Patent Number: 
Section: claims

1. A fluid element device comprising: a plurality of fluid elements arranged in a matrix configuration having rows and columns, the level of fluid in each of said fluid elements being controllable by means of an electric force, said fluid elements comprising capillary tubes, each of said capillary tubes comprising a plurality of electrode segments electrically insulated from one another such that each of said segments is receivable of a different electric voltage;  first means for applying an electric force to a number of selected fluid elements in one or more of said rows of fluid elements; and  second means for applying an electric force to a number of selected fluid elements in one or more of said columns of fluid elements such that the fluid level rises in the selected fluid elements to which an electric force is applied by both said first means and said second means. 2. The device according to  claim 1 , wherein said electrode segments of each of said capillary tubes are arranged inside said capillary tubes. claim 1 3. The device according to  claim 1 , wherein said electrode segments each comprise a coating layer of an electrically conducting material. claim 1 4. The device according to  claim 1 , wherein said electrode segments of at least one of said capillary tubes extend in a longitudinal direction of said capillary tube. claim 1 5. The device according to  claim 1 , wherein said electrode segments of at least one of said capillary tubes extend in a transverse direction of said capillary tube. claim 1 6. The device according to  claim 1 , wherein at least one of said electrode segments is coupled to said first means. claim 1 7. The device according to  claim 1 , wherein at least one of said electrode segments is coupled to said second means. claim 1 8. The device according to  claim 1 , further comprising third means for applying an electric force to at least one of said electrode segments such that when the level of fluid in said capillary tube reaches said electrode segment, application of a voltage of a predetermined value to said electrode segment by said third means will maintain the level of fluid in said capillary tube independent of the application of an electric force by said first and second means to thereby provide said capillary tube with a memory effect with said electrode segment constituting a memory electrode. claim 1 9. An X-ray filter comprising a device according to  claim 1 , wherein said capillary tubes are at least partially filled with an X-ray absorbing fluid. claim 1 10. The device according to  claim 1 , wherein said plurality of electrode segments in at least one of said capillary tubes comprises sequentially arranged first, second and third electrode segments. claim 1 11. The device according to  claim 10 , wherein said first electrode segment is coupled to said first means and said second electrode segment is coupled to said second means, said first and second means being controllable such that upon application of voltages of predetermined values to both said first and second electrode segments by said first and second means, the fluid in said capillary tube will rise above said first and second electrode segments. claim 10 12. The device according to  claim 11 , further comprising third means for applying an electric force to said third electrode segment such that when the level of fluid in said capillary tube reaches said third electrode segment, application of a voltage of a predetermined value to said third electrode segment will maintain the level of fluid in said capillary tube independent of an electric force applied by said first and second means to thereby provide said capillary tube with a memory effect with said third electrode segment constituting a memory electrode. claim 11 13. The device according to  claim 10 , wherein said second electrode segment is coupled to said first or second means, whereby upon application of a voltage to the fluid in said capillary tube above a threshold relative to the voltage applied to said second electrode segment, the fluid will rise above a gap between said first and second electrode segments. claim 10 14. The device according to  claim 13 , further comprising third means for applying an electric force to said third electrode segment such that when the level of fluid in said capillary tube reaches said third electrode segment, application of a voltage of a predetermined value to said third electrode segment will maintain the level of fluid in said capillary tube independent of the application of an electric force by said first and second means to thereby provide said capillary tube with a memory effect with said third electrode segment constituting a memory electrode. claim 13 15. The device according to  claim 1 , wherein said electrode segments are spaced from one another to define a gap between each adjacent pair of electrode segments. claim 1 16. The device according to  claim 1 , wherein said plurality of electrode segments comprises at least first and second electrode segments, said first electrode segment being coupled to said first means and said second electrode segment being coupled to said second means. claim 1 17. An X-ray examination device comprising: an X-ray source;  an X-ray detector spaced from said X-ray source; and  an X-ray filter arranged between said X-ray source and said X-ray detector, said X-ray filter comprising  a reservoir for storing X-ray absorbing fluid;  a plurality of fluid elements arranged in a matrix configuration having rows and columns, said fluid elements being in fluid communication with said reservoir, the level of fluid in each of said fluid elements being controllable by means of an electric force, said fluid elements comprising capillary tubes, each of said capillary tubes comprising a plurality of electrode segments electrically insulated from one another such that each of said segments is receivable of a different electric voltage;  first means for applying an electric force to a number of selected fluid elements in one or more of said rows of fluid elements; and  second means for applying an electric force to a number of selected fluid elements in one or more of said columns of fluid elements such that the fluid level rises in the selected fluid elements to which an electric force is applied by both said first means and said second means. 18. A fluid element device, comprising: a plurality of fluid elements arranged in a matrix configuration having rows and columns, the level of fluid in each of said fluid elements being controllable by means of an electric force;  first means for applying an electric force to a number of selected fluid elements in one or more of said rows of fluid elements;  second means for applying an electric force to a number of selected fluid elements in one or more of said columns of fluid elements such that the fluid level rises in the selected fluid elements to which an electric force is applied by both said first means and said second means; and  fluid level retention means for maintaining the level of fluid in the selected elements, after the fluid has risen by the application of an electric force applied by both said first means and said second means, at the elevated level independent of the application of an electric force by said first means and said second means. 19. The device according to  claim 18 , wherein said fluid elements comprise capillary tubes, each of said capillary tubes comprising a plurality of electrode segments electrically insulated from one another such that each of said segments is receivable of a different electric voltage. claim 18 20. The device according to  claim 19 , wherein said fluid level retention means comprise one of said electrode segments and third means for applying an electric force to said one of said electrode segments. claim 19