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Title:
SCANNING INTERFACE WITH DUAL-LAYER GLASS SUBSTRATES
Document Type and Number:
WIPO Patent Application WO/2018/048388
Kind Code:
A1
Abstract:
In one example in accordance with the present disclosure, a scanning interface device is described. The scanning interface device includes a scan glass substrate divided into a sheet feed scan zone and a flatbed scan zone. A cover glass substrate is disposed over the sheet feed scan zone of the scan glass substrate. A media ramp directs media towards an output tray from the sheet feed scan zone. An image of the media passing over the cover glass substrate is captured by a scanner below the scan glass substrate.

Inventors:
SMITH RYAN M (US)
OCTAVIO VALENZUELA-RIVAS RENE (US)
HILL EDWARD ANTHONY (US)
JOHNSON CRAIG T (US)
Application Number:
PCT/US2016/050477
Publication Date:
March 15, 2018
Filing Date:
September 07, 2016
Export Citation:
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Assignee:
HEWLETT PACKARD DEVELOPMENT CO (US)
International Classes:
H04N1/00
Domestic Patent References:
WO2008035751A12008-03-27
Foreign References:
US20130003147A12013-01-03
US20070103741A12007-05-10
US20130003145A12013-01-03
US6252684B12001-06-26
US20160198062A12016-07-07
US20060029296A12006-02-09
US20130001400A12013-01-03
Attorney, Agent or Firm:
GARDINER, Austin et al. (US)
Download PDF:
Claims:
CLAIMS

WHAT IS CLAIMED IS:

1 . A scanning interface device comprising:

a scan glass substrate divided into a sheet feed scan zone and a flatbed scan zone;

a cover glass substrate disposed over the sheet feed scan zone of the scan glass substrate;

a media ramp to direct media towards an output tray from the sheet feed scan zone;

a media transition to guide the media passing over the cover glass substrate onto the media ramp;

wherein an image of the media passing over the cover glass substrate is captured by a scanner below the scan glass substrate.

2. The device of claim 1 , further comprising a calibration strip laminated between the scan glass substrate and the cover glass substrate, wherein the calibration strip comprises a slot through which the scanner, which is below the scan glass substrate, captures the image of the media that passes over the cover glass substrate.

3. The device of claim 1 , further comprising a recess on a surface of the scan glass substrate on a same side as the scanner to:

move the scanner closer to the scan glass substrate when scanning in a sheet feed scan mode as compared to when scanning in a flatbed scan mode; and

shift a focal point of the scanner when in the sheet feed scan mode.

4. The device of claim 1 , wherein the scan glass substrate and the cover glass substrate are sized to scan an A3-sized media.

5. The device of claim 1 , wherein the scan glass substrate is no greater than 3 millimeters thick.

6. A scanning system comprising:

a scanning interface device comprising:

a scan glass substrate;

a calibration strip laminated between the scan glass substrate and a cover glass substrate, wherein the cover glass substrate covers just a sheet feed scan zone of the scan glass substrate; and

a bezel disposed around a perimeter of the scan glass substrate to hold the scan glass substrate in place, wherein the bezel comprises a media ramp to:

define a sheet feed scan zone and a flatbed scan zone of the scan glass substrate; and

direct the media towards an output tray when scanning in a sheet feed scan mode; and

a first scanner disposed below the scan glass substrate to capture an image of a first side of the media passing over the scanner;

wherein as the media passes over the cover glass substrate, an image of the first side of the media is captured by the first scanner, which is below the scan glass substrate.

7. The system of claim 6, further comprising a second scanner disposed above the scan glass substrate to capture an image of a second side of the media as the media passes below the second scanner and wherein both the first scanner and the second scanner are calibrated using opposite sides of the calibration strip.

8. The system of claim 6, wherein a portion of the calibration strip overlaps a leading edge of the media ramp to provide a transition from the sheet feed scan zone to the output tray.

9. The system of claim 6, wherein the system does not include a transparent polymer output media ramp,

10. The system of claim 6, further comprising a spacer on a surface of the scan glass substrate in the flatbed scan zone and on a same side as the scanner to:

move the scanner farther from the scan glass substrate when scanning in a flatbed scan mode as compared to when scanning in a sheet feed scan mode; and

shift a focal point of the scanner when in the flatbed scan mode,

1 1 . A scanning interface device, comprising:

a scan glass substrate divided into a sheet feed scan zone and a flatbed scan zone;

a calibration strip laminated between the scan glass substrate and a cover glass substrate, which cover glass substrate is disposed just over the sheet feed scan zone of the scan glass substrate;

a bezel disposed around a perimeter of the scan glass substrate to hold the scan glass substrate in place, wherein the bezel comprises a media ramp; and

a media transition between the sheet feed scan zone and the output media ramp;

wherein an image of media passing over the cover glass substrate is captured by a scanner below the scan glass substrate through a slot in the calibration strip.

12. The device of claim 1 1 , wherein the calibration strip is sealed between the scan glass substrate and the cover glass substrate to prevent contamination of the calibration strip.

13. The device of claim 1 1 , wherein:

ihe media transition is formed from a portion of the calibration strip; and

a portion of the calibration strip overlaps a leading edge of the output media ramp.

14. The device of claim 1 1 , wherein:

the media transition is distinct from the calibration strip; and a portion of the media transition over a leading edge of the output media ramp.

15. The device of claim 1 1 , further comprising a recess in a side of the scan glass substrate in the sheet feed scan zone such that when the scanner is in a sheet feed scanning mode the scanner is disposed closer to the scan glass substrate than when the scanner is in a flatbed scanning mode in the flatbed scan zone.

Description:
SCANNING INTERFACE WITH DUAL-LAYER GLASS SUBSTRATES

BACKGROUND

[0001 ] Image devices such as scanners are used to create digital copies of documents or images. Different types of scanners perform different types of scanning operations. For example, in flatbed scanning, a scanner moves under a stationary document. By comparison, in sheet feed scanning, the scanner is stationary as the document to be captured moves across the scanner. Such scanners can be standalone scanners or can be incorporated into

multifunctional printers.

BRIEF DESCRIPTION OF THE DRAWINGS

[0002] The accompanying drawings illustrate various examples of the principles described herein and are part of the specification. The illustrated examples are given merely for illustration, and do not limit the scope of the claims.

[0003] Fig. 1 A is a diagram of a device in which the scanning interface device with dual-layer glass substrates is installed, according to an example of the principles described herein.

[0004] Fig. 1 B is a cross-sectional diagram of a scanning interface device with dual-layer glass substrates, according to an example of the principles described herein.

[0005] Fig. 2 is a cut-away isometric view of a scanning system with a scanning interface device with dual-layer glass substrates, according to an example of the principles described herein. [0006] Fig. 3 is an exploded view of a scanning interface device with dual-layer glass substrates, according to an example of the principles described herein.

[0007] Fig. 4 is a cross-sectional diagram of a portion of a scanning system with a scanning interface device with dual-layer glass substrates, according to an example of the principles described herein.

[0008] Fig. 5 is a cross-sectional view of a portion of a scanning system with a scanning interface device with dual-layer glass substrates, according to an example of the principles described herein.

[0009]Throughout the drawings, identical reference numbers designate similar, but not necessarily identical, elements.

DETAILED DESCRIPTION

[00010] Imaging devices such as scanners create digital images of documents. There are many types of scanners. For example, in a sheet feed scanner, an automatic document feeder (ADF) moves media past the scanner, while the scanner is in a fixed position. A sensor on the scanner then captures an image of the side of the media facing the scan sensor of the scanner.

[00011 ] Another example of a scanner is a flatbed scanner. In this example, objects to be scanned are placed on a top surface of a transparent scan platen, in this example, the scanner, and corresponding scan sensor travel underneath the platen to capture the digital image of the object, in some examples, one scanner can be used to carry out various types of scanning. For example, a scanner can be locked in one position to perform sheet feed scanning. That same scanner can be moved throughout a different zone to carry out flatbed scanning.

[00012] While such scanners offer a variety of scan operations, some characteristics limit their implementation. For example, in a sheet feed scan operation, an ADF system takes media from an input tray, to the zone where scanning occurs, i.e., past the stationary scanner, and onto an output tray. The input tray and output tray may be oriented such that the path of the media forms a "C" shape. In this operation, there is an interface between the platen where the scanning occurs and the output tray of the ADF system. This transition between the platen and the output tray can lead to complications with the function of the scanning device. For example, a media ramp may be used to guide the media onto the output tray. However, if the leading edge of the media ramp is higher than the platen on which scanning occurs, media could collide with the leading edge leading to a jam of the scanning system. Different options have been presented to effectuate a smooth transition from the zone where sheet feed scanning occurs onto the output tray, each having various complications.

[00013] To address this complication, some scanning systems implement a two-platen configuration where one platen for sheet feed scanning is separated from a platen for flatbed scanning. A media ramp between the two is placed such that the leading edge of the media ramp is lower than a top surface of the sheet feed scan platen. Doing so reduces the likelihood of a media jam, as the media is not likely to impact with the leading edge of the media ramp. However, this system has a sealed joint of the media ramp against the sheet feed glass platen and the flatbed glass platen. Such a sealed joint prevents contamination from reaching the scanner device that is beneath the platen. This joint is not mechanically robust as joining on such a small scale is a difficult mechanical process. That is, when pressure is applied, for example, when a book is pressed against the platen, or during cleaning, the joint could deflect resulting in at least image quality reduction, such as streaks, as contaminants could enter the sealed portion of the scanning the system. This system could also lead to complete failure of the joint, thus rendering the scanning system unusable.

[00014] In another solution, a single glass platen is used for both sheet feed scanning and flatbed scanning, in this example, a media ramp is disposed on top of the single glass platen and a transparent polymer guide is disposed over the sheet feed scan portion and over a leading edge of the media ramp. In this example, scanning occurs through the transparent polymer guide, and the transparent guide offers a smooth transition from the sheet feed scanning zone onto the media ramp. However, such a transparent polymer guide can be damaged during operation or cleaning. For example, the polymer guide can be scratched, with the scratches impacting the image quality. Moreover, customers may confuse the polymer guide as packaging material that is to be removed, thus rendering the device unusable,

[00015] Accordingly, the present specification describes a scanning interface device and system that alleviate these issues and others. Specifically, a cover glass is disposed over a calibration strip and the scan glass such that scanning occurs through two layers of glass. The calibration strip is also protected by the cover glass, thereby enhancing image quality as the calibration strip is protected against contamination. The cover glass also provides a durable, long lasting clear surface through which scanning occurs. As such, the life of the scanning device interface and the associated scanning system as a whole is increased.

[00016] In some examples, the calibration strip that is disposed between the glass substrates can be disposed over a leading edge of the media ramp thus forming a smooth transition from the sheet feed zone of the scanning system to the output tray of the ADF system, thereby enhancing the

smoothness along the media path and reducing the likelihood of a media jam.

[00017] Specifically, the present specification describes a scanning interface device. The scanning interface device includes a scan glass substrate that is divided into a sheet feed scan zone and a flatbed scan zone. A cover glass substrate of the scanning interface device is disposed over the sheet feed scan zone portion of the scan glass substrate, A media ramp guides media onto an output tray and a media transition guides the media from the sheet feed scan zone to the media ramp. During scanning, an image of the media passing over the cover glass substrate is captured by a scanner below the scan glass substrate.

[00018] The present specification also describes a scanning system.

The scanning system includes a scanning interface device that includes a scan glass substrate and a calibration strip laminated between the scan glass substrate and a cover glass substrate. The scanning interface device also includes a bezel disposed around a perimeter of the scan glass

substrate. The bezel holds the scan glass substrate in position and includes a media ramp. The media ramp defines a sheet feed scan zone and a flatbed scan zone of the scan glass substrate and directs media towards an output tray when scanning in a sheet feed scan mode. The system also includes a first scanner disposed below the scan glass substrate to capture an image of a first side of media passing over the scanning interface device. As before, as the media passes over the cover glass substrate, an image of the first side of the media is captured by the first scanner, which is below the scan glass substrate.

[00019] The present specification also describes a scanning interface device. The scanning interface device includes a scan glass substrate divided into a sheet feed scan zone and a flatbed scan zone. A calibration strip is laminated between the scan glass substrate and a cover glass substrate that covers just the sheet feed scan zone of the scan glass substrate. The scanning interface device also includes a bezel disposed around a perimeter of the scan glass substrate to hold the scan glass substrate in place. The bezel includes a media ramp. A media transition of the scanning interface device is disposed between the sheet feed scan zone and the media ramp. An image of media passing over the cover glass substrate is captured by a scanner below the scan glass substrate through a slot in the calibration strip.

[00020] In one example, using such a glass laminated scan interface device 1 ) provides a robust scanning interface that doesn't excessively deflect under applied loads; 2) alleviates a difficult to seal glass to media ramp joint; 3) enhances image quality by alleviating the scanning of media through a transparent polymer media guide; 4) enhances the life of the scanning interface and corresponding scanning system as all optical surfaces are glass that do not degrade as quickly as other materials like polymer; 5) allows for a reduction of the size of the overall scanning system; 6) creates a smoother media transition from the sheet feed scan zone towards the output tray; and 7) allows for larger glass platens to be used for a given glass thickness by providing support around the entire perimeter of the platen. However, it is contemplated that the devices disclosed herein may address other matters and deficiencies in a number of technical areas.

[00021 ] As used in the present specification and in the appended claims, the term "glass" as in a "glass substrate" refers to any material that allows for the transmission of light where the surface hardness is equal to or greater than glass. Examples of glass include sapphire glass among others. Moreover, while the present specification describes glass as the substrate, the substrate may be various types of material that allow for the transmission of light including crystal.

[00022] As used in the present specification and in the appended claims, the term "a number of or similar language is meant to be understood broadly as any positive number including 1 to infinity.

[00023] In the following description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of the present systems and methods. However, the present apparatus, systems, and methods may be practiced without these specific details. Reference in the specification to "an example" or similar language indicates that a particular feature, structure, or characteristic described in connection with that example is included as described, but may not be included in other examples.

[00024] Fig. 1A is a diagram of a device (100) in which the scanning interface device is installed and Fig. 1 B is a cross-sectional diagram of the scanning interface device (102) with dual-layer glass substrates, according to an example of the principles described herein. The device (100) includes a scanner (104) to create a digital image of media that passes over the scanner (104) that includes images or text. Accordingly, the device (100) includes a device housing (108) that retains the scanner and supports the scan glass substrate (108). The scanner (104) is disposed beneath the scan glass substrate (108) to protect it from contamination and to otherwise prevent debris from interacting with the scanner (104). Such debris can affect the scanner's (104) ability to provide quality digital reproductions of the media with text or images. [0002S] As described above, in some examples a single scanner (104) can be used to perform different kinds of scanning. Specifically, the scanner (104) can perform sheet feed scanning and flatbed scanning, each scanning mode being performed in a different zone. Accordingly, the device housing (106) also houses a drive system (124) that moves the scanner (104) from beneath the sheet feed scan zone (1 10) of the scan glass substrate (108) wherein the scanner (104-1 ) is in a sheet feed scanning mode to a position beneath a flatbed scan zone (1 1 1 ) of the scan glass substrate (108) wherein the scanner (104-2) is in a flatbed scanning mode. The scanner in the sheet feed scanning zone (1 10) is identified by a solid lines and the reference number (104-1 ) whereas the scanner in the flatbed scanning zone (1 1 1 ) is indicated in dashed lines and the reference number (104-2).

[00026] During flatbed scanning an object, such as a book, is laid flat on the scan glass substrate (108) and the scanner (104) moves underneath the object to create the digital image. By comparison, during sheet feed scanning, the scanner (104) is stationary and the media passes over the scanner (104), [00027] To carry out sheet feed scanning, the device (100) includes an automatic document feed (ADF) system with various components. For example, the ADF system includes an input tray (1 14) that holds media to be scanned and an output fray (1 16) that collects media that has been scanned. The ADF system also includes a media transport system that includes motors, belts, and/or paper picking mechanisms, along with other components that facilitate the movement of the media from the input tray (1 14) to the sheet feed scan zone (1 10), and then onto the output tray (1 16). During sheet feed scanning, the media moves along the media path (1 18) while the scanner (104) remains stationary and captures an image of the downward facing side of the media as it passes above the scanner (104).

[00028] As indicated in Fig. 1 A, the input tray (1 14) and the output tray (1 16) of the ADF system may be stacked on top of one another such that the media path (1 18) forms a "C" shape, in this example, a scan interface device serves to guide the media from the sheet feed scan zone (1 10) towards the media ramp (120) to be ultimately deposited on the output tray (1 16). The scan interface device (102) is illustrated in detail in Fig. 1 B.

[00029] Specifically, the scan interface device (102) includes the transparent scan substrate (108) which is divided into a sheet feed scan zone (1 10) and a flatbed scan zone (1 1 1 ). In other words, the scan glass substrate (108) serves as a substrate on which an object can be placed during flatbed scanning and also serves as a substrate over which the media passes during sheet feed scanning. Using a single glass substrate to provide both the scanning surface for the flatbed scanning and sheet feed scanning improves the robustness of the scanning surface. For example, instead of having two substrates that rely on a joint, the single glass surface is stronger and the lack of such a joint increases its resistance to deflection. Moreover, a single glass substrate is more cost effective to manufacture than multiple glass substrates.

[00030] The scanning interface device (102) also includes a cover glass substrate (122) disposed over just the sheet feed zone (1 10) portion of the scan glass substrate (108), In other words, during scanning in a sheet feed mode the scanner (104) captures an image of the media through two sheets of glass, i.e., the scan glass substrate (108) and the cover glass substrate (122). Doing so provides for a smooth transition from the sheet feed scan zone (1 10) to the adjacent media ramp (120) without using a polymer transparent material, which polymer transparent material has a shorter life span and is more prone to damage than the cover glass substrate (122).

[00031 ] Fig. 1 B also depicts the media transition (134) that smoothly guides the media along the media path (1 18) over the sheet feed scan zone (1 10). Without the smooth media transition (134), incoming media along the media path (1 18) may collide with a leading edge of the media ramp (120), which could result in scanning artifacts in the digital image, and/or jamming of the system. Accordingly, the smooth, and in some examples curved, media transition (134) prevents such collision thus simplifying the media movement through the ADF during sheet feed scanning.

[00032] Fig. 2 is a cut-away isometric view of a scanning system (226) with a scanning interface device (Fig. 1A, 102) with dual-layer glass substrates, according to an example of the principles described herein. The scanning system (228) may form part of, or be integrated with, the device (Fig. 1A, 100) described above in Fig. 1 A. The scanning system (228) includes at least a first scanner (104) and as will be described in an example below, may include a second scanner. The first scanner (104) is disposed beneath the scan glass substrate (108) in the device housing (106) so as to be protected from damage, debris, or other contamination. This is because the scanner (104) includes instrumentation and other components that are sensitive and/or fragile and may be damaged by frequent user contact or contact with environmental elements. As described above, the scanner (104) can reside under the flatbed scan zone (Fig. 1A, 1 1 1 ) defined in part by the media ramp (120) where the scanner (104) performs flatbed scanning through just the scan glass substrate (108). The scanner (104) can then move towards the sheet feed scan zone (Fig. 1A, 1 10) defined in part by the media ramp (120) where the scanner (104) performs sheet feed scanning through both the scan glass substrate (108) and the cover glass substrate (122),

[00033] The scanning system (226) also includes the scanning interface device (Fig. 1A, 102) which includes the scan glass substrate (108) and the cover glass substrate (122). The scanning interface device (Fig. 1 A, 102) also includes a bezel (228) around a perimeter of the scan glass substrate (108). The bezel (228) holds the scan glass substrate (108) in place against the device housing (108).

[00034] Fig, 2 also depicts how using a single scan glass substrate (108) for both sheet feed scanning and flatbed scanning can lead to improved scanning. That is, the scan glass substrate (108) is supported around all edges of its perimeter against the device housing (106) as opposed to having certain edges of the scan glass substrate cantilevered and being supported on less than all edges of the perimeter of the scan glass substrate (108). This additional support provides additional rigidity to the scan glass substrate (108) and in some cases allowing for a scan glass substrate (108) having a reduced thickness. For example, in some cases, a thinner scan glass substrate (108), specifically no greater than 3 millimeters thick, can be used. [0003S] Using a scan glass substrate (108) that is no greater than 3 millimeters expands the scanning capability of the system (228), For example, certain scanners (104) such as contact image scanners have a short focal distance and cannot scan through glass substrates that are greater than 3 millimeters thick. However, a cantiievered substrate less than 3 millimeters thick is structurally unsound. As a result, large scan substrates, i.e., to accommodate an A3 media size, could not be implemented robustly in a cantiievered system. Accordingly, in some examples of the present system (226), the scan glass substrate (108) may be sized to accommodate A3-sized media in both a length and width direction and the cover glass substrate (108) may be sized to accommodate the A3-sized media in at least a width direction.

[00036] Returning to the bezel (228), the bezel (228) includes a crossbar member that defines the media ramp (120). The media ramp defines the sheet feed scan zone (Fig. 1 A, 1 10) and the flatbed scan zone (Fig. 1 A, 1 1 1 ) of the scan glass substrate (108). For example, as depicted in Fig. 2, the sheet feed scan zone (Fig. 1A, 1 10) is that portion to the left of the media ramp (120) and the flatbed scan zone (Fig. 1 A, 1 1 1 ) is that portion to the right of the media ramp (120). The media ramp (120) also directs the media towards an output tray (Fig. 1A, 1 16) when scanning in a sheet feed scan mode.

[00037] In some examples, the scanning interface device (Fig. 1A, 102) includes a calibration strip laminated between the scan glass substrate (108) and the cover glass substrate (122). Fig. 3 is an exploded view of a scanning interface device (102) with dual-layer glass substrates specifically illustrating the calibration strip (330) laminated between the scan glass substrate (108) and the cover glass substrate (122), according to an example of the principles described herein. The scanning interface device (102) includes the scan glass substrate (108) that is divided into the sheet feed scan zone (Fig. 1A, 1 10) and the flatbed scan zone (Fig. 1A, 1 1 1 ) and the cover glass substrate (122) that is disposed just over the sheet feed scan zone (Fig. 1A, 1 10) of the scan glass substrate (108). The scanning interface device (102) also includes the bezel (228) that is disposed around a perimeter of the scan glass substrate (108) and holds the scan glass substrate (108) in place. The bezel (228) also includes the media ramp (120).

[00038] In some examples, the scanning interface device (102) also includes a calibration strip (330) that is laminated between the scan glass substrate (108) and the cover glass substrate (122). The calibration strip (330) is used to ensure consistent and high quality digital images of the media. For example, different scanners (104), or the same scanner at different points in time, may scan media differently. In other words, a scanner response may differ between scan jobs. The calibration strip (330) can be used to account for these variations to ensure a high quality digital image is produced. The calibration strip (330) can be a uniformly colored white strip that has a predetermined reflectance and is viewable by the scanner (104). During calibration, the scanner (104) captures an image of the calibration strip (330) and uses the image of the calibration strip (330) to compensate for variations in the scanner (104) response. This may occur at a point in time distinct from scanning. For example, calibration may occur periodically between scan jobs, on power up, or before each scan job.

[00039] If the calibration strip (330) becomes damaged or dirty, the images of the damaged or dirty area may cause the calibration routine to fail and can cause streaks or defects when scanning media or other objects. Accordingly, the cover glass substrate (122) is disposed over the calibration strip (330) such that the calibration strip (330) is laminated, and sealed, between the scan glass substrate (108) and the cover glass substrate (122) so as to prevent

contamination of the calibration strip (330).

[00040] As can be seen in Fig. 3, in some examples, the calibration strip (330) includes a slot (332) through which the scanner (Fig. 1A, 104) captures a digital image of the media. Accordingly, as can be seen in Fig. 4 below, the scanner (Fig. 1A, 104) may move from one position during calibration wherein the scanner (Fig. 1A, 104) is positioned to capture a surface of the calibration strip (330), to another position during scanning wherein the scanner (Fig. 1 A, 104) is aligned with the slot (332) so as to capture the bypassing media. [00041 ] As described above, the scanning interface device (102) also includes a media transition (Fig. 1 B, 134) between the sheet feed scan zone (Fig, 1A, 1 10) and the output media ramp (120). As depicted in Fig. 4, this media transition (Fig. 1 B, 134), in some examples may be a part of the calibration strip (330).

[00042] That is, Fig. 4 is a cross-sectional diagram of a portion of the scanning system (228) with a scanning interface device (Fig. 1A, 102) with dual- layer glass substrates, according to an example of the principles described herein. Specifically, Fig, 4 depicts the scan glass substrate (108), the cover glass substrate (122), the calibration strip (330) with the slot (332) and the media ramp (120) of the scanning interface device (Fig. 1A, 102). Fig. 4 also depicts the media transition (134) that smoothly guides the media along the media path (1 18) over the sheet feed scan zone (Fig, 1A, 1 10).

[00043] As depicted in Fig. 4, in some examples, the media transition (134) is formed from a portion of the calibration strip (330). in this example, a portion of the calibration strip (330) overlaps a leading edge of the media ramp (120). Using a portion of the calibration strip (330) to form the media transition (134) simplifies manufacturing, in other examples, the media transition (134) is formed of a component that is distinct from the calibration strip (330), For example, it may be desirable for the media transition (134) to have different properties than the calibration strip (330).

[00044] Fig. 4 also depicts an example where the scanning interface device (Fig. 1A, 102) does not include a polymer media guide. For example, as described above, in some cases where a single glass substrate is used, a polymer cover, as opposed to a glass cover, can be implemented. However, such polymer covers are fragile and prone to failure, marring, or inadvertent removal by a customer. By having a scanning interface device (Fig. 1 A, 102) that uses a glass cover as opposed to a polymer cover, greater life, greater strength, and less likelihood for inadvertent removal is obtained.

[00045] Figure 4 also depicts a system (228) wherein duplex scanning is performed. For example, as has been described, the system (226) includes at least one scanner (104) that can move and performs scanning of a surface of media thai faces the first scanner (104). The system (228) may also include a second scanner (436) that is disposed on an opposite side of the scanning interface device (Fig. 1A, 102) and faces an opposite direction as the first scanner (104) so as to capture a digital image of the opposite surface of the media. Being able to scan both surfaces of a document via one media pass is referred to as duplex scanning.

[00046] Note that in this example both scanners (104, 436) can be calibrated using the single calibration strip (330). That is, the first scanner (104) scans one surface of the calibration strip (330) through the scan glass substrate (108) and the second scanner (436) scans the opposite surface of the calibration strip (330) through the cover glass substrate (122).

[00047] To facilitate calibration of the second scanner (436), the cover glass substrate (122) may be less than or equal 0.4 millimeters thick. Using such a thin cover glass substrate (122) allows the calibration strip (330) to remain in focus during calibration.

[00048] Fig. 5 is a cross-sectional view of a scanning system (226) with a scanning interface device (Fig. 1A, 102) with dual-layer glass substrates, according to an example of the principles described herein, in some examples, the scan glass substrate (108) includes a recess (538) on a surface of the scan glass substrate (108) on the same side as the scanner (104). The recess (538) allows for adjusting of the focal point of the scanner (104) when scanning in the sheet feed scan zone (Fig. 1A, 1 10). In other words, the scanner (104) in the sheet feed scan zone is disposed closer to the scan glass substrate (108) as opposed to when the scanner (104) is in the flatbed scan zone. The amount of the focal shift may correspond to the increased optical thickness due to the thickness of the calibration strip (330) and the cover glass substrate (122) which are related to the index of refraction of the different materials present in the scan glass substrate (108), the slot (332), and the cover glass substrate (122).

[00049] For example, when using some types of scanners (104) such as contact image scanners that have a short focal length, the increased thickness resulting from the calibration strip (108) and the cover glass substrate (330) can impact the quality of image scanning, such as by causing the optics to be out of focus relative to the media. Accordingly, to allow such short-focal length scanners (104) to produce high quality images, the recesses (538) may offset the thickness of both the calibration strip (330) and the cover glass substrate (122) as well as accommodating for any transitions in the index of refraction along the path between the scanner (104) and the media,

[00050] As a specific example, when scanning in a flatbed mode the scanner (104-2) may have a focal length, equal to the distance, di, between the media path (1 18-2) and the scanner (104-2) and the scanner (104-2) may be a distance, cfe, away from the bottom surface of the scan glass substrate (108). In this example, the wheels (540-2) are against an underside surface of the scan glass substrate (108). Note that instances of components in the flatbed scan mode are identified by the reference indicator "*-2" whereas components in the sheet feed scan mode are identified by the reference indicator Were there to be no recess (538) to move the scanner (104-1 ) in a sheet feed scan mode closer to the media path (1 18-1 ), the additional thickness of the calibration strip (330) and the cover glass substrate (122) would increase the distance between the scanner (104-1 ) and the media, where such an increase in distance may be outside of the focal range of the scanner (104-1 ). Accordingly, the wheels (540- 1 ) enter the recess (538) and allow for the focal length of the scanner (104-1 ), to match the distance between the media path (1 18-1 ) and the scanner (104-1 ), 3. Note that in this example, the scanner (104-1 ) in the sheet feed scan mode is a distance, A, away from the underside of the scan glass substrate, which distance e?4 is less than the distance di.

[00051 ] To move the scanner (104) and consequently adjust the focal point of the scanner (104), wheels (540) on the scanner may rest on, and be biased against, an underside of the scan glass substrate (108). When the wheels (540-1 ) come into contact with the recesses (538), the entire scanner (104) shifts closer to the underside of the scan glass substrate (108) thus also shifting the focal length of the scanner (104) to match the distance between the media path (1 18-1 ) and the scanner (104-1 ). in another example, spacers may be provided on an underside of the scan glass substrate (108) in the flatbed scan zone such that the scanner (104) could nominally be located closer to the scan glass substrate (108) and the wheels (540) could transition onto the spacer when scanning in the flatbed scan location (104-2). The thickness of the spacer would be equivalent to the difference between efe and di.

[000S2] In one example, using such a glass laminated scan interface device 1 ) provides a robust scanning interface that doesn't excessively deflect under applied loads; 2) alleviates a difficult to seal glass to media ramp joint; 3) enhances image quality by alleviating the scanning of media through a transparent polymer media guide; 4) enhances the life of the scanning interface and corresponding scanning system as all optical surfaces are glass that do not degrade as quickly as other materials like polymer; 5) allows for a reduction of the size of the overall scanning system; 6) creates a smoother media transition from the sheet feed scan zone towards the output tray; and 7) allows for larger glass platens to be used for a given glass thickness by providing support around the entire perimeter of the platen. However, it is contemplated that the devices disclosed herein may address other matters and deficiencies in a number of technical areas.

[00053] The preceding description has been presented to illustrate and describe examples of the principles described. This description is not intended to be exhaustive or to limit these principles to any precise form disclosed. Many modifications and variations are possible in light of the above teaching.