Abstract:
A light emitting electric toothbrush and method therefore is disclosed which is intended for use by children, is comprised of a robust high-strength, plastic construction, and employs both light and vibration to assist in the development of suitable dental hygiene skills. In its most fundamental embodiment, the light emitting electric toothbrush comprises a construction including a handle having a bottom end and a top end and a toothbrush shaft mounted to the top end of the handle. The brush shaft is comprised of a plastic resin including a fluorescent colored light refractive additive for optimizing light transmission through the brush shaft. A high intensity light source is mounted within the top end of the handle for generating light and a domed-shaped optical lens is positioned over the high intensity light source for directing the generated light into the brush shaft. Finally, a switched electrical source is included for energizing the light source and the generated light therefrom creates a glowing illumination in the brush shaft for illuminating a dental cavity of a person during brushing of the teeth. In a preferred embodiment, the toothbrush also includes a vibrating motor mounted within the handle for causing the brush shaft to vibrate. The vibrating motor is also energized by the switched electrical source simultaneously with the light source.

Description:
This application claims the benefit of U.S. Provisional Application Ser. No. 60/117,731, filed Jan. 29, 1999. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to dental hygiene. More specifically, the present invention relates to a child&#39;s electrical powered toothbrush having an ergonomically sculpted handle, and which projects light and vibrations along a fluorescent-accented brush head to provide improved lighting in and brushing of the oral cavity and to encourage children to practice dental hygiene. 
     2. Background of the Invention 
     The best prevention against dental decay and gum disease is a thorough brushing of the teeth and gums following each meal. This action helps to eliminate the plaque buildup that can lead to dental problems. Notwithstanding most everyone in advanced societies possesses a toothbrush, dental cavities or tooth decay and periodontal disease remain a prevalent problem. This fact is especially true among children who tend to dislike the chore of brushing their teeth and may do it improperly or irregularly. Improper dental care can also be attributed to not brushing for a sufficient duration of time, and/or not being able to see plaque or food buildup for effective removal. The cleanliness of toothbrushes is also an issue if the toothbrushes are stored in a horizontal position where the bristles can come into contact with germs and bacteria. Further, dental professionals recommend that toothbrushes be replaced every three-to-six months when the bristles become worn. 
     The prior art is directed to methods and apparatus for battery operated toothbrushes for use in dental hygiene. Battery operated toothbrushes have been known in the art for assisting individuals in dental cleaning. Many examples of the battery operated toothbrushes are available and several will be briefly discussed at this time. 
     In a first example, a dental cleaning apparatus has been known which discloses a toothbrush with a light source located within the brush head or handle which emits radiation having a wavelength of 3650 angstrom units. The teeth are brushed with a specially formulated dye which attaches to plaque on the teeth. After brushing, the light source is energized and in combination with a monochromatic filter causes any dye stains within the oral cavity to fluoresce. The teeth can then be rebrushed until the plaque is removed. The dental cleaning apparatus also disclosed the use of a vibrating toothbrush. In a second example, a training apparatus for brushing teeth included a sound emitting device and/or a light emitting device provided in the stem of a toothbrush. The sound and/or light emitting devices were activated by brushing movement of the training apparatus. An electro-conductive movable piece contacted an electrode to complete an electrical circuit which resulted in the generation of the sound or light emitted from the stem of the toothbrush. 
     In another example, a toothbrush included optical fiber bristles extending longitudinally through the handle portion thereof. The optical fiber bristles were then turned upwardly at the head end of the toothbrush to form the toothbrushing bristles. A bulb end of a flash light was axially connected to the end of the handle of the toothbrush for injecting light into the ends of the optical fibers. The light was then transmitted to the distal end of the fiber bristles at a right angle resulting in loss of much of the transmitted light. Another example discloses an optical toothbrush used for medical treatment including a plurality of narrow fibers connected to a light generating device and extending through a base of the toothbrush. The narrow fibers are bent to form an L-shape and project outward from the base to form a brush. Light emitted from the light generating device is guided into each narrow fiber at its base and projected through the brush tips. 
     Yet another example discloses a toothbrush with externally illuminated bristles which includes a tubular handle with a shoulder having a light bulb mounted therein. The bulb projects a beam of light across open space onto the external surfaces of the bristles, teeth and plaque when in use. An externally mounted switch used to energize the light bulb is compressed when the toothbrush is held in the brushing position. In a final example, an illuminated toothbrush teaches a light source inserted into a socket at the end of the toothbrush handle for the purpose of illuminating the ends of the filaments. Light emitted from the light source is transmitted by the filaments, a clear plastic toothbrush handle, and the head of the toothbrush. The light from the light source then enters the individual filaments of the respective brush tufts through the bite portion and glows at the end surfaces of the filaments. 
     The battery operated toothbrushes of the prior art have also been known to incorporate bow spring triggers, high intensity light sources, replaceable toothbrush heads, push-to-operate activation buttons, toothbrush handles comprised of clear resin, and recessed light sources. 
     Thus, there is a need in the art for a light emitting vibrating electrical powered toothbrush intended exclusively for use by children and including a ergonomically-sculpted handle fashioned in the shape of a fantasy-type character having a high intensity light source combined with a vibrating source for projecting light through and vibrations along a fluorescent-accented shaft and brush head to provide improved lighting of the oral cavity and brushing of the teeth and to encourage children to practice dental hygiene. 
     SUMMARY OF THE INVENTION 
     Briefly, and in general terms, the present invention provides a new and improved light emitting electric toothbrush typically used by children during a dental hygiene training phase under the supervision of an adult and prior to their having developed the motor skills necessary to properly brush their teeth. The novel and non-obvious light emitting electric toothbrush exhibits a handle with a toothbrush shaft and brush head mounted thereon. The handle includes an ergonomic design intended for a child&#39;s hand and is sculpted in the shape of a fantasy-type character such as, for example, a dragon. The handle can be formed from Acrylonitrile Butabiene Styrene (ABS) and the toothbrush shaft and brush head can be fashioned from a clear plastic light carrying resin combined with a fluorescent-colored light refractive additive which serves to uniformly fill and transmit light throughout the toothbrush shaft and head. 
     The inventive light emitting electric toothbrush is battery operated and includes a high luminous intensity light source located in the end of the handle. The light source projects light into a replaceable, transparent, colored toothbrush shaft and brush head. It is the toothbrush shaft and brush head that contains the specially formulated light transmitting material (i.e., the fluorescent-colored light refractive additive). A switch located on the handle of the toothbrush is pressed to activate the battery operated circuitry that simultaneously energizes the light source and a vibrating motor employed to cause the toothbrush shaft and brush head to vibrate. The sculpted, ergonomically designed toothbrush handle ensures a more secure grasp and a keen visual interest by children. Further, the vibrating toothbrush head includes thin conventional bristles for improved cleaning action and plaque removal. The high intensity light source creates a glowing illumination of the entire mouth and teeth which results in improved cleaning of the teeth and a fun visual experience for children. The toothbrush stands on its flat base to be stored upright to ensure cleanliness of the bristles. The brush head is removable from the toothbrush handle and can be replaced with a duplicate brush head. 
     The present invention is generally directed to a light emitting electric toothbrush for use by children, is comprised of a robust high-strength, plastic construction, and employs both light and vibration to assist in the development of suitable dental hygiene skills. In its most fundamental embodiment, the light emitting electric toothbrush comprises a construction including a handle having a bottom end and a top end and a toothbrush shaft mounted to the top end of the handle. The brush shaft is comprised of a plastic resin including a fluorescent colored light refractive additive for optimizing light transmission through the brush shaft. A high intensity light source is mounted within the top end of the handle for generating light and a domed-shaped optical lens is positioned over the high intensity light source for directing the generated light into the brush shaft. Finally, a switched electrical source is included for energizing the light source and the generated light therefrom creates a glowing illumination in the brush shaft for illuminating a dental cavity of a person during brushing of the teeth. 
     In a preferred embodiment, the toothbrush also includes a vibrating motor mounted within the handle for causing the brush shaft to vibrate. The motor is also energized by the switched electrical source simultaneously with the light source. Further, the vibrating brush head is angled and contoured to maximize the light transmission therethrough. The brush shaft also includes an interlocking receptacle that cooperates with a protuberance formed on a lamp holder molded to the top end of the ergonomically designed handle. The interlocking receptacle includes a groove formed in the domed-shaped optical lens which receives the protuberance formed on the handle. The interlocking receptacle enables the toothbrush shaft to be installed on and removed from the ergonomically designed handle. Finally, the power supply for the battery operated toothbrush is enclosed in a locked compartment located within the flat bottom end of the handle which is accessible for changing batteries as required. 
     These and other objects and advantages of the present invention will become apparent from the following more detailed description, taken in conjunction with the accompanying drawings which illustrate the invention, by way of example. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of a light emitting electric toothbrush of the present invention showing a fluorescent-accented shaft and brush head mounted upon a lamp holder extending from a sculpted fantasy-type character that forms an ergonomically-designed handle of the toothbrush. 
     FIG. 2 is a front elevational view of the light emitting electric toothbrush of FIG. 1 showing the sculpted handle, the lamp holder, an on-off switch, the fluorescent-accented shaft and brush head, and a flat base. 
     FIG. 3 is a rear elevational view of the light emitting electric toothbrush of FIG. 1 showing the back side of the ergonomically-designed sculpted handle, the lamp holder, the fluorescent-accented shaft and brush head, and the flat base. 
     FIG. 4 is a left side elevational view of the light emitting electric toothbrush of FIG. 1 showing the lamp holder positioned beneath the fluorescent-accented shaft and brush head, the flat base, and the left side of the sculpted handle, the right side being a mirror image thereof. 
     FIG. 5 is a top planar view of the light emitting electric toothbrush of FIG. 1 showing the top of a high intensity lamp and the lamp holder mounted above the ergonomically-designed sculpted handle. 
     FIG. 6 is a bottom planar view of the light emitting electric toothbrush of FIG. 1 showing the flat base and a removable battery door for providing access to a battery compartment. 
     FIG. 7 is a cross-sectional view of the light emitting electric toothbrush of FIG. 1 taken along line  7 — 7  of FIG. 2 showing the interior of the sculpted handle including the battery compartment, the on-off switch, a vibrating motor, the lamp holder, the high intensity lamp, and the fluorescent accented shaft and brush head exploded away from the sculpted handle. 
     FIG. 8 is an enlarged cross-sectional view of the light emitting electric toothbrush of FIG. 1 taken along line  8 — 8  of FIG. 7 showing a groove formed within a sidewall of a domed lens of the fluorescent-accented shaft and brush head for receiving a nipple formed on the exterior of the lamp holder for locking the brush head to the sculpted handle. 
     FIG. 9 is an enlarged partial view of the light emitting electric toothbrush of FIG. 1 showing the high intensity light source and lamp holder fitted inside the domed lens of the fluorescent-accented shaft, the components locked together with the groove and nipple attachment mechanism of FIG.  8 . 
     FIG. 10 is a schematic diagram of the light emitting electric toothbrush of FIG. 1 showing the electrical components including a Direct Current (DC) power supply, the on-off switch, the high intensity lamp and vibrating motor wired in parallel, and a resistive component in line with the vibrating motor. 
    
    
     DESCRIPTION OF THE INVENTION 
     The present invention is a light emitting electric toothbrush  100  and method specifically designed for use by children during their dental hygiene training phase. The toothbrush  100  employs both light transmission into an oral cavity of a person (not shown) and vibration along the longitudinal axis of a brushing mechanism to assist children in visually inspecting and brushing their teeth. The toothbrush  100  is particularly useful for instructing children in the procedures of dental hygiene by requiring them to utilize both visual and tactile senses prior to their development of the motor skills necessary to execute a thorough brushing. 
     A preferred embodiment of the light emitting electric toothbrush  100  of the present invention is best shown in FIGS. 1-4. The toothbrush  100  has several main components including a handle  102  and a brushing mechanism comprising a toothbrush shaft  104  and a brush head  106  as shown in FIGS. 1 and 2. The handle  102  is ergonomically-designed for use by children, i.e., designed for little hands. To promote the interest of children in the toothbrush  100  and thus encourage them to practice dental hygiene, the handle  102  can be sculpted into a fantasy-type character that cooperates with the ergonomic design. Any suitable fantasy-type character can be incorporated into the present invention. The preferred embodiment of the present invention employs a multi-colored smiling dragon intended to attract the attention of small children. Mounted above the sculpted handle  102  of the light emitting electric toothbrush  100  is the toothbrush shaft  104  having the brush head  106  positioned at the top thereof as is clearly shown in FIGS. 1-4. The toothbrush shaft  104  and the brush head  106  are integrally connected and are disconnectively attached to the handle  102  as shown in the exploded view of FIG.  7 . 
     The following is a description of the ergonomically designed handle  102  of the present invention. Notwithstanding the exterior cosmetic sculpting selected for the particular toothbrush  100 , the handle  102  includes a front body portion  108  and a rear body portion  110  as is shown in FIG.  4 . Both the front body portion  108  and the rear body portion  110  are fashioned by plastic injection molding from a suitable material such as Acrylonitrile Butabiene Styrene (hereinafter “ABS”). Molded to the top surface of the front body portion  108  is a front upward concave extension  112 . Likewise, molded to the top surface of the rear body portion  110  is a mating rear upward concave extension  114  as is best shown in FIG.  7 . Thereafter, the front body portion  108  including the front upward concave extension  112  and the rear body portion  110  including the rear upward concave extension  114  are ultrasonically bonded together along an interface line  116  as best shown in FIG.  4 . Thus the front body portion  108  and the rear body portion  110  are intended to be permanently sealed. 
     The mating of the front upward concave extension  112  to the rear upward concave extension  114  provides a generally upward extending, truncated, conical shape which serves as a lamp holder  118  as shown in FIG. 9. A high intensity, vacuum bi-pin lamp  120  incorporated into a T1 envelope is mounted in the lamp holder  118 . The high intensity lamp  120  is positioned within the lamp holder  118  so that 2.5 millimeters (mm) of the lamp  120  extend upward and outward from the lamp holder  118  as shown in FIGS. 7 and 9. This positioning of the lamp  120  within the lamp holder  118  ensures that an adequate amount of light will be (a) projected into a domed-shaped optical lens  122  located in the bottom of the toothbrush shaft  104  and also (b) projected into the brush shaft  104  and the brush head  106 . The high intensity lamp  120  preferably should be rated at 3.0 volts drawing within the range of aproximately 0.330-to-0.450 amperes maximum and include a C2R filament, an MSCP (Measurement of Light in Mil Candle Power) of 1.02 and have a life expectancy of a minimum of 60 life hours at full load before the C2R filament burns out. The high intensity lamp  120  is manufactured by and available from Precision Lighting or Whamco Lighting, both of Santa Rosa, Calif. 
     A penetration  124  is formed through the front body portion  108  of the ergonomically designed handle  102  to accommodate a switch cap  126  as best shown in FIG. 7 but also shown in FIGS. 1,  2  and  4 . The switch cap  126  is located over an actuating plunger  128  of a two-position (on/off) button switch  130  that is mounted to structural ribbing  132  molded to the inside surfaces of the front body portion  108  and rear body portion  110  (see FIG.  7 ). The structural ribbing  132  is comprised of the same ABS material as the remainder of the handle  102 . The switch cap  126  and the button switch  130  including associated brackets are mounted to the structural ribbing  132  by any suitable means such as, for example, by screws. The switch cap  126  is injection molded and comprised of a soft material such as silicone or synthetic rubber to provide a comfortable feel and a watertight seal over the two-position button switch  130 . The two-position button switch  130  serves to apply electrical potential from a direct current (d.c.) power supply  134  to the high intensity lamp  120  and to a vibrating motor  136 . The vibrating motor  136  is also located within the handle  102  and is also supported by and fastened to the structural ribbing  132  molded to the inside surfaces of the handle  102 . 
     The ergonomically designed handle  102  includes a flat bottom  138  as shown in FIGS. 6 and 7 which enables the light emitting electric toothbrush  100  to stand upright for storage. The flat bottom  138  also assists in maintaining cleanliness in the brush head  106  since there is a higher probability of avoiding exposure to debris and bacteria when the toothbrush  100  is in the vertical position. The d.c. power supply  134  comprised of two AAA cell alkaline batteries (each generating 1.5 volts d.c.) is located within a battery compartment  140  inside the ergonomically designed handle  102  as is best shown in FIG.  7 . The battery compartment  140  is accessible through a hinged battery door  142  formed in the flat bottom  138  best shown in FIG.  6 . The battery door  142  is injection molded from a rigid material such as, for example, ABS and includes two ABS pins  144  formed on the inside of the battery door  142  for securing a battery contact plate  146  thereto as shown in FIG.  7 . The battery contact plate  146  includes a pair of penetrations (not shown) through which the two ABS pins  144  pass. Once the battery contact plate  146  is positioned over the ABS pins  144 , the two ABS pins  144  formed on the inside of the battery door  142  are melted down in a typical heat staking operation as is known in the art. This procedure ensures that the battery contact plate  146  is securely held in position. 
     The battery door  142  is hinged on one end thereof and slides into a pair of slots  147  located in the front body portion  108  and swings to close onto the rear body portion  110 . A door securing screw  148  is employed to secure the hinged battery door  142  to a threaded body boss  149  molded to the rear body portion  110  to prevent children from accessing the battery compartment  140 . In particular, the door securing screw  148  is captivated within the hinged battery door  142  as shown in FIG.  7 . The hinged battery door  142  includes a penetration  150  formed therein through which the door securing screw  148  passes. The screw  148  is press-fitted through the penetration  150  in the battery door  142 . The penetration  150  in the battery door  142  has a diameter smaller than the diameter of the threads but larger than the diameter of the shaft of the door securing screw  148  to enable movement of the screw  148 . This design enables the screw  148  to secure the closure of the battery door  142  but when the threads are disengaged, the door securing screw  148  will remain captured within the penetration  150  of the battery door  142 . This design prevents the door securing screw  148  from becoming a “small part” hazard to small children. Removal of the door securing screw  148  requires forcing the screw  148  back through the penetration  150 . 
     The interior construction of the ergonomically designed handle  102  is best shown in FIG.  7 . The ABS structural ribbing  132  is clearly shown for supporting the d.c. power supply  134 , the two-position button switch  130 , and the vibrating motor  136 . The electrical circuitry of the toothbrush  100  is energized by the two AAA cell alkaline batteries of the power supply  134  generating a total of 3.0 volts. Mounted directly above the battery compartment  140  is a positive contact plate  151  and a negative contact plate  152 . The positive contact plate  151  is in electrical communication with the positive terminal of a first of the two AAA cell alkaline batteries of the power supply  134 . Likewise, negative contact plate  152  is in electrical communication with the negative terminal of a second of the two AAA cell alkaline batteries of the power supply  134 . In addition, the battery contact plate  146  shown at the bottom of the battery compartment  140  in FIG. 7 electrically connects the negative terminal of the first AAA cell alkaline battery to the positive terminal of the second AAA cell alkaline battery. Thus, the two AAA cell alkaline batteries of the power supply  134 , the positive contact plate  151 , the negative contact plate  152  and the battery contact plate  146  form a series connection as is shown in FIG.  10 . 
     The two position button switch  130  is clearly shown mounted to the structural ribbing  132  in FIG.  7 . The actuating plunger  128  extending from the switch  130  is spring-loaded and can be operated by pressing on the switch cap  126 . The switch  130  is clearly shown in FIG. 10 as being connected in series with the two AAA cell alkaline batteries of the power supply  134 . Thus, operation of the switch  130  will apply electrical power to the high intensity lamp  120  and the vibrating motor  136 . The two position button switch  130  can be any suitable two position, spring-loaded, press-to-operate switch having contacts that are rated to provide electrical power to the high intensity lamp  120  and to the vibrating motor  136 , simultaneously. It is clear from FIG. 10 that the high intensity lamp  120  and the vibrating motor  136  are parallel connected so that the 3.0 volt potential generated by the power supply  134  is applied to both electrical loads. Thus, the voltage between potential points  154  and  156  shown on FIG. 10 is 3.0 volts. The high intensity lamp  120  is rated at 3.0 volts drawing from 0.330-to-0.450 amperes and thus is connected directly across potential points  154  and  156 . 
     The vibrating motor  136  can be, for example, a Mabuchi motor having a variable input voltage ranging from (1.5-3.0) volts d.c. depending upon the desired motor speed. This motor is manufactured by Mabuchi Motors Ltd. in Japan and can be ordered using stock number #FA-130RA-2270. As can be seen in FIG. 7, the vibrating motor  136  is mounted within and supported by the structural ribbing  132 . It is noted that an electrical resistor  158  is placed in series with the vibrating motor  136  to increase the resistive load therein. The higher resistive load results in a larger voltage drop in the parallel leg containing the vibrating motor  136 . If the electrical resistor  158  is properly sized, the voltage potential across the motor can be dropped from 3.0 volts d.c. to 1.5 volts d.c. This voltage reduction can be accomplished when the electrical resistor  158  has a resistance of 5.1 ohm for dissipating ¼ watt of power. This example voltage reduction reduces the speed of the vibrating motor to 7000 RPM. Thus, it can be seen that when the two position button switch  130  is actuated, the high intensity lamp  120  and the vibrating motor  136  are energized simultaneously. 
     The vibrating motor  136  includes an output shaft  160  as shown in FIGS. 7 and 10. The output shaft  160  rotates at the speed determined by the electrical resistor  158 , for example, 7000 RPM. Mounted upon the output shaft  160  of the vibrating motor  136  is a cam cylinder  162  as shown in FIGS. 7 and 10. The cam cylinder  162  is mounted off-center and thus causes the output shaft  160  to wobble during rotary motion. Because the output shaft  160  of the motor  136  rotates at a high frequency, i.e., for example, 7000 RPM, a high frequency vibration in the output shaft  160  results. The motor  136 , which vibrates because of the off-center cam cylinder  162 , transfers the vibrations to the structural ribbing  132 , the handle  102 , the brush shaft  104  and the brush head  106 . Thus, the vibrations created within the handle  102  are transferred to the brush head  106  to assist in cleaning the teeth of the child. 
     It is noted that the handle  102  is ergonomically designed especially for use by children. In effect, this statement means that the exterior design of the front body portion  108  and the rear body portion  110  are sculpted to fit small hands such as those of children. In particular, FIGS. 1-4 illustrate the overall shape of the handle  102 . FIG. 4 is a side elevational view which clearly shows how the front body portion  108  is somewhat convex in shape and the rear body portion  110  is somewhat concave in shape. Because of this design, the concave rear body portion  110  fits conveniently into the palm of a small hand. Likewise, the convex front body portion  108  of the handle  102  is conveniently shaped for wrapping the fingers of a small hand thereabout. Additionally, the switch cap  126  is positioned on the front body portion  108  so that it can be conveniently pressed by the fingers of the child for actuating the two position button switch  130 . 
     The toothbrush mechanism will now be described. The entire toothbrush mechanism is removable from the handle  102  and is comprised of the brush shaft  104 , the brush head  106  and the domed-shaped optical lens  122 . The brush shaft  104  and brush head  106  are injection molded into an integral unit from a custom mixed polycarbonate material which is a clear plastic light carrying resin identified as Novarex® #7022IR. This material is available from Raycon Industries, Inc. of Sunnyvale, Calif. The Novarex® material has a 22 melt index (referring to the rating for injection molding conditions for heat and pressure factors) and contains a translucent, fluorescent colored additive  164  employed for enhanced light transmission and fill of the clear plastic resin of which the brush shaft  104  and the brush head  106  are comprised. In this situation, the term “fill” means uniform light consistent among the surfaces visualized. 
     The fluorescent colored additive  164  incorporated into the Novarex® #7022IR material functions as a refracting material for deflecting and carrying light throughout the brush shaft  104  and brush head  106  and to fill the contours thereof. Thus, the fluorescent colored additive  164  reflects and refracts light and transmits the light to the surfaces of the brush shaft  104  and brush head  106 . The Novarex® material contains a 7% concentration of the fluorescent colored additive  164  for enhancing the light transmission through the light carrying resin polycarbonate material of the brush shaft  104  and brush head  106 . The fluorescent colored additive  164  can be obtained in a plurality of colors from Color Science in Santa Ana, Calif. The stock number for the additive  164  is Color Science #CS1Y704C. In the preferred embodiment of the present invention, the color selected for the fluorescent colored additive  164  was yellow. However, any color of fluorescent colored additive  164  could be utilized as the refracting material. 
     The brush shaft  104  and brush head  106  are specially designed to include contours and angles that enhance the transmission of light for carrying the light rays from the high intensity lamp  120  to the top  166  of the brush head  106  and angled to reach the back teeth. The aforementioned contours and angles incorporated into the brush shaft  104  can be described as reflecting fillets and radii that enhance light transmission. The contours and angles function as defined reflective and refractive surfaces in optical optimum geometry resulting in uniform light fill of the brush shaft  104  and brush head  106 . The fillets are surfaces with specific radii that reflect light transmission. An optimal condition for reflecting light is created by the use of radii with minimum angles. It is not a measurement that creates the effect of light fill and consistency but a condition that is created. The goal is to reduce or eliminate sharp bends. Thus, the larger the angle and the radii, the better the condition for light fill and consistency. Light bounces into and out of the fillets filling the surfaces visualized. 
     A plurality of bristles  168  are anchored in a known manner to the brush head  106  as is shown in FIGS. 1-4 and  7 . The brush bristles  168  are conventional, thin filament bristles having a diameter of approximately 0.15 mm and comprised of a clear nylon material. Formed in the bottom of the brush shaft  104  (and opposite to the end of the brush head  106 ) is the domed-shaped optical lens  122  shown in FIGS. 7 and 9. The domed-shaped optical lens  122  is a geometric feature of the molded brush shaft  104 . The lens  122  is comprised of Novarex® #7022IR polycarbonate material and is a highly polished optical lens. In particular, the lens  122  includes a highly polished SPI/SPE #1 finish which refers to the surface finish on the mold utilized to form the lens  122 . As a consequence of the use of this mold rating, the resulting domed-shaped optical lens  122  will be highly polished. The SPI/SPE #1 rating is important as it is a measurement of the surface irregularities measured in microns. The SPI/SPE #1 rating (also known as micro finish) is an industry standard established by the Mold Makers/Engineers Society of America. 
     The domed-shaped optical lens  122  is typically referred to as a concave single plano lens. The highly polished surface on the lens  122  creates an optical surface for refracting light rays. Thus, the function of the optical lens  122  is to collect the scattered light rays from the high intensity light source  120  and to direct the light rays into the toothbrush shaft  104  and brush head  106 . The illustration in FIG. 9 shows the proximity of the light source  120  to the optical lens  122 . The highly polished surface on the lens  122  in combination with the light fill characteristics of the fluorescent colored additive  164  result in improved light fill, light transmission and full glowing illumination of the brush shaft  104  and brush head  106 . Consequently, the brush shaft  104  and the brush head  106  are illuminated by the light source  120  and the optical lens  122  so as to light up the dental cavity of the child. This visual assistance helps the child in brushing their teeth and also creates a fun visual experience. 
     The brush shaft  104  is mechanically connected to the lamp holder  118  formed at the upper end of the ergonomically designed handle  102  as is best shown in FIGS. 7 and 9. Molded into the bottom of the brush shaft  104  just beneath the highly polished domed-shaped optical lens  122  is an interlocking receptacle  172 . The interlocking receptacle  172  includes a groove  174  cut or formed into a sidewall  176  of the conical opening associated with the domed-shaped optical lens  122  as is shown in FIG.  7 . The groove  174  is formed in the shape of a right angle with an opening to the groove  174  located at the bottom edge  178  of the brush shaft  104 . The groove  174  is positioned and sized to cooperate with a protuberance  180  formed on the side of the lamp holder  118  as shown in FIGS. 7,  8  and  9 . The protuberance  180  is molded from ABS onto the front upward concave extension  112  of the lamp holder  118 . 
     As shown in FIG. 7, the opening to the groove  174  formed on the bottom edge  178  of the brush shaft  104  is positioned so as to be aligned with the protuberance  180 . The groove  174  formed in the sidewall  176  is forced down over the protuberance  180  extending from the lamp holder  118 . The protuberance  180  initially travels upward through a vertical portion of the groove  174 . Thereafter, the brush shaft,  104  or alternately the handle  102 , is rotated in the appropriate direction to force the protuberance  180  into a horizontal portion of the groove  174 . 
     FIG. 8 is a cross-sectional view taken through the lamp holder  118  but below the high intensity lamp  120  as shown in FIG.  7 . In FIG. 8, the protuberance  180  is shown (in phantom) at the top of the vertical portion of the groove  174 . Thereafter, the brush shaft  104  (or the handle  102 ) is appropriately rotated to cause the protuberance  180  to pass through the horizontal portion of the groove  174 . Eventually, the protuberance  180  reaches a stop  182  at the end of groove  174  and the brush shaft  104  is now locked to the handle  102  for forming a water tight fit. A sectional view showing the brush shaft  104  locked onto the handle  102  is shown in FIG.  9 . Removal of the brush shaft  104  from the handle  102  can be accomplished by reversing the previously described procedure. An alternative interlocking receptacle  172  could include ribbing (not shown) formed within the conical opening on the bottom edge  178  of the brush shaft  104  the cooperates with corresponding ribbing (not shown) formed on the exterior surface of the lamp holder  118 . In either scheme, an additional brushing mechanism comprising the brush shaft  104  and the brush head  106  is available for replacement when the brush bristles  168  become worn. 
     The present invention provides a solution to the problems existing heretofore by providing an easy-to-use, battery operated electric toothbrush  100  that creates a glowing illumination of the mouth to provide improved visibility of the teeth and gums for cleaning food particles therefrom. At the same time, an exciting visual effect is created by both the glow of the material and the sculpted design of the ergonomically designed handle  102  which will encourage children to want to use the toothbrush  100  more frequently. Combined with the light, the vibrating action of the plurality of bristles  168  provides improved teeth cleaning for children who have not yet developed fine motor skills. The high intensity lamp  120  is keep clean by being enclosed within the lamp holder  118  and is therefore not exposed to toothpaste buildup and water. 
     The brush shaft  104  and brush head  106  are angled and contoured for improved light fill and for reaching back teeth and contains conventional clear, thin bristles  168  for efficient cleaning. The two-position button switch  130  mounted on the handle  102  is easy to actuate and the toothbrush  100  will remain energized until the button switch  130  is pressed again to de-energize it. Thus, the child does not have to continuously press an activation switch while simultaneously attempting to brush their teeth. The toothbrush  100  is stored upright on the flat bottom  138  which minimizes exposure of the bristles  168  to germs and bacteria. The integral brush shaft  104  and brush head  106  can be discarded when the bristles  168  are worn and replaced with an additional brushing mechanism. The batteries of the d.c. power supply  134  are easily replaced by removing the securing screw  148  from the hinged battery door  142 . The securing screw  148  also serves as a safety feature by requiring adult supervision to access the power supply  134 . 
     The present invention provides additional novel advantages over other electric toothbrushes known in the art. A main advantage of the light emitting electric toothbrush  100  of the present invention is that it is intended exclusively for use by children and includes an ergonomically-designed handle  102  sculpted into the shape of a fantasy-type character to visually attract the interest of children. The toothbrush  100  includes a high intensity light source  120  combined with a vibrating motor  136  for projecting light through and vibrations along a brush shaft  104  and a brush head  106 . Both the brush shaft  104  and brush head  106  contain a translucent, fluorescent colored light refractive additive  164  to provide uniform fill and optimized light transmission therethrough for improved lighting of the oral cavity and brushing of the teeth and to encourage children to practice dental hygiene. 
     Obviously the invention is susceptible to changes and alterations without defeating its practicability. Therefore, we do not wish to be confined to the preferred embodiment shown in the drawings and described herein. Many other variations are possible, such as, the type or percentage of color additive used for the toothbrush shaft  104  and brush head  106  which can vary from as little as 2% to 25%, and the actual color may vary, such as fuchsia, green, aqua and the like. Different materials or a combination of materials may be used for the injection molding of the handle  102  and the brushing mechanism. Other additives, such as, sparkles or special effects can be added to the ABS plastic for visual and lighting effect. A different fluorescent colored additive  164  or material can be utilized in the toothbrush shaft  104  and brush head  106 . Additional lamps  120  or different types of lamps or lighting devices can be employed in the handle  102  and brushing mechanism for improved light fill and decorative effect. Sound effects could also be added to the inventive toothbrush  100 . 
     The design of the handle  102  can vary from the dragon design selected for the present invention but can also adopt other shapes or forms. Different switch mechanisms, motors, resistors and circuit components can be substituted for those appearing in the drawing Figs. The replaceable brushing mechanism and method of attachment can be changed to a threaded type interlocking receptacle  172  or eliminated entirely. Different types of batteries may also be utilized. It is within the design criteria to incorporate a rechargeable unit in combination with the d.c. power supply  134  or, in the alternative, to include appropriate circuitry to enable the use of an alternating current source. Also, additional facets or surface texture or detail may be added to the toothbrush shaft  104 , brush head  106  or handle  102  for enhancing light fill and effect. 
     While the present invention is described herein with reference to illustrative embodiments for particular applications, it should be understood that the invention is not limited thereto. Those having ordinary skill in the art and access to the teachings provided herein will recognize additional modifications, applications and embodiments within the scope thereof and additional fields in which the present invention would be of significant utility. 
     It is therefore intended by the appended claims to cover any and all such modifications, applications and embodiments within the scope of the present invention. 
     Accordingly,