fig1 shows intensities as a function of wavelength of a doped mercury uv lamp . as can be seen , there is light in the range from approximately 250 nm and up . a line is shown at 270 nm because a filter can be installed in order to remove light under that wavelength . fig2 shows a graph for sulphur lamps of different powers . the spectrum is very similar to daytime solar light at the earth &# 39 ; s surface . therefore , a sulphur lamp can be used to provide natural light . sulphur lamps are known in the art and will not be described in detail . as can be seen , there is little uv light . uv light is electromagnetic radiation with a wavelength of between 10 nm and 400 nm . a sulphur lamp can be doped with metals in order to achieve light emission as close to natural light as technically possible . a lamp assembly according to the present invention can be a combination of the doped uv lamp and a mercury lamp , as an alternative the sulphur lamp described above can be used . if the lamp assembly comprises these two lamps , it is possible to regulate the uv and the natural light independently . as an example , such a lamp assembly can be installed in an animal farm production building , then the mercury lamp can be used as illumination to represent the daytime and so that the farmer can work in the animal farm production facility , such as a building accommodating cows . the uv lamp can then be turned on and off for only a limited amount of time each day , for example 1 , 2 or 4 hours every day . by using the natural light lamp ( here exemplified as a mercury lamp ) as illumination in the building no other lighting installation is needed . hence , the costs of the normal illumination can be reduced . in another embodiment the lamp assembly comprises one doped mercury lamp . the lamp can be doped with , for example iron , tin , lead , phosphorus , sulphur , selenium , boron , silicon , germanium , arsenic , antimony and / or tellurium . such a lamp both emulates natural light and has enhanced intensities in the uv area . the light with wavelength under 270 nm can then removed by use of a filter . when using such a lamp there is used only one lamp needs to be installed as it can be used as normal illumination . in addition it will enhance the vitamin d production in living organisms exposed to its light . this means that a farmer only needs to install this type of lamps in his livestock accommodating production facilities in order to increase the vitamin d content of the produced milk . the following table includes examples of different lamp types that can be used in a lamp assembly . min . max . lamp type no . nm nm mercury florescent low pressure 1 270 315 mercury medium pressure doped 2 270 315 mercury medium pressure doped 3 270 900 mercury medium pressure 4 380 900 mercury high pressure 5 260 900 xenon high pressure 6 300 900 mercury high pressure doped 7 270 900 xenon high pressure doped 8 270 900 sulphur 9 380 900 plasma and / or incandescent lamp . ( solar simulator ) 10 380 900 doped plasma and / or doped incandescent lamp ; 11 270 900 ( solar simulator ) with use of examples of the lamps in the table different embodiments of a lamp assembly can be made . the following table has examples of lamp assemblies made from the lamp types from the above shown table . thus , the lamp assemblies a to j are a combination of two lamp types and the lamp assemblies k to o only use one lamp . as the lamp assembly is to be used as lighting , it is preferred that the lighting appears to be continuous . a pulsed lamp will not only stress the animals but also make it difficult for the farmer to work , most of the known uv and natural light lamps are to some extend pulsed but as long as the pulses are higher than 50 hz it will appear to both animals and humans to be continuous . the fig3 a , 3b and 4 show a lamp assembly according to an embodiment of the invention , where a medium and / or high pressure lamp 1 is accommodated in a lamp house 8 . the lamp 1 has a set of electrodes 2 at each end which are fitted to electrical power supplies 3 and mounted with electrical insulation sockets 4 in the lamp house 8 . the lamp house 8 has side reflectors 5 on each side of the lamp 1 , a reflector 6 curved behind the lamp 1 , and with an optical edge filter 7 in front of the lamp 1 . outside the reflector 6 on the lamp house 8 an electronic control box 9 is provided with cable connections 11 provided thereon . on the rear of the outside of the lamp house 8 a ventilator 10 is provided whereby the temperature of the lamp assembly may be controlled . in an embodiment , the lamp assembly has a lamp that can provide both natural light and uv light at the same time . such a lamp can be a mercury , sulphur , xenon lamp doped with metal , non - metals or metalloids , for example , any combination of tin ( sn ), lead ( pb ), iron ( fe ), phosphorus ( p ), sulphur ( s ), selenium ( se ), boron ( b ), silicon ( si ), germanium ( ge ), arsenic ( as ), antimony ( sb ) and / or tellurium ( te ). these elements can enhance the intensities in the 270 nm to 315 nm range . a test of an embodiment of the invention has been performed . here , the uv lamp having the spectrum as shown in fig1 was used together with a sulphur lamp to illuminate cows . the lamp assembly was installed 3 to 3 . 5 meters from the cows in the test . the lamp was turned on for 30 minutes every 24 hours . this was repeated for 28 days . the test was performed on four cows , having the numbers : 5895 , 6142 , 6238 and 2023 . the cows were milked every day and the vitamin d3 content of the milk was measured for each of the four cows . the result of the test is shown in fig5 . it can be seen that the content of d3 vitamin increases from about 3 ng / ml to about 25 ng / ml . this is a substantial increase in the d vitamin content of the milk . besides increasing the content of d3 vitamin in the produced milk in cattle farming , it is realised that the uv lamp arrangement according to the invention may also increase the d vitamin content in other animals . as shown in fig6 , a study of d vitamin status in pigs clearly shows an increase in the content of d vitamin when the pigs are exposed to the uv lamp arrangement according to the invention ( lots # 92 and # 94 ) compared to the animals given d3 vitamin in their food ( lots # 91 and # 93 ). fig7 shows the d3 vitamin content in the produced milk of cows — both conventional cattle and organic bread cattle — when exposed to natural sunlight during the winter and during the summer in comparison with an exposure to the lighting of the uv lamp arrangement according to the invention for a predetermined amount of time every day . as shown in fig7 , studies also reveal that it is sufficient to expose the animals , such as cows , for 30 minutes every day in order to achieve the desired result to reproduce the d3 vitamin content naturally occurring during summer when the animals are free - ranging outside and thereby exposed to sunlight . in particular these studies reveal that by the present invention it is possible to reproduce the same high amount of d3 vitamin content in milk as in the milk from organically farmed cows during summer but all around the year .
the invention regards an apparatus for promoting d - vitamin production in a living organism , comprising at least one lamp assembly , said at least one lamp assembly is adapted to emit polychromatic light , wherein the polychromatic light at least emulates natural light and uv light at wavelengths between 270 nm and 315 nm .