Hewlett-packard Development Company, L.p.

Hewlett-packard Company

Stuart A Scofield

Steven H Walker

Robert M Yraceburu

Bruce G Johnson

Elliott Downing

Matthew Douglas Reier

Cristopher Royce Jansson

Jefferson Patrick Ward

Alan Shibata

Huston W Rice

Daniel James Magnusson

Devin Scott Uehling

Ian Patrick Anderson

Robert Scott Beale

Jeffrey Castleberry

Catherine Elizabeth Gould

Tom McCue

Saurabh Shripad Bhide

Francisco Javier Gomez

Jonathon Cha Spafford

Joseph C O'Banion

Bartley Helms

Example implementations relate to print media stacks. In some examples, a device may include a sheet channel to guide a sheet of print media within the sheet channel above and separated in a vertical direction from a stack of printed media when the sheet of print media exits a print path of a printer. The device may include a plurality of clamps to control alignment of the sheet of print media on the stack of printed media when the sheet channel moves outboard from the sheet of print media to allow the sheet of print media to fall onto the stack of printed media, wherein the plurality of clamps sequentially pin the sheet of print media to the stack of printed media from a middle portion of the sheet of print media outward.

Print media alignments

A finisher apparatus includes an accumulator to register a print medium of a print job in preparation for a finishing operation, memory to store an attribute of the print job, and a processor coupled to the accumulator and the memory. The processor is to execute instructions. The instructions are to control the accumulator based on the attribute of the print job.

Print media accumulators controlled by print job attributes

In some examples, velocity and torque based media motor control may include ascertaining a velocity and torque for a feed roller motor associated with a feed roller, and ascertaining a velocity and torque for a drive roller motor associated with a drive roller that is to receive media from the feed roller. Further, velocity and torque based media motor control may include determining whether the torque for the drive roller motor is greater than a torque target. In response to a determination that the torque for the drive roller motor is greater than the torque target, the torque for the drive roller motor may be reduced to the torque target, and the torque for the drive roller motor may be maintained at the torque target.

Velocity and torque based media motor control

An example apparatus includes a non-transitory computer-readable medium with instructions stored thereon to perform apparatus component initialization sequences. The apparatus component initialization sequences include a full initialization sequence and a short initialization sequence, A processor is to execute the instructions to capture apparatus component state information, determine upon reception of a signal indicative of power on of the apparatus whether a position of an apparatus component is within a threshold of an expected position, perform the short initialization sequence if the position of the apparatus component is within the threshold and using the captured apparatus component state information.

Finishing line controllers to optimize the initialization of a printing device

A system having a disc carrier determines a location of the disc carrier based upon first and second specular signals from an optical sensing element, the first specular signal occurring when the incident light is not received within the opening and impinges a first portion of the optical sensing element and the second specular signal occurring when the incident light is received within the opening and impinges a second portion of the optical sensing element.

Media carrier

A system of classifying incoming media entering an inkjet printing mechanism identifies transparency media without requiring any special manufacturer markings. The media is first optically scanned using a blue-violet light at an initial intensity to obtain both diffuse and specular reflectance data. If useable, the data is compared with known values to classify the media so an optimum print mode tailored for the particular media is used. The early transparency detection system avoids time-consuming further steps trying to classify the media as photo media, plain paper, and the like, and facilitates fast printing of transparencies, which can be critical in the business environment when making last minute changes for a presentation. A printing mechanism constructed to implement this method is also provided.

Early transparency detection routine for inkjet printing

A system of classifying the type of incoming media entering an inkjet or other printing mechanism is provided to identify the media according to markings or identifying indicia on the back surface of the media opposite the printing surface which ultimately bears the printed image. The printing surface of the incoming media is optically scanned using a blue-violet light to obtain both diffuse and specular reflectance values. A spatial frequency signature for the incoming media is compared with known values for different types of media to classify the media according to major categories (transparencies, glossy photo media, premium or plain paper), and specific types of media within these categories (matte photo, premium, or high-gloss photo media). An optimum print mode is selected according to the determined media type to automatically generate outstanding images without bothersome user intervention. A printing mechanism constructed to implement this method is also provided.

Back-branding media determination system for inkjet printing

A system of classifying the type of incoming media entering an inkjet or other printing mechanism is provided to identify the media without requiring any special manufacturer markings. The leading edge of the incoming media is optically scanned using a blue-violet light to obtain both diffuse and specular reflectance values. A Fourier transform of these reflectance values generates a spatial frequency signature for the incoming media. The spatial frequency is compared with known values for different types of media to classify the incoming media according to major categories, such as transparencies, glossy photo media, premium paper and plain paper, as well as specific types of media within these categories, such as matte photo premium media and high-gloss photo media. An optimum print mode is selected according to the determined media type to automatically generate outstanding images without unnecessary user intervention. A printing mechanism constructed to implement this method is also provided.

Advanced media determination system for inkjet printing

A system of classifying incoming media entering an inkjet or other printing mechanism is provided to identify the media without requiring any special manufacturer markings. The incoming media is optically scanned using a blue-violet light to obtain both diffuse and specular reflectance data, from which a media signature is generated. The generated signature is compared with known signatures for different media types to classify the incoming media, and a corresponding print mode is selected. Finally, the selected print mode for the classified incoming media is stored for future reference. Thus, a consumer can teach the printing mechanism to recognize new types of media. For borderline media falling between two categories, the printer remembers which category was selected previously, and then applies the same print mode to the next borderline media to provide a visually consistent output. A printing mechanism constructed to implement this method is also provided.

Educatable media determination system for inkjet printing

A system of classifying incoming media entering an inkjet printing mechanism identifies the media without requiring any special manufacturer markings. The media is first optically scanned using a blue-violet light at an initial intensity to obtain both diffuse and specular reflectance data. If useable, the data is compared with known values for different types of media to classify the media so an optimum printmode tailored for the particular media type is used. If the initial data is unusable, successive scanning passes are preformed to find useable diffuse data, and if found, then to find useable specular data. During these successive passes, following an initial calibration scan for the media, each successive scan reduces the scanner intensity until reaching a minimum intensity. If upon reaching the minimum intensity, no useable data has been found, then a default printmode is selected. A printing mechanism constructed to implement this method is also provided.

Growing community of inventors

Battle Ground, WA, United States of America

Stuart A Scofield