fig1 a shows a typical known decorative ornament ( 1 ) as might be used to decorate a christmas tree . fig1 b shows the ornament ( 1 ) with the cap ( 4 ) and electronics assembly ( 11 ) disassembled as , for instance , would be necessary to replace the battery ( 8 ). the globe ( 2 ) has a short neck ( 3 ) which contains threads or other means to attach the globe ( 2 ) to the cap ( 4 ) ( not shown ). the electronics assembly ( 11 ) consists of a battery holder ( 6 ), a battery ( 8 ), a printed circuit board ( pcb ) ( 9 ), and a light source ( 10 ). the light source ( 10 ) is typically a light emitting diode ( led ). an extended portion ( 7 ) of the battery holder ( 6 ) is larger than the opening in the neck ( 3 ) of the globe ( 2 ). an opening ( 12 ) allows external ambient light to enter and strike a light sensing device ( 13 ). the light sensing device ( 13 ) is positioned so that relatively little of the light from the light source ( 10 ) can reach the light sensing device ( 13 ). the opening ( 12 ) would typically be covered by a transparent lens ( not shown ). creating the opening ( 12 ), the lens , and the structures needed to position the light sensing device ( 13 ) away from and shielded from the light source ( 10 ) complicates the design and add cost . referring to the cross section view of fig2 , when the cap ( 4 ) is attached to the globe ( 2 ), the extended portion ( 7 ) is captured between the globe ( 2 ) and the cap ( 4 ) and locates the electronics assembly ( 11 ) in the desired location within the globe ( 2 ). ( for simplicity , the threads used to attach the cap ( 4 ) to the globe ( 2 ) are not shown .) the extended portion ( 7 ) also prevents the electronic assembly ( 11 ) from passing through the short neck ( 3 ) and falling into the globe ( 2 ). a difficulty occurs during battery replacement since when the user unscrews the cap ( 4 ), he must then also extract the battery holder ( 6 ) from the globe ( 2 ) before he can replace the batteries , which may result in misplacing the cap ( 4 ) during battery replacement . if battery replacement is performed in an awkward location , such as on top of a ladder , needing to deal with an ornament that is in three pieces increases the likely hood a part will be dropped and possibly damaged . fig3 illustrates the illumination pattern produced by the light source ( 10 ) within the ornament ( 1 ). the light source ( 10 ), preferably an led , is generally directional with the majority of the light emitted in the directions of ray ( 14 ), ray ( 15 ), and ray ( 16 ). this directionality combined with the position of the pcb ( 9 ), which blocks light that may have been directed behind the light source ( 10 ), results in heavily shadowed portions of the globe ( 2 ) indicated by arc ( 18 ) behind a shadow line indicated by line ( 17 ). for simplicity , only a small section is shown of the shadowed area , however it will be understood that this shadowed area extends around the entire top circumference of the globe ( 2 ). if the globe ( 2 ) is generally transparent , the light emitted from the light source ( 10 ) will pass directly through the globe ( 2 ) as indicated by ray ( 14 ) and ray ( 15 ). this will result in a bright spot in the center of the globe and a very uneven illumination of the surface of the globe ( 2 ). to help achieve a more even illumination of the surface of the globe ( 2 ), a property of the globe ( 2 ) material known as haze can be increased . increased haze results in scattering of the light rays that strike the surface as indicated by ray ( 16 ) and scattered rays ( 19 ) and ( 20 ). the scattered rays ( 19 ) will continue and strike internal surfaces of the globe ( 2 ) that would not otherwise be illuminated . however , in practice , increasing the haze to the point where the entire globe ( 2 ) is illuminated evenly results in a large portion of the light never passing outside the globe ( 2 ). this results in a very dim ornament when the light source intensity is set to levels that will achieve an acceptable battery life . fig4 a and 4b show the ornament of the present invention . fig4 a shows the ornament when the decorative cap is installed . fig4 b shows the ornament with the decorative cap removed as would be necessary to replace the battery . the battery holder ( 6 ) is permanently attached to the decorative cap ( 4 ) so that the entire electronics assembly ( 11 ) is removed as one piece when the decorative cap ( 4 ) is removed thus minimizing the number of parts that must be handled during battery replacement . a diffusing / reflecting cap ( 21 ) covers the led ( 10 ) and pcb ( 9 ). fig5 shows the ornament of fig4 in cross section . tabs ( 23 ) on the battery holder ( 6 ) are permanently mated with slots ( 24 ) on the cap ( 4 ). the cap ( 4 ) is attached to the globe ( 2 ) using matching threads or other means ( not shown ). when the cap ( 4 ) is removed , the entire electronics assembly ( 11 ) is removed at the same time reducing the number of parts that must be handled while replacing the battery ( 8 ) or batteries . a light sensor ( 22 ) is placed on the same pcb as the light source ( 10 ) in relatively close proximity . a diffusing / reflecting cap ( 21 ) with extended annular ring ( 34 ) encloses the light source ( 10 ). the ornament design as shown if fig5 has a pressure relief opening ( 25 ). if opening 25 were not present , the air volume contained within the ornament ( 1 ) would be relatively sealed when the cap ( 4 ) was screwed down firmly against the neck ( 3 ). if there is a fairly rapid temperature drop , as might happen during a rain storm with falling temperatures , a vacuum will be built up inside the ornament ( 1 ). the formula that governs this is the perfect gas law , which is pv = nrt , where p is pressure , v is volume , n is the number of moles , r is the gas constant and t is temperature in degrees kelvin . in the case of a sealed globe v , n , and r are constants , and what remains is a linear relationship between pressure and temperature . therefore a globe at 46 f when cooled to 32 f , which is a reasonable scenario , undergoes a temperature change from 281k to 273k , or a drop of about 3 %. a corresponding drop in pressure of 3 %, if we start at sea level with a pressure of 14 . 7 lbs / sq ft , results in a 3 % drop in pressure , or about 0 . 4 psi . viewed instead as head of pressure , a 3 % change in pressure starting with atmospheric pressure at 33 . 9 ft , results in about 1 . 0 head - ft of pressure . or in layman &# 39 ; s terms this means the vacuum generated inside the globe is sufficient to suck the water to the top of a 12 ″ straw . therefore , if there is any possible leakage path in the globe , there is a strong propensity of the globe to suck in air , and also if the globe is wet or being rained upon to suck in water at the interface between neck ( 3 ) and cap ( 4 ). the opening ( 25 ) relieves the pressure difference and so prevents the ornament from sucking in water , the opening 25 also provides a drain hole if water does somehow get inside the ornament ( 1 ). fig6 shows the ornament of fig4 in cross section with the addition of rays to illustrate the more even illumination achieved by the present invention . ray ( 26 ) leaves the light source ( 10 ) and strikes the wall of the diffusing / reflecting cap ( 21 ). a portion of it , ray ( 27 ), is directed downward where it strikes the annular ring ( 34 ) and is reflected upwards as indicated by ray ( 28 ). a portion of ray ( 27 ) also passes through annular ring ( 34 ) ( not shown ). ray ( 28 ) strikes the globe ( 2 ) and is further scattered into rays ( 29 ) in a manner determined by the haze properties of the globe ( 2 ). the result is that the shadowed surface ( 18 ) of fig3 becomes illuminated . rays ( 30 ) through ( 33 ) illustrate another potential path to illuminate the shadowed surface ( 18 ) of fig3 . ray ( 30 ) leaves the light source and strikes the lower surface of diffusing / reflecting cap ( 21 ). a portion of it , ray ( 31 ), is reflected upwards . a portion of ray ( 30 ) also passes through the bottom surface of diffusing / reflecting cap ( 21 ) ( not shown ). ray ( 31 ) then strikes the wall of the diffusing / reflecting cap ( 21 ) and a portion of it passes through as indicated by ray ( 32 ). ray ( 32 ) strikes the globe ( 2 ) and is further scattered into rays ( 33 ) in a manner determined by the haze properties of the globe ( 2 ). it will be understood that there will be a multitude of rays scattered by the diffusing / reflecting cap ( 21 ) in multiple directions resulting in a relatively even illumination of the entire globe surface . fig7 shows an alternate construction of the diffuser / reflector cap ( 35 ) which does not include an annular ring but instead relies primarily on reflections from inner surfaces , as illustrated by ray ( 31 ), and upon the haze of the diffuser / reflector cap ( 35 ) to direct rays to the shadowed surface ( 18 ) of fig3 . fig8 shows a graph of light intensity ( 36 ) versus time for a light source that has brief periods ( 37 ) when it is periodically tuned off in order to allow a light sensing device that is in close proximity to measure the ambient light level without interference from the light source . if these brief periods are separated by less than about 30 ms , they will not be perceived by the human eye and the light source will appear as a constant glow with a perceived intensity that is set by the ratio of the amount of time the light is on to the amount of time the light is off . however , if the distance between the brief periods when the light is off is less than 30 ms , then the time that the light is off ( 37 ) must be significantly less than 30 ms or there will be a significant reduction in the perceived intensity of the light . this period of time may be too short to accurately measure the ambient light level , especially in battery operated products where it is desirable to operate the light sensing device a very low currents . if the brief periods ( 37 ) when the light is off are more than 30 ms apart , the light intensity will visibly flicker . fig9 shows the light intensity of a typical prior art ornament that blinks the light on and off in order to achieve acceptable battery life . the light source is on ( 38 ) for a relatively long time , usually 1 or 2 seconds . then the light source is off ( 39 ), during which time an ambient light sensor can measure the ambient light levels without interference from the light source . current consumption is decreased by the ratio of the on time ( 38 ) to the sum of the on time ( 38 ) and off time ( 39 ). the on time ( 38 ) can be chosen to be long enough to provide an interesting amount of illumination . the off time ( 39 ) can be chosen to provide a desired battery life for batteries of a given capacity . while effective for achieving a desired battery life , the decorative visual affect when using this approach suffers since the light source is off a large portion of the time . fig1 shows a method per the present invention that provides a more pleasing visual display while maintaining extended battery life . it is known that dark adapted eyes can easily see a surface that under daylight conditions would not appear to be illuminated . u . s . pat . no . 6 , 992 , 591 describes a method for energizing an led at very low current levels to illuminate a surface that is visible to dark adapted eyes and is incorporated here . instead of turning the led light source ( 10 ) completely off to conserve battery power , the light source is reduced to a level ( 42 ) as described in the 591 patent . as it is anticipated that the ornament ( 1 ) will only be illuminated at night when viewers will have dark adjusted vision , the surface of the ornament ( 1 ) will always appear to be illuminated providing a much improved visual experience when compared to prior art ornaments that turn completely off . to further enhance the visual effect , the on time ( 38 ) of fig9 is reshaped to provide a more pleasing effect . the light source intensity first increases rapidly ( 40 ) which draws immediate attention from the viewer . the rise time of section ( 40 ) can be selected to avoid an overly harsh transition which may not be pleasing . the light source intensity can then remain high for a period of time ( 41 ) which may be between 0 and several hundred milliseconds . section ( 41 ) is then followed by a gradually decreasing section back to the level of ( 42 ) for night adjusted eyes . the time constant of section ( 46 ) is selected to provide a pleasing visual experience . the area under the curves of fig9 and fig1 determine the amount of battery capacity that is used by each waveform . matching the area under the curves of sections 40 , 41 , 46 , and 42 to the area under the curve of section 38 results in identical battery life but with a much improved visual experience . fig1 shows a preferred embodiment of the intensity pattern for the present invention . a brief section ( 43 ) of zero intensity is inserted in order to allow a light sensing device ( 22 ) to measure the ambient light levels without interference from the internal light source ( 10 ). in order to prevent section ( 43 ) from causing a noticeable flick in the light intensity , it is immediately followed by a sudden increase in light intensity , section ( 40 ). while the eye can easily detect a blink as shown in fig8 , it cannot distinguish between two blinks in quick succession so the blink caused by section ( 43 ) will not be noticed as long as the rise time of section ( 40 ) is fast enough . a pulse of increased intensity is defined by section ( 40 ), ( 41 ), and ( 46 ) where section ( 41 ) may have zero length . the rise time of section ( 40 ) is chosen to be fast enough that a brief period of zero intensity immediately prior to section ( 40 ), section ( 43 ), is not noticeable to the human eye . in a preferred embodiment , section ( 43 ) is less than 100 ms in length and the rise time of section ( 40 ) is less than 250 ms . section ( 43 ) may be eliminated in designs that do not require the light source ( 10 ) to be turned off to measure ambient lighting conditions . in the preferred embodiment , section ( 46 ) has a fall time that is at least five times greater than the rise time of section ( 40 ). for the remainder of the time not defined by sections ( 43 ), ( 40 ), ( 41 ), and ( 46 ), the intensity is set to a non - zero level ( 42 ) that is visible to night adapted eyes . the intensity of section ( 42 ) is less than one third the intensity of section ( 41 ). the length of section ( 42 ) is at least twice the combined length of sections ( 43 ), ( 40 ), ( 41 ), and ( 46 ). those skilled in the art will recognize that the intensity patterns described by fig8 thru 11 may be generated in a multitude of ways including , but not limited to ; an application specific integrated circuit ( asic ), an embedded microprocessor , or discrete circuits using logic gates , counters / timers , etc . while this invention has been described as having an exemplary design , the present invention may be further modified within the spirit and scope of this disclosure . this application is therefore intended to cover any variations , uses , or adaptations of the invention using its general principles .