US 3818213 A
A decorative article including a source of low level light is provided in a form which gives enhanced decorative effects. More specifically a small source of more concentrated light is incorporated with cast decorative elements so that a spreading and softening of the more concentrated light is achieved along with a heightening of the decorative appearance of the article due to distribution and emanation of light from cast portions.
Claims available in
Description (OCR text may contain errors)
United States Patent [191 Rochford et al.
[ June 18, 1974 CAST RESIN GLOW LAMP PRODUCT  Inventors: Paul E. Rochiord, East Greenwich;
Celia A. Rochiord, Kingston, both of  Assignee: General electric Company, New
[22-] Filed: Oct. 4, 1971  Appl. No.: 186,060
 US. Cl. 240/10 R, 240/106 R  Int. Cl F2ls 1/00  Field of Search 240/10 R, 92, 106 R  References Cited UNITED STATES PATENTS 2,479,258 8/1949 Raper 240/10 2,839,670 6/1958 Gladstone l 240/10 X 3,020,395 2/1962 Peltz 240/106 3,393,310 7/1968 Ream 240/10 3,425,146 2/1969 Winstanley 240/10 X 3,488,485 l/l970 McGann 240/106 X Primary ExaminerSamuel S. Matthews Assistant Examiner-Michael L. Gellner Attorney, Agent, or Firm-P. E. Rochford; P. L. Schlamp [5 7] ABSTRACT A decorative article including a source of low level light is provided in a form which gives enhanced decorative effects. More specifically a small source of more concentrated light is incorporated with cast decorative elements so that a spreading and softening of the more concentrated light is achieved along with a heightening of the decorative appearance of the article due to distribution and emanation of light from cast portions.
7 Claims, 12 Drawing Figures 1 CAST RESIN GLOW LAMP PRODUCT The present invention relates to a decorative article emitting a low level of light, more particularly it relates to a low level lighting source having combined therewith decorative elements for distribution of light of said source to make the lighting and decorative elements thereof cooperate for enhanced decorative effects.
Many articles are known in commerce which produce low levels of light for a variety of functional purposes. Such lights are found for example in switches, that is for example, in the push button of switches or in the toggle of switches so that the switch may be located in thedark. Also lights are found in various control devices as indicator lights to indicate the energization of a controlled circuit.
Still other low level lighting articles are employed as sources of light as for example as night lights within a residence. The value of these articles to consumers and users in the home is increased where the light and the article with which the light is associated have decorative features which make the article more acceptable to the user in its normal location. There is normally a functional use for a low level of light within a home. However, the light source need not be purely functional in appearance and the non-functional appearance can be quite important to the acceptability and actual use of light sources where they are needed. In other words where use of a guide light is desirable in a home for safety sake it is more likely to be used if the light is decorative than if it is purely functional in appearance. In an article as illustrated above it is preferable to have the light in a housing which is compatible with the decor of the home. Further where low level lighting articles have decoration compatible with home decoration it is even more likely that they will be given wider use or employment within the home to serve safety and other functions because of their better appearance features. For example more such low level lights may be used for safety in lighting hallways or in deterring intruders.
In addition the appearance features of a decorative article may be enhanced by a low level light source. Thus it is possible to produce a decorative article the decorative features of which represent the main product values to a user, and these features may be heightened and enhanced by the presence of a low level light source. For such an article the functional lighting as of hallways and the like may be a very minor or negligable part of the product features but the decorative value of the article may be its primary value to the user.
It is accordingly one object of the present invention to provide a decorative low level lighting article in which there is greater cooperation between the decorative effects produced by the decorative elements and the light eminating from the decorative element thereof.
Another object of the present invention is to produce a decorative low lighting article at a relatively low cost.
Still another object of the present invention is to provide a decorative low level lighting article in which unique and novel decorative effects are incorporated directly into the article.
A further object of the present invention is to provide a decorative low level lighting article in which the decoration of the article may be modified and changed at relatively low cost.
Still another object of the present invention is to provide a low level lighting article in which the light transmission through the article is more efficient and in which accordingly the low level of light available is used more effectively in enhancing the decorative attributes of the article.
Other objects and advantages of the invention will be in part apparent and in part pointed out in the description which follows.
In one of its broader aspects the objects of the present invention may be achieved by providing a decorative low level lighting article comprising:
a light source with low heat emission,
means for connecting said light source to a source of electric power said light source being at least partially embedded in plastic,
a decorative diffuser formed at least in part of cast plastic said diffuser being disposed to receive light passing through plastic embedding at least a portion of the light source said diffuser having a portion with higher light transmission properties at greater distances from said light source and having a portion of lower light transmission more proximate said light source.
The preferred manner for carrying the invention into effect is explained with reference to the accompanying drawings in which:
FIG. 1 is a perspective view of a guide light usable in forming products of the present invention.
FIG. 2 is a side elevation of a product formed pursuant to the present invention showing a guide light such as illustrated in FIG. I and a decorative element in casting position.
FIG. 3 is a view similar to that of FIG. 2 but illustrating the horizontally disposed cast decorative element in vertical section.
FIG. 4 is a view similar to that of FIG. 3 but illustrating in vertical section an alternative form of decorative diffuser element.
FIG. 4A is a view similar to that of FIG. 4 but shwoing the cast element in phantom.
FIG. 5 is a view similar to that of FIG. 3 showing in vertical section still another alternative form of decorative diffuser element.
FIG. 6 is a front elevation of a decorative element similar to that illustrated in side elevation in FIGS. 2, 3, and 4.
FIG. 7 is a top plan view of an assembly of electrical elements usable in forming guide light products of this invention.
FIG. 8 is a perspective view of an assembly of the essential elements of FIG. 7 into a pre-formed frame.
FIG. 9 is a horizontal section through a cast body showing the element of FIG. 8 embedded in the cast body.
FIG. 10 is a view similar to that of FIG. 9 showing another form of frame in place in a cast body.
FIG. 11 shows still another form of frame as seen in FIG. 9 but in a multi-layer cast body.
In the description which follows the term embedded in plastic or similar term is meant to convey that the plastic directly contacts the transparent envelope of the light source so that light from the source passes directly into the plastic as there is no air gap between glass envelope and plastic through which light must pass or in which reflection and diffraction and diffusion of light can occur to an appreciable degree.
Referring first to FIG. I a conventional glow lamp article is shown in a form which has been commercially available for a number of years. In this article a pair of blades and 12, of the folded strip variety familiar in the art, extend back from a base 18 of a molded plastic body 14. The inner ends of blades 10 and 12 are encased directly into the base 18 of the molded body 14 during the molding operation and the body serves effectively as a handle for manipulating the blades into and from wall and other electrical receptacles.
Also encased within the plastic body 14 is a light source of low level emission and preferably one, such as a glow lamp, from which heat emission is also quite low. Glow lamps have been encased for example in a tower like structure 16 rising from the generally rectangular base 18. Electrical connections of the light source to the blades, including a resistor for controlling the level of power flowing to the bulb and the level of light from the source, are made prior to the molding operation and may have the general form shown in FIG. 7.
Bulb enclosure 16 may have windows such as 17 formed by simply not depositing any plastic over portions of the glass bulb enclosing the glow lamp electrodes.
Turning now to FIGS. 2 through 6 there are illustrated several forms of productwhich are formed according to this invention. Each includes an article as shown in FIG. 1 as a component part thereof.
A decorative body is shown for purposes of illustration in the form of a leaf. The body as seen in FIG. 2 is illustrated as formed directly on and about the forward surfaces of the molded plastic casing 14 including base 18 and bulb enclosure 16.
The manner in which this may be accomplished is described with reference first to FIG. 3 which is a vertical section through the cast resin portion only of the article of FIG. 2.
The cast resin portion 20 is formed in an open mold by introducing casting resin into the mold. A lower layer 22 is formed by introduction of a first quantity of the liquid and this liquid layer solidified by the normal hardening process of the liquid casting polymer. The guide light 14 is then positioned on the reacted layer when the reaction has progressed far enough for the weight of the light to be supported. The hardening layer actually becomes very tacky and the guide light can be cemented into position as further hardening of the polymer takes place.
In either case, that is whether the lower layer is hardened further after the light is set in place or not, a second addition of the liquid polymer is made to bring the level up and around the polymer and glass envelope of the guide light 14 where it is exposed. The polymer may in this case and preferably does cover windows such as 17 seen in FIG. 1 to accept light directly from the glass envelope of the light source. Portions of the second layer 24 extend outward beyond the outer perimeter 25 of the first layer so that outer portions such as 26 may be viewed from the front as illustrated in FIG. 6.
By including in layer 22 a relatively low concentration of pigment and similar material which diffuses light the concentrated smaller light spot or hot spot of light of the source may be spread out so that light coming through layer 22 is softened in its path of difi'usion through the pigment or other light diffuser of layer 22.
By contrast where the material of outer layer 24 is composed of more transparent ingredients, the travel of light through this layer is facilitated and an emission of light from the outer portions of the article is enhanced. With this greater emission from the outermore transparent portions, the outer portion is made more evident in viewing the overall article and the appearance of the article is enhanced.
Special appearance features are feasible in a low level lighting article having a more concentrated light source where a decorative diffuser is provided having greater width and height than depth and where less transparent material is incorporated closer to the light source. The less transparent material softens and spreads the light from its more concentrated source. Also where more transparent material is disposed at greater distances laterally from the light source, emission of light from the surfaces of the cast decorative element occurs at greater distances laterally from the light source.
In using the term less transparent the intent is to include not only more opague materials but the intent is to include as well particulate or other materials which give a higher level refraction or diffusion of light. For example a pigment material may be dispersed in the casting resin used in forming the first layer. Alternatively as illustrated for example in FIG. 4 a preformed diffuser 30 may be included in a cast resin body to provide the less transparent material in a position to soften or block light emitted from the more concentrated source. Heightened decorative effect is achieved for example where the diffuser 30 allows only a very low level of light to be transmitted through the diffuser but where the cast resin 32 of the remainder of the decorative element is sufficiently transparent to emit in effect a halo of light from the outer portions of the diffuser.
To incorporate the diffuser element 30 in the cast plastic body 32 the body may be formed in two layers as described with reference to FIG. 3. No line of demarcation need be formed where the two layers of cast polymer have the same optical properties.
Alternatively the diffuser element may be deposited on a pedestal 34 which can itself make some decorative contribution to the overall product. An illustration is an opague grill work or filigree through the openings of which the light passing through diffuser 30 may be seen. Such a pedestal may be mounted to the diffuser 30 and the two elements may be mounted to the guide light 14 or they may be included separately into a mold prior to introducing the liquid polymer to form the cast portion of the overall diffuser. This arrangement of diffuser, pedestal and guide light is seen more clearly with reference to FIG. 4A where the relation of the parts to the form of a mold is evident from the mold outline shown in phantom.
A casting resin such as liquid polyesters or epoxy which includes a quantity or peroxide, polyamine or similar catalyst admixed therewith is effective in strongly anchoring the cast portion of a diffuser to the polystyrene of a glow lamp article such as 14. Such polyester casting resin is also effective in bonding styrene elements such as diffuser 30 and/or pedestal 34 into the cast iron portion of the diffuser and to effectively anchor such elements to the molded polystyrene body of a guide light element such as 14.
The casting resin used in connection with the articles described herein is for the most part casting polyester as described in the Modern Plastics Encyclopedia 1970-71 edition published by McGraw-l-lill Publishing Company of New York. Other casting resins are described in the encyclopedia under the heading casting of thermosets. While these other materials may be employed the combination of cost and optical and other properties of polyester make it a preferred material for forming articles as described herein.
By a casting resin is meant generally a resin which is applied to a mold or other shape giving element in a liquid or paste or gel state and which undergoes a chemical change in the nature of a curing or cross linking or chain extending or setting as a result of which the liquid or paste is converted to a solid and remains a solid at temperatures at which it was previously a liquid or paste as well as at higher temperatures.
The anchoring of guide light 14 and diffuser element 30 is important in that the diffuser serves as a handle for introducing the blades and 12 of the guide light portion of the article into and removing the blades from wall and other receptacles.
The form of an open mold usable in forming decorative low level lighting articles according to the present invention is shown in phantom in FIG. 3. Other fonns of molds as for example expendable molds formed as by vacuum or pressure forming of plastic sheet material may be employed.
In this latter case the original of a decorative article is first formed in modeling material by techniques known to model makers and artists. A suitable plastic sheet as of polyetheylene may then be heated and drawn tight over one side of the model as by conventional vacuum or pressure forming techniques. After being formed in this way the plastic sheet may be removed from the model and used as a mold. This plastic sheet mold may then be used in forming decorative articles conforming in shape to the model by introducing casting material therein as described above to form layers, to embed articles included in the mold, and to anchor the glow lamp securely in the finished molded article.
Turning next to FIG. 5 a decorative article is shown in vertical section in which the cast element has three layers. The lowest layer 40 is seen to have particulate matter 42 dispersed therein.
The next upper layer 44 is uneven and is produced by pouring casting resin into a mold while the mold is tilted. Layer 46 is formed with the mold in the horizontal position.
All three layers 40, 44, and 46 are decorative layers through which light is diffused from the lamp of guide light 14. Where layer 44 contains a transparent red dye and layer 46 a transparent yellow dye the overlapped portions will appear as various shades of orange. Where layer 40 has a pigment as a white pigment dispersed in the liquid resin from which the resin is formed and accordingly in the cast resin layer, the light will pass first just through the yellow red layers giving the light an orange cast and light coming through the white difiuser will be seen as orange. Inclusions 42 which are more opague than the layer will stand out in diffused fashion as darkened areas. Where the inclusions 42 are more transparent they may appear as brighter areas depending on their size shape and refractive index.
Layer 48 which embeds the guide light 14 is preferably of a more transparent plastic both to facilitate forward transmission of light and to increase transmission toward the perimeter 49.
A reflector 50 which may be in the form of a reflective or white coating or film may be mounted to the back of the guide light, i.e., the side from which the blades extend to increase transmission of light into the cast plastic portion of the article.
Generally a molded article such as shown in FIG. 1 does not distribute its light uniformly in all directions in a plane generally normal to the blades 10, 12.
Less light is emitted in a downward direction where downward in this sense means toward and through base 18.
This is partly because of the greater number of electrical elements present in that direction and partly because of the-larger mass of polymer in base 18. Two measures give more effective use of light emitted from such a base. One is to form the molded article of clear or transparent plastic. Another is to place the article as shown in FIGS. 2, 3, and 4 with the base eccentrically placed nearer to one edge of the article. The preferred arrangement is one by which the light transmission and diffusion through the article enhances the esthetic properties of the article. In general with a guide light article such as that of FIG. 1 the preferred orientation is with the light emitting portion closer to the geometric center and with the base closer to an edge.
In fact where even distribution of light is sought both the light emitting portion and the base may be displaced radially from the center in the same direction. This is illustrated in FIG. 4 for example where it will be seen that the entire guide light article 14 including the light source in tower l6 and the base 18 is positioned to one side of the cast diffuser. However, because of the uneven emanation of light the eccentric placement of the light source does result in a more even distribution of light in and from the diffuser than would be the case if the geometric center of the guide light article 14 were placed in the geometric center of diffuser 20.
The eccentric placement of guide light article toward an edge of a decorative article as provided pursuant to this invention can be an advantage particularly in dealing with articles of larger dimensions in avoiding interference with access to the second receptacle of a duplex receptacle.
Where a more central placement of light source and power blades is preferred another form of guide light and power supply may be employed.
An alternative fonn of a light bearing unit usable in connection with the present invention is shown in FIG. 8. In this form of the product a bulb 81 and resistor 79 and associated conductors are disposed on the face of a plate 80. The blades 86 and 88 which receive power are inserted through the plate 80 through the blade slots 82 and 84. The bladeslots are shaped to permit the lower ends of the blades 87 and 89 to pass through but to hold the upper end and lock the upper ends 83 and 85 in place in the plate. Because as the blades are inserted in place, the resistor and glow lamp are attached to the captive ends 83 and 85 of the blades prior to insertion in theplate, the glow lamp and resistor combination are held in the plate and may be positioned manually to orient the lamp in any desired position relative to the plate.
Referring next to FIG. 9 a view of a decorative guide light product is given which incorporates a plate, blade, and bulb assembly as seen in FIG. 8 but in this case in a cast plastic body 90.
A diffuser element 92 may be provided in front of and extending the length of bulb 81 to soften light emanating from the bulb and distribute it more evenly through the cast plastic body 90. Diffuser 92 may have a thicker mid-section 93 where it is directly in front of the lamp and narrower edge sections 94 at greater distances from the light. This has the effect of allowing the light to pass through the lens shaped diffuser 92 more uniformly and yield a more uniformly lighted outer surface to the diffuser.
' The cast body 90 may have indentations such as 96 and 98 which permit the diffuser and bulb, plate and blade sub-assembly to be supported in a mold in position for the casting of the decorative body 90 thereabout. Means not shown may be employed to hold the diffuser 92 to the bulb, plate, blade sub-assembly. The diffuser element may in fact be formed as an element of the plate and be attached to the plate as at one end at the time of formation of the plate.
While the structure of FIGS. 8 and 9 is adequate to serve the purposes set out above in the respective descriptions, where heavier duty use of the article is to be made a more secure linking of the blades into the plate and a more secure linking of the plate into a cast decorative body is feasible. Such an arrangement is illustrated in FIG. 10.
Referring now to this figure the cast body 100 may have the form of a flower for which diffuser 102 represents the pistal and stamen or center and the cast portion 100 represents the petals.
As shown center 102 may have a cupped upper surface to receive and support the bulb, plate, blade subassembly during casting. The diffuser 102 is supported on the bottom of the mold and it in turn supports the sub-assembly through bulb 101.
Turning now to the sub-assembly the blades 103 and 104 are of the folded strip variety with both secured ends housed in the plate 105. Plate 105 is thicker than that shown in FIGS. 8 and 9 and has a different structure for the blade slots. This structure of the blades is also different and includes a spring finger or detent 106 bent out of the inner strip of the blade and capable of spring action. As the blade is passed through the narrower end of the blade slot 109 the detent is bent in and passes through the smaller hole. After passing through this narrower portion the detent springs open into recess 107. Because the recess 107 extends only through a portion of plate 105 the blade cannot return through the plate. Also because the inner ends 108 of the blades are bent at an angle to the blade strip the blades cannot move outward through the plate. A very low cost assembly of blades, resistor, bulb and plate is achieved in this fashion.
Referring to FIG. 7 the assembly of blades 103 and 104, resistor 97, insulating sleeve 96 and bulb 81 is seen in the pre-assembly array.
As seen inner blade ends 95 may be straight in the pre-assembled condition and may be bent at an angle to lock them against withdraw after detent 106 has snapped into place in the chamber 107.
The plate is securely anchored in the cast plastic partly due to its outwardly extending leg portions 99. A portion 98 of cast plastic body 100 is deposited in back of the plate at these edges and securely looks it in place against any force which might be applied to dislodge it.
In FIG. 11 a set of legs 110 are shown extending out from the plate 112 an extent which takes the legs beyond the thickness of the bulb 114 and resistor (not shown) combination. The legs 110 protrude to an extent which takes them out beyond the thickness of bulb 114 for a particular disposition of the bulb. In other words the legs 110 may be longer where it is desired to have the bulb I14 disposed at an angle to the surface of the plate 112. This might be for example where an end of the bulb is to be pitched forward on an angle of 20 or 30 from parallel to the plate.
The main purpose of the extended set of legs 110 is to permit the location of the plate and blade and bulb assembly relative to the liquid plastic into which the assembly is to be cast. The legs 110 permit the plate 112 to be set into a receptacle having the liquid plastic in it and to stand so that the liquid embeds the resistor, bulb, legs, and partially embeds the plate and so that the blades are properly oriented relative to the plastic which is cast about the plate and bulb.
A hole 111 may be provided in the plate at a location behind the bulb to avoid entrapment of air as the assembly is inserted into a pool of liquid plastic preparatory to casting and to permit the plastic to envelop the bulb and to rise partially up through the hole provided in the plate. Alternatively air may escape through the blade slots in the disc.
Normally the plate is inserted into the liquid plastic or the plastic is poured about the plate to a level which permits the plate to be at least partially captured within the liquid plastic. An additional gripping of the plastic on the plate element is obtained by the gripping bonding of the plastic onto the leg elements. The leg elements are in this case provided to develop a proper disposition and orientation of the plate, lamp, blades and other elements of the assembly in the cast plastic body but have the second purpose of anchoring the assembly into the cast polymer.
In a direct embedment of a plate and electrical assembly combination, a second element may be added to the assembly to provide a visual shield for the interior ends of the blades protruding through the plate as well as for the wires to and from the resistor and blade ends and for the resistor itself. Such a visual shield is shown in place in FIG. 11 between the bulb and plate.
The added visual element may be formed as part of or may include a semi-opague or translucent shield or diffuser which can be placed over the bulb. Use of such a shield prevents light from the bulb from producing a hot spot or glare in a forward direction through the plastic which is cast about it. A variety of the shield elements are seen in FIGS. 4, 9, and 10.
In other words where a diffuser forward of the bulb is large enough and sufficiently non-transparent it may mask the electrical parts behind and around the bulb. Where the diffuser is smaller the use of an added visual element such as 120 extending from behind the bulb but extending over the electrical parts so as to mask them from view from the front, may be necessary.
It is evident that a diffuser or shield element can conveniently be mounted on the lamp and in this way onto the lamp-plate-blade assembly. When so mounted it can be conveniently included in a casting mold so that the assembly is held by gravity in place in the mold. This is preferably with the bulb over the diffuser so that a desirable alignment of diffuser and bulb is achieved. It is not necessary that a diffuser be attached to or mounted on the bulb prior to the insertion of the assembly into a body of liquid plastic. One way in which the diffusion effect may be achieved is by casting a body of liquid plastic containing an opague pigment for diffusion of light in the portion of the total cast element which is located in front of the position to be occupied by the light itself. This is illustrated by a lower layer such as 118 of FIG. 11. By later casting another portion of the cast plastic body on top of and around the element holding the blades and lamp, the light may be distributed or spread out more effectively through a clearer back portion of plastic.
ln other words the avoidance of this hot spot and the diffusion of the light coming forward from the lamp.
may, pursuant to this invention, be achieved in a number of fashions. One such fashion is the mounting of a diffuser sleeve over the lamp itself. By a sleeve is meant a thinner tube like member extending at least part way around the glass envelope of the light source and conforming generally to it. Though such a diffuser sleeve may have light emitting portions or openings the sleeve itself should not be translucent if it is of relatively thin wall construction.
In general provision of a thin walled translucent diffuser of the thickness of the walls of tower 16 of FIG. 1 is not effective in substantially reducing the hot spot. Opague half sleeves cutting off forward transmission or a reflecting half sleeve to throw light backward are effective in significantly reducing the hot spot effect.
Another way of reducing the hot spot is by the mounting of a diffuser element on the forward side of the sub-assembly. It may also be achieved by disposing a pre-formed diffuser body in the cavity forward of where the lamp itself will be located. An effective diffuser may also be formed as a cast element where the casting is one which contains pigment to diffuse the light from the lamp. Which ever way the diffusion is achieved the novel effect attainable pursuant to the present invention is one of having a soft diffused light coming forward from the lamp combined with a distribution of light toward portions of the cast article at greater distances from the lamp.
The plastic employed in the forming of the cast portion of the guide light is preferably a polyester plastic of a high level of light transmission or defraction depending on what portion of the guide light is formed of the plastic.
Polyesters as normally used in casting of decorative articles and objects may be employed. These polyesters may have various additives included to improve some properties pertinent to the article produced.
One of the conventional additives is a coloring agent of the dye type and another is a coloring agent of the pigment type. To obtain the best decorative effects, combinations of dyes and of pigments may be employed.
One of the materials with which polyester is highly compatible is polystyrene. Polystyrene monomer may 10 be employed in thinning the liquid polyester polymer prior to pouring into the mold for casting to a solid.
Further, products made of polystyrene bond and adhere very well to the polyester which is poured about an article formed of polystyrene.
One of the articles produced according to the present invention is a low level lighting lamp article having molded polystyrene embedding the held ends of the power blades, the electrical connections, the resistor and glow lamp, and having a cast polyester bonded to the embedding polystyrene.
Another article made pursuant to the present invention is an article having power blades emerging from a pre-formed small plate-like piece of a polymer such as polystyrene and having blades extending through openings in the polystyrene, having electrical connections to the blades connecting with a glow lamp through a resistor, and having these parts and at least a portion of the polymer plate embedded within a cast polyester housing or enclosure.
The embedment of a glow lamp into cast polymer is done partly to improve the distribution of light emitted from the glow lamp.
In other words one of the features of the articles produced according to the present invention is that of having the surface of a bulb directly and immediately in contact with the polymer through which the light is to be transmitted.
The diffusion or transmission (or distribution) of light through and from the article produced pursuant to the present invention may be enhanced by providing a rear reflecting surface to throw light which would normally leave through the rear of the product and be incident on the wall proximate the rear of the product back into a diffuser portion of the product. By use of a rear reflector the light which would thus escape to the rear may be reflected back into the product and give an appearance of a higher level of illumination in the diffuser as well as an optically enhanced appearance.
As used herein the term hot spot and similar terms means that there is a high contrast in the level of light over a short lateral distance of the decorative surface of the article and that this high contrast region is generally circular or of similar closed geometric form and extending over a relatively small portion of the total surface of the diffuser visible from one point by a viewer.
Preferably the article provided by this invention has a greater height and width than depth and the light source is located generally centrally of the decorative difiuser thereof. In other words the hot spot as well as the ring or high contrast of light intensity which surrounds it is likely to occur roughly toward the center of the decorative diffuser which is not formed with the advantageous construction provided pursuant to this invention. The cast decorative diffuser of this invention has less transparency in portions more remote from the light source.
Moreover as described also in copending application Ser. No. 186,318 filed Oct. 4, 1971 the less transparent portions are preferably disposed forward of the light source, that is, in the direction from which the diffuser is likely to be viewed and the more transparent portions preferably extend out from the light source toward the outer edges of the diffuser.
Added decorative effects may be achieved by employing a product of this invention with a cast resin re- 1 1 ceptacle plate article as described in applications Ser. No. 186,150 and 186,152 both filed Sept. 30, 1971.
Curing of the polyester resin of articles disclosed herein may be accomplished by methods known in the art. Improved curing technique such as that described in the article RF Curing of Cast Polyester Parts appearing at page 60 of the July 1971 issue of Modern Plastics, a publication of McGraw-Hill Company of New York, may also be employed.
What is claimed is: l. A decorative low level lighting article, said article comprising, a source of light of low heat emission, a pair of power blades, electrical connecting means for connecting said source of light to said pair of power blades, molded plastic, said molded plastic embedding said electrical connecting means, at least partially embedding said source of light, and partially embedding said pair of power blades, a cast decorative diffuser and said diffuser at least partially embedding said molded plastic and being disposed to receive light passing through said molded plastic, and a first portion of said diffuser proximate said source of light being less than transparent to light of said source,
and a second portion of said diffuser more remote than said first portion from said source of light being more transparent than said first portion of light of said source.
2. The article of claim I wherein said source of light is at least partially embedded in a cast layer of said plastic of higher light transmission than other portions of said diffuser.
3. The article of claim 1 wherein the depth of said diffuser is less than the width or height thereof.
4. The article of claim 1 wherein said source of light is elongated and the long dimension thereof is generally normal to the smallest dimension of said diffuser.
S. The article of claim I wherein said source of light is a glow lamp and said electrical connecting means includes a resistor.
6. The article of claim 1 wherein the outer edges of said diffuser are shaped to refract light.
7. The article of claim 1 wherein a surface, reflective to the light of said source, is disposed over the umembedded portion of said source of light to reflect light into said diffuser.