Design of compact fiber microscope objective

The construction, operation and maintenance of optical fiber communication network put forward the portable, compact, accurate and reliable requirements for the use of optical fiber connecting machine. To achieve this goal, an optical fiber objective with compact structure and clear imaging was developed. Based on optical theory and actual usage requirements, the basic optical parameters of the required objective were analyzed. An compact and high- resolution optical fiber microscope objective was designed by the Zemax software. The objective included 5 commonly used glass spherical lenses, with the magnification of 6 times, the numerical aperture of 0.24, and the conjugate distance of 47.3 mm. The objective system had the good imaging quality, in which the MTF was greater than 0.36 at the nyquist frequency of 60 lp/mm, greater than 0.15 at 90 lp/mm within 0.7 field of view. The design results were analyzed by Monte Carlo tolerance, and the yield rate was over 90%. The installation was loose and the cost was low, therefore the objective lens could be produced in large quantities. In addition, the imaging simulation of the designed objective lens shows that the features of the fiber core to be spliced are clear and sharp, which is beneficial to the alignment of the machines.