the improvement provided by the present invention is to replace the teflon ™ introducer with a quartz cap that is secured to the end of the fiber by a metal crimp sleeve . an example is illustrated in fig1 , which shows a fiber having a silicon core 1 , conical tip 2 , teflon ™ buffer 3 , and cladding layer 9 . the conical tip 3 directs laser energy supplied by the fiber in a generally radial direction though a quartz cap 4 , which is secured to the teflon ™ buffer 3 by a metal crimp sleeve 5 that is crimped to the buffer at one end 6 , and that is secured to the quartz cap at a second end 7 by a layer of epoxy 8 . the generally radial laser output is indicated by reference numeral 10 . in order to prevent thermal runaway to the quartz cap , a preferred method of using the arrangement illustrated in fig1 is to modulate the laser output during treatment of a tissue , for example by moving the fiber back and forth . the quartz cap arrangement described herein may advantageously be used with safety feedback arrangements of the type disclosed in copending u . s . patent application ser . nos . 11 / 510 , 691 , filed aug . 28 , 2006 ( pub . no . 2007 / 0049911 , mar . 1 , 2007 ); 11 / 714 , 785 , filed mar . 7 , 2002 ( pub . no . 2007 / 0049911 , mar . 1 , 2007 ); and 12 / 047 , 819 , filed mar . 13 , 2008 ( pub . no . 2009 / 0062782 , mar . 5 , 2009 ) to ensure that damage is minimized or prevented should overheating occur despite the modulation . the copending applications are incorporated herein by reference . use with a safety feedback arrangement involves monitoring a temperature of the treatment site or radiation emitted during treatment in order to prevent damage due to overheating . as explained in the copending applications , different wavelengths of radiation may be monitored , including but not limited to visible light , and the monitoring may be carried out either by detectors at or near the treatment site or by transmitting the radiation back through the fiber . having thus described preferred embodiments of the invention in sufficient detail to enable those skilled in the art to make and use the invention , it will nevertheless be appreciated that variations and modifications of the illustrated embodiment may be made without departing from the spirit of the invention . for example , different fibers may be substituted for the illustrated silicon core / teflon ™ buffer fiber , so long as the quartz cap can be secured thereto by a crimp sleeve . in addition , the crimp sleeve need not necessarily be made of metal , and the adhesive used to secure the quartz cap need not necessarily be epoxy . for example , adhesive materials other than epoxy may be substituted for epoxy layer 8 , and the metal crimp sleeve may alternatively be secured to the quartz cap by mechanical means , by welding , or by any other metal - to - quartz joining method or material . still further , the crimp sleeve may be made of a material other than metal , transparent materials other than quartz may used in the cap , and the conical tip may be replaced by other tips such as the alternative tips disclosed in u . s . patent application ser . no . 11 / 510 , 691 , including orb - shaped , inverted cone - shaped , and angled tips , as well as tips with separate reflective structures such as the one shown in fig4 e of u . s . patent application ser . no . 11 / 510 , 691 . in addition , the arrangement of the preferred embodiments may be used with feedback arrangements other than those disclosed in u . s . patent application ser . nos . 11 / 510 , 691 ; 11 / 714 , 785 ; and 12 / 047 , 819 , cited above , or without feedback , and in a wide variety of applications , including but not limited to endovascular applications . it is therefore intended that the invention not be limited by the above description or accompanying drawings , but that it be defined solely in accordance with the appended claims .
an apparatus for delivering energy , and in particular laser energy , to a tissue includes a protective quartz cap that is secured to a laser delivery fiber by a crimp sleeve . the fiber may have a conical tip , and the quartz cap may be secured to the crimp sleeve by a layer of epoxy .