Patent ID: 6748666
Filing Date: 2004-06-15
Classification: G01C

Abstract:
A spirit level comprising:a body having a level face of rectangular shape for setting a surface, said level face having a widthwise axis and a lengthwise axis; 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, the image of said bubble vial having a longitudinal axis which is parallel to said lenghtwise axis of said level face, 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.