ZOOM LENS
PROBLEM TO BE SOLVED: To provide a compact zoom lens having an inexpensive and compact mechanism and suited to application to a portable apparatus (e.g. handheld transceiver). SOLUTION: The zoom lens is constituted of arranging three lens groups including a first lens group which is a negative funct...
Saved in:
Main Authors | , |
---|---|
Format | Patent |
Language | English |
Published |
22.06.2006
|
Subjects | |
Online Access | Get full text |
Cover
Loading…
Summary: | PROBLEM TO BE SOLVED: To provide a compact zoom lens having an inexpensive and compact mechanism and suited to application to a portable apparatus (e.g. handheld transceiver). SOLUTION: The zoom lens is constituted of arranging three lens groups including a first lens group which is a negative function lens set, a second lens group which is a positive function lens set and a third lens group which is a positive function lens set from a position close to a subject surface up to an image formation surface. Out of these lens groups, the second lens group should satisfy an expression 0.4<¾f2/fT¾<0.6. In the constitution, the whole length of the lenses can be suppressed, zooming power of two to three times can be provided only by one glass lens or two glass lenses at maximum and images of high quality can be provided by the thin, lightweight and inexpensive zoom lens. COPYRIGHT: (C)2006,JPO&NCIPI |
---|---|
Bibliography: | Application Number: JP20050118567 |