基于Hankel波理论分析了非相干光源产生Bessel光束的自重建特性,利用光学设计软件ZEMAX模拟了Bessel光束经过轴上圆形障碍物后的截面光强分布.由于发光二级管(LED)具有一定的频谱宽度且不像激光具有很高的相干度,因此我们采用一定频宽范围的连续谱来描述.从模拟结果可以直观地看出Bessel光束被轴上圆形障碍物遮挡后逐步完成自重建,说明用LED非相干光作为光源具有自重建特性.实验上采用LED和轴棱锥元件产生Bessel光束,然后通过轴上圆形障碍物、轴上方形障碍物,并拍摄了不同位置处的截面光强分布图,证实了非相干光源产生Bessel光束的自重建特性.实验结果和模拟结果相符合.
Based on the Hankel wave theory,reconstruction property of Bessel beam generated by incoherent source is analyzed.The section light intensity distribution of Bessel beam after on-axis circular obstacle is simulated by optical design software ZEMAX.Light emitting diode(LED)has a certain spectrum width,therefore we describe it by using a continuous spectrum with a certain range of spectral width.From the simulation results we can see visually that Bessel beam gradually realizes the reconstruction after circular obstacles on-axial shelter.It is proved that LED has the reconstruction property.We use LED and axcion element to generate Bessel beam.This Bessel beam passes though an on-axis circular obstacle and an on-axis square obstacle.We take the pictures of the section light intensity distribution at different positions.The reconstruction properties of the LED incoherent source are verified.Experimental results accord well with the simulation results.