Background matrix patterned display cover glass for color matching of multiple displays

Abstract

A display cover glass for multiple display units includes an A and B surface. The B surface has a first visual area, a first BM area surrounding the first visual area, a second visual area, a second BM area surrounding the second visual area, and a transition region between the first and second BM areas. The first BM area has a first ink on the B surface, and the second BM area has a second ink on the B surface, where the second ink color is different from a first ink color. The transition region includes the first and second inks on the B surface and has a gradient in a color density distribution of the first ink, the second ink, or both between the first BM area and the second BM area. The display cover glass provides a black front effect when the displays are turned off.

Description

Attorney Docket No. SP25-139PCTBACKGROUND MATRIX PATTERNED DISPLAY COVER GLASS FOR COLOR MATCHING OF MULTIPLE DISPLAYS CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of priority under 35 U.S.C. § 119 of Chinese Patent Application No. 202511147261.0 filed August 15, 2025, and also claims the benefit of priority under 35 U.S.C. § 119 of Chinese Patent Application No. 202510017828.6 filed January 6, 2025, the content of each of which is incorporated herein by reference in its entirety.TECHNICAL FIELD

[0002] Principles and embodiments of the present disclosure relate generally to display cover glass for display assemblies, in particular, display cover glass for display assemblies having multiple display units and methods of making the display cover glass.BACKGROUND

[0003] Vehicle manufacturers are creating interiors that better connect, protect and safely inform today's drivers and passengers. As the industry moves towards autonomous driving, a need exists for creating large format, appealing displays. There is already a trend towards larger displays including touch functionality in the new models from several OEMs. In many cases, the larger displays include a plurality of displays. For design reasons, often these multiple displays are attached to a single large display cover glass, which can span over half of the width of the vehicle console. When two different types of displays are attached to a single large display cover glass in a vehicle, issues can arise with color matching of the entire cover glass area with an ink in the non-display areas, which are called black matrix areas and surround the visual areas through which the images from the display units are projected. If the reflection colors of the display units are slightly different, achieving optimal color matching of the black matrix areas to the reflected colors of the display units with a single ink for all displays can be challenging.

[0004] Therefore, a continuing need exists for methods of manufacturing display cover glass having better color matching to account for different types of displays.SUMMARYAttorney Docket No. SP25-139PCT

[0005] The present disclosure is directed to display cover glass having improved color matching of black matrix areas for different types of display units and methods for making the display cover glass. According to a first aspect of the present disclosure a display cover glass for multiple displays may comprise an A surface and a B surface opposite the A surface, wherein the B surface may comprise a first visual area, a first black matrix (BM) area surrounding the first visual area, a second visual area, a second BM area surrounding the second visual area, and a transition region disposed between the first BM area and the second BM area. The first BM area may have a first ink applied to the B surface of the display cover glass, and the second BM area may have a second ink applied to the B surface of the display cover glass, wherein the second ink may have color different from a color of the first ink. The transition region may comprise the first ink and the second ink applied to the B surface, and the transition region may have a gradient in a color density distribution of the first ink, the second ink, or both between the first BM area and the second BM area.

[0006] A second aspect disclosed herein may include the first aspect, wherein the first ink and the second ink may both be opaque.

[0007] A third aspect disclosed herein may include either one of the first or second aspects, wherein a spatial density distribution of the first ink, the second ink, or both in the transition region may vary with position within the transition region, wherein the spatial density distribution is defined as a coverage area of an ink per unit area of the B surface of the display cover glass.

[0008] A fourth aspect disclosed herein may include the third aspect, wherein, in the transition region, the first ink, the second ink, or both may be applied in a halftone pattern comprising a plurality of dots, wherein a size of the plurality of dots, a center-to-center spacing of the plurality of dots, or both may vary with position within the transition region to achieve the spatial density distribution.

[0009] A fifth aspect disclosed herein may include any one of the first through fourth aspects, wherein, in the transition region, the first ink, the second ink, or both may be applied in a halftone pattern comprising a plurality of dots spaced apart from one another.Attorney Docket No. SP25-139PCT

[0010] A sixth aspect disclosed herein may include the fifth aspect, wherein, in the transition region, the first ink may be applied in a halftone pattern comprising a plurality of dots spaced apart from one another and the second ink may be applied as a solid pattern.

[0011] A seventh aspect disclosed herein may include the sixth aspect, wherein the second ink may be applied on top of the first ink in the transition region.

[0012] A eighth aspect disclosed herein may include any one of the fifth through seventh aspects, wherein a size of the plurality of dots, a center-to-center spacing of the plurality of dots, or both may vary with position within the transition region between the first BM area and the second BM area to produce the color density distribution of the first ink, the second ink, or both in the transition region.

[0013] A ninth aspect disclosed herein may include the eighth aspect, wherein the plurality of dots may have a size that is fixed and constant and the center-to-center spacing between each of the plurality of dots may change based on position of each of the plurality of dots in the transition region.

[0014] A tenth aspect disclosed herein may include the ninth aspect, wherein the first ink may be applied in the halftone pattern in the transition region, and the center-to-center spacing between each of the plurality of dots of the first ink may have a minimum value at a first end of the transition region and a maximum value at a second end of the transition region, where the first end of the transition region borders the first BM area and the second end of the transition region borders the second BM area.

[0015] An eleventh aspect disclosed herein may include the eighth aspect, wherein the center-to-center spacing of the plurality of dots may be fixed and the size of each of the plurality of dots may change based on position of the each of the plurality of dots in the transition region.

[0016] A twelfth aspect disclosed herein may include the eleventh aspect, wherein the first ink may be applied in the halftone pattern in the transition region, and the size of the plurality of dots of the first ink may have a maximum value at a first end of the transition region and a minimum value at a second end of the transition region, where the first end of the transition region borders the first BM area and the second end of the transition region borders the second BM area.Attorney Docket No. SP25-139PCT

[0017] A thirteenth aspect disclosed herein may include any one of the first through twelfth aspects, wherein the display cover glass may have a gradual color transition between the first BM area and the second BM area.

[0018] A fourteenth aspect disclosed herein may include any one of the first through thirteenth aspects, wherein the display cover glass may have no step change in color between the first BM area and the second BM area that is identifiable with the human eye.

[0019] A fifteenth aspect disclosed herein may include any one of the first through fourteenth aspects, wherein the first ink may have a first L* value, a first a* value, and a first b* value; the second ink may have a second L* value, a second a* value, and a second b* value; and the first L* value may be different from the second L*value, the first a* value may be different from the second a* value, the first b* value may be different from the second b* value, or combinations of these; and wherein L*, a*, and b* values are determined using a CM-700d handheld spectrophotometer from Konica Minolta.

[0020] A sixteenth aspect disclosed herein may include any one of the first through fifteenth aspects, wherein the display cover glass does not have any inks applied in the first visual area and the second visual area.

[0021] A seventeenth aspect disclosed herein may include any one of the first through sixteenth aspects, further comprising a semi-transparent antireflective (STAR) coating applied to an A surface of the display cover glass, the STAR coating having a transmittance (Tx) of greater than or equal to 60%.

[0022] An eighteenth aspect disclosed herein may include any one of the first through seventeenth aspects, further comprising a third visual area and a third BM area surrounding the third BM area, wherein the third BM area may comprise a third ink applied to the B surface of the display cover glass and the third ink may be different from the first ink, the second ink, or both.

[0023] A nineteenth aspect disclosed herein may include the eighteenth aspect, wherein the third BM area may be adjacent to the second BM area; the display cover glass may comprise a supplemental transition region disposed between the second BM area and the third BM area; the supplemental transition region may comprise the second ink and the third ink applied to theAttorney Docket No. SP25-139PCTB surface; and the supplemental transition region may have a gradient in the density distribution of the second ink, the third ink, or both between the second BM area and the third BM area.

[0024] A twentieth aspect disclosed herein may include the eighteenth aspect, wherein the third BM area may be adjacent to the first BM area; the display cover glass may comprise a supplemental transition region disposed between the first BM area and the third BM area; the supplemental transition region may comprise the first ink and the third ink applied to the B surface; and the supplemental transition region may have a gradient in the density distribution of the first ink, the third ink, or both between the first BM area and the third BM area.

[0025] A twenty-first aspect disclosed herein may include any one of the first through twentieth aspect and may be directed to a display assembly comprising the display cover glass of any one of the first through twentieth aspects, a first display unit bonded directly to the B surface of the display cover glass in the first visual area, and a second display unit bonded directly to the B surface of the display cover glass in the second visual area.

[0026] A twenty-second aspect disclosed herein may include the twenty-first aspect, wherein: the first BM area may be associated with the first display unit and the second BM area may be associated with the second display unit, which may have a reflected color different from the first display unit when both display units are turned off; the color of the first ink may match the reflected color of the first display unit when the first display unit is turned off; and the color of the second ink may match the reflected color of the second display unit when the second display unit is turned off.

[0027] A twenty -third aspect disclosed herein may include either one of the twenty-first or twenty-second aspects, wherein the display assembly does not have a gap between the B surface of the display cover glass and the first display unit, between the B surface of the display cover glass and the second display unit, or both.

[0028] A twenty-fourth aspect disclosed herein may include any one of the twenty-first through twenty-third aspects, wherein the first BM area may overlap the first display unit around the edges of the first visual area, and the second BM area may overlap the second display unit around the edges of the second visual area.

[0029] A twenty-fifth aspect disclosed herein may include any one of the twenty-first through twenty-fourth aspects, further comprising a third display unit and the display cover glass may comprise a third visual area, a third BM area, and a supplemental transition regionAttorney Docket No. SP25-139PCTbetween the third BM area and the first BM area or between the third BM area and the second BM area.

[0030] A twenty-sixth aspect disclosed herein may include any one of the twenty-first through twenty-fifth aspects, wherein, when the first display unit, the second display unit, or both are powered on, the first display unit, the second display unit, or both may have a brightness of from about 500 candelas / m2to about 2,500 candelas / m2, or from about 1,000 candelas / m2to about 2,000 candelas / m2.

[0031] A twenty-seventh aspect disclosed herein may be directed to a method of making a display cover glass, where the method may comprise: providing a cover glass having an A surface and a B surface; applying a first ink to a first black matrix (BM) area of the cover glass, wherein the first BM area may surround a first visual area; applying a second ink to a second BM area of the cover glass, wherein the second BM area may surround a second visual area, wherein the second ink may have a color different from a color of the first ink; and applying the first ink and the second ink to the cover glass in a transition region disposed between the first BM area and the second BM area to produce the display cover glass, wherein the transition region may have a gradient in a color density distribution of the first ink, the second ink, or both between the first BM area and the second BM area.

[0032] A twenty-eighth aspect disclosed herein may include the twenty-seventh aspect, further comprising varying a spatial density distribution of the first ink, the second ink, or both in the transition region, wherein the spatial density distribution is defined as a coverage area of an ink per unit area of the B surface of the display cover glass.

[0033] A twenty-ninth aspect disclosed herein may include the twenty-eighth aspect, wherein varying the spatial density distribution of the first ink, the second ink, or both in the transition region may comprise applying the first ink, the second ink, or both in a halftone pattern comprising a plurality of dots and varying a size of the plurality of dots, a center-to-center spacing of the plurality of dots, or both based on position of each of the plurality of dots within the transition region.

[0034] A thirtieth aspect disclosed herein may include the twenty-seventh aspect, wherein applying the first ink and the second ink to the cover glass in the transition region may compriseAttorney Docket No. SP25-139PCTapplying the first ink, the second ink, or both in a halftone pattern in the transition region, wherein the halftone pattern may comprise a plurality of dots spaced apart from one another.

[0035] A thirty-first aspect disclosed herein may include the thirtieth aspect, comprising applying the first ink in a halftone pattern in the transition region, wherein the halftone pattern of the first ink may comprise the plurality of dots spaced apart from one another, and applying the second ink in a solid pattern in the transition region.

[0036] A thirty-second aspect disclosed herein may include the thirty-first aspect, comprising applying the second ink on top of the halftone pattern of the first ink in the transition region.

[0037] A thirty-third aspect disclosed herein may include either one of the thirtieth or thirty-first aspects, further comprising varying a size of the plurality of dots, a center-to-center spacing of the plurality of dots, or both of the halftone pattern based on position within the transition region between the first BM area and the second BM area to produce the color density distribution of the first ink, the second ink, or both in the transition region.

[0038] A thirty-fourth aspect disclosed herein may include the thirty-third aspect, comprising maintaining the size of the plurality of dots of the halftone pattern constant and varying the center-to-center spacing between each of the plurality of dots in the halftone pattern based on the position of each of the plurality of dots in the transition region.

[0039] A thirty-fifth aspect disclosed herein may include the thirty-fourth aspect, comprising applying the first ink in the halftone pattern in the transition region, and varying the center-to-center spacing between each of the plurality of dots of the first ink from a minimum value at a first end of the transition region to a maximum value at a second end of the transition region, where the first end of the transition region borders the first BM area and the second end of the transition region borders the second BM area.

[0040] A thirty-sixth aspect disclosed herein may include the thirty-third aspect, comprising maintaining the center-to-center spacing of the plurality of dots constant in the transition region and varying the size of each of the plurality of dots based on a position of each of the plurality of dots in the transition region.

[0041] A thirty-seventh aspect disclosed herein may include the thirty-sixth aspect, comprising applying the first ink in the halftone pattern in the transition region, and varying the size of the plurality of dots of the first ink in the transition region from a maximum valueAttorney Docket No. SP25-139PCTat a first end of the transition region to a minimum value at a second end of the transition region, where the first end of the transition region borders the first BM area and the second end of the transition region borders the second BM area.

[0042] A thirty-eighth aspect disclosed herein may include any one of the twenty-seventh through thirty-seventh aspects, comprising: printing a first pattern of the first ink on a B surface of the display cover glass, wherein the first pattern may include a first solid pattern in the first BM area and a halftone pattern in the transition region; after printing the first pattern of the first ink, printing a second pattern of the second ink onto the B surface of the display cover glass, wherein the second pattern may include a second solid pattern covering the second BM area and the transition region; wherein: in the transition region, the second pattern of the second ink may overlap the halftone pattern of the first ink; and the overlap of the second pattern of the second ink on top of the halftone pattern of the first ink in the transition region may provide a gradient in color between the first ink in the first BM area and the second ink in the second BM area.

[0043] A thirty-ninth aspect disclosed herein may include any one of the twenty-seventh through thirty-seventh aspects, comprising: printing a first pattern of the first ink on a B surface of the display cover glass, wherein the first pattern may have a first solid pattern in the first BM area and a first halftone pattern in the transition region; after printing the first pattern of the first ink, printing a second pattern of the second ink onto the B surface of the display cover glass, where the second pattern may include a second solid pattern in the second BM area and a second halftone pattern in the transition region, wherein: in the transition region, the second halftone pattern of the second ink may overlap the first halftone area of the first ink; and the overlap of the second halftone pattern of the second ink on top of the first halftone pattern of the first ink in the transition region may provide a gradient in color between the first ink in the first BM area and the second ink in the second BM area.

[0044] A fortieth aspect disclosed herein may include any one of the twenty-seventh through thirty-ninth aspects, wherein the first ink and the second ink may both be opaque.

[0045] A forty-first aspect disclosed herein may include any one of the twenty-seventh through fortieth aspects, wherein the display cover glass may have a gradual color transition between the first BM area and the second BM area.Attorney Docket No. SP25-139PCT

[0046] A forty-second aspect disclosed herein may include any one of the twenty-seventh through forty-first aspects, wherein the display cover glass may have no step change in color between the first BM area and the second BM area that is identifiable with the human eye.

[0047] A forty-third aspect disclosed herein may include any one of the twenty-seventh through forty-second aspects, wherein the first ink may have a first L* value, a first a* value, and a first b* value; the second ink may have a second L* value, a second a* value, and a second b* value; and the first L* value may be different from the second L*value, the first a* value may be different from the second a* value, the first b* value may be different from the second b* value, or combinations of these; and wherein L*, a*, and b* values are determined using a CM-700d handheld spectrophotometer from Konica Minolta.

[0048] A forty-fourth aspect disclosed herein may include any one of the twenty-seventh through forty-third aspects, wherein the method does not include applying inks in the first visual area or the second visual area.

[0049] A forty-fifth aspect disclosed herein may include any one of the twenty-seventh through forty-fourth aspects, further comprising applying a third ink to a third BM area of the cover glass, wherein the third BM area may surround a third visual area, wherein the third ink may have a color different from the color of the first ink, the color of the second ink, or both.

[0050] A forty-sixth aspect disclosed herein may include the forty-fifth aspect, wherein the third BM area may be adjacent to the second BM area and the method further may comprise applying the second ink and the third ink to the cover glass in a supplemental transition region disposed between the second BM area and the third BM area, wherein the supplemental transition region may have a gradient in a color density distribution of the second ink, the third ink, or both between the second BM area and the third BM area.

[0051] A forty-seventh aspect disclosed herein may include the forty-fifth aspect, wherein the third BM area may be adjacent to the first BM area and the method further may comprise applying the first ink and the third ink to the cover glass in a supplemental transition region disposed between the first BM area and the third BM area, wherein the supplemental transition region may have a gradient in a color density distribution of the first ink, the third ink, or both between the first BM area and the third BM area.

[0052] A forty-eighth aspect disclosed herein may include any one of the twenty-seventh through forty-seventh aspects, further comprising applying a semi-transparent antireflectiveAttorney Docket No. SP25-139PCT(STAR) coating to an A surface of the display cover glass, the STAR coating having a transmittance (Tx) of greater than or equal to 60%.

[0053] A forty-ninth aspect disclosed herein may include any one of the twenty-seventh through forty-eighth aspects, and may be directed to a method of making a display assembly, the method comprising: preparing a display cover glass according to the method of any one of the twenty-seventh through forty-eighth aspects; coupling a first display unit to the B surface of the display cover glass in the first visual area; and coupling a second display unit to the B surface of the display cover glass in the second visual area.

[0054] A fiftieth aspect disclosed herein may include the forty-ninth aspect, comprising bonding the first display unit directly to the B surface of the display cover glass in the first visual area, and bonding the second display unit bonded directly to the B surface of the display cover glass in the second visual area.

[0055] A fifty-first aspect disclosed herein may include either one of the forty-ninth or fiftieth aspects, wherein the display cover glass may have a third visual area and a third BM region, and the method further may comprise coupling a third display unit directly to the B surface of the display cover glass in the third visual area.

[0056] A fifty-second aspect disclosed herein may be directed to a display assembly comprising: a display cover glass having an A surface and a B surface and having at least a first visual area, a second visual area, and a black matrix (BM) area surrounding the first visual area and the second visual area, wherein the BM area may comprise an ink applied to the B surface of the display cover glass; a first display unit coupled to the B surface of the display cover glass in the first visual area; and a second display unit coupled to the B surface of the display cover glass in the second visual area; wherein: when the first display unit is turned off, the first display unit may reflect a first color; when the second display unit is turned off, the second display unit may reflect a second color different from the first color; the ink may reflect an ink color in between the first color and the second color; and the display cover glass may comprise a semi-transparent antireflective (STAR) coating applied to the A surface of the display cover glass in the first visual area, the second visual area, and the BM area.

[0057] A fifty-third aspect disclosed herein may include the fifty-second aspect, wherein the first color of the first display unit may have a first L*, a first a*, and a first b*; the secondAttorney Docket No. SP25-139PCTcolor of the second display unit may have a second L*, a second a*, and a second b*; and the ink color may have an ink L*, an ink a*, and an ink b*; wherein: the first L* may be different from the second L*, the first a* may be different from the second a*, the first b* may be different from the second b*, or combinations thereof; and the ink L* may be a median value between the first L* and the second L*, the ink a* may be a median value between the first a* and the second a*, the ink b* may be a median between the first b* and the second b*, or any combinations thereof.

[0058] A fifty-fourth aspect disclosed herein may include either one of the fifty-second or fifty -third aspects, wherein the STAR coating may have a transmittance (Tx) of greater than or equal to 60%.

[0059] A fifty-fifth aspect disclosed herein may include any one of the fifty-second through fifty-fourth aspects, wherein: the display cover glass may have a third visual area and the display assembly may comprise a third display unit coupled to the B surface of the display cover glass in the third visual area; when the third display unit is turned off, the third display unit may reflect a third color different from the first color, the second color, or both, the third color having a third L*, a third a*, and a third b*; and the ink color may satisfy one or more of the following: the ink L* may be an average of the first L*, the second L*, and the third L*; the ink a* may be an average of the first a*, the second a*, and the third a*; the ink b* may be an average of the first b*, the second b*, and the third b*; or any combinations thereof.

[0060] A fifty-sixth aspect disclosed herein may be directed to a method of making a display cover glass, the method comprising: determining a first L* value, a first a* value, a first b* value, or combinations thereof for a first color of a first display unit, where the first color may be a color reflected when the first display unit is turned off; determining a second L* value, second a* value, a second b* value, or combinations thereof for a second display unit having a second color, where the second color may be a color reflected when the second display unit turned off and may be different from the first color of the first display unit; determining one or more of the following: a median L* value from the first L* value and the second L*value; a median a* value from the first a* value and the second a* value; a median b* value from the first b* value and the second b* value; or any combinations thereof. The method may further include formulating a single tunable ink having the median L* value, the median a* value, the median b* value, or any combinations thereof; applying the single tunable ink toAttorney Docket No. SP25-139PCTblack matrix (BM) areas of a B surface of the display cover glass; and applying a semitransparent antireflective (STAR) coating to an A surface of the display cover glass.

[0061] A fifty-seventh aspect disclosed herein may include the fifty-sixth aspect, wherein the STAR coating may have a transmittance (Tx) of greater than or equal to about 60%.

[0062] These and other aspects, advantages, and salient features will become apparent from the following detailed description, the accompanying drawings, and the appended claims.BRIEF DESCRIPTION OF THE DRAWINGS

[0063] FIG. 1 schematically depicts a B surface of a display cover glass having a plurality of visual areas for a plurality of different display units, where different regions of the display cover glass in FIG. 1 are shown with different cross-hatching patterns, according to embodiments shown and described herein;

[0064] FIG. 2 schematically depicts a cross-section of the display cover glass of FIG. 1 taken along reference line 2-2 in FIG. 1, according to embodiments shown and described herein;

[0065] FIG. 3 depicts a front view of a display assembly having the display cover glass of FIG. 1, a first display unit, and a second display unit, where the display assembly presents a black front effect when each of the first display unit and second display unit are turned off, according to embodiments shown and described herein;

[0066] FIG. 4 schematically depicts a perspective view of a display assembly for a vehicle, where the display assembly extends pillar-to-pillar and a single display cover glass and two different display units, according to embodiments shown and described herein;

[0067] FIG. 5 schematically depicts a cross-sectional view of the display assembly of FIG.1 taken along reference line 5-5 in FIG. 1, according to embodiments shown and described herein;

[0068] FIG. 6A schematically depicts a perspective view of a pillar-to-pillar vehicle display having multiple display units and a single display cover glass, where a color difference Delta E between a BM area of the display cover glass and a reflected color of the display units when the display units are off is great (the color difference Delta E is exaggerated for purposes of illustration), according to embodiments shown and described herein;Attorney Docket No. SP25-139PCT

[0069] FIG. 6B is a front view of the pillar-to-pillar vehicle display of FIG. 6A, according to embodiments shown and described herein;

[0070] FIG. 6C is a front magnified view of an outer surface of the display cover glass of the pillar-to-pillar vehicle display of FIG. 6A, according to embodiments shown and described herein;

[0071] FIG. 7A schematically depicts a perspective view of a pillar-to-pillar vehicle display having multiple display units and a single display cover glass, where a color difference Delta E between a BM area of the display cover glass and a reflected color of the display units is substantially smaller compared to the color difference in FIG. 6A, according to embodiments shown and described herein;

[0072] FIG. 7B is a front view of the pillar-to-pillar vehicle display of FIG. 7A, according to embodiments shown and described herein;

[0073] FIG. 7C is a front magnified view of an outer surface of the display cover glass of the pillar-to-pillar vehicle display of FIG. 7A, according to embodiments shown and described herein;

[0074] FIG. 8 schematically depicts a method for color matching a display cover glass to two different displays and creating a gradient in color density distribution in a transition region between a first black matrix area and a second black matrix area of the display cover glass, according to embodiments shown and described herein;

[0075] FIG. 9 schematically depicts two patterns of a halftone pattern of one of the inks in the transition region of FIG. 8, according to embodiments shown and described herein;

[0076] FIG. 10 schematically depicts various designs for a halftone pattern of one of the inks applied in the transition region of FIG. 8, according to embodiments shown and described herein;

[0077] FIG. 11 depicts a color chart for inkjet printing a color gradient in a transition region of a display cover glass, according to embodiments shown and described herein;

[0078] FIG. 12 schematically depicts a method of inkjet printing a color gradient in a transition region between a first BM area and a second BM area of the display cover glass of FIG. 2, according to embodiments shown and described herein;Attorney Docket No. SP25-139PCT

[0079] FIG. 13 schematically depicts a cross-sectional view of a display assembly having three display units coupled to the display cover glass, according to embodiments shown and described herein;

[0080] FIG. 14 graphically depicts Rx (left y-axis) and Tx (right y-axis) as a function of wavelength of light (x-axis) for a STAR coating, according to embodiments shown and described herein;

[0081] FIG. 15 graphically depicts an Rx color and a Tx color of a STAR coating relative to the b* value (x-axis) and a* value (y-axis) of the colors, according to embodiments shown and described herein;

[0082] FIG. 16 is a front view of a display cover glass having a single tunable ink in the BM areas and a STAR coating, where the different regions of the display cover glass are depicted with different cross-hatching patterns, according to embodiments shown and described herein;

[0083] FIG. 17 schematically depicts a cross-sectional view of a display assembly having two different display panels and the display cover glass of FIG. 16, where the cross-section is taken along the reference line 17-17 in FIG. 16, according to embodiments shown and described herein;

[0084] FIG. 18 schematically depicts a tunable ink system comprising a first ink and a second ink that are blended to produce a single tunable ink having a desired color, according to embodiments shown and described herein;

[0085] FIG. 19 graphically depicts an SCI L* value (y-axis) as a function of ratio of first ink to second ink (x-axis) in the single tunable ink of FIG. 18, according to embodiments shown and described herein;

[0086] FIG. 20 graphically depicts an SCE L* value (y-axis) as a function of ratio of first ink to second ink (x-axis) in the single tunable ink of FIG. 18, according to embodiments shown and described herein;

[0087] FIG. 21 is a photograph showing an actual color appearance between a first visual area (VA) and a BM area (BM) of a display assembly having a display cover glass with a single tunable ink in the BM areas and a STAR coating, where the first visual area is associated withAttorney Docket No. SP25-139PCTa first display unit having a reflected color, according to embodiments shown and described herein; and

[0088] FIG. 22 is a photograph showing an actual color appearance between a second visual area (VA) and the BM area (BM) of the display assembly of FIG. 21 having a display cover glass with a single tunable ink in the BM areas and a STAR coating, where the second visual area is associated with a second display unit having a reflected color different from the first display unit, according to embodiments shown and described herein.

[0089] As previously discussed, the subject matter disclosed herein is directed to display cover glass that shows no color differences between visual areas and black matrix areas when display units coupled to the display cover glass are turned off. For purposes of illustration, differences in color, patterns, dimensions, etc. in the drawings are greatly exaggerated for purposes of illustrating the subject matter disclosed herein. For instance, the color differences in FIGS. 6A, 6B, 6C, 7A, 7B, and 7C, for example, are exaggerated for purposes of illustration.DETAILED DESCRIPTION

[0090] Reference will now be made in detail to embodiments of a display cover glass for multiple displays and methods of making the display cover glass to improve color matching between the multiple visual areas and between the visual areas and the black matrix areas, examples of which are illustrated in the accompanying drawings. Display assemblies comprising the display cover glass are also disclosed. Referring now to FIGS. 1 and 2, one embodiment of a display cover glass 100 for multiple display units is schematically depicted. Referring to FIG. 2, the display cover glass 100 may comprise a cover glass 102, which may be a glass sheet having an A surface 104 and a B surface 106 opposite the A surface 104. Referring to FIGS. 1 and 2, the B surface 106 may comprise a first visual area 110, a second visual area 112, a first black matrix (BM) area 120 surrounding the first visual area 110, a second BM area 130 surrounding the second visual area 112, and a transition region 140 disposed between the first BM area 120 and the second BM area 130. The first BM area 120 may have a first ink 122 applied to the B surface 106 of the display cover glass 100, and the second BM area 130 may have a second ink 132 applied to the B surface 106 of the display cover glass 100. The second ink 132 may have a color different from a color of the first ink 122. Referring to FIG. 2, the transition region 140 may have both the first ink 122 and the second ink 132 applied to the B surface 106. The transition region 140 may have a gradient inAttorney Docket No. SP25-139PCTa color density distribution of the first ink 122, the second ink 132, or both between the first BM area 120 and the second BM area 130.

[0091] Methods of making the display cover glass 100 are also disclosed herein. Referring again to FIGS. 1 and 2, a method of making the display cover glass 100 may include providing the cover glass 102 having the A surface 104 and the B surface 106; applying the first ink 122 to the first BM area 120 of the cover glass 102, wherein the first BM area 120 surrounds the first visual area 110; applying the second ink 132 to the second BM area 130 of the cover glass 102, wherein the second BM area 130 surrounds the second visual area 112 and the second ink 132 has a color different from a color of the first ink 122; and applying the first ink 122 and the second ink 132 to the B surface 106 of the cover glass 102 in the transition region 140 disposed between the first BM area 120 and the second BM area 130 to produce the display cover glass 100. As previously discussed, the transition region 140 may have a gradient in a color density distribution of the first ink 122, the second ink 132, or both between the first BM area 120 and the second BM area 130.

[0092] Referring again to FIG. 2, display assemblies 10 may include the display cover glass 100 and a plurality of display units coupled to the B surface 106 of the display cover glass 100, such as the first display unit 12 and second display unit 14. Referring to FIG. 3, the display cover glass 100 may provide improved color matching such that the display cover glass 100 provides a dead front effect when the display units of the display assembly are turned off. The dead front effect refers to the A surface 104 appearing to the human eye as a single color with no distinguishable color differences between the first BM area, the second BM area, and the transition area or between the BM areas and the visual areas. FIG. 3 is intended to be depicted as a rectangle having a single color to illustrate the dead front effect achieved by the display cover glass disclosed herein.

[0093] In the following description, like reference characters designate like or corresponding parts throughout the several views shown in the figures. It is also understood that, unless otherwise specified, terms such as "top," "bottom," "outward," "inward," and the like are words of convenience and are not to be construed as limiting terms. In addition, whenever a group is described as comprising at least one of a group of elements and combinations thereof, it is understood that the group may comprise, consist essentially of, or consist of any number of those elements recited, either individually or in combination withAttorney Docket No. SP25-139PCTeach other. Similarly, whenever a group is described as consisting of at least one of a group of elements or combinations thereof, it is understood that the group may consist of any number of those elements recited, either individually or in combination with each other. Unless otherwise specified, a range of values, when recited, includes both the upper and lower limits of the range as well as any ranges therebetween. As used herein, the indefinite articles "a," "an," and the corresponding definite article "the" mean "at least one" or "one or more," unless otherwise specified.

[0094] As used herein, the term "visual area" (abbreviated VS) refers to a region of a display cover glass coupled to a display, in which region the images displayed by the display are visible through the display cover glass.

[0095] As used herein, the term "black matrix area" (abbreviated BM area) refers to a region of a display cover glass surrounding a visual area and having an ink that restricts passage of light through the display cover glass. The term "black matrix" is a term of art in the field of display cover glass and is not intended to restrict or limit the color of the ink in the black matrix area. The ink may have various shades of color depending on the color of the display unit when the display unit is turned off, such as but not limited to different shades of black, dark gray, blue, violet, green, red, other colors, or any combinations thereof.

[0096] As used herein, the term "dead front effect" refers to an appearance of the display cover glass when the display units are turned off and where an outer surface of the display cover glass appears as a single color with no color differences discernable to the human eye between the black matrix areas and the visual areas or between two different black matrix areas.

[0097] As used herein, the term "off state" or "off condition" or just "off1refers to a status of a display unit in which the display unit is not emitting light, such as but not limited a condition in which the power supply to the display unit is interrupted or ceased.

[0098] As used herein, the terms "visible light" and "visible spectrum" both refer to light having wavelength in a range of from about 380 nm to about 700 nm, which is the range of wavelengths of light that are generally visible to the average human eye.

[0099] As used herein, the term "Specular Component Included," which is abbreviated SCI, refers to color measurements in which both the specular component and diffuse light are included in the measurement, where the specular component is the light reflected directly back from a surface and the diffuse light is the scattered light reflected from the surface.Attorney Docket No. SP25-139PCT

[0100] As used herein, the term "Specular Component Excluded," which is abbreviated SCE, refers to color measurements in which only the diffuse light is included in the measurement, and the specular component is excluded.

[0101] Referring now to FIG. 4, a display assembly 10 having a plurality of display units and a single display cover glass for a vehicle interior is schematically depicted. As shown in FIG. 4, the display assembly 10 may be integrated into a console 20 of the vehicle. The display assembly 10 may extend across a majority of a length of the console 20, such as across a majority (greater than 50%) of a pillar-to-pillar distance of the vehicle. The display assembly 10 may have a display cover glass 100 and multiple display units, such as but not limited to a first display unit 12 and a second display unit 14, attached to the B surface of the display cover glass 100. The single display cover glass 100 may be the cover glass for each of the multiple display units.

[0102] Referring now to FIG. 5, the display assembly 10 of FIG. 1 is shown in a crosssection taken along reference line 5-5 in FIG. 2. As shown in FIG. 5, the display cover glass 100 comprises a cover glass 102 having an A surface 104 and a B surface 106. The cover glass 102 may be any type of glass suitable for use as a cover glass for electronics. One example of a glass suitable for use as the cover glass 102 may include but is not limited to GORILLA GLASS® from Corning Incorporated. Other types of cover glass are contemplated. However, it is understood that the subject matter disclosed herein is not intended to be limited by the type of glass used as the cover glass.

[0103] The display cover glass 100 further includes at least one visual area, such as visual area 110 shown in FIG. 5, and at least one black matrix area (BM area), such as the first BM area 120 shown in FIG. 5. A display unit, such as the first display unit 12 shown in FIG. 5, may be attached to the B surface 106 of the display cover glass 100. The display unit, such as first display unit 12, may be centered on the visual area. The display unit 12 may be attached to the B surface 106 of the display cover glass 100 with a transparent adhesive layer 30. The visual area, such as the first visual area 110 in FIG. 5, is the region of the display cover glass 100 that is transparent and allows the image produced by the display unit 12 to pass through the display cover glass 100 to be visible to the user from the A surface 104 of the display cover glass 100. The display cover glass 100 may have a plurality of visual areas, such as 2, 3, 4, or more than 4 visual areas, each of which may correspond to a display unit. The display assembly 10 mayAttorney Docket No. SP25-139PCTinclude a plurality of display units attached to the B surface 106 of the display cover glass 100, such as 2, 3, 4, or more than 4 display units.

[0104] Each visual area may be surrounded by a BM area, such as the first BM area 120 shown in FIG. 5. The BM area may have an ink, such as the first ink 122, applied to the B surface 106 of the cover glass 102. The ink (e.g., first ink 122) in the BM area (e.g., first BM area 120) may overlap with display unit 12 around the edges. The ink may be opaque so that the ink prevents passage of light through the display cover glass in the BM areas. Thus, the BM areas restrict the passage of light through the display cover glass to passage of light only through the visual areas of the display cover glass 100.

[0105] The ink in the BM areas may be formulated to have a color that matches the color reflected by the display unit when the display unit is turned off. For instance, referring again to FIG. 5, the color of the first ink 122 in the first BM area 120 may be matched to a color reflected by the first display unit 12 when the first display unit 12 is turned off. The ink in the BM area can be any color, such as but not limited to different shades of black, blue, violet, green, gray, red, other color, or combinations of colors, and it is understood that the ink is not intended to be limited to black inks or shades of black inks. The inks in the BM areas are color matched to the reflected color of one of the display units so that, when the display units are turned off, the entire display assembly appears as a single black panel component. This appearance of a single black panel component is referred to herein as a dead front effect.

[0106] The reflected color of each display unit can be quantified using L*, a*, and b* values, which can be determined using a spectrophotometer, such as a CM700D handheld spectrophotometer available from Konica Minolta. Color matching between the visual areas and the BM area of the display cover glass can be accomplished by formulating the ink for the BM area to have a color with L*, a*, and b* values similar to the L*, a*, and b* values of the reflected color of the display units in the off condition. The quality of the color matching can be quantified using the color difference Delta E, which is provided in Equation 1, (EQU. 1).In EQU. 1, L*, a*, b* represent brightness and color coordinates obtained using a spectrophotometer, as previously discussed herein.

[0107] The recent trend in vehicle displays is towards larger display cover glass designs servicing multiple display units. Referring now to FIGS. 6A-6C, for example, a pillar-to-pillarAttorney Docket No. SP25-139PCTdisplay assembly 10 in a vehicle can use a single horizontally long display cover glass 100 on the vehicle dashboard. Multiple display units can be attached to this display cover glass. In FIGS. 6A-6C, the two display units are the same type of display unit. When the display units are turned off, it is important for the design to create the perception of a single long black panel, which is known as a dead front effect. Referring to FIG. 6C, the display cover glass 100 is shown as having a large color difference AE between the visual area 110 and BM area 120. The color differences in FIGS. 6A-6C are exaggerated for purposes of illustration. When the color difference AE is greater than about 4, the color difference can be readily discerned by the human eye, which does not result in a dead front effect when the display units are turned off. Instead, both visual areas are clearly visible in contrast to the black matrix area.

[0108] Referring now to FIGS. 7A-7C, an example of a display cover glass 100 with improved color matching is depicted. The color difference is exaggerated for purposes of illustration and for reproducibility of the images. The display cover glass 100 in FIG. 7C has a AE between the visual areas 110 and the BM area 120 that is significantly less than the AE of the display cover glass of FIG. 6C. As a result, the difference in color between the visual area 110 and the BM area 120 for the display cover glass 100 of FIG. 7C is significantly less and the display cover glass provides an improved dead front effect compared to the display cover glass of FIG. 6C. Ideally, the AE between the visual areas 110 and the BM areas 120 should be a small as possible to provide improved color matching and dead front effect. An improved dead front effect can be achieved when the color difference AE is less than or equal to about 2.

[0109] It is relatively straightforward to color match the BM areas of the display cover glass to the color reflected from a single display or from multiple display units when the display units are of the same type and reflect the same color when turned off. However, when two or more different types of display units are attached to a single larger display cover glass, such as in a vehicle (e.g., car, truck, boat, airplane, etc.), manufacturers often experience issues with color matching of the entire BM area of the display cover glass in the non-display areas with the two or more different types of display units reflecting different colors. In cases where multiple display units of different types or produced by different manufacturers are attached to a large display cover glass, the reflective colors of the display units may be different. If the reflected colors of the display units are different, achieving optimal color matching with a single ink in the BM areas can be challenging for all of the multiple display units.Attorney Docket No. SP25-139PCT

[0110] Previous color matching solutions for multiple different display units focus on using a single ink for the BM areas, where the single ink has a color that is an average between the reflected colors of the two different display units (i.e., an average of the L*, a*, and b* values of the reflected colors of the two different displays). However, the differences between the reflected colors of the multiple display units or between the visual areas and the black matrix areas of the display cover glass can still be easily discernable to the consumer, which is undesirable.

[0111] In some other conventional methods for reducing color differences, a semitransparent antireflective (STAR) coating can be employed to try to mitigate color differences and improve color consistency, such as by masking or obscuring the color differences. Display cover glass with a STAR coating can visually hide the boundaries between the BM areas and visual areas of the display cover glass for producing dead-front effect as well as achieving color matching of display units used for multi-screen vehicle display. The mechanism underlying the method is to lower the transmittance of the display cover glass. At the reduced transmittance, average human perception cannot easily distinguish the color difference in low brightness circumstance. Color differences between the visual areas and BM areas can be calculated by EQU. 1. Normally, reducing the L* gap between the visual areas and BM areas or between different types of display units for multi-screen display assemblies by using a STAR coating with lower transmittance can reduce the AE, which means improvements in color-matching. However, to reduce color difference between different display panels and at the boundary of viewing areas and the BM areas, display cover glasses with only a STAR coating normally are required to reduce the transmittance of the glass to less than 40% or even less than or equal to 30% to improve the perceived color difference and mask the transition between the different colors. This reduction in the transmittance of the cover glass can result in significant brightness reduction for the display units, which is the side effect customers do not want to have.

[0112] The present application is directed to display cover glasses with improved color matching between different types of display units and between visual areas and black matrix areas (BM areas). The present application is also directed to methods for producing the display cover glass having the improved color matching. The display cover glasses disclosed herein include different inks that are color matched to each of the different display units and applied to each BM area surrounding each of the display units. The display cover glass further includes a transition region between each different pair of adjacent BM areas. In the transition region,Attorney Docket No. SP25-139PCTthe two different inks are applied to achieve a gradient in a color density distribution of one or both of the different inks, which provides a smooth color transition between each of the two different colored inks and a seamless visual boundary between the two BM areas. In other words, each visual area, such as a first visual area associated with a first display unit and a second visual area associated with a second display unit, is color matched with its own ink (i.e., first ink and second ink), and a smooth transition is made from the first ink to the second ink in the transition region. The result is a display cover glass for two or more different display units where the display cover glass has improved color matching and presents a dead front effect having a uniform color when all of the different display units are turned off. The plurality of different inks may be a number of different inks equal to the number of different display units to be attached to the display cover glass.

[0113] Referring again to FIGS. 1 and 2, one embodiment of the display cover glass 100 disclosed herein for multiple display units is schematically depicted. Referring to FIG. 2, as previously discussed, the display cover glass 100 has the A surface 104 and the B surface 106 opposite the A surface 104. Referring again to FIGS. 1 and 2, the B surface 106 may comprise at least a first visual area 110, a second visual area 112, a first BM area 120 surrounding the first visual area 110, a second BM area 130 surrounding the second visual area 114, and a transition region 140 disposed between the first BM area 120 and the second BM area 130. Referring to FIG. 2, the first visual area 110 may be associated with the first display unit 12, and the second visual area 112 may be associated with the second display unit 14. Although described in the context of a display cover glass 100 for two display units, it is understood that the display cover glass 100 could be configured similarly for three, four, or more than four display units by adding additional visual areas, BM areas, and additional transition regions to accommodate the additional display units. The first BM area 120 may have a first ink 122 applied to the B surface 106 of the display cover glass 100, and the second BM area 130 may have a second ink 132 applied to the B surface 106 of the display cover glass 100, wherein the second ink 132 may have a color different from a color of the first ink 122. The transition region 140 may comprise the first ink 122 and the second ink 132 applied to the B surface 106. The transition region 140 has a gradient in a color density distribution of the first ink 122, the second ink 132, or both between the first BM area 120 and the second BM area 130.Attorney Docket No. SP25-139PCT

[0114] The display cover glass 100 disclosed herein may be made by methods comprising providing a cover glass 102 having the A surface 104 and the B surface 106; applying the first ink 122 to the first BM area 120, wherein the first BM area 120 surrounds the first visual area 110; and applying the second ink 132 to the second BM area 130, wherein the second BM area 130 surrounds the second visual area 112 and the second ink 132 has a color different from a color of the first ink 122. The methods may further include applying the first ink 122 and the second ink 132 to the cover glass 102 in the transition region 140 disposed between the first BM area 120 and the second BM area 130 to produce the display cover glass 100, wherein the transition region 140 has a gradient in a color density distribution of the first ink 122, the second ink 132, or both between the first BM area 120 and the second BM area 130.

[0115] In embodiments, the methods may produce a display cover glass that still has a color difference or color transition that is perceptible by a human being. In these embodiments, the methods may include applying a STAR coating to the A surface 104 of the display cover glass, where the STAR coating has a high transmittance of greater than or equal to about 60%, which is significantly greater than the conventional STAR coatings having a transmittance of less than about 40% or even about 30%. The addition of the STAR coating having transmittance of greater than or equal to about 60% may further improve the color matching appearance of the display cover glass 100 to provide a dead front effect when the display units are turned off while also maintain the vehicle display at an appropriate brightness level when the display units are turned on.

[0116] Referring again to FIGS. 1 and 2, in embodiments, the methods for improving the color matching of the display cover glass 100 for multiple display units may include providing a cover glass 102, a first display unit 12, and a second display unit 14, where a reflected color of the first display unit 12 is different from a reflected color of the second display unit 14. The methods may further include applying the first ink 122 to the first BM area 120 surrounding the first visual area 110, which is associated with the first display unit 12. The method may further include applying a second ink 132 to the second BM area 130 surrounding the second visual area 112, which is associated with the second display unit 14. The method may further include applying the first ink 122 and the second ink 132 in the transition region 140 to produce a gradient in a color density distribution of the first ink 122, the second ink 132, or both between the first BM area 120 and the second BM area 130.Attorney Docket No. SP25-139PCT

[0117] In embodiments, the first display unit 12 may have a first reflected color when in an off condition, and the second display unit 14 may have a second reflected color when in an off condition. The first reflected color of the first display unit 12 in the off condition may be different from the second reflected color of the second display unit 14 in the off condition. For instance, the first reflected color may have an L* value, an a* value, and a b* value, and the second reflected color may have an L* value, an a* value, and a b* value. In embodiments, the L* value, the a* value, the b*value, or combinations thereof of the first reflected color of the first display unit 12 may be different from the L* value, the a* value, the b*value, or combinations thereof of the second reflected color of the second display unit 14. In other words, the first reflected color and the second reflected color may have different L* values, different a* values, different b* values, or any combination thereof. The first reflected color and the second reflected color can be any color, such as but not limited to various shades of black, gray, gray, blue, green, violet, red, other color, or different shades of colors.

[0118] Referring to FIGS. 1 and 2, the first ink 122 for the first BM area 120 and the second ink 132 for the second BM area 130 may both be opaque inks that prevent light from passing through the ink and through the display cover glass 100 in the first BM area 120, the second BM area 130, and the transition region 140. The first ink 122, the second ink 132, or both may have a transmittance of light in the visual spectrum (e.g., light having wavelength of from about 380 nm to about 700 nm) of less than about 10%, such as less than about 5%, or even less than about 1%.

[0119] The first ink 122 may be formulated to have a color similar to or the same as the first reflected color of the first display unit 12. The first ink 122, when cured / dried, may have a first L* value, a first a* value, and a first b* value, as determined using a spectrophotometer as previously discussed herein. The first ink 122 may be formulated so that the first L* value, first a* value, first b* value, or combinations thereof are the same as or similar to the L* value, the a* value, the b* value, or combinations thereof of the first reflected color of the first display unit 12. In embodiments, the AE between the first ink 122 and the first reflected color of the first display unit 12 may be less than or equal to about 2, such as less than or equal to about 1.8, less than or equal to about 1.6, less than or equal to about 1.4, less than or equal to about 1.2, less than or equal to about 1, less than or equal to about 0.8, less than or equal to about 0.6, less than or equal to about 0.5, from 0 to about 2, from 0 to about 1.8, from 0 to about 1.6, fromAttorney Docket No. SP25-139PCT0 to about 1.4, from 0 to about 1.2, from about 0 to about 1, or any range or subrange therebetween, where the AE is calculated according to the formula in EQU. 1.

[0120] The second ink 132 may be formulated to have a color similar to or the same as the second reflected color of the second display unit 14. The second ink 132, when cured / dried or otherwise in a solid state, may have a second L* value, a second a* value, and a second b* value, as determined using a spectrophotometer as previously discussed herein. The second ink 132 may be formulated so that the second L* value, second a* value, second b* value, or combinations thereof are the same as or similar to the L* value, the a* value, the b* value, or combinations thereof of the second reflected color of the second display unit 14. In embodiments, the AE between the second ink 132 and the second reflected color of the second display unit 14 may be less than or equal to about 2, such as less than or equal to about 1.8, less than or equal to about 1.6, less than or equal to about 1.4, less than or equal to about 1.2, less than or equal to about 1, less than or equal to about 0.8, less than or equal to about 0.6, less than or equal to about 0.5, from 0 to about 2, from 0 to about 1.8, from 0 to about 1.6, from 0 to about 1.4, from 0 to about 1.2, from about 0 to about 1, or any range or subrange therebetween, where the AE is calculated according to the formula in EQU. 1.

[0121] The first ink 122 may be a different color compared to the second ink 132. In embodiments, the first ink 122 may have a first L* value, a first a* value, and a first b* value; the second ink 132 may have a second L* value, a second a* value, and a second b* value; and the first L* value is different from the second L*value, the first a* value is different from the second a* value, the first b* value is different from the second b* value, or any combinations thereof; and wherein L*, a*, and b* values are determined using a CM-700d handheld spectrophotometer from Konica Minolta. In embodiments, the first L* value of the first ink 122 may be different from the second L* value of the second ink 132 by at least about 5%, at least about 10%, at least about 15%, or even at least about 20% of the second L* value. In embodiments, the first a* value of the first ink 122 may be different from the second a* value of the second ink 132 by at least about 5%, at least about 10%, at least about 15%, or even at least about 20% of the second a* value. In embodiments, the first b* value of the first ink 122 may be different from the second b* value of the second ink 132 by at least about 5%, at least about 10%, at least about 15%, or even at least about 20% of the second b* value. In embodiments, the difference in color AE between the color of the first ink 122 in the first BM area 120 and the color of the second ink 132 in the second BM area 130 area may be greaterAttorney Docket No. SP25-139PCTthan zero, such as greater than or equal to about 0.5, greater than or equal to about 1, greater than or equal to about 1.5, greater than or equal to about 2, from about 0.5 to about 10, from about 0.5 to about 5, from about 0.5 to about 4, from about 0.5 to about 3, from 1 to about 10, from about 1 to about 6, from about 1 to about 5, from about 1 to about 4, from about 1 to about 3, from about 1.5 to about 10, from about 1.5 to about 6, from about 1.5 to about 5, from about 1.5 to about 4, from about 1.5 to about 3, from about 2 to about 10, from about 2 to about 6, from about 2 to about 5, from about 2 to about 4, from about 2 to about 3, from about 2 to about 10, from about 3 to about 6, from about 3 to about 5, from about 3 to about 4, or any range or subrange therebetween, where the AE is calculated according to the formula in Equation 1.

[0122] Referring now to FIG. 8, the step of applying the first ink 122 and the second ink 132 to the B surface 106 of the cover glass 102 is schematically depicted. Applying first ink 122 and the second ink 132 to the B surface 106 may be accomplished using any suitable printing method, such as but not limited to ink jet printing, screen printing, doctor blade printing, spray printing, transfer printing, or other printing method. As shown in FIG. 8, the first ink 122 is applied to the first BM area 120 of the B surface 106 of the cover glass 102, where the first BM area 120 surrounds the first visual area 110 corresponding to the first display unit 12 (FIG. 2). The methods may include applying the first ink 122 in the first BM area 120 in a solid pattern that completely surrounds the first visual area 110. As shown in FIG. 8, the second ink 132 may be applied to the second BM area 130 of the B surface 106 of the cover glass 102, where the second BM area 130 surrounds the second visual area 112 corresponding to the second display unit 14 (FIG. 2). The methods may include applying the second ink 132 in the second BM area 130 in a solid pattern that completely surrounds the second visual area 112, wherein the color of the second ink 132 is different from the color of the first ink 122. The methods do not include applying any of the inks in the first visual area 110 or the second visual area 112.

[0123] Referring again to FIG. 8, as previously discussed, the methods disclosed herein may include applying the first ink 122 and the second ink 132 to the B surface 106 of the cover glass 102 in the transition region 140 disposed between the first BM area 120 and the second BM area 130 to produce the display cover glass 100. The methods may include applying the first ink 122 and the second ink 132 to the transition region 140 so that the transition region 140 has a gradient in a color density distribution of the first ink 122, the second ink 132, orAttorney Docket No. SP25-139PCTboth between the first BM area 120 and the second BM area 130. In other words, the first ink 122 and the second ink 132 may be applied to the transition region 140 in a manner that produces a gradient in color density distribution from the color of the first ink 122 in the first BM area 120 to the color of the second ink 132 in the second BM area 130. This produces a smooth color transition in the transition region 140 between the color of the first ink 122 in the first BM area 120 to the color of the second ink 132 in the second BM area 130.

[0124] Producing the gradient in the color density distribution in the transition region 140 may include varying a spatial density distribution of the first ink 122, the second ink 132, or both in the transition region 140. The spatial density distribution is defined as a coverage area of a particular ink (i.e., the first ink 122 or second ink 132) per unit area of the B surface 106 of the display cover glass 100. In embodiments, varying the spatial density distribution of the first ink 122, the second ink 132, or both in the transition region 140 may include applying the first ink 122, the second ink 132, or both in a halftone pattern 146 in the transition region 140, where the halftone pattern 146 may include a plurality of dots 150, which may have a size and a center-to-center spacing. The shape of the dots 150 is not particular limited. The dots 150 may have any suitable shape, such as but not limited to circular, oval, square, diamond, rectangular, triangular, polygonal, irregular shape, or combinations of shapes. Varying the spatial density distribution of the first ink 122, the second ink 132, or both in the transition region 140 may further include varying the size of the plurality of dots 150, the center-to-center spacing of the plurality of dots 150, or both based on the position of each of the plurality of dots 150 within the transition region 140. The halftone pattern 146 may be applied through spray printing, inkjet printing, screen printing, or other type of printing.

[0125] Referring now to FIG. 9, two different embodiments of the halftone pattern 146 (e.g., halftone pattern 146 A and halftone pattern 146B) in the transition region 140 are schematically depicted. In FIG. 9, the first ink 122 is printed in the halftone patterns 146A and 146B. In halftone pattern 146A in the top left of FIG. 9, the center-to-center distance 152 between the dots 150 in the halftone pattern 146A is maintained constant while the sizes of the dots 150 in the halftone pattern 146A are varied from one side of the transition region 140 to the other side. Since the ink in the halftone pattern 146A is the first ink 122, the size of the dots 150 are largest proximate the first BM area 120 and get smaller as the position of the dots 150 get closer to the second BM area 130.Attorney Docket No. SP25-139PCT

[0126] In the halftone pattern 146B on the top right of FIG. 9, the sizes of the dots 150 in the halftone pattern 146B are maintained constant while the center-to-center distance 152 between the dots 150 in the halftone pattern 146B is varied from one side of the transition region 140 to the other side, such as increasing in center-to-center distance from distance 152A proximate the first BM area to distance 152B in the middle of the transition region 140 to distance 152C proximate to the second BM area 130. In embodiments, both the size of the dots 150 and center-to-center spacing 152 of the dots 150 in the halftone pattern 146 can be varied from one side of the transition region 140 to the other side to produce the gradient in the spatial density distribution in the transition region 140. The design of the halftone pattern 146 can be made based on the changes in the area ratio of the halftone pattern. Referring now to FIG. 10, additional embodiments of the halftone patterns 146 in the transition region 140 between the first BM region 120 and the second BM region 130 are schematically depicted. Other configurations of the halftone pattern 146 are contemplated by varying the shape, size, and / or spacing of the dots 150 in the halftone pattern 146.

[0127] Referring again to FIG. 9, in embodiments, applying the first ink 122, the second ink 132, or both in the transition region 140 may include applying the first ink 122, the second ink 132, or both in a halftone pattern 146 in the transition region 140 and varying the size of the plurality of dots 150, a center-to-center spacing of the plurality of dots 150, or both of the halftone pattern 146 based on position within the transition region 140 between the first BM area 120 and the second BM area 130 to produce the color density distribution of the first ink 122, the second ink 132, or both in the transition region 140. In embodiments, applying the first ink 122, the second ink 132, or both in a halftone pattern 146 in the transition region 140 may include maintaining the size of the plurality of dots 150 of the halftone pattern 146 constant and varying the center-to-center spacing between each of the plurality of dots 150 in the halftone pattern 146 based on the position of each of the plurality of dots 150 in the transition region 140. In embodiments, applying the first ink 122, the second ink 132, or both in a halftone pattern 146 in the transition region 140 may include maintaining the center-to-center spacing between each of the plurality of dots 150 in the halftone pattern 146 constant and varying the size of the plurality of dots 150 of the halftone pattern 146 based on the position of each of the plurality of dots 150 in the transition region 140. In embodiments, applying the first ink 122, the second ink 132, or both in a halftone pattern 146 in the transition region 140 may includeAttorney Docket No. SP25-139PCTvarying the size and the center-to-center distance between the plurality of dots 150 of the halftone pattern 146 based on the position of each of the plurality of dots 150 in the transition region 140.

[0128] The dots 150 in the halftone pattern 146 may be characterized by an average dot size. The average dot size may influence whether the gradient in the color density distribution in the transition region 140 is noticeable to a consumer. Decreasing the average size of the dots 150 in the halftone pattern 146 can improve the gradient in the color density distribution and make the color transition in the transition region 140 less noticeable to the consumers.

[0129] Referring again to FIG. 8, in embodiments, the methods of applying the first ink 122 and the second ink 132 to the B surface 106 of the cover glass 102 may include printing or otherwise applying a first pattern of the first ink 122 on the B surface 106, where the first pattern includes a solid pattern in the first BM area 120, a halftone pattern 146 in the transition region 140, and no first ink 122 applied in the second BM area 130. After printing the first pattern of the first ink 122, the methods may include printing a second pattern of the second ink 132 on top of the first pattern of the first ink 122, where the second pattern of the second ink 132 includes a solid pattern in the second BM area 130, a solid pattern in the transition region 140, and none of the second ink 132 applied in the first BM area 120. Thus, on the B surface 106 of the cover glass 102 in the transition region 140, the solid pattern of the second ink 132 may overlap on top of the halftone pattern 146 of the first pattern of the first ink 122. In this configuration, the first ink 122 is in front of the second ink 132 in the transition region 140 when viewed through the cover glass 102 in a direction from the A surface 104 to the B surface 106. The overlap of the solid pattern of the second ink 132 on top of the halftone pattern 146 of the first ink 122 in the transition region 140 may provide the gradient in the color density distribution in the transition region 140, which may result in the smooth transition of the color between the first ink 122 and the second ink 132 in the transition region 140 between the first BM area 120 and the second BM area. In general, the ink comprising the halftone pattern 146 is applied to the B surface 106 of the cover glass 102 in the transition region 140 first and the ink comprising the solid pattern in the transition region 140 is applied overtop of the ink having the halftone pattern 146. Thus, looking through the display cover glass 100 in a direction from the A surface 104 to the B surface 106, the halftone pattern 146 is in front and the solid pattern is behind the halftone pattern 146.Attorney Docket No. SP25-139PCT

[0130] In embodiments, the methods may include applying the first ink 122 in a halftone pattern 146 in the transition region 140, wherein the halftone pattern 146 of the first ink 122 comprises the plurality of dots 150 spaced apart from one another, and applying the second ink 132 in a solid pattern in the transition region 140. In embodiments, the methods may include applying the second ink 132 on top of the halftone pattern 146 of the first ink 122 in the transition region 140. In embodiments, the methods may include applying the first ink 122 in the halftone pattern 146 in the transition region 140, and varying the center-to-center spacing between each of the plurality of dots 150 of the first ink 122 in the halftone pattern 146 from a minimum value at a first end 142 of the transition region 140 to a maximum value at a second end 144 of the transition region 140, where the first end 142 of the transition region 140 borders the first BM area 120 and the second end 144 of the transition region 140 borders the second BM area 130. In embodiments, the methods may include applying the first ink 122 in the halftone pattern 146 in the transition region 140, and varying the size of the plurality of dots 150 in the halftone pattern 146 of the first ink 122 in the transition region 140 from a maximum value at the first end 142 of the transition region 140 to a minimum value at the second end 144 of the transition region 140, where the first end 142 borders the first BM area 120 and the second end 144 borders the second BM area 130.

[0131] In embodiments, the second ink 132 may have the halftone pattern 146 in the transition region 140 and the first ink 122 may have a solid pattern in the transition region 140. In embodiments, the methods may include applying the second ink 132 to the B surface 106 of the cover glass 102 in a second pattern comprising a solid pattern in the second BM area 130 and the halftone pattern 146 in the transition region 140. The methods may include, after applying the second ink 132, applying the first ink 122 in a first pattern comprising a solid pattern in the first BM area 120 and a solid pattern in the transition region 140. Thus, on the B surface 106 of the cover glass 102 in the transition region 140, the solid pattern of the first ink 122 may overlap on top of the halftone pattern 146 of the second ink 132 in the transition region 140. The overlap of the solid pattern of the first ink 122 on top of the halftone pattern 146 of the second ink 132 in the transition region 140 may provide the gradient in the color density distribution in the transition region 140, which may result in the smooth transition of the color between the first ink 122 and the second ink 132 in the transition region 140 between the first BM area 120 and the second BM area.Attorney Docket No. SP25-139PCT

[0132] In embodiments, both the first ink 122 and the second ink 132 may be applied in a halftone pattern 146 in the transition region 140. In embodiments, the methods disclosed herein may include applying the first ink 122 on the B surface 106 of the cover glass 102 in a first pattern, where the first pattern may have a solid pattern in the first BM area 120 and a first halftone pattern in the transition region 140. The methods may further include, after applying the first ink 122, applying the second ink 132 onto the B surface 106 of the cover glass 102 in a second pattern, where the second pattern includes a solid pattern in the second BM area 130 and a second halftone pattern in the transition region 140. The second halftone pattern of the second ink 132 may overlap the first halftone pattern of the first ink 122 in the transition region 140. The overlap of the second halftone pattern of the second ink 132 on top of the first halftone pattern of the first ink 122 in the transition region 140 may provide the gradient in color density distribution in the transition region 140 between the first ink 122 in the first BM area 120 and the second ink 132 in the second BM area 130.

[0133] Referring now to FIGS. 11 and 12, in addition to introducing a gradient in the color density distribution using a halftone pattern and varying the dot characteristics (size, shape, spacing), other printing technologies, such as but not limited to inkjet printing, spray printing, transfer printing etc., could also be used to produce the gradient in the color density distribution in the transition region 140. In embodiments, the gradient in color density distribution in the transition region 140 can be achieved by printing progressively different shades of color from one side of the transition region 140 to the other side. Referring now to FIG. 11, different shades of gray that can be introduced by an inkjet printing method are shown. FIG. 12 shows the inkjet printing method used for introducing the gradient in color density distribution in the transition region 140. The inkjet printing method can produce a "seamless" gradient color change from the first ink 122 (e.g., having a lower L* value) to the second ink 132 (e.g., having a higher L* value compared to the first ink 122). When adjusting the inkjet printing parameters, like printing density, different inks with different L* values, a* values, b* values or combinations thereof can be produced.

[0134] In embodiments, producing the gradient in the color density distribution in the transition region 140 may include inkjet printing a plurality of different shades in succession from the first side 142 of the transition region 140 to the second side 144 of the transition region 140, where the plurality of different shades in succession transitions the color gradually from the color of the first ink 122 in the first BM area 120 to the color of the second ink 132 in theAttorney Docket No. SP25-139PCTsecond BM area 130. Other printing methods may also be used to print a succession of different shades of color in the transition region 140. In embodiments, the methods may include applying the first ink 122 in the first BM area 120, applying a plurality of shades of color in succession in the transition region 140, where the plurality of shades of color vary in L* value, a* value, b* value, or combinations thereof from the first side 142 to the second side 144 of the transition region 140, and applying a second ink 132 in the second BM area 130. In embodiments, the methods may further include applying the second ink 132 on top of the plurality of shades of color in the transition region 140. In embodiments, the method may include printing a first color in the first BM area 120, where the first color may be matched to the reflected color of the first display unit 12 (FIG. 2); printing a second color in the second BM area 130, where the second color may be color-matched to the reflected color of the second display unit 14 (FIG.2); and printing a plurality of shades of color in succession in the transition region 140, where the plurality of shades of color vary in L* value, a* value, b* value, or combinations thereof from the first side 142 to the second side 144 of the transition region 140. The plurality of shades of color in the transition region 140 may gradually transition the color from the first color in the first BM area 120 to the second color in the second BM area 130 to produce the gradient in color density distribution in the transition region 140.

[0135] The subject matter disclosed herein is described in the context of a display assembly having two display units coupled to the display cover glass 100. However, the display assemblies 10 disclosed herein can have more than two display units, such as a third display unit, a fourth display unit, a fifth display unit, and so on. Referring now to FIG. 13, in embodiments, the display assembly 10 may include a third display unit 16 coupled to the display cover glass 100. The methods disclosed herein may further include applying a third ink 162 to the B surface 106 of the cover glass 102 in a third BM area 160, wherein the third BM area 160 surrounds a third visual area 114 associated with the third display unit 16. The third ink 162 may have a color different from the color of the first ink 122, the color of the second ink 132, or both. The third ink 162 may be color matched to the reflected color of the third display unit 16 when the third display unit 16 is turned off. The methods herein may further include applying the second ink 132 and the third ink 162 to the B surface 106 of the cover glass 102 in a supplemental transition region 170 disposed between the second BM area 130 and the third BM area 160, wherein the supplemental transition region 170 has a gradient in aAttorney Docket No. SP25-139PCTcolor density distribution of the second ink 132, the third ink 162, or both between the second BM area 130 and the third BM area 160. The gradient in the color density distribution in the supplemental transition region 170 may be accomplished according to any of the methods previous discussed herein, such as by applying the second ink 132, the third ink 162, or both in a halftone pattern in the supplemental transition region 170 or by printing a gradual color gradient comprising continuously varying shades of color in the supplemental transition region 170 to transition between the color of the second ink 132 and the color of the third ink 162.

[0136] The methods disclosed herein produce a display cover glass 100 for multiple different display units having different reflected colors when turned off, where the display cover glass 100 exhibits improved color matching of each black matrix area to the reflected colors of each of the multiple different display units and a smooth transition in color in transition regions between each of the black matrix areas. The result is a display cover glass 100 that, when coupled to the display units to produce a display assembly, produces a dead front effect with a smooth color transitions between regions and no step change in color between black matrix areas that can be perceived by human vision.

[0137] Referring again to FIGS. 1 and 2, the display cover glass 100 for multiple display units includes a cover glass 102 having the A surface 104 and the B surface 106 opposite the A surface 104. The B surface 106 may comprise the first visual area 110, the second visual area 112, the first BM area 120 surrounding the first visual area 110, the second BM area 130 surrounding the second visual area 112, and the transition region 140 disposed between the first BM area 120 and the second BM area 130. The first BM area 120 may have the first ink 122 applied to the B surface 106 of the cover glass 102, and the second BM area 130 may have the second ink 132 applied to the B surface 106 of the cover glass 102, wherein the second ink 132 has color different from a color of the first ink 122. The transition region 140 may comprises the first ink 122 and the second ink 132 applied to the B surface 106 of the cover glass 102. The transition region 140 may have a gradient in a color density distribution of the first ink 122, the second ink 132, or both between the first BM area 120 and the second BM area 130. The first visual area 110 may be associated with the first display unit 12, and the second visual area may be associated with the second display unit 14. The cover glass 102, first ink 122, and second ink 132 may have any of the properties or features previously discussed herein for the cover glass, first ink, and second ink.Attorney Docket No. SP25-139PCT

[0138] The first visual area 110 and the second visual area 112 are both regions of the display cover glass 100 associated with a particular display unit and function to allow images from the display unit to pass through the display cover glass 100 so that the images are visible to a user looking at the A surface 104 of the display cover glass 100. The first visual area 110 and second visual area 112 are shown in FIGS. 1 and 2 as being rectangular, but can have any convenient or desired shape, which may depend on the shape of the display units. It is understood that the visual areas herein are not intended to be limited by shape. In embodiments, Each of the visual areas, such as the first visual area 110 and / or the second visual area 112, may have an area that is the same as or slightly smaller than a screen area of the display unit associated with the visual area. The first visual area 110 and the second visual area 112 may be spaced apart from one another to provide for the transition region 140 between the first BM area 120 and the second BM area 130. No inks, such as opaque inks, are applied to the B surface 106 of the display cover glass 100 in the first visual area 110, the second visual area 112, or any of the other visual areas of the display cover glass 100.

[0139] Referring again to FIGS. 1 and 2, the display cover glass 100 disclosed herein may have the first BM area 120 and the second BM area 130, which may each have an opaque ink applied to the B surface 106 of the cover glass 102 to prevent light from passing through the display cover glass 100 in the areas surrounding the visual areas. Thus, the BM areas (first BM area 120, second BM area 130, and any other BM areas) ensure that the only light passing through the display cover glass 100 comes from the display units, when turned on, and passes through the visual areas (first visual area 110 and / or second visual area 112). The first BM area 120 may completely surround the first visual area 110, and the second BM area 130 may completely surround the second visual area 112. In embodiments, the first BM area 120 and second BM area 130 may slightly overlap the edges of the screens of the first display unit 12 and second display unit 14, respectively.

[0140] The display cover glass 100 disclosed herein has the transition region 140 disposed between the first BM area 120 and the second BM area 130. The transition region 140 may include a portion of or all of the region between the first visual area 110 and the second visual area 112. In embodiments, the transition region 140 may be spaced apart from the first visual area 110 and the second visual area 112 so that at least a portion of the first BM area 120 is between the first visual area 110 and the transition region and at least a portion of the secondAttorney Docket No. SP25-139PCTBM area 130 is disposed between the second visual area 112 and the transition region 140. The transition region 140 may cover an area between the first BM area 120 and the second BM area 130 so that the first BM area 120 does not abut against the second BM area 130 at any part of the display cover glass 100.

[0141] Referring to FIG. 2, the transition region 140 may have one or more opaque inks, such as but not limited to the first ink 122, the second ink 132, or both applied to the B surface 106 of the display cover glass 100. The transition region 140 may have a gradient in the color density distribution from the color of the first ink 122 in the first BM area 120 to the color of the second ink 132 in the second BM area 130. This results in the transition region 140 having smooth color transition between the color of the first ink 122 in the first BM area 120 to the color of the second ink 132 in the second BM area 130. In embodiments, the transition region 140 may have a color density distribution of the first ink 122, the second ink 132, or both between the first BM area 120 and the second BM area 130.

[0142] In embodiments, the display cover glass 100 has no step change in color that is identifiable with the human eye in the transition region 140 between the first BM area 120 and the second BM area 130. In embodiments, the display cover glass 100 may have no step change in color that is identifiable by the human eye between the first BM area 120 and the transition region 140 and between the second BM area 130 and the transition region 140. In embodiments, the display cover glass 100 may have a gradual color transition between the first BM area 120 and the second BM area 130 in the transition region 140.

[0143] In embodiments, the display cover glass 100 does not have any coatings is the first visual area 110 and second visual area 112 that reduce the transmission of light through the display cover glass 100. When the display cover glass 100 is incorporated into a display assembly 10 comprising at least a first display unit 12 and a second display unit 14, the display assembly 10 has a brightness of greater than or equal to 1,000 candelas / m2.

[0144] In embodiments, the transition region 140 may have a gradient in the spatial density distribution of the first ink 122, the second ink 132, or both, which provides the gradient in color density distribution in the transition region 140. The spatial density distribution is defined as a coverage area of an ink per unit area of the B surface 106 of the display cover glass 100. In embodiments, the transition region 140 may have a spatial density distribution of the first ink 122, the second ink 132, or both that varies based on position within the transition regionAttorney Docket No. SP25-139PCT140, such as based on the relative distance from the first BM area 120 to the second BM area 130.

[0145] Referring again to FIG. 8, in embodiments, the transition region 140 may have a halftone pattern of the first ink 122, the second ink 132, or both, where the halftone pattern 146 comprises a plurality of dots 150, which provides the spatial density distribution of the inks in the transition region 140. In the transition region 140, a size of the plurality of dots 150, a center-to-center spacing of the plurality of dots 150, or both of the halftone pattern 146 vary with position within the transition region 140 to provide the spatial density distribution. In embodiments, the transition region 140 may include a halftone pattern 146 of the first ink 122 and a solid pattern of the second ink 132. The solid pattern of the second ink 132 may be applied on top of the halftone pattern 146 of the first ink 122 such that the halftone pattern 146 of the first ink 122 is disposed between the solid pattern of the second ink 132 and the B surface 106 of the cover glass 102. The halftone pattern 146 of the first ink 122 may be adhered to and in direct contact with the B surface 106 of the cover glass 102. The halftone pattern 146 of the first ink 122 may have a pattern in which the size of the plurality of dots 150, the center-to-center spacing of the dots 150, or both vary with position within the transition region 140 between the first BM area 120 and the second BM area 130 in order to produce the color density distribution of the first ink 122 and the second ink 132 in the transition region 140.

[0146] In embodiments, the halftone pattern 146 of the first ink 122 comprises dots 150 having a size that is fixed and constant, and the center-to-center spacing between each of the dots 150 varies depending based on position of each of the plurality of dots 150 in the transition region 140 between the first BM area 120 and the second BM area 130. The center-to-center spacing between each of the plurality of dots 150 of the halftone pattern 146 of the first ink 122 may have a minimum value at the first end 142 of the transition region 140 and a maximum value at the second end 144 of the transition region 140, where the first end 142 of the transition region 140 borders the first BM area 120 and the second end 144 of the transition region 140 borders the second BM area 130. In embodiments, the halftone pattern 146 of the first ink 122 comprises dots 150 having center-to-center spacing between each of the dots 150 that is fixed and constant, and the size of each of the plurality of dots 150 varies depending based on position of each of the plurality of dots 150 in the transition region 140 between the first BM area 120 and the second BM area 130. The size of each of the plurality of dots 150 of the halftone patternAttorney Docket No. SP25-139PCT146 of the first ink 122 may have a minimum value at the first end 142 of the transition region 140 and a maximum value at the second end 144 of the transition region 140.

[0147] The halftone pattern 146 has been described herein in terms of the first ink 122 having the halftone pattern 146. However, in embodiments, the second ink 132 may have the halftone pattern 146 and the first ink 122 may be a solid pattern in the transition region 140. When the second ink 132 has the halftone pattern 146, the size, center-to-center spacing, or both of the dots in the halftone pattern 146 of the second ink 132 can be varied with position to produce the spatial density distribution of the first ink 122 and the second ink 132. In embodiments, both the first ink 122 and the second ink 132 may comprise a halftone pattern 146 in the transition region 140, as long as the entire transition region 140 is covered in an opaque ink and no gaps exist between dots of the halftone patterns 146.

[0148] Other methods may also be used to produce the color gradient in the transition region 140 between the first BM area 120 and the second BM area 130. Referring again to FIG.12, in embodiments, the transition region 140 may comprise progressively different shades of color applied to the B surface 106 of the cover glass 102 from first side 142 of the transition region 140 to the second side 144 of the transition region 140, where the progressively different shades of color gradually transition the color from the color of the first ink 122 in the first BM area 120 to the color of the second ink 132 in the second BM area 130.

[0149] Referring again to FIG. 13, in embodiments, the display cover glass 100 may comprise a third visual area corresponding to a third display unit 16, a third BM area 160 surrounding the third visual area, and a supplemental transition region 170 disposed between the second BM area 130 and the third BM area 160. The third BM area 160 may comprise a third ink 162 applied to the B surface 106 of the cover glass 102. The third ink 162 may be different from the first ink 122, the second ink 132, or both. The third ink 162 may have a color that is different from the color of the first ink 122, the color of the second ink 132, or both. In embodiments, the third BM area 160 may be adjacent to the second BM area 130, the display cover glass 100 may include the supplemental transition region 170 disposed between the second BM area 130 and the third BM area 160, and the supplemental transition region 170 may include the second ink 132 and the third ink 162 applied to the B surface 106 of the cover glass 102. The supplemental transition region 170 may have a gradient in the density distribution of the second ink 132, the third ink 162, or both between the second BM area 130 and the third BM area 160. In embodiments, the third BM area 160 may be adjacent to the firstAttorney Docket No. SP25-139PCTBM area 120, the display cover glass 100 may comprise the supplemental transition region 170 disposed between the first BM area 120 and the third BM area 160, and the supplemental transition region 170 may comprise the first ink 122 and the third ink 162 applied to the B surface 106 of the cover glass 106. The supplemental transition region 170 may have a gradient in the density distribution of the first ink 122, the third ink 162, or both between the first BM area 120 and the third BM area 160.

[0150] In many cases, the gradient in the color density distribution in the transition region 140 or supplemental transition region 170 is sufficient to produce a display cover glass 100 that presents a dead front effect when the display units are turned off. However, in some cases the difference in color between the display units, such as between the first display unit 12 and the second display unit 14 or between the second display unit 14 and the third display unit 16, is great enough that the color change is noticeable to a consumer, even with the gradient in color density distribution in the transition region 140 or supplemental transition region 170. Referring again to FIG. 12, in embodiments, the display cover glass 100 may include a semitransparent antireflective (STAR) coating 180 applied to the A surface 104 of the cover glass 102. The STAR coating 180 of the present disclosure has a higher transmittance compared to the STAR coatings used in conventional methods. The STAR coating 180 may have a transmittance (Tx) of visible light of greater than or equal to 60%, such as from 60% to 99%. The methods disclosed herein may further include the step of applying the STAR coating 180 to the A surface 104 of the cover glass 102. The STAR coating 180 having a Tx of greater than or equal to 60% may reduce the transmittance enough to reduce the AE between the first BM area 120 and the second BM area 130 to mask any remaining color differences while also allowing enough light to pass through to maintain the brightness of the display units at a level meeting consumer expectations.

[0151] The STAR coating 180 may be a multilayer coating having an anti -refl ection layer and an adsorption layer. The absorption layer may provide absorption of light that reduces the transmittance of the display cover glass. In embodiments, the STAR coating 180 may have a transmittance Tx of greater than or equal to about 60%, such as from about 60% to about 99%, from about 60% to about 95%, or from about 65% to about 90%. In embodiments, the STAR coating 180 may be an 85 STAR coating having a transmittance of about 85%. In embodiments, the STAR coating 180 may be a 70 STAR coating, which has a transmittance of about 70%. InAttorney Docket No. SP25-139PCTembodiments, the STAR coating may comprise a stacked coating comprising a plurality of layers, such as but not limited to a first stack of alternating layers of silica (SiCh) and niobium (Nb) applied onto the glass surface followed by a second stack of alternating layers of silica (SiCh) and niobium oxideon top of the first stack. In embodiments, the first stack may have from 1 to 20 pair of alternating layers of SiC>2 and Nb (2 to 20 total layers). The number of alternating Si O2 and Nb layers in the first stack may influence the transmittance through the STAR coating. In one non-limiting example, the STAR coating may have the first stack comprising six pair of alternating SiCh / Nb layers and a second stack comprising three SiCh layers alternating with two Nb2Os layers deposited onto the first stack (total of 17 layers), and may have an average transmittance (Tx) of 86% and an absorption of 13.7% over the visible spectrum range. This example is provided for purposes of enablement, and it is understood that other configurations and materials for the STAR coating are contemplated.

[0152] Referring now to FIG. 14, the Rx spectrum (received signal spectrum) and Tx spectrum (transmitted signal spectrum) of a STAR coating having a transmittance Tx of about 60% is graphically depicted. For FIG. 14, three positions of the STAR coating 180 are measured for Rx using a SPHERE™ 3000 spectrum analyzer from Sigi ent Technologies and for Tx using a TMS-pro analyzer obtained from Guangzhou BIAOQI Optoelectronics Technology Development Co., LTD in Guangzhou, China. The results in FIG. 14 show that the uniformity of the STAR coating is good, the average Rx (Specular Component Included (SCI)) of the STAR coating is equal to about 0.21%, and the average Tx (SCI) of the STAR coating is equal to about 57.1%. This means that the whole display assembly could achieve a transmittance (Tx) of greater than about 61%, with the 4% improvement in Tx when the display cover glass 100 comprising the STAR coating 180 is bonded with the display units underneath without an air gap. This will improve the brightness performance by almost double compared with a conventional method in which only the STAR coating with a Tx of about 30% is applied for reducing the color difference (AE).

[0153] Referring now to FIG. 15, the color performance of the STAR coating 180 is evaluated. Measured results of the Rx color and Tx color are presented in FIG. 15 with respect to the a* value (y-axis) and the b* value (x-axis). As shown in FIG. 15, the Rx color stays in the 3rdquadrant of color coordinates chart, which indicates a bluish color. The bluish color is the color that most vehicle makers expect from the display assembly 10. Thus, the application of the STAR coating 180 to the A surface 104 of the display cover glass 100 is not expected toAttorney Docket No. SP25-139PCThave a significant effect on the color of the black matrix areas or the images displayed by the display units when turned on.

[0154] Referring again to FIG. 12, as previously discussed, the STAR coating 180 may be applied to the A surface 104 of the cover glass 102. The STAR coating 180 may be applied to the entire A surface 104 of the cover glass 102, including in the first visual area 110, the second visual area 112, the first BM area 120, the second BM area 130, and the transition region 140.

[0155] The visual areas, such as the first visual area 110 and the second visual area 112, may each have a transmittance of greater than 60% of the light produced by the first display unit 12 and the second display unit 14 when the display units are turned on. In embodiments, a display assembly 10 comprising the display cover glass 100 having the STAR coating 180 and coupled to the first display unit 12 and the second display unit 14 may have a maximum brightness of greater than or equal to about 500 candelas / m2, such as greater than or equal to 1,000 candelas / m2, from about 500 candelas / m2to about 2,500 candelas / m2, from about 500 candelas / m2to about 2,000 candelas / m2from about 500 candelas / m2to about 1,500 candelas / m2, from about 500 candelas / m2to about 1,000 candelas / m2, from about 1,000 candelas / m2to about 2,500 candelas / m2, from about 1,000 candelas / m2to about 2,000 candelas / m2from about 1,000 candelas / m2to about 1,500 candelas / m2, from about 1,500 candelas / m2to about 1,500 candelas / m2, from about 1,500 candelas / m2to about 2,000 candelas / m2, or any range or subrange therebetween, when the first display unit 12 and the second display unit 14 are turned on. The brightness refers to the brightness measured with a colorimeter in a 5,000 lux D65 illumination environment according to the standard test method in SAE Standard J 1757 / 1 for standard metrology for vehicular displays. In some circumstances, the different display units may be close enough in reflected color in the off condition that a dead front effect of the display cover glass can be achieved using a single tunable ink in the BM areas of the cover glass in combination with a STAR coating having a transmittance Tx of greater than or equal to about 60%. The concept is to achieve good color-matching through a two-step method, in which the first step is applying a single tunable ink to the B surface of the cover glass in the BM areas for color matching of the display panels to a certain level. The second step is then to further reduce the color difference AE between the display panels and between each display panel and the BM area by applying a STAR coating with a relatively high transmittance. The STAR coating may have transmittance Tx of greater than or equal to aboutAttorney Docket No. SP25-139PCT60%, which can maintain the vehicle display units at an appropriate brightness level while still providing a color-matched appearance resulting in a dead front effect when the display units are turned off. While simple in concept, the tradeoff is that the single tunable ink cannot exactly match with any one of the plurality of different display units, but rather seeks a middle ground between them. Thus, the STAR coating is added to further mask the difference between the single tunable ink and reflected colors of the multiple display units.

[0156] Referring now to FIGS. 16 and 17, in embodiments, the display cover glass 100 may include the cover glass 102 having the A surface 104 and the B surface 106. Referring to FIG. 16, the display cover glass 100 may have the first visual area 110, the second visual area 112, and a single BM area 190 that surrounds both the first visual area 110 and the second visual area 112. Referring now to FIG. 17, a cross-section of a display assembly 10 comprising the display cover glass 100 of FIG. 16 is schematically depicted. The display cover glass 100 includes a single tunable ink 192 applied to the B surface 106 of the cover glass 102 in the single BM area 190. The display cover glass 100 may have no ink applied to the B surface 106 of the cover glass 102 in the first visual area 110 and the second visual area 112. The display cover glass 100 may include the STAR coating 180 applied to the A surface 104 of the cover glass 102, where the STAR coating 180 may have a transmittance of greater than or equal to about 60%. The display assembly 10 may have the first display unit 12 and the second display unit 14 attached to the B surface 106 of the cover glass 102 with an adhesive layer 182. The first display unit 12 may be associated with the first visual area 110 and the second display unit 14 may be associated with the second visual area 112. The display cover glass 100 is described in terms of having two visual areas to accommodate two display units, however, it is understood that the display cover glass may have more than 2 visual areas (e.g., 2, 3, 4 or more than 4 visual areas) to accommodate more than 2 display units (e.g., 2, 3, 4, or more than 4 display units), as previously discussed herein.

[0157] Referring now to FIG. 18, the concept of the single tunable ink 192 in the single BM area 190 is schematically depicted. In order to achieve a certain target L* of the single tunable ink 192, the single tunable ink 192 can include a mixture of two base inks: a first base ink 194 having a first color and a second base ink 196 having a second color. For the sake if illustration using drawings being in black and white, the color differences between the first bse ink 194 and the second base ink 196 will be described in terms of L* value. However, it is understood that the first base ink 194 and second base ink 196 can have the same or differentAttorney Docket No. SP25-139PCTa* or b* values as well. The first base ink 194 and second base ink 196 can be formulated based on L* value, a* value, b* value, or any combinations of these. As shown in FIG. 18, in embodiments, the first base ink 194 may have lower L* performance and the second base ink 196 may have a higher L* performance. The first BM ink 194 having the lower L* performance and the second BM ink 196 having the higher L* performance can be mixed together in a designed ratio to get the specific optical performance in terms of L* value for the single tunable ink 192. The specific ratio of the first base ink 194 and the second base ink 196 may be selected so that the single tunable ink 192 in combination with the STAR coating 180 appears to be exactly the same as the reflected colors of the display units (first display unit 12 and second display unit 14) when the display units are turned off, which provides a dead front effect when the display units are turned off. In embodiments, the specific ratio of the first base ink 194 and the second base ink 196 may be selected so that the single tunable ink 192 has a color, such as an L* value, a* value, b*value, or combinations thereof, that is an average between the reflected color of the first display unit 12 and the reflected color of the second display unit 14, when both are in the off condition.

[0158] Referring now to FIG. 19, the SCI L* value (y-axis) as a function of a ratio of a first base ink to a second base ink (x-axis) for one embodiment of a single tunable ink disclosed herein is schematically depicted. FIG. 20 graphically depicts the SCE L* value (y-axis) as a function of the ratio of first base ink to the second base ink (x-axis) for the single tunable ink. FIGS. 19 and 20 show the concept of the single tunable ink in which a low L* ink and a high L* ink are selected as the first base ink and the second base ink. As shown in FIGS. 19 and 20, mixing with different ratios of the low L* ink to the high L* ink can produce tunable inks with a broad range of different L* values, and a good linear relationship exists between the L* value of the tunable ink and the ratio of the low L* ink to the high L* ink. Table 1 presents color data for different single tunable inks applied to a display cover glass comprising GORILLA GLASS® from Corning Incorporated.Table 1Attorney Docket No. SP25-139PCT

[0159] Referring again to FIGS. 16 and 17, a display assembly 10 comprising a first display unit 12, a second display unit 14, and the display cover glass 100 having the single tunable ink 192 and STAR coating 180 is schematically depicted. The first display unit 12 and the second display unit 14 may have different reflected colors when the display units are turned off. The STAR coating 180 may be applied to the A surface 104 of the cover glass 102, which is the side of the display cover glass 100 opposite the side of the display cover glass 100 to which the first display unit 12 and second display unit 14 are attached. The single tunable ink 192 may be applied to the side of the display cover glass 100 to which the display panels are bonded. Based on the Rx% and optical performance of the first display unit 12 and the second display unit 14 (i.e., the reflected colors of the display units when they are turned off), a median value for L*, a*, and b* between the two display units can be determined based on the L*, a*, and b* of each display, and the single tunable ink can be formulated to achieve the median value of L*, a*, and b* to come as close as possible to color matching each of the display units. The STAR coating 180 can then be applied to the display cover glass 100 to further mask the color differences to improve the color matching. Although described in the context of two display units, the same technique may be used to improve color matching when more than two display units are bonded to the display cover glass 100. The first display unit 12 and the second display unit 14 may be bonded to the display cover glass 100 with an adhesive layer 182, according to known methods. The adhesive layer 182 may be an optically clear adhesive (OCA).

[0160] Referring to FIGS. 16 and 17, the display cover glass 100 -which is for the display assembly 10 having the first display unit 12 and the second display unit 14 - may include at least a cover glass 102, the first visual area 110, the second visual area 112, and the single BM area 190 surrounding the first visual area 110 and the second visual area 112. The cover glass 102 may have an A surface 104 and a B surface 106. The single BM area 190 may include the single tunable ink 192 applied to the B surface 106 of the cover glass 102. The single tunable ink 192 may have a color that is between a first color reflected by the first display unit 12 inAttorney Docket No. SP25-139PCTthe off condition and a second color reflected by the second display unit 14 in the off condition, wherein the first color is different from the second color. In embodiments, the color of the single tunable ink 192 may be a median color between the first color and the second color. The display cover glass 100 may further include the STAR coating 180 applied to the A surface 104 of the display cover glass 100. The STAR coating 180 may be applied in the first visual area 110, the second visual area 112, and the single BM area 190.

[0161] In embodiments, when the first display unit 12 is turned off, the first display unit 12 may reflect the first color, and when the second display unit 14 is turned off, the second display unit 14 may reflect a second color different from the first color. The first color of the first display unit 12 may have a first L*, a first a*, and a first b*; the second color of the second display unit 14 may have a second L*, a second a*, and a second b*; and the ink color of the single tunable ink 192 may have an ink L*, an ink a*, and an ink b*. The first L* may be different from the second L*, the first a* may be different from the second a*, the first b* may be different from the second b*, or combinations thereof. The ink L* may be a median value between the first L* and the second L*, the ink a* may be a median value between the first a* and the second a*, the ink b* may be a median between the first b* and the second b*, or any combinations thereof. In embodiments, the STAR coating 180 has a transmittance (Tx) of greater than or equal to 60%, such as from 60% to 90%. The STAR coating 180 may have any of the other features or properties previously discussed herein for the STAR coating 180.

[0162] In embodiments, the display cover glass 100 may have a third visual area (not shown) corresponding to a third display unit coupled to the B surface 106 of the display cover glass 100 in the third visual area. When the third display unit is turned off, the third display unit may reflect a third color different from the first color, the second color, or both. The third color of the third display unit may have a third L*, a third a*, and a third b*. The ink color of the single tunable ink 192 may satisfy one or more of the following conditions: (1) the ink L* of the single tunable ink 192 may be an average of the first L*, the second L*, and the third L*; (2) the ink a* of the single tunable ink 192 may be an average of the first a*, the second a*, and the third a*; (3) the ink b* of the single tunable ink 192 may be an average of the first b*, the second b*, and the third b*; or (4) any combinations thereof. In embodiments, the display cover glass 100 may be configured to accommodate more than 3 display units, such as but not limited to 4 display units or more than 4 display units.Attorney Docket No. SP25-139PCT

[0163] Referring again to FIGS. 16 and 17, in embodiments, the methods disclosed herein may include providing the first display unit 12 and the second display unit 14 having L*, a*, b* values different from the first display unit 12 and determining a median L* value, a median a* value, a median b* value, or combinations thereof from the L*, a*, and b* values of the first display unit 12 and the second display unit 14. The methods may further include formulating a single tunable ink 192 based on the median L* value, the median a* value, the median b* value, or combinations thereof. The methods may further include applying the single tunable ink 192 to the single BM area 190 of the display cover glass 100. The single tunable ink 192 may be applied to the B surface 106 of the display cover glass 100. The methods may further include applying the STAR coating 180 having a Tx of greater than or equal to about 60% to the A surface 104 of the display cover glass 100, which is opposite the B surface 106 having the single tunable ink 192 applied thereto. The method may further include bonding the first display unit 12 and the second display unit 14 to the B surface 106 of the display cover glass 100. In embodiments, the single tunable ink 192 may be a mixture of the first base ink 194 and the second base ink 196, where a ratio between the first base ink 194 and the second base ink 196 may be adjusted to achieve the desired median L* value, median a* value, and / or median b* value.

[0164] In other embodiments, the methods herein for making the display cover glass 100 may include determining a first L* value, a first a* value, a first b* value, or combinations thereof for a first color of a first display unit 12, where the first color is a color reflected when the first display unit 12 is turned off, and determining a second L* value, second a* value, a second b* value, or combinations thereof for a second display unit 14 having a second color, where the second color is a color reflected when the second display unit 14 turned off. The Second color may be different from the first color. The methods may further include determining one or more of a median L* value from the first L* value and the second L*value, a median a* value from the first a* value and the second a* value, a median b* value from the first b* value and the second b* value, or any combinations thereof. The methods may further include formulating the single tunable ink 192 having the median L* value, the median a* value, the median b* value, or combinations thereof, and applying the single tunable ink 192 to the single BM area 190 of the B surface 106 of display cover glass 100. The methods may further include applying STAR coating 180 to the A surface 104 of display cover glass 100. In embodiments, the single tunable ink 192 may be a mixture of a first base ink 194 and a second base ink 196, where a ratio between the first base ink 194 and the second base ink 196 isAttorney Docket No. SP25-139PCTadjusted to achieve the desired L*, a*, and b* values. In embodiments, the display cover glass 100 may be configured to accommodate more than 2 different display units, such as 3, 4 or more than 4 display units. In these embodiments, the single tunable ink 192 may be formulated to have an average L* value, an average a* value, an average b* value, or combinations thereof based on the L* values, a* values, and / or b* values of the plurality of display units.

[0165] Referring again to FIG. 2, the display cover glass 100 disclosed herein may be incorporated into a display assembly 10, which may include the display cover glass 100 and a plurality of display units (e.g., first display unit 12, second display unit 14, or other display units) attached to the B-surface 104 of the display cover glass 100. The display assembly 10 may include the display cover glass 100 bonded to a plurality of display units 12,14, where the display units 12, 14 may be bonded to the B surface 106 of the display cover glass 100, which is the side of the display cover glass 100 to which the inks are applied in the BM areas (e.g., first BM area 120, second BM area 130, or other BM area). The display units 12, 14 may be bonded to the display cover glass 100 so that no air gap is disposed between the display cover glass 100 and the display units 12, 14. The display units 12, 14 may be bonded to the display cover glass 100 by an adhesive layer 182. The adhesive layer 182 may be an optical glue, such as an optically clear adhesive (OCA), or other bonding agent that does not significantly change the optical performance of the display assembly 10. In embodiments, the display assembly 10 does not have a gap comprising a gas or vacuum between the B surface 106 of the display cover glass 100 and the display units, such as but not limited to the first display unit 12, the second display unit 14, or both. In embodiments, any spacing between the B surface 106 of the display cover glass 100 and the display units (e.g., first display unit 12 and second display unit 14) is occupied by the adhesive layer 182 and optionally the inks for the BM areas (i.e., around the edges of the visual areas), and no volume (<0.01 cm3) of gas or vacuum is present between the display units and the B surface 106 of the display cover glass.

[0166] Referring again to FIG. 2, in embodiments, the display assembly 10 may include the display cover glass 100 according to any of the embodiments previously disclosed herein, a first display unit 12 bonded to the B surface 106 of the display cover glass 100 in the first visual area 110, and a second display unit 14 bonded to the B surface 106 of the display cover glass 100 in the second visual area 112. Referring to FIGS. 2 and 5, in embodiments, the first display unit 12 and the second display unit 14 may be directly bonded to the B surface 106 ofAttorney Docket No. SP25-139PCTthe display cover glass 100 in the first visual area 110 and second visual area 112, respectively. Referring again to FIG. 13, in embodiments, the display assembly 10 may include a third display unit 16 attached to the B surface 106 of the display cover glass 100, and the display cover glass 100 may have a third visual area 114 corresponding to the third display unit 16.

[0167] Referring again to FIG. 2, in embodiments, the display cover glass 100 may have the first BM area 120 surrounding the first visual area 110 associated with the first display unit 12 and the second BM area 130 surrounding the second visual area 112 associated with the second display unit 14, which may have a reflected color different from the first display unit 12 when both display units are turned off. The first BM area 120 may include the first ink 122, which has a color that is color matched to the reflected color of the first display unit 12 when the first display unit is turned off, and the second BM area 130 has the second ink 132, which has a color that that is color matched to the reflected color of the second display unit 14 when the second display unit 14 is turned off. In embodiments, the first BM area 120 may overlap the first display unit 12 around the edges of the first visual area 110, and the second BM area 130 may overlap the second display unit 14 around the edges of the second visual area 112.

[0168] The display cover glass 100 may further have the transition region 140 between the first BM area 120 and the second BM area 130, where the transition region 140 provides a gradient in color density distribution between the first ink 122 and the second ink 132. The transition region 140 may have any of the configurations, properties, or characteristics previously described herein for the transition region 140. Referring again to FIG. 13, in embodiments, the display assembly 10 may include the third display unit 16, the display cover glass 100 has the third visual area 114 surrounded by the third BM area 160, and the display cover glass 100 may further include the supplemental transition region 170 between the third BM area 160 and the first BM area 120 or between the third BM area 160 and the second BM area 130. The supplemental transition region 170 may have any of the configurations, features, or characteristics previously described herein for the supplemental transition region 170.

[0169] Referring again to FIG. 12, in embodiments, the display cover glass 100 of the display assembly 10 may include the STAR coating 180 applied to the A surface 104 of the display cover glass 100. The STAR coating 180 may have any of the features, properties, or characteristics previously discussed herein for the STAR coating 180. Referring now to FIGS.16 and 17, in embodiments, the display cover glass 100 of the display assembly 10 may have the single BM area 190, the single tunable ink 192 applied in the single BM area 190, and theAttorney Docket No. SP25-139PCTSTAR coating 180 applied to the A surface 104 of the display cover glass 100. In embodiments, the display assembly 10 may have a brightness of greater than or equal to 1000 candelas / m2when the first display unit 12, and second display unit 14, or both are turned on.

[0170] The display assemblies 10 disclosed herein may be produced by preparing the display cover glass 100 according to any of the methods disclosed herein and bonding the first display panel 12, the second display panel 14, and any other display panels to the B surface 106 of the display cover glass 100. Referring to FIGS. 1 and 2, in embodiments, the methods of making the display assembly 10 may include preparing the display cover glass 100 according to the methods disclosed herein, coupling the first display unit 12 to the B surface 106 of the display cover glass 100 in the first visual area 110, and coupling the second display unit 14 to the B surface 106 of the display cover glass 100 in the second visual area 112. In embodiments, the methods of making the display assembly 10 may include bonding the first display unit 12, and second display unit 14, and any other display unit directly to the B surface 106 of the display cover glass 100 their respective visual areas.EXAMPLES

[0171] The following examples are offered to illustrate specific embodiments disclosed herein. It should be understood that the following examples are for purposes of description only and are not intended to limit the scope of the claimed subject matter.

[0172] Comparative Example 1: Single Ink Color Matching

[0173] In Comparative Example 1, a display cover glass for two different display units is prepared using a single ink in a single BM area. For Comparative Example 1, the first display unit, associated with the first visual area, has a reflected color having L*, a*, b* = 9, -2, -3, respectively, when turned off, and the second display panel, associate with the second visual area, has a slightly different reflected color with L*, a*, b* = 14, -1, -2, respectively, when turned off. The best color matching by the conventional method of Comparative Example 1 was achieved using a single ink material that produced the same color average of L*, a*, b* = 11.5, -1.5, -2.5, respectively, for both the first visual area and the second visual area. No STAR coating was applied to the display cover glass in Comparative Example 1.

[0174] The AE was then calculated between the color of the first display unit and the color of the single BM area and between the color of the second display unit and the single BM area.Attorney Docket No. SP25-139PCTThe results for the AE for the first display unit and second display unit are provided in Table 2. The AE for the first display unit and second display unit were both equal to 2.6. Changing the color of the ink in the single BM area could reduce the AE between one of the display units and the BM area, however, the AE between the other display unit and the single BM area would then increase. Therefore, Comparative Example 1 shows that achieving the same color average of the ink in a single BM region as the best color matching is considered the optimal solution for the conventional color matching methods but does not eliminate all the color matching issues. Differences in color are still observable between the single BM area and each of the display units.

[0175] Example 2: Two Tunable Inks and Transition Region

[0176] In Example 2, a display cover glass having a different BM area with a different ink for each of a first display unit and a second display unit was produced to improve color matching between each visual area and the black matrix area surrounding the visual area. Referring to FIGS. 1 and 2, the display cover glass 100 was made with a first BM area 120 surrounding the first visual area 110 for the first display unit 12, a second BM area 130 surrounding the second visual area 112 for the second display unit 14, and a transition region 140 between the first BM area 120 and the second BM area 130. The first display unit 12 and the second display unit 14 were the same as those used in Comparative Example 1, the reflected colors of which are provided in Table 2. For Example 2, the first BM area 110 included a first ink having a first color that was color matched to the reflected color of the first display unit 12 in the off condition. The second BM area 112 had a second ink having a second color different from the first color, where the second color was matched to the reflected color of the second display unit 14 in the off condition. Thus, the AE between the first display unit and the first ink in the first BM area is equal to about zero, and the AE between the second display unit and the second ink in the second BM area is equal to about zero, as indicated in Table 2.Table 2Attorney Docket No. SP25-139PCT

[0177] In the transition region 140 of the display cover glass of Example 2, the color is gradually transitioned between the first color of the first ink in the first BM area 120 to the second color of the second ink in the second BM area 130. The transition region 140 of Example 2 was made by printing the first ink in a pattern comprising a plurality of dots in the transition region, where the plurality of dots were of equal size and the center-to-center spacing between the plurality of dots was varied from one side to the other side of the transition region. The transition region 140 exhibited a gradient in color density distribution of the first ink and the second ink that provided a smooth color transition between the first color of the first BM area and the second color of the second BM area. Referring now to FIG. 3, an image of the display assembly comprising the display cover glass of example 2, the first display unit and the second display unit indicates that the display assembly has excellent color matching between each display unit and its associate BM area and exhibits a smooth transition of color between the two BM areas that presents a dead front effect when the display units are turned off.

[0178] Example 3: Printing a Color Gradient in the Transition Region

[0179] In Example 3, the color gradient in the transition region between the first BM area and the second BM area is produced through printing and varying the print density through the transition region. FIG. 11 shows shades of color that can be introduced by an inkjet printing method. FIG. 12 shows the inkjet printing method used for introducing the color gradient in the transition region of the display cover glass. In Example 3, the first BM area 120 was printed with a first ink having a low L*value of about 26.54 and the second BM area 130 was printed with a second ink having a high L* value of about 28.96. An inkjet printing method was used to produce a "seamless" gradient color change from the first ink (low L*) to the second inkAttorney Docket No. SP25-139PCT(high L*) by adjusting inkjet printing parameters, such as printing density. When adjusting the inkjet printing parameters, like printing density, different levels of L* BM ink can be achieved. The following Table 3 shows that the L* values in the transition region were precisely tuned from 26.54 to 28.96 with the adjustment of the printing density from 66 to 44. Example 3 shows that, in addition to introducing a gradient in dot size, shape, or spacing, other printing technologies, such as but not limited to inkjet printing, spray printing, transfer printing, etc., also could be used to produce the color gradient in the transition region.Table 3

[0180] Example 4: Single Tunable Ink and STAR Coating

[0181] In Example 4, a display cover glass having a first visual area, a second visual area, a single BM area surrounding the first visual area and second visual area, and a STAR coating applied to the A surface of the display cover glass was evaluated in a display assembly comprising a first display unit and a second display unit. In Example 4, the first display unit was an LCD panel display unit having a reflected color in the off condition characterized by L* value = 9.69, a* value = -1.48, b* value = -0.16, andanRx(Y)* value = 1.09, and the second display unit was an LCD panel display unit having a reflected color in the off condition characterized by L* value = 15.17, a* value = -0.22, b* value = -7.04, and an Rx(Y)* value = 1.94. The single BM area was then coated with a single tunable ink having L*, b*, and a* values that were halfway between the L*, b*, and a* values, respectively, of the first display unit and second display unit. The display cover glass was then coated on the A surface with a STAR coating having a transmittance of equal to about 60%. The B surface of the display coverAttorney Docket No. SP25-139PCTglass was then bonded to the first display unit at the first visual area and was bonded to the second display unit at the second visual area. The color differences AE between the visual areas and the BM area for each display unit were then determined. The color difference for the two-panel display assembly was found to be good with AE<2 by adopting STAR Tx=60%.Table 4

[0182] FIG. 21 shows the actual color appearance between the visual area (VA) and black matrix (BM) area for first display unit of Table 4, and FIG. 22 shows the actual color appearance between the visual area and BM area for the second display unit of Table 4. FIGS.21 and 22 indicate that the color difference is pretty small, and the display assembly presents a deadfront effect as expected (i.e., the entire display appears as one solid color when display panel 1 and display panel 2 are turned off).

[0183] While various embodiments of the methods of improving color matching of display cover glass for vehicles have been described herein, it should be understood that it is contemplated that each of these embodiments and techniques may be used separately or in conjunction with one or more embodiments and techniques.

[0184] It will be apparent to those skilled in the art that various modifications and variations can be made to the embodiments described herein without departing from the spirit and scope of the claimed subject matter. Thus, it is intended that the specification cover the modifications and variations of the various embodiments described herein provided such modification and variations come within the scope of the appended claims and their equivalents.

Claims

1. Attorney Docket No. SP25-139PCTCLAIMSWhat is claimed is:

1. A display cover glass for multiple displays, the display cover glass comprising an A surface and a B surface opposite the A surface, wherein the B surface comprises a first visual area, a first black matrix (BM) area surrounding the first visual area, a second visual area, a second BM area surrounding the second visual area, and a transition region disposed between the first BM area and the second BM area, wherein:the first BM area has a first ink applied to the B surface of the display cover glass, and the second BM area has a second ink applied to the B surface of the display cover glass, wherein the second ink has color different from a color of the first ink; andthe transition region comprises the first ink and the second ink applied to the B surface; andthe transition region has a gradient in a color density distribution of the first ink, the second ink, or both between the first BM area and the second BM area.

2. The display cover glass of claim 1, wherein the first ink and the second ink are both opaque.

3. The display cover glass of claim 1, wherein a spatial density distribution of the first ink, the second ink, or both in the transition region varies with position within the transition region, wherein the spatial density distribution is defined as a coverage area of an ink per unit area of the B surface of the display cover glass.

4. The display cover glass of claim 3, wherein, in the transition region, the first ink, the second ink, or both are applied in a halftone pattern comprising a plurality of dots, wherein a size of the plurality of dots, a center-to-center spacing of the plurality of dots, or both vary with position within the transition region to achieve the spatial density distribution.

5. The display cover glass of claim 4, wherein, in the transition region, the first ink is applied in a halftone pattern comprising a plurality of dots spaced apart from one another and the second ink is applied as a solid pattern.Attorney Docket No. SP25-139PCT6. The display cover glass of claim 5, wherein the second ink is applied on top of the first ink in the transition region.

7. The display cover glass of claim 1, wherein the first ink has a first L* value, a first a* value, and a first b* value; the second ink has a second L* value, a second a* value, and a second b* value; and the first L* value is different from the second L*value, the first a* value is different from the second a* value, the first b* value is different from the second b* value, or combinations of these; and wherein L*, a*, and b* values are determined using a CM-700d handheld spectrophotometer from Konica Minolta.

8. The display cover glass of claim 1, further comprising a semi-transparent antireflective (STAR) coating applied to an A surface of the display cover glass, the STAR coating having a transmittance (Tx) of greater than or equal to 60%.

9. A display assembly comprising the display cover glass of claim 1, a first display unit bonded directly to the B surface of the display cover glass in the first visual area, and a second display unit bonded directly to the B surface of the display cover glass in the second visual area.

10. The display assembly of claim 9, wherein:the first BM area is associated with the first display unit and the second BM area is associated with the second display unit, which has a reflected color different from the first display unit when both display units are turned off; the color of the first ink matches the reflected color of the first display unit when the first display unit is turned off; andthe color of the second ink matches the reflected color of the second display unit when the second display unit is turned off.

11. The display assembly of claim 9, wherein, when the first display unit, the second display unit, or both are powered on, the first display unit, the second display unit, or both have a brightness of from about 500 candelas / m2to about 2,500 candelas / m2, or from about 1,000 candelas / m2to about 2,000 candelas / m2.Attorney Docket No. SP25-139PCT12. A method of making a display cover glass, the method comprising:providing a cover glass having an A surface and a B surface;applying a first ink to a first black matrix (BM) area of the cover glass, wherein the first BM area surrounds a first visual area;applying a second ink to a second BM area of the cover glass, wherein the second BM area surrounds a second visual area, wherein the second ink has a color different from a color of the first ink; andapplying the first ink and the second ink to the cover glass in a transition region disposed between the first BM area and the second BM area to produce the display cover glass, wherein the transition region has a gradient in a color density distribution of the first ink, the second ink, or both between the first BM area and the second BM area.

13. The method of claim 12, further comprising varying a spatial density distribution of the first ink, the second ink, or both in the transition region, wherein the spatial density distribution is defined as a coverage area of an ink per unit area of the B surface of the display cover glass.

14. The method of claim 13, wherein varying the spatial density distribution of the first ink, the second ink, or both in the transition region comprises applying the first ink, the second ink, or both in a halftone pattern comprising a plurality of dots and varying a size of the plurality of dots, a center-to-center spacing of the plurality of dots, or both based on position of each of the plurality of dots within the transition region.

15. The method of claim 12, the method comprising:printing a first pattern of the first ink on a B surface of the display cover glass, wherein the first pattern includes a first solid pattern in the first BM area and a halftone pattern in the transition region;after printing the first pattern of the first ink, printing a second pattern of the second ink onto the B surface of the display cover glass, wherein the second pattern includes a second solid pattern covering the second BM area and the transition region;wherein:Attorney Docket No. SP25-139PCTin the transition region, the second pattern of the second ink overlaps the halftone pattern of the first ink; andthe overlap of the second pattern of the second ink on top of the halftone pattern of the first ink in the transition region provides a gradient in color between the first ink in the first BM area and the second ink in the second BM area.

16. The method of claim 12, the method comprising:printing a first pattern of the first ink on a B surface of the display cover glass, wherein the first pattern has a first solid pattern in the first BM area and a first halftone pattern in the transition region;after printing the first pattern of the first ink, printing a second pattern of the second ink onto the B surface of the display cover glass, where the second pattern includes a second solid pattern in the second BM area and a second halftone pattern in the transition region, wherein:in the transition region, the second halftone pattern of the second ink overlaps the first halftone area of the first ink; andthe overlap of the second halftone pattern of the second ink on top of the first halftone pattern of the first ink in the transition region provides a gradient in color between the first ink in the first BM area and the second ink in the second BM area.

17. The method of claim 12, wherein the first ink has a first L* value, a first a* value, and a first b* value; the second ink has a second L* value, a second a* value, and a second b* value; and the first L* value is different from the second L*value, the first a* value is different from the second a* value, the first b* value is different from the second b* value, or combinations of these; and wherein L*, a*, and b* values are determined using a CM-700d handheld spectrophotometer from Konica Minolta.

18. The method of claim 12, further comprising applying a semi-transparent antireflective (STAR) coating to an A surface of the display cover glass, the STAR coating having a transmittance (Tx) of greater than or equal to 60%.Attorney Docket No. SP25-139PCT19. A method of making a display assembly, the method comprising:preparing a display cover glass according to the method of claim 12; coupling a first display unit to the B surface of the display cover glass in the first visual area; andcoupling a second display unit to the B surface of the display cover glass in the second visual area.

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