Answer #37

The correct answer is A. Lateral resolution is equal to the lateral beam width. The smaller the diameter of the beam width, the higher the resolution. Having a high resolution means being able to resolve objects that are close to each other. [insert lateral resolution illustration figure]. If two objects are in the same beam, they cannot be resolved as two objects; they will appear as one object. Thus a narrower beam will result in better lateral resolution.

All of the other choices increase the beam width or are unrelated. Spatial pulse length is related to axial resolution, not lateral resolution. Decreasing the frequency will increase the beam width and result in worse lateral resolution. Increasing the crystal diameter will increase the beam width as well. Frame rate relates to temporal resolution, not lateral resolution.