Abstract:
There is described an excimer radiation lamp assembly. The lamp assembly comprise a radiation emitting region and at least one substantially radiation opaque region. The radiation emitting region comprises a pair of dielectric elements disposed in a substantially coaxial arrangement.

Description:
FIELD OF THE INVENTION 
       [0001]    In one of its aspects, the present invention relates to an excimer radiation lamp assembly. In another of its aspects, the present invention relates to a radiation source module comprising the excimer radiation lamp assembly. In another of its aspects, the present invention relates to a fluid treatment system comprising the excimer radiation lamp assembly. 
       DESCRIPTION OF THE PRIOR ART 
       [0002]    Fluid treatment systems are known generally in the art. 
         [0003]    For example, U.S. Pat. Nos. 4,482,809, 4,872,980, 5,006,244, 5,418,370, 5,539,210 and Re:36,896 (all in the name of Maarschalkerweerd and all assigned to the assignee of the present invention) all describe gravity fed fluid treatment systems which employ ultraviolet (UV) radiation. 
         [0004]    Generally, such prior fluid treatment systems employ an ultraviolet radiation lamp to emit radiation of a particular wavelength or range of wavelengths (usually between 185 and 400 nm) to effect bacterial kill or other treatment of the fluid being treated. Many conventional ultraviolet radiation lamps are known as “low pressure” mercury lamps. 
         [0005]    In recent years, the art in low pressure mercury lamps has evolved with the development of the so-called Low Pressure, High Output (LPHO) and amalgam UV radiation lamps. These lamps have found widespread use in UV radiation water treatment systems, particularly those used for treatment of municipal drinking water and wastewater. As used herein, the term “low pressure” UV radiation lamp is intended to encompass conventional UV radiation lamps, LPHO UV radiation lamps and amalgam UV radiation lamps. 
         [0006]    Low pressure UV radiation lamps and medium pressure UV radiation lamps are the current standard used for UV radiation treatment of municipal drinking water and wastewater. 
         [0007]    In recent years, there has been development in the area of so-called excimer radiation lamps. These lamps have the potential to be used in a variety of applications. One such application is UV radiation treatment of water—e.g., municipal drinking water and wastewater. 
         [0008]    To date, there has been little or no development of excimer radiation lamps for use in the UV radiation treatment of water—e.g., municipal drinking water and wastewater. 
         [0009]    Accordingly, there is a real need in the art for an excimer radiation lamp that is well suited for use in the UV radiation treatment of water—e.g., municipal drinking water and wastewater. In a similar vein, there is a need in the art for a radiation source module and a fluid treatment system incorporating such an excimer radiation lamp. 
       SUMMARY OF THE INVENTION 
       [0010]    It is an object of the present invention to provide a novel radiation excimer radiation lamp assembly. 
         [0011]    It is a further object of the invention to provide a novel radiation source module. 
         [0012]    It is yet a further object of the present invention to provide a novel fluid treatment system. 
         [0013]    Accordingly, in one of its aspects, the present invention provides an excimer radiation lamp assembly comprising a radiation emitting region and at least one substantially radiation opaque region, the radiation emitting region comprising a pair of dielectric elements disposed in a substantially coaxialy arrangement. 
         [0014]    In another of its aspects, the present invention provides an excimer radiation lamp assembly comprising a radiation emitting region and an electrode in electrical connection with the radiation emitting region, at least a portion of the radiation emitting region comprising a substantially radiation opaque element independent of the electrode. 
         [0015]    In yet another of its aspects, the present invention provides an excimer radiation lamp assembly comprising an elongate cylindrical radiation emitting region and a substantially radiation opaque region, the elongate cylindrical radiation emitting region and the substantially radiation opaque region comprising substantially the same outer diameter. 
         [0016]    In yet another of its aspects, the present invention provides a liquid immersible elongate excimer radiation lamp assembly having a longitudinal dimension, the assembly comprising: 
         [0017]    a first end and a second end opposed to the first end; 
         [0018]    a first region interposed between the first end and the second end for emission of a radiation having a prescribed wavelength; and 
         [0019]    a second region juxtaposed with respect to the first region, the second region being radiation opaque or for emission of radiation different than the prescribed wavelength; 
         [0020]    wherein the first end has at least one cross-sectional dimension different than the second end. 
         [0021]    In yet another of its aspects, the present invention relates to an excimer radiation lamp assembly comprising a radiation emitting region and at least one substantially radiation opaque region, the radiation emitting region comprising a dielectric element and an electrode disposed in a substantially coaxial arrangement. 
         [0022]    In yet another of its aspects, the present invention relates to a radiation source module comprising the present excimer radiation lamp assembly. 
         [0023]    In yet another of its aspects, the present invention relates to a fluid treatment system comprising the present excimer radiation lamp assembly. 
         [0024]    In a highly preferred embodiment the present excimer radiation lamp assembly is configured so as to emit ultraviolet radiation. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0025]    Embodiments of the present invention will be described with reference to the accompanying drawings, wherein like reference numerals denote like parts, and in which: 
           [0026]      FIGS. 1-7  illustrate various views of a first embodiment of the present excimer radiation lamp assembly; 
           [0027]      FIGS. 8-12  and  16 - 18  illustrate various views of a second preferred embodiment of the present excimer radiation lamp assembly; 
           [0028]      FIGS. 13-15  illustrate various views of a third preferred embodiment of the present excimer radiation lamp assembly; 
           [0029]      FIGS. 19-23  illustrate a fourth embodiment of the present excimer radiation lamp assembly; 
           [0030]      FIGS. 24-27  illustrate a fifth embodiment of the present excimer radiation lamp assembly; 
           [0031]      FIGS. 28-30  illustrate a sixth embodiment of the present excimer radiation lamp assembly; and 
           [0032]      FIGS. 31-36  illustrate implementation of embodiments of the present excimer radiation lamp assembly in a radiation source module. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0033]    With reference to  FIGS. 1-7 , there is illustrated an excimer radiation lamp assembly  100  comprising a radiation emitting region  105 , a first radiation opaque region  110  and second radiation opaque region  115 . 
         [0034]    First radiation opaque region  110  may be suitably sized to serve as a parking spot for a cleaning system (not shown) used to remove undesirable materials from the surface of radiation emitting region  105 . 
         [0035]    Radiation opacity may be conferred to region  110  by any suitable means. For example, it is possible to apply a coating to the appropriate region of lamp assembly  100  which serves to confer radiation opacity to that region. 
         [0036]    Alternatively, it is possible to use a radiation opaque element secured to the appropriate region of lamp assembly  100 . Non-limiting examples of such radiation opaque elements may be selected from the group consisting of ceramic, rubber, plastic, wood and mixtures thereof. 
         [0037]    The provision of region  110  provides a suitable parking location for a cleaning system whereby the seals and other components of the cleaning system will be less likely to damage and/or failure from exposure to radiation. 
         [0038]    Radiation opaque region  115  comprises an end portion  120  having a relatively large diameter and a radiation opaque element  125 . Preferred embodiments of region  115  are shown in  FIGS. 1-3 . 
         [0039]      FIG. 1  illustrates an enlarged perspective view of end region  115  comprises an opening  130  receiving an electrode (not shown) conventionally used in excimer radiation lamp assemblies. 
         [0040]      FIG. 2  is a view of  FIG. 1  at the opposite end thereof. 
         [0041]      FIG. 3  is a modification of the embodiment shown in  FIG. 1  whereby a dome or a cover element  135  is placed between radiation emitting region  105  and end portion  120 . 
         [0042]    The important point is that end region  115  contains a radiation opaque region which serves to protect the seals and other components of the radiation lamp assembly and/or its surrounding environment. 
         [0043]      FIG. 4  illustrates implementation of the embodiment illustrated in  FIG. 3  whereas  FIG. 5  illustrates implementation of the embodiments illustrated in  FIGS. 1 and 2 .  FIGS. 4 and 5  show a ghosted outline of the internal design of an otherwise conventional excimer radiation lamp assembly. 
         [0044]    The provision of regions  110  and  115  serve to protect components and other accessories used with the lamp in a fluid treatment system from damage owing to radiation exposure. Further, by providing a larger diameter structure in region  115 , radiation lamp assembly  100  is effectively “keyed” so that it can be installed in a unidirectional manner. 
         [0045]    With reference to  FIGS. 8-12  and  16 - 18 , there is shown an excimer radiation lamp assembly  200 . 
         [0046]    In the subsequent figures of the present application, the last two digits in a reference numeral are intended to denote a similar element as that shown in the embodiment for  FIGS. 1-7 . Thus, radiation opaque region  115  in  FIGS. 1-7  is similar to radiation opaque element  215  in the embodiment shown in  FIGS. 8-12  and  16 - 18 , etc. 
         [0047]    The embodiment shown in  FIGS. 8-12  and  16 - 18  is similar to that shown in  FIGS. 1-7  with the exception that a larger diameter element is not provided in region  215  of excimer radiation lamp assembly  200 . 
         [0048]    With reference to  FIGS. 10-12 , additional detail is given on the design of radiation lamp assembly  200 . Thus, as is conventional in art of excimer radiation lamps, an annular chamber  240  is provided. A phosphor material (not shown) may be applied to one or both, preferably both of surfaces  245  and  250  of annular chamber  240 . 
         [0049]    With regard to radiation opaque region  210 , radiation opacity may be conferred to this region as discussed above by applying suitable radiation opaque material to the outer and/or inner surfaces of annular chamber  240  corresponding to radiation opaque region  210 . 
         [0050]    The embodiment shown in  FIG. 12  extends annular chamber  240  partially to the end of radiation lamp assembly  200 . 
         [0051]    With reference to  FIGS. 16 and 17 , these Figures show a side elevation with ghosted lines of the embodiment illustrated in  FIGS. 8 and 9 . 
         [0052]      FIG. 17  illustrates a cross-section of the embodiment shown in  FIG. 16 . 
         [0053]    The embodiment shown in  FIG. 18  is a slight modification of that shown in the earlier figures. Specifically, in the embodiment shown in  FIG. 18 , radiation opaque region  210  is of the same size as radiation opaque region  215 . This embodiment is particularly well suited to the situation where a cleaning system (not shown) can suitably clean the exterior of radiation emitting region  205  in a single stroke. 
         [0054]    With reference to  FIGS. 13-15 , there is illustrated excimer radiation lamp assembly  300 . 
         [0055]    The principal modification in excimer radiation lamp  300  is the provision of a cone-shaped element  355  at the distal end of radiation opaque region  310 . The provision of cone-shaped portion  355  facilitates self-location of radiation lamp assembly  300  during insertion thereof in a fluid treatment system. 
         [0056]    Cone-shaped portion  355  may be made of quartz or any other suitable material that is durable in the environment in which radiation lamp assembly  300  is used. 
         [0057]    With reference to  FIGS. 19-23 , there is illustrated a radiation lamp assembly  400 . 
         [0058]    The principal modification in excimer radiation lamp  400  is the provision of a square shaped portion  455  at the distal end of radiation opaque region  410 . The provision of square-shaped portion  455  facilitates self-location of radiation lamp assembly  400  during insertion thereof in a fluid treatment system. 
         [0059]    With reference to  FIGS. 24-27 , there is illustrated a excimer radiation lamp assembly  500 . Excimer radiation lamp assembly  500  is similar to excimer radiation lamp  400  illustrated in  FIGS. 19-23 . The principal difference is annular element  517  has been added to lamp assembly  500 , effectively to provide a double-keying capability to the lamp assembly. This ensures that the lamp be installed in a single manner only. 
         [0060]    With reference to  FIGS. 28 and 30 , there is illustrated an excimer radiation lamp assembly  600 . 
         [0061]    The principal modification from the prior embodiments to excimer radiation lamp assembly  600  is the provision of a step-down portion  618  which serves to provide a “keying” function as described above. In other words, rather than having an enlarged diameter at this portion of the radiation lamp assembly, a step-down portion is provided to achieve a similar goal. 
         [0062]    With reference to  FIG. 29 , there is illustrated a excimer radiation lamp assembly  700 . 
         [0063]    As show, excimer radiation lamp assembly  700  includes a chamfered portion  719  at the end of each of radiation opaque regions  710  and  715 . The provision of chamfered portion  719  facilitates combination of excimer radiation lamp assembly  700  to provide a substantially fluid tight seal when radiation lamp assembly  700  is used in a fluid treatment system. 
         [0064]    With reference to  FIGS. 31-36 , there is illustrated various embodiments of radiation source modules incorporating any of excimer radiation lamp assemblies 100,200,300,400,500,600,700. 
         [0065]    Thus, there is shown a radiation source module  10  which is generally similar in design to the module shown in the U.S. Pat. No. 5,418,370—i.e., the radiation source is generally cantilevered with respect to a single support element  15 . 
         [0066]    When implementing a excimer radiation lamp assembly in a fluid treatment radiation source module such as module  10 , a center electrode  20  is affixed to support element  15 . Thereafter, the excimer radiation source assembly (excimer radiation source assembly  100  is shown as an example) is disposed over center electrode  20  and affixed thereto via a coupling nut  25  and a cap element  30 . While  FIGS. 31-36  do not show the detail of O-rings and other sealing elements, the selection and use of O-rings and other sealing elements is within the purview of a person of skill in the art. 
         [0067]    All publications, patents and patent applications referred to herein are incorporated by reference in their entirety to the same extent as if each individual publication, patent or patent application was specifically and individually indicated to be incorporated by reference in its entirety. For greater certainty, two copending U.S. provisional patent applications 60/752,026 (Gowlings Ref: T8469434US) 60/752,025 (T8469435US), both filed on Dec. 21, 2005 in the names of the present inventors, are each incorporated herein by reference.