Figure 2-48. Magnification by reading glass-object within focal length.

TM 9-258

distant object strike the face of a divergent lens in almost

2-25.

Image Formation by Divergent Lens.

parallel rays and, after refraction, are diverted by the lens

away from the axis (fig 2-49). In looking along the paths

a. Type of Image. Divergent lenses can form only

of the rays, the observer sees an apparent intersection of

virtual images which are erect and smaller than the

the rays at a point on the same side of the lens as the

object. This holds true regardless of the distance of the

object. The point where the rays appear to intersect is

object from the lens. Divergent lenses are termed

the focal point. It is backward continuation of the

negative because they will produce only an image

emergent rays as imaginary lines. As the observer looks

smaller than the object, they produce only virtual images,

along the paths of these rays, he sees the virtual (not

and they deviate the light outward. The virtual images

real)--image of the object located inside the intersection

formed by them are always on the same side of

of these imaginary continuation lines (fig 2-50).

b. Plotting the Image. Light rays from a very

2-35