# US 2016/0025642 A1 · Method and apparatus for automatic measurement of various qualities of printed sheets > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2016/0025642 A1 - Document ID: US20160025642A1 - Status: Published application - Kind: A1 - Application number: 14/877,880 - Filed: 2015-10-07 - Published: 2016-01-28 - Earliest claimed: 2014-01-09 - Assignees: Electronics for Imaging, Inc. - Applicants: Electronics for Imaging, Inc. - Inventors: Luc CHOULET - Web page: https://patentgrep.com/patent/US20160025642A1 ## CPC - G01N 21/86: Investigating moving sheets (G01N21/89 takes precedence) - B41J 11/0095: {Detecting means for copy material, e.g. for detecting or sensing presence of copy material or its leading or trailing end} - G01J 3/46: Measurement of colour; Colour measuring devices, e.g. colorimeters (measuring colour temperature G01J5/60) - G01N 21/255: {Details, e.g. use of specially adapted sources, lighting or optical systems} - G01N 21/55: Specular reflectivity - G01N 21/57: Measuring gloss - G01N 21/59: Transmissivity (G01N21/25 takes precedence) - G01N 2021/4719: {using a optical fibre array} - G01N 2021/4742: {comprising optical fibres} - G01N 2021/575: {Photogoniometering} - G01N 2021/8663: {Paper, e.g. gloss, moisture content} - G01N: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES (measuring or testing apparatus or processes other than immunoassay, involving enzymes or microorganisms C12M, C12Q) - B41J: TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS - G01J: MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY (light sources F21, H01J, H01K, H05B; investigating properties of materials by optical means G01N) ## Abstract Embodiments of the invention relate to the automatic measuring of such qualities of a printed sheet as reflectance excluding specular reflectance, reflectance including specular reflectance, e.g. gloss, transmittance, half-tone coverage, and the like. ## Claims ### Claim 1 A computer implemented method for automatic substrate detection, comprising: with a spectral sensor, automatically detecting what type of substrate is in a printer by measuring each of reflectance, transparency, and gloss from a plurality of angles using a light source comprising any of one visible light source similar to daylight or at least two colored light sources; responsive to said substrate detection, any of automatically loading a new technical setup into said printer and providing a warning to a user; wherein a combination of all information obtained by said measurements results in a unique ID for each substrate; and processing said measurements to estimate any of: substrate color [REFCLR]; substrate opacity [TRINT]; substrate gloss/mat scale [GULVL]; and substrate roughness or texture [TXTLVL]. ### Claim 2 (depends on 1) The method of claim 1, further comprising: measuring substrate color with a 45/0° geometry in a colorimetric mode using a three RGB sensor, or in spectral reflectance mode; computing colorimetric data from spectral reflectance data; and saving said data in CIEL*a*b* (D50/2°), or in another colorimetric space if needed. ### Claim 3 (depends on 1) The method of claim 1, further comprising: measuring substrate opacity with one band or with three bands; and saving resulting data as a measure of relative density. ### Claim 4 (depends on 1) The method of claim 1, further comprising: measuring substrate gloss with one sensor and one source light or with more than one sensor and/or light; and saving resulting data as a measure of relative density and/or relative intensity and/or gloss/unit, standardized after an internal calibration with an official standard. ### Claim 5 (depends on 1) The method of claim 1, further comprising: measuring substrate roughness or texture with one D sensor and a uniform light source in the visible spectrum or a 2D sensor and a uniform light source in the visible spectrum. ### Claim 6 (depends on 1) The method of claim 1, further comprising: finding a similar or nearest media type by comparison with existing values saved in a data base, based upon the values [REFCLR, TRINT, GULVL, TXTLVL] measured for a medium. ### Claim 7 (depends on 6) The method of claim 6, further comprising: using a kd-tree algorithm to find said similar or nearest media type. ### Claim 8 An apparatus for automatic substrate detection, comprising: a spectral sensor for automatically detecting what type of substrate is in a printer by measuring each of reflectance, transparency, and gloss from a plurality of angles using a light source comprising any of one visible light source similar to daylight or at least two colored light sources; a processor configured for, responsive to said substrate detection, any of automatically loading a new technical setup into said printer and providing a warning to a user; said processor configured for a combination of all information obtained by said measurements to generate a unique ID for each substrate; and said processor configured for processing said measurements to estimate any of: substrate color [REFCLR]; substrate opacity [TRINT]; substrate gloss/mat scale [GULVL]; and substrate roughness or texture [TXTLVL]. ### Claim 9 (depends on 8) The apparatus of claim 8, further comprising: said processor measuring substrate color with a 45/0° geometry in a colorimetric mode using a three RGB sensor, or in spectral reflectance mode; said processor computing colorimetric data from spectral reflectance data; and said processor saving said data in CIEL*a*b* (D50/2°), or in another colorimetric space if needed. ### Claim 10 (depends on 8) The apparatus of claim 8, further comprising: said processor measuring substrate opacity with one band or with three bands; and said processor saving resulting data as a measure of relative density. ### Claim 11 (depends on 8) The apparatus of claim 8, further comprising: said processor measuring substrate gloss with one sensor and one source light or with more than one sensor and/or light; and said processor saving resulting data as a measure of relative density and/or relative intensity and/or gloss/unit, standardized after an internal calibration with an official standard. ### Claim 12 (depends on 8) The apparatus of claim 8, further comprising: said processor measuring substrate roughness or texture with one D sensor and a uniform light source in the visible spectrum or a 2D sensor and a uniform light source in the visible spectrum. ### Claim 13 (depends on 8) The apparatus of claim 8, further comprising: said processor finding a similar or nearest media type by comparison with existing values saved in a data base, based upon the values [REFCLR, TRINT, GULVL, TXTLVL] measured for a medium. ### Claim 14 (depends on 13) The apparatus of claim 13, further comprising: said processor using a kd-tree algorithm to find said similar or nearest media type.