DETAILED DESCRIPTION OF THE INVENTION
 The present invention provides a process for integrating a protective helmet and electroluminescent lamp to form a helmet illumination system. In addition, certain components of the illumination system may be formed together as disclosed in U.S. Pat. Ser. No. 6,203,391 of Murasko, the teachings of which are incorporated by reference herewith. The '391 patent discloses processes for forming electroluminescent signs by combining electroluminescent lamp components with a sign substrate. Further, the materials used for the EL lamp components may also include those disclosed in U.S. patent application Ser. No. 09/815,078, filed Mar. 22, 2001, for an “Electroluminescent Multiple Segment Display Device”, the teachings of which are incorporated by reference herewith.
 The helmet illumination system 100 of the present invention is shown in FIGS. 1-3. According to one embodiment, system 100 comprises a protective helmet 102 (e.g. a helmet “biscuit”), a substrate 104 affixed to protective helmet 102, and an electroluminescent lamp 106 positioned between the substrate 104 and protective helmet 102. Substrate 104 defines at least a portion of a helmet outer shell 108 such that substrate 104 and protective helmet 102 may form a complete helmet assembly 110 encasing EL lamp 106 therein. However, it is only necessary to configure substrate 104 to cover areas of helmet 102 that are desired to be illuminated by EL lamp 106, such that another substrate section not having illuminated areas may combined with substrate 104 to form a complete helmet outer shell 108.
 Protective helmet 102 may be of any type of helmet, such as a bicycle helmet, construction helmet, climbing helmet, general safety helmet, and the like, and may be made of materials such as styrofoam and other impact absorbing materials. In the exemplary embodiment shown in FIGS. 1-3, the helmet is a bicycle helmet. Protective helmet 102 has an interior surface (not shown) that is configured to generally rest upon a head of a helmet wearer, and an exterior surface 112 to which substrate 104 is affixed. A power source 114, such as a battery, is preferably disposed within a recessed portion 116 of protective helmet 102 at a rearward section 118 of the helmet to supply electrical energy to electroluminescent lamp 106 for illumination. A battery compartment 120 having an access door 122 may be positioned in recessed portion 116 to house the battery. Additionally, a control switch 124 may be mounted on the battery compartment 120 to control electrical energy discharge from power source 114 to EL lamp 106. Switch 124 may be an on/off switch, a timer switch with a strobe feature to turn the EL lamp illumination on and off every few seconds. Optionally, a controller (not pictured), such as a microprocessor and memory, may be electrically connected to power source 114 to vary the illumination pattern of EL lamp 106 by, for example, illuminating certain regions of EL lamp 106 at specific time intervals (i.e. successively illuminating the letters “B-I-K-E-R” formed on the lamp), or by varying the intensity of illumination, and may be configured to create a moving light image.
 Substrate 104 is typically a thin, planar structure, and forms the base layer upon which electroluminescent lamp component layers are formed, and also serves as at least a portion of the helmet outer shell 108 to protect EL lamp 106 from exposure to environmental conditions. Substrate 104 has an outer surface 126 and an inner surface 128 which faces and overlies helmet exterior surface 112. Light-transmissive materials (i.e. transparent or translucent materials), preferably heat stable yet deformable polycarbonate-type plastic, make up at least a portion of substrate 104 through which the illumination of EL lamp 106 is to be viewed. The materials chosen for the substrate should allow the substrate 104 to be formed to overlie helmet exterior surface 112, and be sufficiently durable (i.e. impact and scratch resistant, chemically stable, etc.) as to protect EL lamp 106 from exposure to environmental conditions. The light-transmissive properties of the substrate 104 allow the viewing of the illumination of EL lamp 106 through substrate 104. The thickness of substrate 104 should range from about 7 microns to about 15 microns (1 micron=1×10−6 meters). Substrate 104 may have background layer formed thereon as a display or image (e.g., wording, logos, icons, etc.) by, for example, colored printable inks. The background layer may be either light-transmissive or optically opaque so long as a light-transmissive viewing area 130 remains on substrate 104 such that the illumination of EL lamp 106 can be viewed therethrough.
 The component layers of electroluminescent lamp 106 are preferably formed in a reverse build on substrate inner surface 128 in a manner similar to that taught in the '391 patent. In this arrangement, EL lamp 106 comprises a transparent front electrode formed on substrate inner surface 128, a light emitting layer formed on the transparent front electrode, if an electroluminescent phosphor is used for the light emitting layer, a dielectric layer formed on the light emitting layer, and a rear electrode formed on the light emitting layer, or if the optional dielectric layer is provided, the rear electrode is formed on such dielectric layer. Each of the components of EL lamp 106 may be successively applied onto substrate 104 by a variety of means, including stenciling, flat coating, brushing, rolling, and spraying, but preferably are printed onto the substrate by screen or ink jet printing. The EL lamp components may be made from the following materials: the transparent front electrode may be fabricated from organics, such as polyaniline, polypyrrole, poly-phenyleneamine-imine, and polyethylene-dioxithiophene, or inorganics, such as indium-tin-oxide; the light emitting layer may be fabricated from organics, such as light-emitting polymers/organic light emitting diodes, or non-organics, such as phosphor layer of electroluminescent particles, e.g., zinc sulfide doped with copper or manganese which are dispersed in a polymeric binder; the dielectric layer of high dielectric constant material such as barium titanate; and the rear electrode may be fabricated from organics, such as polyaniline, polypyrrole, poly-phenyleneamine-imine, and polyethylene-dioxithiophene, which is available under the trade name “Orgacon” from Agfa Corp. of Ridgefield Park, N.J., or inorganics, such as silver or carbon particles dispersed in a polymeric ink. Preferably, to minimize the drain of electrical energy from power source 114 while maintaining adequate illumination levels for the EL lamp 106, the light emitting layer is made of a light emitting polymer that requires low voltage for operation, typically about 10 volts or less. Optionally, the background layer formed as a display or image may be formed onto substrate inner surface 128 prior to EL lamp 106 being formed thereon. Additionally, illuminated images can be formed by positioning the light emitting layer of EL lamp 106 in the form of such images.
 In an alternative embodiment, electroluminescent lamp 106 could be formed on outer surface 126 of substrate 104 such that illumination emanating from EL lamp 106 would not have to travel through substrate 104 to be viewed. Thus, substrate 104 would not have to be light-transmissive, but would be formed with a reserved area. The reserved area is generally a location on substrate 104 which is image-free, or where it is unnecessary to view a display or image on substrate 104 that may be blocked by placement of EL lamp 106 thereon. In this way, EL lamp 106 is formed in a forward build on substrate 104 in a manner similar to that taught in the '391 patent. EL lamp 106 comprises a rear electrode formed onto substrate outer surface 126, if an electroluminescent phosphor is used for the light emitting layer, a dielectric layer formed on to the rear electrode, a light emitting layer formed on the rear electrode, or if the dielectric layer is included, the light emitting layer is formed on such dielectric layer, and a transparent front electrode layer formed on the light emitting layer. Preferably, these EL lamp components are printed onto substrate 104. A light-transmissive electrically insulative material, such as an ultraviolet coating, may be positioned to overlie EL lamp 106 to reduce the risk of electric shock by contacting electrically conductive parts of the lamp, and to prevent short circuits due to exposure to environmental conditions.
 If the light emitting layer of EL lamp 106 is an electroluminescent phosphor, and power source 114 is a DC (direct current) power source, such as a battery, then power source 114 is connected to an inverter which converts DC to AC (alternating current) power while boosting the voltage and frequency rating. The AC power is then brought to the front and rear electrode of EL lamp for illumination of the light emitting layer.
 According to one embodiment, a transparent light reflective layer is formed over substrate outer surface 126 of EL lamp 106 as taught in U.S. Pat. Ser. No. 5,552,679 of Murasko, the teachings of which are incorporated by reference herewith. The light reflective layer reflects light incident on substrate 104 from sources such as car headlights, etc., while allowing the illumination of EL lamp 106 to be viewed therethrough by an observer. The light reflective layer may be attached substrate outer surface 126 by various methods such as heat bonding or by the use of transparent adhesives.
 A set of leads 132 are formed on substrate inner surface 128 to electrically connect power source 114 to EL lamp 106 to bring electrical energy to the lamp for illumination. These leads 132 connect to the front and rear electrodes of EL lamp 106. Preferably, leads 132 comprise a front outlying electrode lead configured to substantially surround and electrically contact the transparent front electrode of EL lamp 106, and a rear electrode lead configured to electrically contact the rear electrode of EL lamp 106. Also, leads 132 are positioned to extend off of substrate 104 forming a portion of the helmet outer shell 108 to form lead tails 134 that extend to the location of the power source 114 on helmet 102 (e.g., to battery compartment 120 of helmet rearward section 118).
 FIG. 4 is a flow chart showing an exemplary sequence of steps for fabricating the helmet illumination system 100 of the present invention. At step 401, an optional background layer of a display or image may be formed onto substrate 104. For example, the background layer may comprise colored inks that are printed onto substrate 104 in a desired pattern. Such inks may be light-transmissive or optically opaque so long as a light-transmissive viewing area 130 remains on substrate 104 such that the illumination of electroluminescent lamp 106 can be viewed therethrough. According to one embodiment, viewing area 130 is an area of substrate 104 that is free of a background layer display or image.
 At step 402, electroluminescent lamp 106 is formed onto viewing area 130 of substrate inner surface 128. Preferably, the EL lamp components are successively screen printed onto viewing area 130 in the following order: the transparent front electrode on substrate inner surface 128; the light emitting layer on the transparent front electrode; if an electroluminescent phosphor is used for the light emitting layer, the dielectric layer on the light emitting layer; and the rear electrode on the light emitting layer, or if the optional dielectric layer is provided, the rear electrode is on such dielectric layer.
 At step 403, leads 132 (i.e., rear electrode lead and front outlying electrode lead) are affixed to the substrate inner surface 128 with EL lamp 106 and positioned such that when substrate 104 is formed to helmet exterior surface 112 in a later step, leads 132 extend to rearward section 118 of helmet 102 to form lead tails 134.
 Substrate 104 and EL lamp 106 formed thereon are now ready to form at least a portion of helmet outer shell 108 to be affixed to helmet exterior surface 112. At step 404, EL lamp 106 and substrate are typically a flat, sheet-like structure that need to be molded into a three-dimensional shape that mates with helmet exterior surface 112. Substrate 104 and EL lamp 106 are then placed in the frame of a vacuum form type machine, such as a Qvac model PC 2430PD of Santa Fe Springs, Calif. A mandrel mold is fabricated with peaks and valleys and includes draw depths between about 0 inches and about 24 inches. Substrate 104 is inserted into the vacuum form machine such that the substrate outer surface 126 (i.e. the surface viewable upon forming the helmet outer shell 108 integral with helmet exterior surface 112) is in a forward viewing position and EL lamp 106 formed on substrate inner surface 128 is facing down or towards a mandrel table. A mandrel form of helmet 102 is place on the vacuum table and the temperature of the oven is set in a range of at about 500 degrees to 650 degrees Fahrenheit and the dwell vacuum time is set. Preferably, the dwell time is a heat dwell ranging from about 10 to 20 seconds for a substrate of thickness of about 7 to 150 microns. However, such dwell time will vary based on the thickness of substrate 104.
 At step 405, the vacuum form machine is turned on and a cycle is run. A frame containing substrate 104 is placed over the heater and the plastic slightly deforms or sags downward and thereafter tightens up in about a 10 to 20 seconds time period. Once substrate 104 is heated for the proper length of time, substrate 104 is mechanically pulled down onto the mandrel mold which applies a vacuum pull in two places, a bottom of the vacuum form face, and through openings in the mandrel mold that allow for even pressure pull to substrate 104. Substrate 104 is then formed into the desired shape of a helmet outer shell 108 (i.e. the shape of the mandrel mold). Air pressure is then reversed through the openings utilized to create the vacuum which releases helmet outer shell 108 from the mold. Outer shell 108 is then removed and the ventilation holes for the helmet are trimmed out. The finished outer shell 108 and integral EL lamp 106 are then ready to be electrically connected to power source 114 with leads 132 and the assembly installed onto the helmet exterior surface 112.
 At step 406, the helmet outer shell assembly with EL lamp 106 formed thereon may be attached to the protective helmet 102 by any means, such as by fasteners, adhesives, or similar means, such that EL lamp 106 is positioned between substrate 104 and helmet 102.
 Thus, the helmet illumination system 100 of the present invention results in a more integrated, lower profile, and more durable illumination solution for a helmet. System 100 may be configured to reflect light incident on the helmet outer shell 108 while also illuminating in specific area. The illumination can be configured to be in varying colors and designs (wording, logos, icon) depending on the design of the light emitting layer of EL lamp 106 and the background layer formed on substrate 104. The process for fabricating the helmet illumination system 100 has the advantage of not requiring any independent wiring, because EL lamp 106 and leads 132 have been formed below the helmet outer shell 108.