Patent ID: 6449859
Filing Date: 2002-09-17
Classification: G01C

Abstract:
A spirit level comprising:a body having a level face for setting a surface; at least one tubular bubble vial mounted in said body, said bubble vial having a longitudinal axis perpendicular to said level face, said level face arranged to be intermediate an end of said bubble vial and said surface to be set; and a mirror fixed to and entirely enclosed within said body which transfers an image of said bubble vial to a viewing plane parallel to said level face, said image including a bubble floating in said bubble vial and two graduation marks marked on opposite sides of a longitudinal midpoint of said bubble vial, said viewing plane being located on a viewing face of said body parallel to said level face, the ends of said bubble vial not extending beyond said level face and said viewing face, a transparent window element being located on said viewing face so that the image of said bubble vial can be viewed through said window element in a first range of viewing angles wherein a viewer can see said image transferred via said mirror, and in a second range of viewing angles wherein the viewer can see said image directly through said window element without said image being transferred via said mirror, wherein there is an unobstructed line of sight along a plane of said mirror.