[3] [3] Wang F S, Tan J B, Zhao W Q. The optical probe using confocal technique for surface profile measurement［C］. SPIE, 2000, 4222：194-197.

[4] [4] Zhao W Q, Tan J B, QiuLR. Tri-heterodyneconfocal microscopewithaxialsuperresolutionandhigherSNR［J］. OpticsExpress, 2004, 12(21)：5191-5197.

[5] [5] Zhao W Q, Feng Z D, Qiu L R. A shaped annular beam tri-heterodyne confocal microscope with good anti-environmentalinterferencecapability［J］. ChinesePhysics, 2007, 16(6)：1624-1631.

[6] [6] Qiu LR, Liu D L, ZhaoWQ, et al. Real-time laser differential confocal microscopey without sample reflectivity effects［J］. OpticsExpress, 2014, 22(18)：21626-21640.

[8] [8] Wang F M, Xiao Y, Zhao M M, et al. 3D resolution improvement in confocal microscopy by mirror refection interferenceandfluorescenceemissiondifference［J］. OpticsandLasersinEngineering, 2020, 134：106198.