US1881128A - Projection screen - Google Patents

Description

" fggfw I SEARCH ROOM OGL 4, 1932' y A c. PAYNE ET A1.

l 4 nossc'rrou scasn .FBSTITUTE FR'MISS'NG OR 19g-igual .Filed Nav. 2a, 192s A o i 5%, Www-:mung

Patented Oct. 4, 1932 PATENT OFFlCE ARTHUR C. PAYNE, F KEW GARDENS, AND DAVID F. NEWMAN, OF FREI-EPORT, NEW

YORK, ASSIGNORS TO TRANS-LUX DAYLIGHT PICTURE SCREEN CORYORATION, OF'

NEW YORK, N. Y., A CORPORATION OF DELAWARE rnoJEcrIoN SCREEN .Application led November 28, 1925, Serial No. 72,029. Renewed May 24, 1930.

This invention relates to screens for projecting systems in connection with moving pictures, stereopticon views, or the like, such screens being utilizable ordinarily for rear projection although, under some circumstances, tliey may be utilized for iront projection.

The principal object of the invention is to provide a translucent screen on which the picture ma;` be projected in a lighted or darkened room at the option of the operator. In screens of this type the picture is projected from the rear; that is. projected on the screen on the opposite side from the spectator, the spectator being in the path of the direct light instead of receiving the retlected light from the picture.

Another object is to provide a screen in which the light thrown by the projectionl machine passes through the screen and gives the picture an appearance of unusual sharpf ness. -Another object is to provide a translucent screen which is flexible and which may be readily rolled for transportation or storage, the folds of the screen not. sticking to the adjacent fold when stored in a rolled condition.

Another objectis to provide a screen which may be adapted to varying;r climatic condi-` tions, such as ditierenees in temperatures and luuuidity,by merely varying the quantity of the ingredients used, llcretofore screens of this type have been made but it has been found that a screen made of one. material adapted to be used under one climatic coudition will be wholly unsuitable if used under n ditiereut and widely vai-,vingr climat-ic condition, so that screens for warm, humid climates would have to be made of one material while screens for cold. dry climates would have to be made of other materials. ily this invention the dill'erenees in tenuwrature can be easily taken eare ot' b r varying the relative quantities ol ingredients used without the necessity of usine other and dill'erent. ingredients.

Another ohjeet of this invention is to provide a screen which will not mildew when left rolled in a damp place for along period of time.

Another object of this invention `is to provide a screen which will be V'ernilni" In other words. this inven ion relates to a screen which can be made adaptable for all ranges of temperature and climate and which may be rolled indefinitely without deterioration and which will also produce an image of unusual sharpness, and which can be used in a lighted room as well as in a darkened one.

Other objects of the invention will appear from the foliowingg description. This screen is an improvement on the type of screen disclosed in Patent No. 1.151.502, issued to Troeger, on August- :2-l, 1915.

, A very satisfactory screen has been produced by using the following formula. The portions given are by weight- Parti Glue 100 'Water 208 Sodium fluoride 4 Glycerine 100 Special formula 80 Cobaltblue 1.5

The `flue and `f vlycerine form the screen body and these materials may he any suitable character. The sodium fluoride acts as a gcrmieide, a luu'teriacide, fungicide, preservative or the. like and. in lieu thereof, other agents having similar properties may he utili'fzed. 'llu roba t lueserves as a lifhttilterine' agent it it. or equivalent materu may be utilized, if desired, to produce a screen otsuch character that it will be neutral or nearly so when acted upon by the lightt' rom the projector whereby a large number of the usual vellow rays of the projecting light souri-e are tillered ont.

' In preparing the screen, the glue may be soaked for au extended period. as from six tu eight. hours. and then brought into solution h v a slow heat and frequent. stirring, the temlwrature. }uel'eralvl not greatly exceeding ITS degrees l". lrel'erahly.the sodium lluoride is separatel dissolved in water and added to the glue before the aforesaid have been found to give extremely good reapplcaton of heat, sults in tropics where only one part ot cupric Ibqglycerine may now bg added, the nuxsulphate is used. Obviously, 1n heu of cupric turejhereaftcr'being'tl'io'roughly stirred and sulphate, other agents having similar prop- 5 tireniijerrably'strained;" W'hilc the xnix'- crties may be utilized. o

Turc xs being stirred'a'nd while maintained 0n the accompanying drawing, we have substantially at the same temperature as illustratedascreen-formingarrangementand noted above, it is desirable that the special on said drawing:

formula be added, the latter preferably hav- Figure 1 is a perspective view, partly in in" been previously strained. section, showing lthe matrix or table upon lPreicrably, the cobalt blue coloring mawhlch the screen is supported during` manuterial is stirred in last, this material being facture thereof; added a few drops at a time until the proper Fig. 2 is a transverse, vertical sectionrl coloris reached. After the mixture has cooled View of the table of Fig. 1 and showing a some or 40 degrees F., its consistency frame above the table with a stretched sheet so should be about that of a medium syrup at tl1er eon; room temperature. It'. on account of the type Fig. 3 is a vertical, sectional view of a porof glue used, the solution should be too thick, tion of the screen before the sheet is embedded more ot the sodium fluoride in water solninthe viscous screen material; and 2 tion may be added. The molding operation Fig. 4 1s a view corresponding with Fig. 3 8J may now follow. showing the finished product.

d'I`l\ e special formula is usednas` a dilusgl As shown on the drawing, a drj7 sheet 1 or light-dill'using agent, and alsoservesas 0f .Suitable fabric, as georgette silk, from adatxnospherie agent* in the sense that the `whlclunfgrease'ad other'material have n 25 completed screen is thereby'put in a condibeen suitablyv removed. is stretched on a 'o tion resisting the otherwise damaging efframedetining an openingjust large enough fects of the atmosphere. Preferably, the totsnugly around the upright edge or wall3 special formula is prepared as followszvto 4of the matrix table -l on which the screen parts of casein b vweight is added 20S is to be molded. n 3 parts of water, 12.5 parts of borax, and 1 part After the matrix table has been brought of cupric su`q)h.xte.- The method of preparto suitable temperature conditions, ordinaring this formula is as follows: ily above 100 degrees F., and with the screen- The casein is placed in parts of water forming -material in proper condition, and and stirred until all of the casein has been `of proper temperature, preferably somewhat moistened. The borax and cupric sulphate higher than the table temperature. said mateare dissolved with the remaining 7S parts of rial should be poured on or applied to the water and added to the casein mixture during table, preferably to such an extent that it gentle stirring of the latter. The mixture slightly overflows the aforesaid wall 3, the

will then begin to thicken and within fortyheight of which determines the thickness of eight hours will have become a thin smooth the screen. The excess material should now 1` fluid which should be well stirred and left be removed, as bya straight edge. :titer this to ripen for a suitable period. as tive days, operation, the molded material T is flush l. more or less, after which it is ready for use. with the top surface of the aforesaid wall 3 "f/ The casein serves as a 1ightdh'fnsingagent as shown particularly in Fig. '2. I n" After the excess material has been removed 1o ntffhwa fer`ire'r`1'l'1n'enint may vary some;

what. dcpendi'ngupon the type thereof. Ohas stated above, the sheet of sill: is suitably inSIy', in' accordance with certain phases of lowered toward and into engagement with our invention, other light-diiusing agents the upper surface of the material on the mai maybe substituted for the casein. The horax trix table, care being taken to avoid cntrapn functions as a solvent for the casein. ment ot' air between the silk sheet and the l `.Thc cupi-ic sulphate serves primarily as an,v screen-forming material. In so doing. the agent resisting action of the atmosphere on frame holdingr the sill: sheet comes into posi- "the completed screen; it actsin an antih`vdro tion around the borderingT wall 3 ot the ma- "scopie manner and serves to' harden, dry trix table. and thereupon the silk sheet sinks o and/or cure the. screen. Therefore. the use into or auialgznuatcs with the screen-forming of cupric sulphate renders the screen more material. At this time` application ol heat moistnre-rcsisting without materially deto the matrix table `should he dscontinnml trat-ting from its elasticity and llexiblity. :nuhaftcr a suitable coolingr period. as two or 'hilcthcamount ol'cnpricsulphatehasbccn three hours. has elapsed. a knife should he V.- 3 given ns- 1 mrt.- where it. is known that the passed between the frame '.2 and the wall :l to scrccn is tolm used in a tropical climate. this sever said sheet. from its frame. 'l`lu\rcal'tcr. amount may he increased from l to :l parts the molded screen may be removed from the in order to incl-case the moisture-resisting nuurixtahlc in :in vsuitablc manner. properties of the screen. llowcrcr. screens l'lcr completion of thc screen as just dc- 1:.) made in accordance with the formula as given scribed, the edges thcreol should be suitably v bound, as by canvas strips, or equivalent, adhesively secured thereto and provided with eyelets. When the screen is installed for use, a suitable frame should be provided and the screen positioned tautly therein, as by a rope passed through the eyelets and engaging the frame.

Although we have described the screenforming material of our invention as formed into a' completed screen by a molding operation and utilized in connection with a fabric sheet, it shall be understood that our invention is not to be so limited since the fabric sheet may be omitted, if desired, and the molding operation may he effected otherwise than as herein described.

'While the invention has been described with respect to a certain particular preferred example which gives satisfactory results, it will bc understood by those skilled in the art after understanding the invention, that various changes and modifications may be made without departing from the .spirit and scope of the invention and it is intended therefore in the appended claims to cover all such changes and modifications.

'hat is claimed as new and desired tobe secured by Letters Patent is:

1. A projection screen containing gglatinous material. glycerine and a liquid principally, a light -diffusing agent, a curing agent, n gcrinicidgand having a fibrous strengthening material incorporated therein, said light diil'iising agent being substantially uniformly incorporated in the other screen-forming materials.

2. A projection screen containing glue,

glyccrine and a liquid. principally, alight diffusing ugent, a germicide substantially incapable of exercising a hardening effect on the screen, a curingagent, eQl oi -ing material, and having a reinforcing material in-v corporated therein.

3. A projectionl screen composed principally of gelatinons material, glycerine and water and containing a light diffusing agent, a curing agent, and having a tiberous strengthening material incorporated therein, said light dill'nsing agent being substantially uniformly incorporated in the other screenforining materials.

4. A projection screen resistant to atmos-` pheric and climatic conditions comprising a fibrous hase incorporated in a composition comprising a gclatinons material and casein.

5. A lcxihlc. projection screen resistant to atmospheric. and climatic conditions coniprising a lilii'ons hase incorporated in a coniposition `comprising gclatinous material, casein and cupi-ic sulphate.

(l. projection screen resistant to atmospliric and climatic conditions comprising a libi'ous hase incorporated in a composition comprising lill) pai-ts ol' glue, Uh pai-ts of water, 10 parts of sodium fluoride, 10U parts atiiious iiaterial,

'of glycerine and 80 parts of a composition comprising parts of casein, 130 parts of Water 12% parts of borax and 1 part of cnpric sulphate.

7. A projection screen comprising a body fnsing agent and a light-filtering agent sub-y stantially uniformly incorporated therein.

10. 'A projection screen comprising a body section having a light-diffusing agent, a lightfiltering agent, and a gerniicidal agent substantially uniformly incorporated therein.

v11. A projection screen containing gelatinoiis material, glycerine and a liquid principally, a light diil'using agent, a curing agent, a germicide, coloring material, and having a fibrous strengthening material ncorporated-therein, said light diffusing agent -being substantially uniformly incorporated in the other screen forming materials.

1:2. A projection sci-een composed of gelf'lycerine anda liquid rincipally, idal agen an alka i, a curing gen co oring nia erial, and having a sheet of fibrous material incorporated tligrein. i 13.. A projection screen composed of gelatinuous material, glycerine, and a liquid principally, casein, sodium fluoride, borax, cupric sulpliate. 'c`ol0ring material, and having al sheet of fibrous material incorporated there- 1n.

In testimony whereof. ive have affixed our signatures to this specification.

ARTHUR C. PAYNE. DAVID F. NEVLXN.

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