What Is Bipolar I?

Dipole lighting is a type of off-axis lighting, divided into horizontal bipolar (X-Dipole) and vertical bipolar (Y-Dipole), as shown in Figure 1. Two parameters are used to quantitatively describe bipolar illumination: c and i. c defines the distance between the center of the light source and the main optical axis; i defines the size of the light source. The larger c means that the farther the light source is from the main optical axis, the more obvious the effect of off-axis lighting. Horizontal bipolar illumination has high resolution for dense vertical lines, but poor resolution for horizontal lines. In contrast, vertical bipolar illumination has high resolution for dense horizontal lines, but poor resolution for vertical lines ^[1] .