fig1 and 2 shows a fiber - grating stabilized pump laser component , which has been constructed according to the principles of the present invention . specifically , an optical source 110 , such as a laser , specifically , pump laser or amplifier , is installed on a submount 112 in the typical implementation . the submount 112 provides mechanical and electrical connections between the laser diode 110 and the module housing 114 . a fiber pigtail 118 extends through a side wall 120 of the module housing 114 . it is typically rigidly secured to the submount 112 such that the fiber endface 122 is held in proximity to an output facet 116 of the laser diode 110 . the fiber pigtail 118 is constructed from polarization - maintaining fiber . different types of polarization - maintaining fiber are applicable . for example , panda , elliptical stress bar , elliptical core , and bow tie may be used . fig3 a through 3c are cross - sectional views illustrating a few exemplary types of pm fiber deployable with the present invention , specifically panda , elliptical stress bar , and bow tie , respectively . each of these pm fiber types is doped to yield a fast and slow axis of light transmission . light that is coupled into the fiber and polarized along one of these axes is restricted to maintain its polarization with respect to the axes . in other embodiments , the fiber pigtail 118 is constructed from a type of polarization - maintaining fiber that is termed polarization - controlling fiber . this fiber type only propagates light with a single polarization . returning to fig1 and 2 , the present invention contemplates the various techniques used for ensuring a high collection efficiency for light exiting from the light output facet 116 of the laser diode into the fiber pigtail 118 . specifically , discrete lenses , butt coupling , and microlenses are various alternatives . presently , flat top microlenses are used as described in the application entitled “ flat top , double - angled , wedge - shaped fiber endface ”, u . s . ser . no . 08 / 965 , 798 , by jeffrey korn , steven d . conover , wayne f . sharfin and thomas c . yang , which is incorporated herein by this reference . the advantage of double - angle flat top microlenses is the fact that they are not circularly symmetric , i . e ., with respect to the fiber &# 39 ; s axis , to thereby match the elliptical spatial distribution of light from the output facet of the laser diode . however , cylindrical fiber lenses , a cylindrical discrete lenses can also be used . when non - circularly symmetric coupling techniques are used , it is important to align the formed microlense , for example , with one of either the fast or slow axes of the polarization - maintaining fiber . fig4 illustrates the relationship between the double - angle flat top microlense and the pm fiber &# 39 ; s transmission axes . specifically , breaklines bl 1 , between polished surface s 1 and cleaved flat top surface s 3 , and breakline bl 2 , between top surface s 3 and polished surface s 2 , are substantially aligned with one of the pm fiber &# 39 ; s axes . here , the breaklines bl 1 and bl 2 are aligned with the slow axis . it is equally valid to align the breaklines bl 1 and bl 2 with the fast axis , in alterative embodiments . in the present invention , the accuracy of the alignment is between zero and five degrees relative to either the fast or slow axis . that is , there is less than 5 degrees of angular difference between the breaklines bl 1 , bl 2 and the selected fiber transmission axis . preferably , however , the alignment is between 0 and 2 °. this level of alignment ensures that little light is coupled to travel along the nonfavored axis of transmission , and thus maximizing the polarization - controlling effect of the fiber pigtail 118 . the polarization control maximizes and stabilizes the effect of the fiber grating . light exiting from the typical diode laser is polarized . as a result , any light that is coupled into the other , non - favored fiber axis , i . e ., the axis of the fiber that is not aligned with the polarization of the laser diode , is reflected by the grating , but has little effect on the laser diode since the diode is nonresponsive to light of this polarization . returning to fig1 and 2 , the polarization - maintaining fiber pigtail 118 is optically coupled to a strand of regular fiber 124 via splice 126 . regular fiber preferably has a standard circular cross section core , i . e ., has no stress bar , or no fast or slow axes , as illustrated in fig3 d . although the coupling between the polarization - maintaining fiber pigtail 118 and regular , non - polarization - maintaining fiber 24 is shown as a direct fusion splice . the critical feature is the optical coupling between the two fibers . thus , other techniques for obtaining this coupling can be used such as intervening fiber lengths of a third fiber . in a similar vein , the pm fiber need not directly receive the light from the diode . instead , the light can be first coupled into a relatively short length of regular fiber for example , and then into pm fiber , which transmits the light over most of the distance to the grating . this is not preferred , however , because of the need for additional splicing . a grating 128 is written into the regular fiber 124 . these gratings are typically manufactured by uv beam interference . the gratings are usually written to the depth of the core in the fiber . in one implementation , the fiber grating 128 provides reflectivity at about 980 nm , which is within the gain bandwidth of the diode laser 110 . further , the fiber grating has a bandwidth of 0 . 5 - 1 nm , preferably . preferably , the grating has a power reflectivity of about 1 . 3 % to 2 . 3 %, preferably 1 . 4 % to 2 . 0 %. the front facet power reflectivity of the laser chip is 4 . 0 % to 6 . 5 %, preferably 4 . 5 % to 6 . 0 %. these ranges are used with a laser - to - fiber coupling efficiency of 70 - 75 %. in other implementations , also involving erbium - doped fiber amplifiers , the grating 128 is reflective at 1480 nm . in implementations using raman amplification , the grating has a bandwidth of 0 . 5 - 20 nm any where in the range of 1060 - 1600 nm . important to the performance of the inventive systems is the distance ( 1 ) between the splice point 126 and the grating 128 . generally , this distance should be kept short to minimize the region without polarization control between the laser diode 110 and grating 128 . in the preferred embodiment , the distance ( 1 ) is 50 - 150 mm , but can be a wider range such as 0 mm to 500 mm . in the preferred embodiment , the regular fiber 128 transmits the signal from the optical device 110 to the next device or system 130 . in the preferred implementation , this system is a fiber amplifier system with the light being used to pump the fiber amplifier 130 . for example , the diode pump component 100 can be attached to the fiber amplifier through a wdm coupler to provide the pump light into the fiber amplifier &# 39 ; s core . regular fiber , however , is typically used in raman systems . one of the primary advantages of the present invention surrounds the fact that the commercial , fiber - grating stabilized optical component 100 , which is shipped to customers , contains the pm fiber to non - pm fiber splice 126 . in the past , it has been common to use lengths of pm fiber for polarization control in various systems . typically , these systems have been used in laboratory environments . pm fiber , however , was difficult to deploy in commercial systems . many end - users do not want to splice regular fiber to pm fiber because of the difficulties associated with the fusion process , especially in the field . further , as noted previously , there was expenses associated with pm fiber with gratings , and some pm fiber is hard to write on . in contradistinction , with the present invention , the fiber - grating stabilized pump laser component , for example , is shipped to a user in the typical implementation , with a non - pm fiber splice end . therefore , there is no concern regarding splicing to pm fiber . moreover , problems associated with gratings in pm fiber are avoided . fig5 is a flow diagram illustrating the process for manufacturing the optical component 100 . first , the microlense 122 is formed on the end of a length of pm - maintaining fiber . in a preferred embodiment , a flat - top , endface microlense is formed . since this microlense is not circularly symmetric , when the microlense is polished , the pm fiber is initially installed in the polishing jig such that one of its polarization axes , either the fast axis or the slow axis , is aligned to the formed microlense , to yield an alignment as discussed in relation to fig4 . that is , the microlense is rotationally aligned with the polarization axes of the fiber . if polarization - controlling fiber is used , the lense is aligned to the only polarization axis . next , in step 212 , the pm fiber pigtail 118 is installed on the submount 112 . specifically , known alignment techniques are used such that the formed microlense is located relative to the laser diode 110 such that coupling efficiency of the light generated by the laser diode is maximized into the pm fiber pigtail 118 . specifically , the microlense is located near the exit facet of the laser and rotationally aligned such that the polarized light from the laser is launched to propagate along either the fast or slow axes of the pm fiber . the other end of the pm fiber pigtail 118 is prepared for splicing . specifically , the outer coating and jacket of fiber is removed in step 214 leaving the bare glass . in step 216 , the non - pm fiber is also prepared for splicing . specifically , approximately 150 mm or less of the non - pm fiber is preserved on the near , or laser , side of the grating 128 . the outer coating and jacket of fiber is then removed . next , the pm fiber pigtail 118 is fusion spliced to the non - pm fiber 124 using conventional pm - to - non - pm fiber splicing techniques in step 218 . mechanical or flame splicing could also be used , however . the quality of the completed splice is tested in step 220 . specifically , the laser diode is operated and the splice - related losses are characterized . if the loss is determined to be unacceptably high in step 222 , the splice is removed in step 224 and the pm fiber and non - pm fiber are re - spliced using the remaining 150 mm or less of non - pm fiber on the near proximal side of the grating . presently , splice losses of about 3 % are typical . if the splice is determined to have acceptable losses , however , an ultraviolet - curable polymer is coated over the region of the splice in step 226 . multiple coats of his protective polymer can be used to improve pull - strength . in step 228 , a protective sleeve is installed over the region of the splice . the component is then retested to confirm acceptable power characteristics , in step 230 . finally , in step 232 , screening methods and tests are employed to remove bad parts . while this invention has been particularly shown and described with references to preferred embodiments thereof , it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims .