Abstract: A method includes illuminating a material with first light along an optical path. The method also includes capturing an image of second light transmitted through the material using a first detector, where a first portion of the second light follows the optical path of the first light and a second portion of the second light diverges from the optical path. The method further includes capturing one or more measurements of third light using a second detector. The third light diverges from the optical path by a larger amount than the second portion of the second light, and the second detector is spaced apart from the first detector. In addition, the method includes determining one or more haze values associated with the material based on the image and the one or more measurements and at least one of storing and outputting the one or more haze values.

Abstract: A method includes measuring a caliper of a sheet of material using a caliper sensor having first and second sensor modules. The method also includes adjusting the caliper measurement based on a transverse displacement between a first sensor component in the first sensor module and a second sensor component in the second sensor module to generate a corrected caliper measurement. Adjusting the caliper measurement can include applying a corrector function that adjusts the caliper measurement based on the measured transverse displacement. The corrector function can be identified by repeatedly creating misalignment between the first and second sensor components, measuring a known distance using the caliper sensor, and identifying an error between the measurement of the known distance and the known distance.

Abstract: A method includes obtaining multiple images of a sheet of material. The images contain a first line projected onto a first side of the sheet and a second line projected onto a second side of the sheet. The images include (i) at least one first image containing the first line reflected off the first side of the sheet and the second line transmitted through the sheet and (ii) at least one second image containing the second line reflected off the second side of the sheet and the first line transmitted through the sheet. The method also includes identifying at least one point of intersection in the images where the lines intersect on the sheet. The method further includes identifying a caliper of the sheet using the at least one point of intersection.

Abstract: A method includes receiving multiple biased measurements associated with a property of a sheet of material, where the biased measurements correspond to multiple known sheet geometries. The method also includes determining an unbiased measurement associated with the property of the sheet using the biased measurements, where the unbiased measurement corresponds to a nominal sheet geometry. The method further includes storing and/or outputting the unbiased measurement. Determining the unbiased measurement could include performing regression using the biased measurements and their corresponding sheet geometries to identify an estimated value of the property of the sheet at the nominal sheet geometry. The biased measurements can be generated using one or more sensors, and the sheet may not be stabilized during the biased measurement generation. Additional sheet geometries can also be created, such as by varying a tilt angle, a curvature, and/or a position of the sheet.

Abstract: A method includes passing a web of material over a deflector having a backstep, where the backstep causes the web to deflect towards the deflector. The method also includes capturing measurements of one or more characteristics associated with the web at one or more locations downstream of the backstep. In addition, the method includes identifying a cross direction (CD) profile of machine direction (MD) tension on the web using the measurements. The method could further include generating a Coanda airflow between the web and the deflector. The measurements could include pressure measurements identifying air pressures in a space between the web and the deflector and/or deflection distance measurements identifying distances by which the web is deflected towards the deflector.

Abstract: A system includes multiple light emitting diodes (LEDs) and a light pipe configured to mix light from the LEDs and produce collimated light. The light pipe includes multiple reflective optical devices configured to reflect the collimated light at different angles. The light pipe also includes multiple outlet optical devices configured to selectively control exit of the reflected collimated light from the light pipe. The reflected collimated light has one or more controllable spectral characteristics and/or one or more controllable geometries of illumination.

Abstract: A method includes receiving a measurement associated with an anisotropy of a first surface and a measurement associated with an anisotropy of a second surface of a sheet of material. The method also includes adjusting an operating parameter associated with a headbox based on the measurements. The headbox is associated with manufacture of the sheet. The operating parameter could include a jet speed, a jet impingement angle, a jet thickness, a slice opening, and/or a slice apron projection. Adjusting the operating parameter could be based on a difference between a measured anisotropy of the first surface and a measured anisotropy of the second surface. For example, the operating parameter could be adjusted to achieve a desired difference between the measured anisotropy of the first surface and the measured anisotropy of the second surface. Multiple headboxes could be controlled, such as when different headboxes are used to produce different layers of a multi-layer sheet.

Abstract: A method includes obtaining multiple images of a sheet of material. The images contain a first line projected onto a first side of the sheet and a second line projected onto a second side of the sheet. The images include (i) at least one first image containing the first line reflected off the first side of the sheet and the second line transmitted through the sheet and (ii) at least one second image containing the second line reflected off the second side of the sheet and the first line transmitted through the sheet. The method also includes identifying at least one point of intersection in the images where the lines intersect on the sheet. The method further includes identifying a caliper of the sheet using the at least one point of intersection.

Abstract: A method includes measuring a caliper of a sheet of material using a caliper sensor having first and second sensor modules. The method also includes adjusting the caliper measurement based on a transverse displacement between a first sensor component in the first sensor module and a second sensor component in the second sensor module to generate a corrected caliper measurement. Adjusting the caliper measurement can include applying a corrector function that adjusts the caliper measurement based on the measured transverse displacement. The corrector function can be identified by repeatedly creating misalignment between the first and second sensor components, measuring a known distance using the caliper sensor, and identifying an error between the measurement of the known distance and the known distance.

Abstract: A system, apparatus and method are provided for adjusting an on-line appearance sensor system (OnLASS) for color and other appearance characteristic(s) of a web product produced during a production run of a web production system. The OnLASS is calibrated and its setting(s) are sent to a color error minimizer (CEM). The OnLASS measures a first appearance characteristic of the web product during the production run and the on-line measurement is sent to the CEM. After the production run, a second appearance characteristic of the web product is measured with an off-line appearance sensor system (OffLASS) and the off-line measurement is sent to the CEM. The CEM compares the on-line and off-line appearance measurements and adjusts at least one setting based on the comparison. The adjusted setting(s) are sent to the OnLASS.

Abstract: A system includes multiple light emitting diodes (LEDs) and a light pipe configured to mix light from the LEDs and produce collimated light. The light pipe includes multiple reflective optical devices configured to reflect the collimated light at different angles. The light pipe also includes multiple outlet optical devices configured to selectively control exit of the reflected collimated light from the light pipe. The reflected collimated light has one or more controllable spectral characteristics and/or one or more controllable geometries of illumination.

Abstract: A sheet of material is received at a sensor assembly, which includes a sensor operable to measure a property of the sheet. An air flow is generated that is substantially tangential to the sheet in order to at least partially control a position of the sheet relative to the sensor assembly. For example, the sheet may be associated with an upstream boundary layer of air and a downstream boundary layer of air. At least part of the air from the upstream boundary layer could be removed and used to provide an air flow forming at least part of the downstream boundary layer. Also, the air flow could be provided between a surface of the sensor assembly and the sheet to at least partially control a distance of the sheet from the surface of the sensor assembly and/or an angle at which the sheet passes the surface of the sensor assembly.

Abstract: A method includes illuminating a material with first light and capturing an image of second light transmitted through the material. The method also includes analyzing multiple regions of the image and determining one or more haze measurements associated with the material based on the analyzing. The method further includes storing and/or outputting the one or more haze measurements. Analyzing the multiple regions of the image may include summing pixel values in each region to produce a total pixel value for that region. The multiple regions of the image may include (i) a first region forming a first disc, (ii) a second region forming either a first annular region around the first region or a second disc larger than and including the first disc, and (iii) a third region forming either a second annular region around the second region or a third disc larger than and including the first and second discs.

Abstract: A system, apparatus and method are provided for adjusting an on-line appearance sensor system (OnLASS) for color and other appearance characteristic(s) of a web product produced during a production run of a web production system. The OnLASS is calibrated and its setting(s) are sent to a color error minimizer (CEM). The OnLASS measures a first appearance characteristic of the web product during the production run and the on-line measurement is sent to the CEM. After the production run, a second appearance characteristic of the web product is measured with an off-line appearance sensor system (OffLASS) and the off-line measurement is sent to the CEM. The CEM compares the on-line and off-line appearance measurements and adjusts at least one setting based on the comparison. The adjusted setting(s) are sent to the OnLASS.

Abstract: A method includes receiving a measurement associated with an anisotropy of a first surface and a measurement associated with an anisotropy of a second surface of a sheet of material. The method also includes adjusting an operating parameter associated with a headbox based on the measurements. The headbox is associated with manufacture of the sheet. The operating parameter could include a jet speed, a jet impingement angle, a jet thickness, a slice opening, and/or a slice apron projection. Adjusting the operating parameter could be based on a difference between a measured anisotropy of the first surface and a measured anisotropy of the second surface. For example, the operating parameter could be adjusted to achieve a desired difference between the measured anisotropy of the first surface and the measured anisotropy of the second surface. Multiple headboxes could be controlled, such as when different headboxes are used to produce different layers of a multi-layer sheet.

Abstract: A method includes receiving light from a material at a digital imaging device. The method also includes filtering the light into at least three spectral bands using a filter, where different regions of the filter pass different spectral bands. The method further includes measuring the light in each of the spectral bands and determining at least one color associated with the material using the measured light in the spectral bands. The different regions of the filter could include multiple masks (where each mask passes one of the spectral bands), different areas of a linear variable filter, and/or individual filters (where each individual filter passes one of the spectral bands). The digital imaging device could include a digital camera. The filter could be formed on a detector in the digital camera, and/or a component of the digital camera could be replaced with the filter.

Abstract: A method includes receiving a sheet of material at a sensor assembly. The sensor assembly includes a sensor configured to measure a property of the sheet. The method also includes stabilizing the sheet with respect to the sensor using a guide roller. Stabilizing the sheet includes using the guide roller to remove at least a portion of a first boundary layer of air moving towards the guide roller and to reform at least a portion of a second boundary layer of air moving away from the guide roller. For example, the guide roller could include a plurality of grooves or openings in a surface of the guide roller, or the guide roller could include a plurality of rings spaced apart from one another. Air could move from one side of the guide roller to another side of the guide roller through the grooves, through the openings, or between the rings.

Abstract: An apparatus includes at least one scanner. Each scanner includes a plurality of sensors, and each sensor is capable of measuring one or more characteristics associated with a portion of a substrate. The substrate has printing produced by a printing system. The apparatus also includes a controller capable of receiving at least some of the measurements from the plurality of sensors and determining a quality of the printing on the substrate using the received measurements. The substrate could represent paper, and the printing system could represent an offset printing system. At least one of the sensors may be in a fixed position and/or at least one of the sensors may be movable over part of a surface of the substrate. The determined quality of the printing could involve density, dot area, dot gain, contour sharpness, doubling, mottling, ghosting, misregister of different colored inks, slur, or improper positioning of the printing.

Abstract: Devices, systems and methods for controlling the coating of a sample are disclosed. The exemplary system may have a manufacturing device for providing a sample with one or more sample characteristics associated with one or more coating characteristics. The exemplary system may have a sample sensor for determining the one or more sample characteristics and a manufacturing controller for controlling the manufacturing device and controlling the one or more characteristics of the sample provided by the manufacturing device based on the determined one or more sample characteristics. The exemplary system may also have a coating device for providing coating to the sample with the one or more coating characteristics; a coating sensor for determining the one or more coating characteristics; and a coating controller for controlling the coating device and controlling the one or more characteristics of the coating provided by the coating device based on the determined one or more coating characteristics.

Abstract: Devices, systems and methods for controlling the coating of a sample are disclosed. The exemplary system may have a manufacturing device for providing a sample with one or more sample characteristics associated with one or more coating characteristics. The exemplary system may have a sample sensor for determining the one or more sample characteristics and a manufacturing controller for controlling the manufacturing device and controlling the one or more characteristics of the sample provided by the manufacturing device based on the determined one or more sample characteristics. The exemplary system may also have a coating device for providing coating to the sample with the one or more coating characteristics; a coating sensor for determining the one or more coating characteristics; and a coating controller for controlling the coating device and controlling the one or more characteristics of the coating provided by the coating device based on the determined one or more coating characteristics.