Fig. 1. Schematic of offset splicing.

Fig. 2. Excitation efficiency of each fiber mode versus offset point (offset direction: x axis).

Fig. 3. Auto-correlation function of specklegrams: (a) offset point in the x direction varies from −25μm to 25 μm; (b) offset point in the whole plane.

Fig. 4. Excitation ratio of (a) the third and (b) the seventh lower modes at different offset points.

Fig. 5. Specklegrams of two centrosymmetric offset points: (a) (6 μm, −5μm) and (b) (−6μm, 5 μm).

Fig. 6. (a) Data processing flow and (b) CNN architecture.

Fig. 7. Loss versus training epoch (loss, MSE in training set; and val_loss, MSE in validation set).

Fig. 8. Distribution of difference between the prediction label and validation label.

Fig. 9. Labeled offset points with d higher than 2 μm in the validation set.