Multimode electronic calipers having ratiometric mode and simplified user interface

Abstract

A multimode electronic measuring instrument is provided that includes a ratiometric mode of operation. During the ratiometric mode, a desired dimension is established as a stored reference dimension “X ref ”. After the reference dimension is stored in memory, subsequent ratiometric measurement readouts will equal a current measurement distance “X curr ” divided by the reference dimension X ref . A ratiometric measurement according to this invention indicates the relationship of a current dimension to another readily changed (reference) dimension. The ratiometric mode of operation can be implemented in combination with conventional function caliper functions to provide a multimode caliper having a simple and intuitive user interface. Setting the reference dimension and interpreting the ratiometric measurement display are particularly easy, to facilitate intuitive understanding and operation.

1 . A multimode measuring instrument including, 
 a multimode simplified user interface for performing a ratiometric measurement, the user interface comprising,    a mode selecting arrangement operable to select a ratiometric measurement mode of operation;    an indicator portion for indicating the current mode of operation;    a reference-dimension setting element operable to set a reference dimension based on a relationship between two relatively moveable members of the measuring instrument at the time the reference-dimension setting element is operated; and    a numeric measurement indicating portion;    wherein,    when the reference dimension is set, the memory stores a reference dimension number that depends on the separation between the two relatively movable members of the measuring instrument, and when the separation between the two relatively movable members of the measuring instrument is changed, the numeric measurement indicating portion displays a number equivalent to dividing the dimension corresponding to the current separation between the two relatively movable members of the measuring instrument, by the reference dimension.