Patent · US Active

Afocal Galilean attachment lens with high pupil magnification

US7808718B2 · kind B2 · utility

2Cited by

6References

20Claims

0Family size

Assignee

FM-Assets, Pty Ltd · AU

Inventors

James Albert Frazier · Albuquerque, US
J. Brian Caldwell · Petersburg, US

Key dates

Filing date	Apr 27, 2009
Grant date	Oct 5, 2010
Priority date	—
Expiry date	Apr 27, 2029

Classification

Technology area (CPC G)Physics
CPC primaryG02B13/04
WIPO fieldOptics
WIPO sectorInstruments

Abstract

An afocal Galilean attachment lens is disclosed, with the lens comprising, along an optical axis, a first lens group with overall negative optical power and a second lens group with overall positive power. The first and second lens groups are arranged to define a Galilean configuration. The lens also has exit and an entrance pupils with respective diameters DEX and DEN that define a pupil magnification PM=DEX/DEN>4 and in some embodiments PM>10. The afocal Galilean attachment lens also has a length parameter defined LP>200 and in some embodiments LP>700. The extreme length of the afocal Galilean attachment allows for photographing or filming objects that are remote or otherwise hard to photograph while also providing a relatively large depth of field.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.