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Publication numberUS1959090 A
Publication typeGrant
Publication dateMay 15, 1934
Filing dateJan 27, 1934
Priority dateMay 3, 1932
Publication numberUS 1959090 A, US 1959090A, US-A-1959090, US1959090 A, US1959090A
InventorsAlbert Wood
Original AssigneeAlbert Wood
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Reflecting sign for roads and streets
US 1959090 A
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Description  (OCR text may contain errors)

May 15, 1934. woo

REFLECTING SIGN FOR ROADS AND STREETS Original Filed May 27, 1935 M, may 7M4 v Patented May 15, 1934 I UNITED STATES :RliFLECTING SIGN roa noans' AND s'rnnn'rs Albert Wood, London, England,

Rciilcd mapplication Serial No. 673,295, Mayer, I 1933. Thisapplication January 27, 1934, Serial No.- 708,670. In Great Britain May a, 1932 4 Claims. (01. 40-135) This invention relates to reflecting signs for roads and streets which at night are illuminated by an external source of light such as the lamps of the road, shops, or of approaching vehicles.

i In such signs as used hitherto, the reflected light is dispersed over such a wide area, that the luminosity of the sign in-any one direction is of relatively low value, and the observer must therefore approach much nearer to the sign beio fore it becomes legible than would be necessary if the apparent luminosity of the sign were of higher value. 7

The object of the invention is to provide a reflecting Sign which shall reflect a larger proli portion of the rays in a direction nearly parallel to the incident rays than has been the case hitherto, whereby the sign shall be legible to an observer at a greater distance therefrom than has been the case hitherto. go The invention consists in the use, in combination with the matter to be displayed, of a lightcondensing plate of clear glass or other transparent material, the frontjface of which is provided with a plurality of small lenses of spheri- 15 cal of paraboloidal surface the foci of which are at or near the other or plane face of the plate, and a dispersively reflecting surface at said plane The light-condensing plateand the matter to so be displayed are held in a suitable frame.

Drawings are appended tically illustrating the invention. 7 V Figure 1 is a fragmentary section of a sign wherein the displayed matter is in the form of I as a flat, sheet held between the light-condensing plate and the backpf the frame. Figure 2 is a fragmentary section of asi wherein the displayed matter is in the form of a stencil held against the lentlcular face of the e light-condensing plate.

Figure 3 is'ia'fragmentary section of a si n wherein the displayed matter is painted'on the lenticulanfacej of the light-condensingplate. Figure 4 isia diagr'arn illustrating 'the action gsofthe device. i

Figures 5 audit are fragmentary. views looking at the front of the sign, illustrating the appearance of the l-brightlv illuminated parts in relazin to the parts darkened by; the'disn ayed mat- I Figure 6 being forasign as'shown Theinvemitioncan becarried into eifectinvariforms, but in all forms the lenticular face 56, of the light-condmsing plate faces outward to-' vehicle on to the surface in contact with its posterior face in a series of brilliantly illumi-' l 'lgurei being for asign as shown in Figure.

ward the source of light. In one form, Figure l, the matter to be displayed is prepared on a flat sheet 1 such as a, billposter, which in itself forms the dispersively reflecting surface, and is placed against the back 2 of the frame.- The plane face of the light-condensing plate 3 is placed in close contact therewith. This form can be used for direction and warning signs, and is also particularly advantageous for advertisingsigns, since thedisplayed matter can be changed as often as may be desired.

In another form Figure 3, they matter 6 to be displayed is painted or otherwise afllxedto the lenticular face of the light-condensing plate, and

the plane face of the plate is. treated with .a 7

white matt reflecting surface '7, for example plaster-of-Paris. Or, alternative to such treatment, the back of the frame may be painted a matt whitesurface, or a plain sheet of white paper may be held in the frame, the plane face of the light-condensing plate being placed in contact therewith.

In another form,'Fig ure 2, the matter to be displayed is prepared in the form of a stencil 4, which is held against the lenticular face of the light-condensing plate'3 whose plane face is treated as just described. A cover plate 5 of plain clear glass or other transparent material may be used to hold and protect the stencil.

From the description of the few forms given above, it is obvious that other forms modified therefrom can be used.

In Figure 4, the source of light is supposed to be the head lamp or lamps of an approaching vehicle, the rays 1' of the incident beam of light being 'then practically parallel. The action of the device is as followsz-I'helight-condensing plate concentrates the incident light from the lamps in front of the sign or of an approaching nated spots, the rest of said surface being left dark. More precisely, considering only one lens 1 of the light-condensing plate and the correspending luminous spot s, Figure 3, each ray 1' incident thereon is refracted at the lens I and divergent beam of light n, of which the axis of maximum intensity is practically parallel to that of the incident rays. The aggregate effect, as

shown in Figures 5 and 6, is substantially unisign, a very close inspection being required to distinguish the individual portions due to the individual lenses.

The luminosity of the sign as viewed by an observer will, be greater the closer he is to the said axis of maximum intensity.- In the case of an approaching vehicle whose head lamps illuminate the sign, the luminosity as viewed by the driver is the greatest possible.

It is to be observed that if the reflecting surface behind the light-condensing plate is a mirror or the like giving the angle of reflection equal to that of incidence, the desired effect as described is not produced.

I claim:

1. In a reflector sign for illumination by an external source of light, a light-condensing plate of transparent material the rear face of which is plane and the front face of which is provided with a plurality of small lenses of convex external surface the foci of which are at the plane face of the plate, and a medium providing a dispersively reflecting surface at said plane face.

2. In a reflector sign for illumination by an external source of light, a light-condensing plate of transparent material the rear face of which is plane and the front'face of which is provided with a plurality of small lenses of convex external surface the foci of which are at the plane face of the plate, and a sheet containing the matter to be displayed placed in close contact with said plane face.

3. In a reflector sign for illumination by an external source of light, a light-condensing plate of transparent material the rear face of which is plane and the front face of which is provided with a plurality of small lenses of convex external surface the foci of which are at the plane face of the plate, displayed matter painted on the lenticular face of the plate, and a medium providing a white dispersively reflecting surface :91; said plane face.

4. In a reflector sign for illumination by an external source of light, a light-condensing plate of transparent material the rear face of which is plane and the front face of which is provided with a plurality of small lenses of convex external surface the foci of which are at the plane face of the plate; a medium providing a white dis-.

persively reflecting surface at said plane face, a stencil in front of the light condensing plate, and a cover plate of transparent material in front of the stencil ALBERT WOOD.

Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2421277 *May 12, 1943May 27, 1947Luce Richard WReflective sign
US2444356 *May 12, 1943Jun 29, 1948Luce Richard WRetrodirective light-reflecting device
US2948191 *Jun 6, 1956Aug 9, 1960Cataphote CorpRetroreflecting surface
US5073005 *May 2, 1988Dec 17, 1991Hubbs Machine & ManufacturingRetro-reflective photogrammetric target
US6490819 *Nov 27, 2000Dec 10, 2002Honda Giken Kogyo Kabushiki KaishaDecorative sheet
US7224533 *Nov 8, 2004May 29, 2007Hewlett-Packard Development Company, L.P.Optically retro-reflecting sphere
US7698826Jan 28, 2008Apr 20, 2010Hubbs Machine & Manufacturing Co.Refurbishable retro-reflective photogrammetric target
Classifications
U.S. Classification40/615, 359/542
International ClassificationG02B5/126, G02B5/12
Cooperative ClassificationG02B5/126
European ClassificationG02B5/126