Ying Diqing
College of Optical Science and Engineering, Zhejiang University, Hangzhou 310027, China.
iScience. 2024 Aug 20;27(9):110769. doi: 10.1016/j.isci.2024.110769. eCollection 2024 Sep 20.
The side-firing instrument is studied under the complete bevel angle range. The fiber core and cladding are 0.6 mm and 0.66 mm, respectively, the fiber core refractive index is 1.457, and the fiber cladding refractive index is from 1.409 to 1.452 corresponding to the numerical aperture from 0.37 to 0.12. The bevel angle range is subdivided by ten crucial angles, whose relationship changes as the fiber cladding refractive index reaches 1.418. The beam's divergence angle and coverage increase as the bevel angle deviates from being equal and close to π/4 rad, respectively. When all rays achieve total internal reflection, with numerical aperture being 0.37, the divergence angle and coverage would increase by 28.29% and 44.74%, respectively. The required emission opening size has a minimum under the bevel angle being close to π/4 rad, whose expression is obtained. It increases sharply as the bevel angle reaches a certain value.
对侧面发射仪器在全斜角范围内进行了研究。光纤纤芯和包层分别为0.6毫米和0.66毫米，光纤纤芯折射率为1.457，光纤包层折射率在1.409至1.452之间，对应数值孔径从0.37至0.12。斜角范围由十个关键角度细分，随着光纤包层折射率达到1.418，它们的关系会发生变化。当斜角偏离等于并接近π/4弧度时，光束的发散角和覆盖范围分别增大。当所有光线都实现全内反射且数值孔径为0.37时，发散角和覆盖范围将分别增加28.29%和44.74%。在斜角接近π/4弧度时，所需的发射开口尺寸最小，并得到了其表达式。当斜角达到一定值时，它会急剧增大。
