Patent ID: 7306524

Claim:
A device for measuring a property of a surface comprising: a housing with a passage defined therein; a plurality of detection units disposed within said passage to detect traversal of said passage by an object directed therethrough, wherein said passage includes a first pair of detection units disposed toward a first end of said passage and separated by a first predetermined distance and a second pair of detection units disposed toward an opposing end of said passage and separated by a second predetermined distance; and a control unit disposed on said housing and coupled to said detection units to determine deceleration of said object through said passage due to said surface, wherein said control unit includes: a processor to determine said deceleration in accordance with detections from said detection units and to produce based on said deceleration a resultant measurement value indicative of said surface property and in relation to a predetermined scale, wherein said resultant measurement value pertains to a total distance said object travels on said surface in response to an initial predefined reference velocity, and wherein said processor includes: a first interval module to measure elapsed time for said object to travel between said first pair of detection units; and a second interval module to measure elapsed time for said object to travel between said second pair of detection units; and a display to display said resultant measurement value.