Fig. 1. Optical path structure of an inverted bright field biological microscope

Fig. 2. Some images with different size from OFC dataset

Fig. 3. Cells of different classifications. (a) Class ‘without_division’; (b) class ‘with_division’

Fig. 4. Network architecture of DetectNet

Fig. 5. Convolutional module

Fig. 6. Residual block

Fig. 7. CSP module

Fig. 8. Attention module

Fig. 9. Learning rate and loss curves. (a) Learning rate; (b) loss

Fig. 10. Visualization of cell detection results

Fig. 11. P-R curves of cell detection results under different IoU thresholds. (a) Class ‘with_division’; (b) class ‘without_division’