL103409A/en not_active IP Right Cessation

Patent Citations (5)

Non-Patent Citations (1)

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