Zoom viewfinder
OwnerAlan E. Lewisinventor
Life of this patent
Estimating the term…
Abstract
A compact Galilean-type zoom finder suitable for compact cameras, and the like whose zoom ratio is about 2. The zoom finder is comprised of four units having negative, negative, positive and negative refractive powers in order from an object side. The first and the fourth lens units are fixed and the second and the third lens units are moved to perform zooming.
Claims11
A zoom finder comprising in order from an object side, a stationary first lens unit having negative refractive power, a movable second lens unit having negative refractive power, a movable third lens unit having positive refractive power and a stationary fourth lens unit having negative refractive power, said second and third units being movable for zooming.
A zoom finder comprising in order from an object side, a stationary first lens unit having negative refractive power, a movable second lens unit having negative refractive power, a movable third lens unit having positive refractive power and a stationary fourth lens unit having a negative refractive power, said second and said third units being moveable for zooming so that a space between said second lens unit and said third lens unit varies for zooming.
A zoom finder comprising in order from an object side, a stationary first lens unit having negative refractive power, a movable second lens unit having negative refractive power, a movable third lens unit having positive refractive power and a stationary fourth lens unit having negative refractive power, said second and said third units being moveable for zooming so that a space between said second lens unit and said third lens unit varies for zooming, wherein during zooming the image plane remains substantially constant, thus requiring no accommodation from the eye.
Dependencies are inferred from the claim text.