But the term "power" is also used to express the ability of a lens or other optical device to focus light.

So, just like film cameras, camcorders let you move your lens in and out to focus light.

Just behind the iris and pupil lies the lens, which helps to focus light on the back of the eye.

Just once the entire mirror-sail complex focused white light with enough energy that the cameras had to be pulled in.

Various techniques are used to track the Sun and focus light.

If there is no lens to focus light, the film will only turn white from receiving just the light.

The Court's decision focuses new light on living wills.

A steel hand mirror was sometimes used for reading, placed to focus light on the dark.

This, he said, may involve the way the eye focuses light of different colors.

The investigative board may now focus new light on these devices.