In order to improve the energy of the pulsed laser passing through the hysteroscope, three lens coupling scheme was adopted was adopted to improve the coupling efficiency. The theoretical analysis and experimental validation were carried out. The results show that the coupling efficiency is increased by about 14%. The experimental data, which indicates that the pulsed laser is more powerful than the pulsed laser, is more efficient than the pulsed laser. A better photoacoustic imaging effect is obtained after passing through our proposed coupling module. The study is expected to improve the effect of photoacoustic imaging technology in endometrial application, and will be able to be applied as an auxiliary tool for the detection of endometrial and other diseases in the clinic.