The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 25, 1990
Filed:
Aug. 18, 1988
Jerry T Kegelman, St. Louis County, MO (US);
Joseph C Kroutil, St. Louis County, MO (US);
Rodney Lusk, St. Louis County, MO (US);
McDonnell Douglas Corporation, St. Louis, MO (US);
Abstract
An apparatus for measuring the distance between two locations on a surface within a cavity includes a sheath which is inserted into the cavity and a scope which extends through the sheath. Through the scope, one from a remote location may observe the surface as well as reference marks which appear within the field of view on each side of the optical axis. These reference marks are aligned with opposite sides of that which is to be measured on the surface. In addition, the apparatus includes two point sources of light located along opposite sides of the scope with each source being located behind a lens that is presented toward the surface which is observed within the field of view. The lenses project their sources of light into the field of view as rays which come into focus on the surface. Under these conditions it is possible to ascertain the distance between the two regions of the surface at which the reference marks appear; that is the distance between the opposite sides of that which is under observation.