lens

Not long ago, it was difficult to produce photographs of tiny creatures with every part in focus. That’s because the lenses that are excellent at magnifying tiny subjects produce a narrow depth of field.

The single-imaging optic of the mammalian eye offers some distinct visual advantages. Such lenses can take in photons from a wide range of angles, increasing light sensitivity. They also have high spatial resolution, resolving incoming images in minute detail.

If "the public looks at the condition of America's children largely through a negative lens," worries Child Trends[…], "it may be more difficult to […] promote child well-being."