The invention relates to a method and a measuring arrangement for determining roughness of paper or paperboard. The paper or paperboard surface is illuminated with collimated light substantially parallel with the normal of the paper or paperboard surface. An image is produced from the paper or paperboard surface by means of reflected optical radiation. The reflected optical radiation is used for producing an image of the paper or paperboard surface onto the pixels of the camera's detector surface, each of the pixels imaging an area in the order of micrometers of the paper or paperboard surface. An aperture provided in front of the camera is used for adjusting the depth of focus of the image, which affects the measurement of roughness. Roughness of paper or paperboard is measured on the basis of the intensity of the pixels on the camera's detector surface.
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a Continuation of International Application PCT/F100/00412 filed May 9, 2000 which designated the U.S. and was published under PCT Article 21(2) in English, and which is hereby incorporated herein in its entirety by reference.
A system for printing on a print media. The device comprises at least one high energy emitting device and a parameter estimation device. The parameter estimation device is coupled to the high energy emitting device and is adapted to classify the print media and quantify an amount of energy per time to be emitted by the high energy emitting device during printing.
An imaging apparatus includes a media support surface. A light source and a light detector are positioned in relation to a reflective surface such that when a sheet of print media covers the reflective surface, a reflected specular light component of a light beam is received by the light detector, and when the reflective surface is not covered, the reflective surface directs the reflected specular light component of the light beam away from the detector. The signal strength of the output from the light detector when receiving a diffuse light component reflected from the reflective surface is less than the signal strength of the output from the light detector when receiving the reflected specular light component that is reflected from a low reflectance print media.
