Patent ID: 6454465
Filing Date: 2002-09-24
Classification: G02B

Abstract:
A method of making an optical filtering device having a ferrule, an input fiber pigtail disposed axially within the ferrule, an output fiber pigtail having a core, an optical filter having a surface and a characteristic optical transmission property dependent upon the angle of incidence upon the optical filter, a collimating lens having an output end, a filter-holder unit defining a lens cavity, and an insulated tube having a first end and a second end, the method comprising the steps of:optically aligning the collimating lens proximate to and in series with the output end of the ferrule, the ferrule being disposed within the first end of the insulated tube, the collimating lens being at least partially disposed within the second end of the insulated tube; radially centering the output end of the collimating lens within the lens cavity of the filter-holder unit; transmitting a test light beam through the input fiber pigtail; adjusting the position of the filter-holder unit to achieve a desired angle of incidence of the test light beam upon the surface of the optical filter, the desired angle of incidence being determined by the characteristic optical transmission property of the optical filter; determining an angle of reflection of the test light beam reflected by the optical filter based upon the desired angle of incidence; disposing the output fiber pigtail within the ferrule such that the output fiber pigtail is spaced a distance apart from the input fiber pigtail, and such that the test light beam reflected by the optical filter at the angle of reflection towards the output fiber pigtail is incident upon the core of the output fiber pigtail; and securing the output fiber pigtail and the filter-holder unit in position to maintain the desired angle of incidence and the angle of reflection for the optical filtering device.