US1065496A - Reflecting-machine. - Google Patents

Description

F. E. BALDWIN.

REFLBCTING MACHINE. APPLICATION FILED ummo, 1910.

Patented June 24, 1913.

FE-jQ/dWLVQ. avwewtoz @513 el/wozna p FBEDERIC E. BALDWIN, OF NEW N. Y.

nnrLnerme-mcnmn Specification of Letters Patent.

Application med March BO, 1910. Serial sq. 552,368.

chines, of which the following is a full,

clear, and exact description.

As these machines have heretofore been made, the subject'to be shown is placed on a flat or plain surface and inserted at the back of the machine. When used in this way the picture produced on the sereen is indistinct at the sides or edges, owing to the aberration of the rays of light. This is due to the fact that the focus of the marginal rays is nearer the lens than that of the center rays. I have discovered that this difliculty may be overcome-by mounting the post card that is to be pro ected so that it intersectsall'of the focal radii of the lens of the apparatus at the same distance from the focal center; that is to say, the post card is mounted in the arc of a circle whose center is the center of the lens. This result is attained by the employ ment of a picture-holder, preferably opaque;

which is curved in conformity with the focus of the lens.

I embod my invention in the simple ap-' ing the relation of the lens to the cardholder. Fig. 4: is a detail of the card holder, illustrating the means for securing the post card in proper position.

. A. represents the curved card holder, which may be detachably secured to the body of the apparatus so as to form the back thereof; B B are the sources of light; C C the reflectors; E the lens, which may be mounted in a tube D.

Referrin to the diagram, Fig. 3, it will be .noted is at the focal radii extend back fiom the lens, not as a flat plane but in an are, which is re resented by the curved line. A represents t 's focal curve. I arrange my card holder to follow this curve. E is the lens and the dotted line F, F is the usual flat plane on which post cards are generally laced. It is quite evident that if the focal ance of the lens E is, say, 8 inches the line S will be 8 inches long. It is also evident that the line Pextending from the lens E to the flat plane F F must be much longer than the line S and therefore were the subject, placed on the flat plane F F, most of its surface would be morethan 8 inches from the lens at the point M, and therefore out of focus; whereas, by arranging the card on the curved line A, asisaccomplished by my holder, the entire subject is brought to the proper and uniform focal distance, and con-. sequently all parts of it are rojected with equal clearness. By curving t e card holder in this manner both ends of the post card are brought into focus and therefore the picture thrown onthe screen is much better defined at the edges. This card holder has also another great advantage because, being curved entirely upon the focal radius, it acts as an additional reflector.

The rays of li ht coming from the burners B B, Fig. 2, strdre the cardholder as shown by dotted line RR and owing ture of the holder are reflected into the lens as shown by dotted hne 1- r whereas were the back flat, as shown by F F the rays would be reflected as shown by dotted line is k and not reach the lens at all. This afiords much greater illumination .on the sheet than would otherwise be obtained. This device is also subject to another advantage. 'It has always been diflicult to find a suitable means of holding these cards in place on the holder. I accomplish this by placing on the holder two ears or lugs as shown at L I), Fig. 4. The card is easily inserted under these lugs and as it is bent from its natural form by following the curve of the card holder and held in this position by the lugs the natural resiliency of the card affords sufi'lcient friction between itself and the card holder to cause it to remain in position without slipping while being shown in the machine. a I

What I therefore claim as new is:

1. A reflecting apparatus for projecting opaque pictures, having a curved picture curvature of the picture holder being in Patented June 24., was.

to this curvaconformity with the locus ot the lens and adapted to show pictures larger in field than the diameter of the lens.

3. ln a reflecting apparatus for projecting opaque pictures, in combination, a projecting lens, a picture holder back of the lens, and sources of light in 'front of the picture holder and on opposite sides oi the same, the picture holder being curved to reflect light from said sources into the lens.

4:. ln a reflecting apparatus for projecting opaque pictures, in combination, a projecting lens, a picture holder back of thelens, and a source ct light in trontoif the picture holder and to one side of the same, the picture holder being curved to reflect light from said source into the lens.

5. ln reflecting apparatus for projecting opaque pictures, in combination, a projecting lens, a mounted, and a picture holder in rear ot the lens and. lenstube, said picture holder being curved to bring the sides of a picture thereon into the iield oi the lens w'herebg light rays from the sides of the picture can enter the lens tube and lens.

do A. reflecting apparatus for projecting opaque pictures, a curved picture holder lens-tube in which the lens is.

noeaaoo provided with means adapted to engage the picture and hold the same in conformity with the curvature of the holder.

7. A holder for opaque pictures for use in an apparatus of the class described, consistingof a curved picture-supporting back,

having its two opposing curved edges fitted with means to retain the edges of the pic ,ture, substantially as specified.

8. ln projecting apparatus for opaque objects, an object-holder concave toward the lens, and a lamp located to one side of the ObjECtrhOldBI'.

9. in a projecting apparatus for opaque objects, an ob ect holder curved toward the lens, the curvature of the holder being sulostantially in conformity to the locus of the lens and adapted to show pictures larger in field than the diameter oi the lens, and a lamp located to one side of the picture holder.

ln testimony whereof 1 an my signature in the presence oi two subscribing witnesses,

FREDEltlC E.

l l itnesses Drum "W. Scores,

newson

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