Patent ID: 7913995

Claim:
A method for non-contact measurement of a media stack in an image production device, comprising: detecting the position of an unfluffed media stack using one or more sensors; setting a desired media stack height by changing a media elevator position using a media elevator control unit based on the detected unfluffed media stack position; determining if printing and fluffing has started, wherein if it is determined that printing and fluffing has started, detecting a number and thickness of the fluffed media sheets using the one or more sensors; calculating a sum of the fluffed media sheet thicknesses; determining if the calculated sum of the fluffed media sheet thicknesses is below a predetermined threshold, wherein if it is determined that the calculated sum of the fluffed media sheet thicknesses is below the predetermined threshold, setting the desired media stack height by changing the media elevator position using the media elevator control unit based on the calculated sum of the fluffed media sheet thicknesses, wherein a first voltage threshold V L and a second voltage threshold V H are used to calculate the fluffed media sheet thicknesses such that each time a signal from a sensor drops below V L , the number of pixels are counted and if the signal from the sensor then exceeds V H , the number of pixels are multiplied by a pixel pitch to obtain the fluffed media sheet thickness.