Patent · US Expired

Safety device for telescope

US6698904B1 · kind B1 · utility

0Cited by
3References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 22, 2002
Grant dateMar 2, 2004
Priority date
Expiry dateFeb 22, 2022

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG02B23/00
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A ray of light incident via a pin hole (6) and a field stop (7) having a field of vision a predetermined angle larger than a telescope's actual field of vision that are disposed on an axis (5) in parallel to the optical axis (4) of the telescope is measured in intensity by a photoelectric element (8). When a quantity of light incident on the photoelectric element is larger than a predetermined quantity of light, a shutter (11) is inserted into an optical path of the telescope to cut off a ray of light going into the eyes of the observer. Since an incidence of a quantity of light in excess of a predetermined one into a field of vision a predetermined angle larger than the actual field of vision of the telescope will block the optical path of the telescope, a risk such as damage to the eyes of the observer can be eliminated to prevent an accident even when the observer erroneously observes a strong light-generating object such as the sun.

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