Patent ID: 9160892
Filing Date: 2015-10-13
Classification: B41J,H04N

Abstract:
1. A print head protection system for use in connection with an inkjet printer having an inkjet print head, the print head being adapted for elevating, and a media sheet having a lead edge and a trail edge, the media sheet moving in a process direction along a process path, the print head protection system comprising: a projector disposed upstream of the print head for projecting a reference pattern onto the media sheet as a projected pattern, the projected pattern being at a predetermined position along the process path; an imaging camera for capturing a digital image of the projected pattern at the predetermined position; an analyzer for comparing the digital image of the projected pattern with the reference pattern, detecting moiré fringes, analyzing the moiré fringes for media distortion, and creating an error signal when distortion exceeds an acceptable limit; and a mitigation control operative to mitigate print head damage in response to the signal.