TW202001310A - Glass articles including elongate polymeric microstructures - Google Patents

Abstract

Light guide plates are disclosed that can be used in a backlight unit suitable for use as an illuminator for liquid crystal display devices and methods for their manufacture are disclosed. The light guide plates can comprise a plurality of elongate polymeric microstructures on a major surface of a glass substrate. The microstructures can be polymeric multilayer microstructures to provide lenticular features.

Description

Glass object containing elongated polymer microstructure

The present invention relates generally to glass objects that can be used as light guide plates in backlight units for illuminating liquid crystal display devices, and in particular, glass objects that can be used as light guide plates in backlight units configured for one-dimensional dimming.

Although the popularity of organic light emitting diode (OLED) display devices is increasing, the cost of producing such display devices is still high, and liquid crystal display (LCD) devices still include large sales Some display devices, in particular, large panel size devices such as televisions and other large format devices such as commercial signs. Unlike the OLED display panel, the LCD panel itself does not emit light, and therefore relies on a backlight unit (BLU) including a light guide plate (LGP) located behind the LCD panel to provide transmitted light to the LCD panel. The light from the BLU illuminates the LCD panel and the LCD panel acts as a light valve that selectively allows light to pass through the pixels of the LCD panel or be blocked, thereby forming a visible image.

Without amplification, the natural contrast ratio that can be achieved with an LCD display is the ratio of the brightest part of the image to the darkest part of the image. The simplest contrast enhancement is performed by increasing the overall illumination of bright images and reducing the overall illumination of dark images. Unfortunately, this results in soft and bright parts in the dark image, and the dark parts in the bright image are washed away. To overcome this limitation, manufacturers can incorporate active area dimming of the image, where the illumination in a predefined area of the display can visually display the image in the display relative to other areas of the display panel. When the light source is located directly behind an LCD panel such as a two-dimensional array of LEDs, such area dimming can be relatively easily incorporated. Regional dimming is more difficult to incorporate with edge lighting BLU, where the array of LEDs is arranged along the edge of the light guide plate incorporated into the BLU.

A typical light guide plate also has a polymer light guide such as polymethyl methacrylate (PMMA). PMMA is easy to form and can be molded or processed to facilitate area dimming. However, PMMA can suffer from thermal degradation, including a relatively large coefficient of thermal expansion, suffers from moisture absorption and is easily deformed. On the other hand, glass is dimensionally stable (including a relatively low coefficient of thermal expansion) and can be produced as a huge sheet suitable for increasing the popularity of large thin TVs.

Accordingly, it will be desirable to produce BLUs that include thin glass light guide plates that can facilitate area dimming. In addition, it would be desirable to provide glass LGPs with improved regional dimming efficiency, for example, glass LGPs with microstructures on at least one surface. These microstructures can reduce color shift and solve conventional reliability problems. It may also be advantageous to provide a backlight having a thickness similar to the thickness of the edge-illuminated BLU, while also providing an area dimming capability similar to that of the back-illuminated BLU.

The first aspect of the present invention relates to a light guide plate including: a glass substrate including an edge surface and two main surfaces; and a plurality of at least one of the main surfaces Elongated polymer multilayer microstructures, each elongated multilayer microstructure has a maximum height H and a width W measured at one-half (H/2) of the maximum height, and is further included in a range of about 0.1 to about 10 One of the aspect ratio W/H.

The second aspect of the present invention relates to a light guide plate including: a glass substrate including an edge surface and at least two main surfaces; and a plurality on at least one of the main surfaces Elongated polymer microstructures, each elongated polymer microstructure including a surface tilt angle of less than 15 degrees, and wherein the surface tilt angle is defined by an angle formed between: parallel to the glass substrate A line of light-emitting surfaces, and a line extending between a first uppermost surface of one of the elongated polymer microstructures at a maximum height H _{1 and} a second uppermost surface of the elongated polymer microstructure at a minimum height H ₂ .

The third aspect of the present invention relates to a method for manufacturing a light guide plate. The method includes the following steps: depositing a first layer of curable liquid on a main surface of a glass substrate as a first of the elongated liquid beads An array; at least partially radiation curing the first layer of curable liquid to provide an array of at least partially cured elongated microstructures separated by a distance S; depositing a first on the first array of at least partially cured elongated beads Two layers of curable liquid to serve as a second array of elongated liquid beads; at least partially radiation curing the second layer of curable liquid to provide at least partially cured a two-layer array of elongated microstructures; and at least partially cured An additional layer of curable liquid is optionally formed on the bilayer array of elongated microstructures to provide a multilayer array of n layers of elongated polymer multilayer microstructures, where n is in the range of 2-10.

The fourth aspect of the present invention relates to a method of forming a light guide plate. The method includes the following steps: depositing a curable liquid on a main surface of a glass substrate to provide a first curable liquid separated by an extended interval An array of layers; at least partially curing the array of elongated spaced apart curable liquid layers to form an array of spaced apart at least partially cured polymer layers; spaced apart at least partially cured polymer layers Depositing additional curable liquid on the array to form an array of second spaced apart curable liquid layers; at least partially curing the array of second spaced apart curable liquid layers to form at least partially cured An array of elongated polymer multilayer microstructures; and optionally forming an additional array of at least partially cured elongated polymer microstructures on the array of at least partially cured elongated polymer multilayer microstructures so that the at least partially cured elongated The array of polymer multilayer microstructures contains n layers, where n is in the range of 2 to 10.

Additional features of the embodiments disclosed herein will be described in subsequent embodiments, and will be partially clear from the description to those skilled in the art or recognized by practice of the embodiments described herein, including subsequent Detailed description, patent application scope and drawings.

The drawings are included to provide further understanding, and such drawings are incorporated into and constitute a part of this specification. The drawings illustrate various embodiments of the present invention, and together with the description serve to explain the principles and operation of the present invention.

Reference is now made in detail to the embodiments of the present invention, examples of which are illustrated in the drawings. Wherever possible, the same element symbols will be used throughout the drawings to refer to the same or similar parts. However, the present invention can be embodied in many different forms and should not be interpreted as being limited to the embodiments set forth herein.

The aspect of the present invention relates to a light guide plate including: a glass substrate including an edge surface and two main surfaces; and a plurality of elongated polymers on at least one of the main surfaces Multi-layer microstructures, each elongated multi-layer microstructure has a maximum height H and a width W measured at one-half (H/2) of the maximum height, and further includes about 0.1 to about 10, about 2 to about 9, about An aspect ratio W/H in the range of 2 to about 8, about 2 to about 7, or about 2.5 to about 6. In some embodiments, each elongated polymer multilayer microstructure includes at least two layers, at least three layers, at least four layers, at least five layers, at least six layers, at least seven layers, at least eight layers, at least nine layers, or at least ten layers . In some embodiments, each of the layers is at least partially a partially cured layer. In one or more embodiments, the height H of each of the plurality of elongated polymer microstructures does not exceed 100 microns (μm), for example, in the range of about 5 μm to about 100 μm. In some embodiments, there is a first spacing S in the first direction between two adjacent elongated polymer microstructures, the first spacing being between about 0.01*W to about 4*W or about 0.01*W to about 3*W or about 0.01*W to about 2.5*W or about 0.01*W to about 2*W or about 0.01*W to about 1.5*W or about 0.01*W to about 1*W.

In some embodiments, the first interval S is the same between all adjacent elongated polymer microstructures of the plurality of elongated polymer microstructures. In an alternative embodiment, the first interval S between a pair of two adjacent elongated polymer microstructures is different from the first interval between another pair of adjacent elongated polymer microstructures. In one or more embodiments, there is a second interval S2 in a second direction orthogonal to the first direction between two adjacent elongated polymer microstructures, the second interval being between about 10 μm and about 5000 Within the range of μm. In some embodiments, the second interval S2 is the same between all adjacent elongated polymer microstructures of the plurality of elongated polymer microstructures. In an alternative embodiment, the second interval S2 between a pair of two adjacent elongated polymer microstructures is different from the second interval S2 between another pair of adjacent elongated polymer microstructures.

In one or more embodiments, at least one of the plurality of elongated polymer multilayer microstructures further includes a length L, and wherein the other of the plurality of elongated polymer multilayer microstructures has a different One length L2.

In some embodiments, there is an inclination angle of the end surface of at least one of the plurality of microstructures, the inclination angle is less than about 15 degrees.

In one or more embodiments, the refractive index difference between the substrate and the plurality of microstructures is less than 10%.

In some embodiments, based on the mole% oxide, the glass substrate includes: 50 to 90 mole% SiO ₂ , 0 to 20 mole% Al ₂ O ₃ , 0 to 20 mole% B ₂ O ₃ , and 0 to 25 mol% R _x O, where x is 2, and R is selected from Li, Na, K, Rb, Cs, and combinations thereof, or where x is 1, and R is selected from Zn, Mg, Ca, Sr, Ba and their combinations.

In some embodiments, the thickness d _{1 of} the glass substrate is in the range of about 0.1 millimeter (mm) to about 3 mm. In one or more embodiments, the polymer film includes a UV-curable or heat-curable polymer. In some embodiments, the polymer film is microreplicated, screen printed, inkjet printed, laser bonded, printed, or grown onto the light emitting surface of the glass substrate.

One or more embodiments include a light guide plate including: a glass substrate having an edge surface and a light emitting surface; a multilayer polymer film including the multilayer polymer film disposed on the glass substrate The plurality of microstructures on the light-emitting surface, and the combined light attenuation α′ of less than about 5 dB/m for wavelengths in the range of about 420 to 750 nm.

Another aspect of the present invention relates to a light guide plate including: a glass substrate including an edge surface and a light emitting surface; and a plurality of elongated polymer microstructures, the plurality of elongated polymer microstructures Each of the structures includes a surface tilt angle of less than 15 degrees, less than 10 degrees, less than 4 degrees, or less than 2 degrees. The surface tilt angle is defined by an angle formed between: a line parallel to the light-emitting surface of the glass substrate, and a first uppermost surface at one of the elongated polymer microstructures at a maximum height H ₁ A line extending between the second uppermost surface of one of the elongated polymer microstructures at the minimum height H ₂ .

In some embodiments, the elongated polymer microstructures include multiple layers, and thus are elongated polymer multilayer microstructures. In certain embodiments, the elongated polymer multilayer microstructure has a surface tilt angle of less than 15 degrees, less than 10 degrees, less than 4 degrees, or less than 2 degrees, and each elongated polymer multilayer microstructure has a height H1 and Width W, where the aspect ratio is expressed as W/H and is in the range of about 0.1 to about 10, about 2 to about 9, about 2 to about 8, about 2 to about 7, or about 2.5 to about 6.

Other embodiments of the present invention include a method of manufacturing a light guide plate including a multilayer polymer film including a plurality of microstructures disposed on a light emitting surface of the glass substrate. An additional embodiment of the present invention relates to a light guide assembly including a light guide plate, the light guide plate comprising: a glass substrate having an edge surface and a light emitting surface; a multilayer polymer film, the multilayer polymer film Including a plurality of elongated microstructures disposed on a light emitting surface of the glass substrate; and at least one light source, the at least one light source is optically coupled to the edge surface of the glass substrate.

This article also discloses various devices including these light guides, such as displays, lamps and electronic devices, for example to name a few: TVs, computers, telephones, tablet devices and other display panels, lighting fixtures, solid state lamps, billboards and other buildings Elements.

Various embodiments of the present invention will now be discussed with reference to the drawings, which illustrate exemplary embodiments of microstructure arrays and light guide plates. The following general description is intended to provide an overview of the claimed device, and various aspects will be discussed more specifically throughout the present invention with reference to the non-limiting embodiments depicted, and within the context of the present invention, such embodiments are interchangeable with each other.

In FIG. 1, an exemplary LCD display device 10 is shown. The LCD display device includes an LCD display panel 12 formed by a first substrate 14 and a second substrate 16 bonded by an adhesive material 18. The adhesive material is located between the first substrate and the second substrate and surrounds a peripheral edge portion of the first and second substrates. The first and second substrates 14, 16 and the adhesive material 18 form a gap 20 containing a liquid crystal material therebetween. Spacers (not shown) can also be used at various locations within the gap to maintain a uniform gap in the gap. The first substrate 14 may include a color filter material. Accordingly, the first substrate 14 may be referred to as a color filter substrate. On the other hand, the second substrate 16 includes a thin film transistor (TFT) for controlling the polarization state of the liquid crystal material, and may be referred to as a backplane. The LCD panel 12 may further include one or more polarizing filters 22 on its surface.

The LCD display device 10 further includes a BLU 24 configured to illuminate the LCD panel 12 from the rear, that is, from the back panel side of the LCD panel. In some embodiments, the BLU may be spaced apart from the LCD panel, although in other embodiments, the BLU may be in contact with or coupled to the LCD panel, such as using a transparent adhesive. The BLU 24 includes a glass light guide plate (LGP) 26 formed of a glass substrate 28 as a light guide. The glass substrate 28 includes a first main surface 30, a second main surface 32, and the first main surface and the second A plurality of edge surfaces extending between the main surfaces. In an embodiment, the glass substrate 28 may be a parallelogram such as a square or a rectangle, which includes four edge surfaces 34a, 34b extending between the first main surface and the second main surface as shown in FIG. 2 , 34c and 34d, these edge surfaces define the XY plane of the glass substrate 28, as shown by the XYZ coordinates. For example, the edge surface 34a may be opposed to the edge surface 34c, and the edge surface 34b may be positioned opposite to the edge surface 34d. The edge surface 34a may be parallel to the opposed edge surface 34c, and the edge surface 34b may be parallel to the opposed edge surface 34d. The edge surfaces 34a and 34c may be orthogonal to the edge surfaces 34b and 34d. The edge surfaces 34a to 34d may be flat and orthogonal or substantially orthogonal (e.g., 90 +/- 1 degree, such as 90 +/- 0.1 degrees) to the main surfaces 30, 32, although in other embodiments, The edge surfaces may include chamfers, such as orthogonal or substantially orthogonal to the main surfaces 30, 32 and joined to the flat central portion of the first and second main surfaces by two adjacent inclined surface portions.

The first and/or second major surfaces 30, 32 may be included in the range of about 0.1 nanometer (nm) to about 0.6 nm, such as less than about 0.6 nm, less than about 0.5 nm, less than about 0.4 nm, less than about 0.3 nm , An average roughness (Ra) of less than about 0.2 nm or less than about 0.1 nm. The average roughness (Ra) of the edge surfaces may be equal to or less than about 0.05 microns (μm), for example, in the range of about 0.005 microns to about 0.05 microns.

The main surface roughness of the aforementioned level can be achieved, for example, by using a fusion drawing process or a float glass process, followed by polishing. The surface roughness can be obtained, for example, by atomic force microscopy using a commercial system (such as a commercial system manufactured by Zygo), white light interferometry, or by laser confocal microscopy using a commercial system (such as a commercial system provided by Keyence) Measure. The scattering from the surface can be measured by preparing a series of samples except for the surface roughness, and then measuring the internal transmittance of each sample. The difference in internal light transmittance between samples can be attributed to the scattering loss caused by the rough surface. Edge roughness can be achieved by grinding and/or polishing.

The glass substrate 28 further includes a maximum glass substrate thickness t in a direction orthogonal to the first main surface 30 and the second main surface 32. In some embodiments, the thickness t of the glass substrate may be equal to or less than about 3 mm, for example, equal to or less than about 2 mm or equal to or less than about 1 mm, although in other embodiments, the thickness t of the glass substrate may range from about 0.1 mm to In the range of about 3 mm, for example in the range of about 0.1 mm to about 2.5 mm, in the range of about 0.3 mm to about 2.1 mm, in the range of about 0.5 mm to about 2.1 mm, in the range of about 0.6 mm to about 2.1 mm range or in the range of about 0.6 mm to about 1.1 mm, including all ranges and subranges therebetween.

In various embodiments, the glass composition of the glass substrate 28 may include between 60 and 80 mol% SiO ₂ , between 0 and 20 mol% Al ₂ O ₃ and between 0 and 15 mol% B ₂ O _{3 in} between, and contains an iron (Fe) concentration of less than about 50 ppm. In some embodiments, less than 25 ppm of Fe may be present, or in some embodiments, the Fe concentration may be about 20 ppm or less. In various embodiments, the thermal conductivity of the glass substrate 28 may be greater than 0.5 W/m/K, for example, in the range of about 0.5 to about 0.8 W/m/K. In additional embodiments, the glass substrate 28 may be formed by polishing float glass, a fusion drawing process, a slit drawing process, a redrawing process, or another suitable glass substrate forming process.

In some embodiments, the glass substrate 28 comprises SiO ₂ in the range of about 65.79 mol% to about 78.17 mol%, Al ₂ O ₃ in the range of about 2.94 mol% to about 12.12 mol%, at 0 B ₂ O ₃ in the range of mole% to about 11.16 mole %, Li ₂ O in the range of 0 mole% to about 2.06 mole %, and in the range of about 3.52 mole% to about 13.25 mole% Na ₂ O, K ₂ O in the range of 0 mol% to about 4.83 mol%, ZnO in the range of 0 mol% to about 3.01 mol%, in the range of about 0 mol% to about 8.72 mol% MgO in the range, CaO in the range of about 0 mol% to about 4.24 mol%, SrO in the range of about 0 mol% to about 6.17 mol%, in the range of about 0 mol% to about 4.3 mol BaO in the range of% and SnO _{2 in the} range of about 0.07 mol% to about 0.11 mol%. In some embodiments, the glass substrate may exhibit a color shift of less than about 0.008, such as less than about 0.005. In some embodiments, the glass substrate includes R _x O/Al ₂ O _{3 in the} range of about 0.95 to about 3.23, where R is any one or more of Li, Na, K, Rb, and Cs, and x Is 2. In some embodiments, the glass substrate includes R _x O/Al ₂ O ₃ between 1.18 and 5.68, where R is any one or more of Li, Na, K, Rb, and Cs and is 2, Or Zn, Mg, Ca, Sr or Ba and x is 1. In some embodiments, the glass substrate includes R _x O-Al ₂ O ₃ -MgO in the range of about -4.25 to about 4.0, wherein R is any one or more of Li, Na, K, Rb, and Cs And x is 2.

In other embodiments, the glass substrate may include ZnO in the range of about 0.1 mol% to about 3.0 mol%, TiO ₂ in the range of about 0.1 mol% to about 1.0 mol%, in about 0.1 mol% V ₂ O ₃ in the range of% ear to about 1.0 mol %, Nb ₂ O ₅ in the range of about 0.1 mole% to about 1.0 mol %, in the range of about 0.1 mol% to about 1.0 mol% MnO, ZrO ₂ in the range of about 0.1 mol% to about 1.0 mol%, As ₂ O ₃ in the range of about 0.1 mol% to about 1.0 mol%, in the range of about 0.1 mol% to about 1.0 SnO ₂ in the range of mol %, MoO ₃ in the range of about 0.1 mol% to about 1.0 mol %, Sb ₂ O ₃ in the range of about 0.1 mol% to about 1.0 mol %, or about 0.1 CeO _{2 in the} range of mole% to about 1.0 mole %. In additional embodiments, the glass substrate may include one or a combination of any of the following from 0.1 mol% to no more than about 3.0 mol%: ZnO, TiO ₂ , V ₂ O ₃ , Nb ₂ O ₅ , MnO, ZrO ₂ , As ₂ O ₃ , SnO ₂ , MoO ₃ , Sb ₂ O ₃ and CeO ₂ .

However, it should be understood that the embodiments described herein are not limited by the glass composition, and the foregoing combination embodiments are non-limiting in this regard.

According to the embodiments described herein, the BLU 24 further includes an array of light emitting diodes (light emitting diodes) arranged along at least one edge surface (light incident edge surface) (eg, edge surface 34a) of the glass substrate 28; LED) 36. It should be noted that although the embodiment depicted in FIG. 1 shows a single edge surface 34a where light enters, the claimed subject matter should not have this limitation because any one of the edges of the exemplary glass substrate 28 or A few can have light incident. For example, in some embodiments, both the edge surface 34a and its opposite edge surface 34c can have light incident. Additional embodiments may inject light at the edge surface 34b and its opposite edge surface 34d instead of or in addition to the edge surface 34a and/or its opposite edge surface 34c. The light incident surface can be configured to scatter light within an angle of less than 12.8 degrees transmission full width half maximum (FWHM).

In some embodiments, the LED 36 may be positioned at a distance δ of less than about 0.5 mm from the light incident edge surface (eg, edge surface 34a). According to one or more embodiments, the LED 36 may include a thickness or height less than or equal to the thickness t of the glass substrate 28 to provide effective optical coupling into the glass substrate.

The light emitted by the array of LEDs is incident through at least one edge surface 34a and guided in the glass substrate according to total internal reflection, and for example by extracting features on one or both main surfaces 30, 32 of the glass substrate 28 Extract to illuminate the LCD panel 12. These extracted features interrupt total internal reflection and cause light within the glass substrate 28 to propagate through one or both major surfaces 30, 32 and exit the glass substrate. Accordingly, the BLU 24 may further include a reflector plate 38 located behind the glass substrate 28 and opposite the LCD panel 12 to redirect light extracted from the back surface (eg, the main surface 32) of the glass substrate to the forward direction (Toward the LCD panel 12). Suitable light extraction features may include a rough surface on the glass substrate, which is produced by directly roughening a surface of the glass substrate or by coating the sheet with a suitable coating such as a diffusion film. In some embodiments, light extraction features may be obtained, for example, by printing reflective discrete areas (eg, white spots) with a suitable ink, such as UV curable ink, and drying and/or curing the ink. In some embodiments, a combination of the aforementioned extracted features may be used, or other extracted features known in the art may be used.

The BLU may further include one or more films or coatings (not shown) deposited on one main surface of the glass substrate, such as quantum dot films, diffusion films, and reflective polarizing films, or combinations thereof.

For example, one-dimensional (1D) dimming area dimming can be achieved by turning on selected LEDs 36 that illuminate the first area along at least one edge surface 34a of the glass substrate 28 when other LEDs 36 that illuminate the adjacent area are turned off. Conversely, 1D area dimming can be achieved by turning off selected LEDs that illuminate the first area when the LEDs that illuminate the adjacent area are turned on.

FIG. 2 shows a portion of an exemplary LGP 26 that includes a first sub-array 40a of LEDs disposed along the edge surface 34a of the glass substrate 28 and a second sub-array of LEDs disposed along the edge surface 34a of the glass substrate 28 An array 40b and a third sub-array 40c of LEDs 36 arranged along the edge surface 34a of the glass substrate 28. Three different regions of the glass substrate illuminated by the three sub-arrays are labeled A, B, and C, where region A is the middle region, and regions B and C are adjacent to region A. Regions A, B, and C are illuminated by LED sub-arrays 40a, 40b, and 40c, respectively. In the case where the LED of the sub-array 40a is in the "on" state and all the other LEDs of the other sub-arrays such as the sub-arrays 40b and 40c are in the "off" state, the regional dimming index LDI can be defined as 1-(B, Average brightness of area C)/(lightness of area A). A more comprehensive explanation for determining LDI can be found, for example, in Jung et al. "Local Dimming Design and Optimization for Edge-Type LED Backlight Unit" (SID 2011 Digest, In 2011, pages 1430 to 1432), it was found that the content of this article was incorporated into this article by full text citation.

It should be noted that the number of LEDs or even the number of sub-arrays in any one array or sub-array is at least a function of the size of the display device, and the number of LEDs depicted in Figure 2 is for illustration only and is not intended to be limiting Sexual. Accordingly, each sub-array may include a single LED or more than one LED, or a plurality of sub-arrays may be arranged in a manner necessary to illuminate a particular LCD panel, such as three sub-arrays, four sub-arrays, five sub-arrays, and so on. For example, a typical 55” (139.7 cm) LCD TV with 1D area dimming function may have 8 to 12 zones. The zone width is generally in the range of about 100 mm to about 150 mm, although in some embodiments, the zone width may be smaller. The length of the zone is approximately the same as the length of the glass substrate 28.

Referring now to FIGS. 3A to 3E showing various embodiments of the light guide plate, the light guide plate 26 includes a glass substrate 28 having a glass substrate thickness t and a plurality of polymer microstructures 70. In certain embodiments, the polymer microstructures 70 are polymer multilayer microstructures 70. As shown in FIG. 3A, the plurality of polymer multilayer microstructures 70 provide a plurality of rectangular or square channels 60 on one surface (eg, the first major surface 30) of the glass substrate, although in other embodiments, the plurality of channels 60 The channel may be formed in the second main surface 32, or in both the first main surface 30 and the second main surface 32. In some embodiments, light extraction features may be formed in one or both of the first major surface 30 and the second major surface 32. In some embodiments, each channel of the plurality of channels 60 is substantially parallel to an adjacent channel of the plurality of channels 60. Each polymer multilayer microstructure 70 includes a maximum height H and a width W defined at H/2 (half the height H of the polymer multilayer microstructure 70), the width is shown in FIGS. 3A to 3E Indicated by the line H/2. Each polymer multilayer microstructure 70 has a width W, and the adjacent polymer multilayer microstructure 70 is separated by a distance S at H/2 (at half of the maximum height H of the polymer multilayer microstructure 70). The thickness T of the light guide plate is defined by the thickness t of the glass substrate and the maximum height H of the polymer multilayer microstructure 70. The adjacent polymer multilayer microstructure 70 defines channels 60 that are separated by a distance S from the adjacent polymer multilayer microstructure.

One or more polymer multilayer microstructures 70 have a non-zero maximum height H. For example, H may be in the range of about 5 μm to about 300 μm, such as about 10 μm to about 250 μm, about 15 μm to about 200 μm, about 20 μm to about 150 μm, about 30 μm to about 100 μm , About 20 μm to about 90 μm, including all ranges and subranges therebetween, although depending on the cross-sectional shape of the polymer multilayer microstructure 70, other heights are also considered. In some embodiments, the width W may range from about 50 μm to about 1 mm, such as about 50 μm to about 500 μm, about 100 μm to about 400 μm, about 100 μm to about 300 μm, about 100 μm to About 250 μm, about 100 μm to about 200 μm, about 100 μm to about 190 μm, about 100 μm to about 180 μm, about 100 μm to about 175 μm, or about 100 μm to about 150 μm, including all ranges and in between The sub-range, although other widths are also considered, the cross-sectional shapes of the polymer multilayer microstructures 70. The polymer multilayer microstructure 70 may have a cross-sectional dimension W at H/2 (at half of the maximum depth H of each channel).

The polymer multilayer microstructures 70 may be periodic, and the period P=W+S, although in other embodiments, the polymer multilayer microstructures 70 may be non-periodic. The polymer multilayer microstructures 70 can have various cross-sectional shapes. For example, in the embodiment of FIG. 3A, one cross section of the polymer multilayer microstructure 70 has a rectangular shape, which is perpendicular to the longitudinal axis of each polymer multilayer microstructure 70 in the X-Y plane. In the embodiment of FIG. 3B, each polymer multilayer microstructure 70 has, for example, a curved cross-sectional shape such that each channel 60 has a circular cross-section such as a semi-circle, while in the embodiment of FIG. 3C Each polymer multilayer microstructure 70 includes a trapezoidal cross-sectional shape. In FIG. 3D, each polymer multilayer microstructure 70 includes a semi-circular lenticular lens on a glass substrate 28. In some embodiments, a polymer platform (not shown) may be located between the glass substrate 28 and each polymer multilayer microstructure 70. However, the cross-sectional shapes of FIGS. 3A to 3D are non-limiting, and the polymer multilayer microstructures 70 may include other shapes, or a combination of cross-sectional shapes, such as prism or prism. For example, in the embodiment shown in FIG. 3E, each polymer multilayer microstructure 70 includes a prism cross-sectional shape, and the prism can have a prism angle in the range of about 60º to about 120º θ, such as about 70º to about 110º, about 80º to about 100º, or about 90º, includes all ranges and subranges therebetween. In FIG. 3E, the polymer multilayer microstructures 70 are disposed on a polymer platform 72 having a polymer platform thickness t2, and the polymer platform is disposed on a glass substrate 28. The thickness T of the light guide plate in FIG. 3 is the sum of the thickness t of the glass substrate, the thickness t2 of the polymer platform, and the height H of the polymer multilayer microstructure 70. Other suitable cross-sectional shapes for the polymer multilayer microstructure 70 include semi-circular, semi-elliptical, parabolic, or other similar circular shapes. In addition, although FIGS. 3A to 3E illustrate a regular (or periodic) array, an irregular (or aperiodic) array may also be used. For example, Figure 3F is an SEM image of the microstructured surface of a non-periodic array of polymer multilayer prisms.

In some embodiments, the ratio W/H of each of the plurality of polymer multilayer microstructures 70 is in the range of about 0.1 to about 10, for example, about 2 to 9, about 2 to about 8 , About 2 to about 7, about 2.5 to about 6, or about 2.5 to about 5, including all ranges and subranges therebetween. In some embodiments, when W/H is greater than about 10, the polymer multilayer microstructures 70 may become ineffective for 1D area dimming. In some embodiments, when the W/H is less than about 0.1, the polymer multilayer microstructures 70 may be difficult to manufacture.

As used herein, the terms "microstructure", "microstructured" and variations thereof are intended to refer to surface relief features of a cured film formed from a resin composition, such features having at least one dimension (eg, height, Width, length, etc.), the at least one dimension is less than about 500 μm, such as less than about 400 μm, less than about 300 μm, less than about 200 μm, less than about 100 μm, less than about 50 μm or even smaller, for example at about 10 μm The range up to about 500 μm includes all ranges and subranges therebetween. In some embodiments, the cured film forms polymer microstructures, which in certain embodiments may have regular or irregular shapes, which may be the same or different in a given array. Although FIGS. 3A through 3E generally illustrate polymer multilayer microstructures 70 of the same size and shape that are evenly spaced at substantially the same pitch (eg, periodicity), it will be understood that it is not within a given array All polymer multilayer microstructures must have the same size and/or shape and/or spacing. Combinations of polymer multilayer microstructure shapes and/or sizes can be used, and these combinations can be configured in a periodic or aperiodic manner.

In addition, the size and/or shape of the polymer multilayer microstructures can vary depending on the desired light output and/or optical functionality of the LGP. For example, different polymer multilayer microstructure shapes can produce different regional dimming efficiencies, also known as local dimming index (LDI). By way of non-limiting example, a periodic array of multi-layer microstructures of 稜鏡 polymers can produce an LDI value of up to about 70%, while a periodic array of lentil lenses can produce an LDI value of up to about 83%. The microstructure size and/or shape and/or spacing can be changed to achieve different LDI values. Different polymer multilayer microstructure shapes can also provide additional optical functionality. For example, a prism array with a 90° prism angle can not only lead to more efficient area dimming, but also can partially focus light in a direction perpendicular to the prism ridge due to light recycling and redirection.

Each of the polymer microstructures shown in FIGS. 3A to 3F can be formed on a glass substrate to provide the light guide plate as described in relation to FIG. 4. Therefore, each of the structures described with respect to FIGS. 3A to 3F can serve as a lentil-like structure, lentil-like lens, or lentil-like feature effective for guiding light emitted through the main surface of the light guide plate. Therefore, the term "lentil-shaped" is not limited to a specific shape or a cross-sectional shape, but may include an elongated microstructure having a convex or concave curved cross-sectional shape, such as the shape shown in FIGS. 3B and 3D, such as the 3A The square or rectangle shown in the figure, the trapezoid as shown in Figure 3C, or the triangle as shown in Figure 3E.

Referring now to FIG. 4, there is shown a light guide plate 26 including at least one light source 40 that can be optically coupled to an edge surface 29 of a glass substrate 28, for example, positioned adjacent to the edge surface 29. As used herein, the term "optical coupling" is intended to indicate that the light source is located at the edge of the LGP in order to introduce light into the LGP. The light source can be optically coupled to the LGP, even if the light source is not in physical contact with the LGP. Additional light sources (not shown) can also be optically coupled to other edge surfaces of the LGP, such as adjacent or opposed edge surfaces.

Light incident into the LGP from the light source 40 can propagate along the length L of the LGP as indicated by arrow 161 due to total internal reflection (TIR) until the light strikes the interface at an incident angle less than the critical angle . TIR is that light propagating in a first material (for example, glass, plastic, etc.) containing a first refractive index can pass through an interface with a second material (for example, air, etc.) containing a second refractive index less than the first refractive index The phenomenon of total reflection. TIR can be explained using Snell's law:

， 該定律描述折射率不同之兩種材料之間的界面處的光折射。根據斯涅耳定律，n₁ 係第一材料之折射率，n₂ 係第二材料之折射率，θ_i 係界面處入射的光相對於界面之法線之角度(入射角)，且θ_r 係折射光相對於法線的折射角。當折射角(θ_r )為90º，例如，sin(θ_r ) = 1時，斯涅耳定律可表達為：(1)

This law describes the refraction of light at the interface between two materials with different refractive indices. According to Snell's law, n ₁ is the refractive index of the first material, n ₂ is the refractive index of the second material, θ _i is the angle (incident angle) of light incident at the interface relative to the normal of the interface, and θ _r The angle of refraction of the refracted light relative to the normal. When the angle of refraction (θ _r ) is 90º, for example, sin(θ _r ) = 1, Snell's law can be expressed as:

(2)

The incident angle θi under these conditions may also be referred to as the critical angle θ _c . Light with an incident angle greater than the critical angle (θ _i > θ _c ) will be totally internally reflected in the first material, while light with an incident angle equal to or less than the critical angle (θ _i > θ _c ) will mostly One material transmits.

In the case of an exemplary interface between air (n ₁ =1) and glass (n ₂ =1.5), the critical angle (θ _c ) can be calculated as 41º. Therefore, if the light propagating in the glass impinges on the air-glass interface at an angle of incidence greater than 41º, all the incident light will be reflected from the interface at an angle equal to the angle of incidence. If the reflected light hits a second interface containing the same refractive index relationship as the first interface, the light incident on the second interface will be reflected again at a reflection angle equal to the incident angle.

In some embodiments, the polymer platform 72 may be disposed on one of the major surfaces of the glass substrate 28 (such as the light emitting surface 160 opposite the second major surface 170). The array of microstructures 70 can be shown as indicated by the dashed arrow 162 along with other optical films (eg, a reflector film and one or more diffuser films, not shown) disposed on the surfaces 160 and 170 of the LGP The light transmission is directed in the forward direction (for example, towards the user). In some embodiments, the light source 40 may be a Lambertian light source, such as a light emitting diode (LED). The light from the LEDs can quickly expand within the LGP, which can be a challenge to achieve area dimming (eg, by turning off one or more LEDs). However, by providing one or more microstructures extending on the surface of the LGP in the direction of light propagation (as indicated by arrow 161 in Figure 4), it may be possible to limit the spread of light so that each LED source Only effectively illuminate the narrow strip of LGP. The illuminated strip may, for example, extend from the starting point at the LED to a similar end point on the opposite edge. Thus, using various microstructure configurations, it may be possible to achieve one-dimensional (1D) area dimming of at least a portion of the LGP in a relatively efficient manner.

According to one or more embodiments, the light guide plate is manufactured by coating a radiation curable material, such as an elongated polymer microstructure that allows patterning on the surface of the glass substrate to provide sufficient optics for the glass LGP Resin composition with properties and reliability in high temperature and humidity and mechanical strength. As used herein, "radiation curable" refers to a material that uses light energy or heat energy provided by ultraviolet, infrared, or visible light to initiate a curing reaction. In some embodiments, the light emitted by the radiation source reacts with the photoinitiator in the resin composition to form a polymer microstructure. Examples of radiation curable materials include acrylates (eg, methacrylates) and epoxy. In one or more embodiments, a method is provided that allows patterning to provide a plurality of multilayer microstructures, at least one microstructure having a maximum height H, measured at one-half (H/2) of the maximum height A width W and a ratio W/H in the range of about 0.1 to about 10. The ratio W/H may also be referred to as the aspect ratio of the elongated polymer microstructure.

Referring now to FIG. 5, one or more embodiments provide an elongated polymer microstructure that is a polymer multilayer microstructure 70 disposed on a glass substrate 28. FIG. 5 shows an enlarged cross-sectional view of a single polymer multilayer microstructure 70 on a glass substrate 28 according to an embodiment of the present invention. Although the embodiment shown in FIG. 5 has a semicircular cross-section similar to the polymer multilayer microstructure 70 shown in FIG. 3D, it will be understood that the polymer multilayer microstructures may be suitable for use in light guide plates Any cross-sectional shape, such as those shown in FIGS. 3A to 3E. In FIG. 5, the polymer multilayer microstructure 70 includes a first polymer layer 70a disposed on the glass substrate 28, a second polymer layer 70b disposed on the first polymer layer 70a, and a second polymer The third polymer layer 70c on layer 70b. The number "n" of individual polymer layers is not limited to the three layers 70a, 70b, and 70c shown in FIG. In one or more embodiments, the number "n" of individual layers may be in the range of 2 to 25, such as 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14 , 15, 16, 17, 18, 19 or 20. As will be described further below, an embodiment of the present invention provides a light guide plate including a glass substrate including a plurality of polymer multilayer microstructures, wherein the number of layers "n" is between 2 and 20 or between 2 and 15 or 2. To 10 or 2 to 5. In some embodiments, each of the individual layers is partially cured before depositing the next layer. In one or more embodiments, "partially cured" includes 20% to 80%, 20% to 70%, 20% to 60%, 20% to 50%, 20% to 40%, 40% to 60 %, 40% to 80%, 50% to 60%, 50% to 80% or 60% to 80% in the range of curing.

Referring now to FIG. 6A, an exemplary non-limiting cross-section of an embodiment of a polymer multilayer microstructure is schematically shown. In this case, the cross-section is a circular cross-section, where W, H, and θ are respectively The width, height and contact angle of the shape. Fig. 6B is a diagram of the contact angle varying with the aspect ratio W/H (width/height). Lentil-like optical design requires a low aspect ratio, at least W/H> 10. Generally speaking, according to one or more embodiments, the lower the value of W/H, the greater the limiting effect of the waveguide on light. According to some embodiments, the contact angle θ is instead greater than 45° corresponding to W/H>5. However, creating this structure by printing with a precursor liquid composition can be challenging. For this high contact angle value, the printed liquid line becomes unstable due to Rayleigh-Taylor instability and breaks down into droplets as depicted in Figures 7B and 7C.

Figure 7A shows stable, undisturbed, continuous elongated beads of material that can form the polymer microstructure 70. Figure 7B shows a disturbed liquid bead with a contact angle θ, which remains fixed at an equilibrium value when the contact line moves freely. Figure 7C shows liquid beads with a contact angle that depends on the deposition rate, but decreases to an equilibrium value at zero speed, and beads with a contact line that stops in a parallel state when the contact angle changes freely. For other details about the stability of liquid beads on a solid surface, see Schiaffeaino and Sonin's Formation and stability of liquid and molten beads on a solid surface (Formation and stability of liquid and molten beads on a solid surface) ( J. Fluid Mech. Vol. 343, pages 95 to 110 (1997)). Instability that proceeds faster than the coagulation mechanism will result in uneven beads.

It is determined that there are two ways to reduce bead instability. One method involves roughening the glass surface of the substrate used to form the light guide plate so that the contact lines remain fixed. However, this requires additional treatment for obtaining a rough glass surface. The determination of bead instability can be avoided by at least partially curing the deposited curable material to increase the viscosity of the material and prevent the instability from evolving during deposition. By sequentially depositing and at least partially curing the deposited individual layers, and then depositing and curing additional individual layers in the same manner, it was found that a plurality of multilayer microstructures can be formed, at least one of which has a maximum height H and a maximum height at the maximum height A width W measured at half (H/2), and included in about 0.1 to about 10, such as about 2 to 9, about 2 to about 8, about 2 to about 7, about 2.5 to about 6, or about 2.5 to The ratio W/H is within a range of about 5.

One or more embodiments of the present invention provide methods including the steps of: distributing by radiation (eg, ultraviolet (ultraviolet; UV) illumination, infrared (infrared) continuously, almost immediately or instantaneously after the liquid has been deposited IR) or thermal energy) at least partially curing one of the curable liquids. In one or more embodiments, "almost immediately after deposition" and "instantaneously after deposition" means that the curable liquid system is less than 30 seconds, less than 20 seconds, less than 10 seconds after depositing the curable liquid, Less than 5 seconds, less than 4 seconds, less than 3 seconds, less than 2 seconds, less than 0.9 seconds, less than 0.8 seconds, less than 0.7 seconds, less than 0.6 seconds, less than 0.5 seconds, less than 0.4 seconds, less than 0.3 seconds, less than 0.2 seconds, or less than 0.1 Seconds curing. The time to start curing after depositing the polymer liquid will depend on the viscosity of the liquid and the stability of the liquid on the glass panel, both of which can be determined experimentally. However, in general, the degree of curing and curing time should be selected to prevent the beads from becoming unstable.

One or more embodiments include a process of forming an elongated polymer microstructure that includes depositing a curable liquid (eg, optically clear UV curable ink) and curing the curable at least partially instantaneously after deposition liquid. In some embodiments, a continuous curable liquid dispenser and an instant radiation curing (eg, UV curing, IR curing, or thermal curing) process are used to continuously manufacture elongated polymer microstructures on a major surface of a glass substrate. In one or more embodiments, continuous formation of an elongated polymer microstructure is provided, which involves in-situ curing of the dispensable curable liquid, thereby fixing the contact line of the ink. "Contact line" refers to the contact line of the curable material deposited on the glass substrate. Additionally, in one or more embodiments, the method can be repeated more than once to create a microstructure containing multiple layers (referred to herein as an elongated polymer multilayer microstructure), thereby creating a The aspect ratio of light.

In a specific embodiment, a commercial continuous liquid dispenser (GPD Max series PCD3H available from GPD Global, Inc. (Grand Junction, Colorado)) is used to manufacture elongated polymer microstructures on glass and is useful in forming Lentil-like patterns are produced on the light guide plate of the desired aspect ratio for 1D dimming.

According to one or more embodiments, the continuous dispensing procedure avoids the formation of discrete droplets when the curable liquid is ejected from the dispenser. In some embodiments, the device includes a liquid dispenser and a cumulative radiation (eg, UV energy or thermal energy) curing system directly following the dispenser. This allows the curable liquid (eg, ink) to be at least partially cured after the curable liquid is dispensed on the glass surface, which in turn prevents dewetting of the ink. In some embodiments, in the absence of in-situ curing, the ink does not maintain a straight line, and a sinusoidal shape or even discrete droplets are generated due to Rayleigh-Purato instability.

In one or more embodiments, the elongated polymer microstructure and the elongated polymer multilayer microstructure can be formed using an inkjet printer with a curing head. For example, experiments were conducted to use commercial piezoelectric inkjet printers with a resolution of 1440 dpi and optically clear UV curable inks to form elongated polymer microstructures established on glass substrates using an inkjet printing process. The inkjet printer has a built-in LED UV curing system that cures the UV ink in each pass. In-situ solidification after each pass helps "fix" the droplet to the surface. According to some embodiments, in the first step, an image file with a microstructure line with a gap of 150 micrometers and a width of 150 micrometers is created by using the Adobe® Illustrator drawing software file and converting the file into a behind-the-scenes typesetting file. In the second step, a clear glass substrate measuring 8.5 inches by 11 inches was used as the substrate for printing. An optional silane layer is used to control the spread of inkjet drops on the glass surface. In the third step, inkjet printing of the optically clear UV ink is performed layer by layer, and curing is performed after each layer forms an elongated multilayer microstructure having various aspect ratios. The profilometer measurement was performed using Tencor P11 at a scan speed of 50 μm/sec, a sampling rate of 100 Hz, and a scan length of 8000 μm. The height of these elongated microstructures increased from 8 to 10 microns in a single layer to 18 microns in a double-layered microstructure. The three-layer inkjet printed elongated microstructure provides a height of 56 microns, and the four-layer inkjet printed elongated microstructure provides a height of 68 microns. The width of the elongated microstructure is calculated as 168 microns based on the measurement results of the same profilometer, resulting in a 3:1 aspect ratio of the elongated microstructure for three-layer inkjet printing and the elongated microstructure for four-layer inkjet printing Aspect ratio of 2:1. Three-layer and four-layer elongation produce 1D dimming effect.

The methods described herein allow the formation of lentil-like structures with a ground W/H ratio by performing multiple deposition and curing cycles. Figures 8A to 8C are scanning electron microscope (SEM) photographs of a top view (Figure 8A) and a cross-sectional view (Figures 8B and 8C) of the elongated polymer microstructure on the glass. Liquid nitrogen freeze fracture causes the lentil-like structures to delaminate from the glass surface. The structures shown in Figures 8A through 8C are manufactured using four deposition and curing cycles using GPD Max series PCD3H dispensers that utilize in-situ UV curing. Each lentil line is formed by four consecutive cycles. A close inspection of Figure 8C shows four discrete individual layers: the first layer 70a on the glass substrate, the second layer 70b on the first layer 70a, the third layer 70c on the second layer 70b, and the The fourth layer 70d on the third layer 70c. It is clear from Figure 8A that the lentil-like features are fairly straight, without any unstable appearance. These cross-sectional views show each of the four layer passes. The shape of the locking feature after each pass is cured. This allows these features to be established layer by layer to achieve extremely low W/H ratios. For example, in this case, width (W) = 170 μm, height (H) = 60 μm, and W/H = 2.8, this ratio is much lower than the desired maximum threshold of 5. The details of the curable liquid include optical ink Norland 68TH low viscosity, Norland 123TKHGA high viscosity and MPOSS nanosilica + 1 wt% 1173 (photoinitiator) + 2 wt% Texanol, MPOSS nanosilica + 1 wt% 1173 ( Photoinitiator) + 2 wt% Texanol + 2 wt% IPA and MPOSS Nanosilica + 1 wt% 1173 (photoinitiator) + 2 wt% IPA. PCD3H distributor parameters: 74.3rpm auger speed and 23mm/sec line distribution speed. After the last layer has been deposited, the polymer multilayer microstructure may be exposed to radiation to subject the polymer multilayer microstructure to additional curing to increase the degree of curing. The degree or percentage of cure of the polymer microstructure can be determined by infrared spectroscopy. In some embodiments, the degree or percentage of cure of the microstructure is determined by the dielectric properties of the associated resin or by the change in the refractive index of the microstructure.

Figures 9A and 9B show the use of in-situ UV curing using the GPD Max series PCD3H dispenser built on an 8-inch by 11-inch (20.3 cm by 27.9 cm) IRIS glass substrate obtained from Corning, Inc. (Corning, NY) The optical image of the lentil-like features. Four deposition and curing cycles are utilized. The ink used in this example is Norland Optical 68TH ink with a low viscosity of about 20,000 percent poise (cp). The lentil-shaped lines have a width of about 150 μm, and there is a separation gap of about 150 μm between the features. From these images, it can be clearly seen that well-defined lentil-like features can be produced on large substrates by this method.

Figures 10A and 10B show structures similar to those shown in Figures 9A and 9B, but these structures are made of high-viscosity Norland Optical 123TKHGA ink with a viscosity of approximately 500,000 percent poise. Lentil-like features were established on an 8-inch by 11-inch IRIS glass substrate available from Corning, Inc. (Corning, NY) using GPD Max series PCD3H dispensers using in-situ UV curing. Four deposition and curing cycles are utilized. In this case, the lenticular line width is about 200 μm and the separation gap is about 109 μm. The structures shown in Figures 9A and 9B and 10A and 10B show that it is possible to build structures using inks with varying viscosities ranging from about 20,000 cp to about 500,000 cp. Commercial inks with varying viscosities of about 20,000 cp to about 500,000 cp demonstrate the ability to dispense and establish lentil-like characteristics.

The peak-to-valley (PV) heights of the samples shown in Figures 9A, 9B, 10A, and 10B were measured using a Zygo instrument. In Figures 9A and 9B, the peak-to-valley heights are 48 microns, and in Figures 10A and 10B, the peak-to-valley heights are 58 microns. Depending on the viscosity of the material being dispensed, the surface tension of the substrate and the surface energy, the dispense parameters can be optimized to print the desired height in one pass or multiple cycles or passes.

The measurement of the optical limitations of the 280 mm x 215 mm bare glass samples and the samples manufactured according to Figures 9A to 9B and 10A to 10B was obtained using a CCD camera. The distributed sample contains a distribution height (H) of 50 to 58 microns, a distribution width (W) of 208 to 220 microns, and corresponding intervals (S) of 120, 92, and 80 microns. As can be seen from the images in Figures 11A to 11C, the bare glass sample (Figure 11A, top) shows no light limitations, and the laminated lentil-like structure (Figure 11A, bottom) shows the light limitations (collimation) And, using in-situ UV curing using the GPD Max series of PCD3H dispensers, all continuously dispersed samples showed similar effects (Figure 11B and Figure 11C). In addition, compared to the laminated samples at the output edge, all continuously dispersed samples made using GPD Max series PCD3H dispensers using in-situ UV curing showed no yellowing (color shift).

FIGS. 12A to 12B and FIG. 13 show the optical limitations expressed by a curve of normalized optical brightness that varies with position (mm). All samples showed a narrow light distribution similar to laminated lentil-shaped film. For all samples 250 mm away from the input edge, a local dimming index (LDI) greater than 80% for a 150 mm dimming width is achieved. In particular, in the sample WS01448 250 mm away from the input edge, a WS01448 LDI greater than 87% for a dimming width of 150 mm was achieved. In Figures 12A and 12B, the optical limit measurement results of sample WS0 1448 show the effect of 1D dimming. Bare glass and laminated lentil-shaped films are shown as controls. Continuous dispersion of lentil-like structures made with GPD Max series PCD3H dispensers using in-situ UV curing exhibits light limitations similar to laminated films, but has the added advantage of reduced optical color shift.

In Figure 13, the optical limit measurement results of samples WS01443, WS01449, WS01448, and WS01453 show the effect of 1D dimming. All continuously dispersed lentil-like structures manufactured using GPD Max series PCD3H dispensers using in-situ UV curing exhibit light limitations similar to laminated films, but with the added advantage of reduced optical color shift. For all samples 250 mm away from the input edge, an LDI greater than 80% for a width of 150 mm is achieved.

FIG. 14 is a block diagram of an embodiment of an apparatus 200 that can be used to continuously dispense and cure a curable liquid according to an embodiment of the present invention. The pump or fluid distribution device 216 is used to dispense a curable liquid that can be cured by radiation onto the glass substrate moving in the direction of arrow 234. In some embodiments, the pump or fluid distribution device 216 may be an auger pump or injection valve or other pneumatic or electrically controlled pump or valve, where the distribution structure depends on the fluid provided to the inlet of the distribution device. Other types of pumps or fluid distribution mechanisms can be used, such as time-pressure systems.

In some embodiments, the reservoir 215 stores a certain amount of curable liquid and supplies the curable liquid to the pump or fluid distribution device 216 via the fluid supply line 223. In one or more embodiments, the reservoir 215 may be a syringe, barrel, or larger container. In the embodiment shown in FIG. 14, the reservoir 215 is pressurized by an external air supply source 219 (eg, an air compressor) connected by an air supply line 218 regulated by a regulator valve 220, to Helps deliver fluid from the reservoir 215 to the inlet of a pump or fluid distribution device 216. In some embodiments, the reservoir may be pressurized by other mechanical devices, such as syringe mechanisms or hydraulic or electrical devices, such as motors or other electrical motion devices.

In one or more embodiments, the pressure sensor 217 can be used to detect the fluid pressure in the fluid supply line 223 between the reservoir 215 and the inlet to the pump or fluid distribution device 216. The pressure sensor 217 may be used to adjust the air pressure supplied to the reservoir 215. In some embodiments, the adjustment may be achieved by detecting changes in fluid pressure.

In some embodiments, the controller 221 receives the pressure reading 226 from the pressure sensor 217 in a digital or analog format. In the embodiment shown in FIG. 14, the controller 221 is configured as a feedback controller that uses the pressure sensor signal 226 as one of the feedback signals. The output of the controller 221 is applied to the control signal 227 (ie, control voltage) of the regulator valve 220 in the air pressure line 218 leading from the air supply source 219 to the reservoir 215, as shown in FIG. This feedback configuration (including the pressure sensor 217, the controller 221, and the regulator valve 220) responds to the fluid pressure measured by the pressure sensor 217 to effectively adjust the air pressure supplied to the reservoir 215 to maintain The predetermined fluid pressure in the fluid supply line, and thus helps maintain a constant input fluid pressure to the pump 216. In turn, this helps maintain more uniform properties of the fluid pattern dispensed by the pump or fluid dispensing device 216 at the dispenser tip or nozzle 228 (e.g., with respect to the first dispensing, droplet size, line width, and volume and weight repeatability ). Alternatively, if the reservoir 215 is pressurized by other means, the controller 221 may be used to modulate and adjust the pressure applied to the reservoir 215.

It should be understood that many different types of controllers can be used. In addition, any one of a wide variety of control algorithms can be used by the controller 221. For example, the controller 221 may be configured to adjust the air pressure to maintain a predetermined set point in the measured fluid pressure. This can be done with or without a dead band around the desired set point to avoid excessive adjustment of the air pressure to the reservoir 215. If the measured fluid pressure falls below a predetermined lower limit, the controller 221 adjusts the air supply pressure upward. If the measured fluid pressure rises above a predetermined upper limit, the controller 221 adjusts the air supply pressure downward. Proportional integral differential (proportional, integral, differential; PID) control algorithms can also be used to adjust the air supply pressure using fluid pressure as a feedback signal. .

The radiation source 230, such as an ultraviolet curing lamp, an infrared curing lamp, or a thermal energy source, is positioned adjacent to the dispenser tip or nozzle 228 so that when the substrate moves past the dispenser tip or nozzle 228, the curable polymer fluid is distributed on the glass substrate, and then After the liquid has been deposited, it is at least partially cured by radiation (for example, ultraviolet (UV) lighting or thermal energy) almost immediately or instantaneously. In one or more embodiments, "almost immediately after deposition" and "instantaneously after deposition" means that the curable liquid is less than 30 seconds, less than 20 seconds, less than 10 seconds, less than 5 after deposition of the curable liquid Seconds, less than 4 seconds, less than 3 seconds, less than 2 seconds, less than 0.9 seconds, less than 0.8 seconds, less than 0.7 seconds, less than 0.6 seconds, less than 0.5 seconds, less than 0.4 seconds, less than 0.3 seconds, less than 0.2 seconds or less than 0.1 seconds . The glass substrate can be placed on a suitable device to allow the substrate to move through the dispenser tip or nozzle 228 at a desired rate and then through the radiation source 230 so that the radiation source can at least partially cure the curable liquid. The radiation source 230 communicates with the controller 221, which sends a control signal via a hard-wired or wireless connection to turn the radiation source on and off and determine the radiation that will be emitted by the radiation source 230 to at least partially cure the curable liquid the amount.

Although a single distributor tip or nozzle 228 and radiation source 230 are shown in Figure 14, the illustrated embodiment is not limiting. For example, the apparatus shown in Figure 14 may include an array of dispenser tips or nozzles 228 to dispense multiple beads of curable liquid to form a plurality of elongated polymer microstructures on the glass substrate. For example, the device may include 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, or up to 25 dispenser tip nozzles 228 spaced apart to The polymer fluid is distributed on the glass substrate and forms a plurality of elongated polymer microstructures that can be used to form a light guide plate with 1D dimming characteristics. The radiation source 230 may be a 365 nm LED curing source having a width that can cure more than a single elongated polymer microstructure, such as a Dymax UV curing light source 38105-2000EC. In some embodiments, an array of radiation sources can be utilized, and the array of radiation sources 230 communicates with the controller 221. In some embodiments, the degree or percentage of curing of the elongated polymer microstructures can be monitored in situ. In other words, using a curing monitoring device (such as an infrared measurement system) or hardness measurement. In one or more embodiments, after the polymer multilayer microstructure has been formed by depositing multiple layers, the multilayer microstructure is further cured to increase the degree or percentage of cure of the polymer material.

In one or more embodiments, the elongated polymer microstructures are made of highly silicon-containing polymers (eg, greater than 15 wt.%, eg, 15 to 50 wt.% or 15-30 wt.%) These elongated polymer microstructures are highly transparent at visible wavelengths and provide lenticular lenses with lower color shift. In one or more embodiments regarding the light guide plate, the elongated polymer microstructures form a lentil lens with the following absorption loss: less than 10 dB/m in the visible wavelength range, or less than 5 dB in the visible wavelength range /m, or less than 2 dB/m in the visible wavelength range. One or more embodiments provide a light guide plate in which there is a refractive index difference of less than 10% between the glass substrate and the elongated polymer microstructures. In one or more embodiments, the elongated polymer microstructures have a pencil hardness greater than 4H, for example greater than 6H (as measured according to ASTM D3363-Standard Test Method for Film Hardness). In some embodiments, the elongated polymer microstructures exhibit good adhesion, for example, using a tape adhesion test to measure adhesion greater than 3 B or greater than 5 B, using ASTM D3359-according to the tape test for rated adhesion Standard test method for force-measuring adhesion. In one or more embodiments, the elongated polymer microstructures do not exhibit color shift under environmental aging, for example, based on the color shift exhibiting less than 10 dB/m or less than 5 dB/m in the visible wavelength range or Less than 2 dB/m absorption loss.

In some embodiments of the present invention, the elongated polymer microstructures are formed on a glass substrate using screen printing and curing individual layers to form a layer-by-layer multilayer microstructure. In a particular embodiment, the elongated polymer microstructures screen-printed on the glass substrate are 100 to 200 μm long and between two elongated polymer microstructures on the surface of the glass LGP to be in the range of 50 to 100 μm width The distance is separated. In one or more embodiments, screen printing and curing provide the ability to control the height, which allows the aspect ratio (defined as the width/height of the feature) to be changed from 3/1 to 10/1. Having higher features achieves a high aspect ratio (for example, closer to 2/1), allowing adjustment of zone widths as low as 20 mm. This minimizes the light propagation distance on the glass, reduces the color shift introduced by the lentil-like features, and helps reduce reliability issues caused by the CTE mismatch between the lentil-like material and the glass.

In some embodiments, an inorganic (glass) substrate with an organic (polymer) elongated microstructure structure reduces the different colors of light (R, G, B) that appear along the structure when different materials are used for the lentil-like structure ) The dispersion or speed changes. This enables the use of white LEDs. In addition, known polymer systems age or "yellowing" especially under continuous exposure to high light flux. This refractive index change can also be accompanied by an increased light absorption failure mode.

In some embodiments, the radiation curable materials selected for screen printing contain both inorganic and organic components. For example, Si is present in polymer materials with C, H, and O, where a silicon content greater than 15 wt.% and a carbon content less than 45 wt.% provide good results. Increase the silicon content in the experimental matrix by two methods: by (1) adding SiO ₂ nanoparticles (about 20 nm particles dispersed in the matrix, 0 to 30 wt.%); or by (2) Add organic siloxane or organosilicate chemistry in the form of polysilsesquioxane (RSiO _3/2 ) _n or polysilane (R ₂ SiO) _n .

Silsesquioxane-based silicate materials, where R is bonded to the organic group (or H) of silicon oxide via Si-C bond. The structure of silsesquioxane has been reported to be random, cage-like and partially cage-like (silsesquioxane, Suzuki et al., Chem. Rev. (1995, 95 (5), pages 1409 to 1430). In some embodiments, silsesquioxanes containing both cage (T8) and random structures are used, but many other structures are within the scope of the present invention. In some embodiments, the curable materials utilize UV photoinitiators Use the acrylate functionality of the R group to polymerize and/or crosslink, or use the R=hydroxy (-OH) functionality to use IR/heat to thermally polymerize and/or crosslink (Hybrid Plastics and Gelest).

In some embodiments, silicone materials can be used to form the elongated polymer microstructures. Silicones usually have two R groups attached to the silicon via Si-C bonds and are also called elastomers due to their viscoelastic properties. Silicones can be cured by thermal initiators, where high molecular weight linear chains are converted from a highly viscous plastic state to a mainly elastic state by crosslinking (suitable materials are available from Dow Corning and Gelest).

Silicone materials tend to have good thermal stability (heat and cold resistance, thermal shock resistance), oxidation, moisture, chemicals, and ultraviolet radiation stability due to the thermal and oxidation stability required for many advanced photonics and LED applications Properties, optical clarity, light transmittance, and low color shift under aging conditions. Figure 15 shows the color shift (difference chromaticity y value at 320 mm) of coated samples made with various materials having a thickness greater than 10 μm thickness. In particular, the color shift of the bar-coated sample on a 150 mm x 400 mm glass substrate was measured before and after aging. The aging conditions were 90% RH and 60°C for 4 days. The Y axis on the left depicts the color shift difference y at a distance of 320 mm. The Y-axis of RHS depicts the% increase in color shift with aging.

In one or more embodiments, the color shift as measured by using a spectroradiometer (PR670, Photo Research) before and after aging is less than 0.01/320 mm. Polymethyl methacrylate (PMMA) and NEA 121 (UV curable thiophene system (UV curing, Norland opticals)) were used as controls for comparison. The remaining materials shown in Figure 15 are silicon-containing materials. PMMA shows very low color shift, and NEA121 material shows quite obvious yellowing with aging.

Based on the color shift data, it was determined that the three silicon-containing polymers provided acceptable results: polydiphenylsiloxane (silicone, thermally cured at 120 to 250°C); UV-curable polyoctahedral silicon with silica Oxyalkylene (MPOSS nanometer, UV curing, 365 nm UV exposure) and polyphenylsilsesquioxane (thermal curing, curing at 150 to 420°C). All three silicon-containing materials exhibit low color shift. In addition, silicone provides a sealing device and protects the device from the adhesion, flexibility, and elasticity required by moisture, dust, and mechanical stress caused by shock and vibration.

According to one or more embodiments, an array of elongated polymer microstructures can be formed on a glass substrate to provide lentil-like structures formed as described below. The surface of the IRIS™ LGP board is shown in Figure 16, which shows an exemplary four-step procedure. It will be understood that the invention is not limited to a specific number of step sequences. In the first step, obtain a 1.1 mm thick, 8.5-inch by 11-inch IRIS™ glass substrate (available from Corning, Incorporated), and use standard glass cleaning procedures to use semi-clear cleaner, followed by deionized water to rinse the A glass substrate, and store the glass substrate under proper conditions before any subsequent processing steps. In the second step, select a curable material with suitable properties for the lenticular lens structure that forms the light guide plate for screen printing, and select a screen with the appropriate mesh size and percentage opening to achieve the desired printing characteristics Desired emulsion thickness. Next, the screen area is flooded with the polymer used in the printing step (an optical clear ink), and when sufficient wetting of the screen surface is achieved, varying printing speed (mm/sec), gap (mm) and Print pressure to apply this printing step. In this step, the wet thickness of the printed ink is controlled. In the third step, radiation is applied to the printed curable material, for example, a UV or post-bake step applied directly to the printed surface. Additional steps include repeating the second and third steps to achieve the desired wetted or cured thickness.

In order to increase the printing height of the elongated polymer microstructure, screen printing and evaluation of several mesh sizes (screen thickness and open area) using stainless steel materials with the printing characteristics of interest. The wet thickness listed in the table below is calculated using the formula provided by the material supplier. Wet thickness = screen thickness * opening area + emulsion thickness. In all cases, the printing width increases as the emulsion thickness increases, which affects the printing height. With an aspect ratio (W/H) of about 8.3, the maximum print height obtained is about 29 μm.

Table 1

Table 2

Examples A to O are based on MPOSS nano/Texanol/initiator formulations; Examples P to Q are based on MPOSS nano/Dowanol/initiator formulations

Perform rheological screening of curable materials. Perform shear sweep (viscosity change with shear rate 0 to 100 s ^-1 and time) and stable shear recovery measurement on the selected material to understand the viscosity behavior during screen printing.

Measure the shear sweep from 0.1/s to 100/s to avoid flow instability. The results are shown in Figure 17 and Figure 18. Figure 17 is a graph showing the stable shear sweep (shear viscosity versus shear rate) of screen printing inks containing Texanol solvent. Figure 18 is a graph showing the stable shear sweep (shear viscosity versus shear rate) of screen printing inks containing diethylene glycol monomethyl (Dowanol DPM™ solvent). The results show all solvent-free MPOSS nanosilica, MPOSS nanosilica + 1 wt% 1173 (photoinitiator) + 2 wt% Texanol, MPOSS nanosilica + 1 wt% 1173 (photoinitiator) + 2 wt% Texanol + 2 wt% IPA and MPOSS Nanosilica + 1 wt% 1173 (photoinitiator) + 2 wt% IPA is slightly sheared and reduced viscosity, and all show a small amount of thixotropic behavior. In addition, as the amount of Texanol (ester alcohol, Eastman Chemical Company) and/or isopropyl alcohol (IPA) increases, the viscosity decreases. In contrast, the samples exhibiting shear thinning are made from MPOSS nanosilica + 1 wt% 1173 (photoinitiator) system made of dipropylene glycol monomethyl ether 2 wt% (DiPGME, Dowanol DPM™)

Stable shear with recovery is only monitored based on viscosity and used to see how the structures recover. Use a 50 mm cone plate of 23 C for testing. The test sequence begins with a 60 second hold followed by a 60 second low shear (0.5 s-1) time sweep to establish a viscosity baseline. The samples were then subjected to high shear force (100 s-1) for 60 seconds and then to low shear force for 1000 seconds to monitor the recovery of the mixture: (1) MPOSS Nanosilica + 1173 1 wt% + Texanol 2 wt%, (2) MPOSS nanosilica + 1173 1 wt% + Texanol 4 wt%, (3) MPOSS nanosilica + 1173 1 wt% + Texanol 2 wt% + IPA 3 wt%, and ( 4) MPOSS Nanosilica + 1173 1 wt% + DiPGME 2 wt% or 5 wt% or 10 wt%. All four samples labeled 1 to 4 above seem to have measurable recovery times, with (2) MPOSS Nanosilica 1173 1% Tex 4% samples being the fastest, at about 90 seconds. Mixtures (1) and (3) took longer, about 10 minutes. The recovery of the mixture (4) took 900 seconds with 2 wt% DiPGME, more than 1000 seconds with 5 wt% DiPGME, and about 900 seconds with 10 wt% DiPGME . These samples are plotted separately in Figures 19 to 20 because their viscosity is much higher than the other three samples.

Figure 21 shows a pair of glass LGP (with a screen-printed microstructure manufactured according to one or more embodiments of the present invention compared to bare glass LGP (left) and glass LGP with laminated lentil-like film (right) ( In the middle, WS01486) the results of the optical limitation measurement. Figure 22 shows the optical limitations expressed by the normalized optical brightness curve of the glass LGP with screen-printed microstructures at a distance of 250 mm from the input edge as a function of position (mm), and its Laurent used to calculate LDI Now fit the curve. At a distance of 250 mm from the input edge, an LDI of about 81% for a dimming width of 150 mm is achieved. Figure 23A is a SEM photograph of the top view of the screen-printed elongated polymer microstructure using the MPOSS nano/Texanol/initiator system: the printed 150 μm width structure, 1 printed layer results in about 20 μm (contact angle is about 22 To 29 degrees).

Figure 23B is a SEM photograph of a side view of the screen-printed elongated polymer microstructure shown in Figure 23A.

Figure 23C is an SEM photograph of an enlarged side view of a single one of the screen-printed elongated polymer microstructures shown in Figure 23B.

Figure 24A is a SEM photograph of the top view of the screen-printed elongated polymer microstructure using the MPOSS nano/Texanol/initiator system: the printed two layers achieve about 30 μm (contact angle is about 40 to 42 degrees) and 3 The layer results in a 40 μm feature height.

Figure 24B is a SEM photograph of a side view of the screen-printed elongated polymer microstructure shown in Figure 24A.

Figure 24C is an SEM photograph of an enlarged side view of a single one of the screen-printed elongated polymer microstructures shown in Figure 24B.

Three layers result in a 40 μm feature height.

Figure 25A is a SEM photograph of a side view of a printed layer based on a side view of a microstructure of an elongated polymer microstructure printed using the MPOSS nano/Dowanol/initiator system. The microstructures of these printed elongated polymers are 120 μm wide. One printed layer results in a microstructure with a height of approximately 22 μm and a contact angle of approximately 26 degrees.

Figure 25B is a SEM photograph of a side view of the microstructure of an elongated polymer printed by screen printing using the MPOSS nano/Dowanol/initiator system based on two printed layers. The two printed layers achieve a microstructure height of approximately 30 μm and a contact angle in the range of 26 to 34 degrees.

According to one or more embodiments, the elongated polymer microstructure includes a contact angle in the range of about 20 degrees to about 50 degrees.

According to another aspect of the present invention, it has been found that a reduction in the surface tilt angle of the corrugations of the elongated polymer microstructures on the glass substrate reduces light leakage from light guide plates containing elongated polymer microstructures used as lentil-like features. In addition, the area dimming index and straightness (light limitation) decrease with the surface tilt angle. Based on the modeling results, it is determined that the surface tilt angle of the corrugations of the elongated polymer microstructures is less than 15 degrees, less than 10 degrees, less than 9 degrees, less than 8 degrees, less than 7 degrees, less than 6 degrees, less than 5 degrees, less than 4 degrees , Less than 3 degrees or less than 2 degrees.

The modeling is based on a light guide plate including a glass substrate having a refractive index of 1.5, a thickness of 1.1 mm, and a length of 500 mm by 500 mm by width, and the formation on the main surface 30 of the glass substrate 28 Lentil-like features of elongated microstructure 70. The microstructures of the elongated polymers are similar to those of the elongated polymers shown in FIG. 3D, in which the width W and height H of the lentil-like features are W=0.3 mm and H=0.15 mm, and the elongated polymers The cross-section of the object microstructure has a semi-circular shape. Modeling also included a gap S of 0.15 mm between the two elongated polymer microstructures. As shown in FIG. 26, the modeling is further based on the section 250 being located at a distance of 200 mm from the edge surface 29 coupled to the light source (not shown). According to this model, the segment 250 has a length of 4 mm, in which the surface of the elongated polymer microstructure fluctuates or is wavy along the lentil-like direction (Z direction in Fig. 26). According to one or more embodiments, the term "wavy", "wavy" or "corrugated" means that the uppermost surface 71 of the elongated polymer microstructure 70 includes disturbances such that it exists along the length L of the elongated polymer microstructure difference in height, and as shown in FIG. 27, there is a minimum height H greater than the maximum height of the elongated polymer microstructure ₂ H _1, figure 27 shows the elongation of the polymeric microelements 26 taken along line 27-27 of FIG. Cross-sectional view of structure 70. According to the model, the corrugation of the cross section 250 of the elongated polymer microstructure includes four wave periods 250a, 250b, 250c and 250d with a period of 1 mm. The enlarged view in Figure 27 shows one of the four wave periods 250a. According to the model, the ripple amplitude is determined by the surface inclination angle α defined by the angle between the lentil-shaped surface and the axis Z, which can be determined by the angle formed between: parallel to the glass substrate 28 major surface 30 of the z-axis, and the maximum height H is between one of the elongated polymer microstructure ₁ of the first uppermost surface 71a of one of the elongated second uppermost polymer microstructure at a minimum height H ₂ of the surface 71b The extended line is shown in Figure 27.

The performance of area dimming optics for 1D light limitations (or 1D area dimming) can be evaluated by two parameters: area dimming index (LDI) and straightness. As shown in Figure 28, Figure 28 is a schematic diagram used to describe the definition of the area dimming index (LDI) and straightness. The LDI and straightness at a distance Z from the LED input edge are defined as

Where L _m is the brightness of the area A _m in the zone m (m=n-2, n-1, n, n+1, n+2) at a distance Z from the LED input edge.

Figure 29 is a graph showing light leakage (percentage of total light coupled into the LGP) along the lentil-shaped direction as a function of the inclination angle of the surface of the lentil-shaped ripples. Obviously, as the angle of inclination of the lentil-like corrugated surface increases, light leakage increases.

Figures 30 and 31 show the model-based LDI (for 150 mm dimming width) and straightness at a distance of 450 mm from the input edge along the lentil-shaped direction with the surface inclination angle of the lentil-shaped corrugation. Figure. As the surface tilt angle increases, the LDI decreases and the straightness increases.

Based on the above modeling results, it is determined that the surface inclination angle of the corrugations of the elongated polymer microstructures 70 providing lentil-like features is less than 15 degrees, less than 10 degrees, less than 9 degrees, less than 8 degrees, less than 7 degrees, less than 6 degrees , Less than 5 degrees, less than 4 degrees, less than 3 degrees or less than 2 degrees of surface tilt angle, wherein the surface tilt angle is defined by an angle formed between the following two: parallel to the main surface 30 of the glass substrate 28 (In some embodiments, the main surface is a light-emitting surface) a line, and a first uppermost surface 71a of the elongated polymer microstructure at the maximum height H ₁ and the elongated polymer at the minimum height H ₂ A line extending between the second uppermost surface 71b of one of the microstructures.

According to one or more embodiments, light guide plates are provided that include a glass substrate and an elongated polymer microstructure on one major surface of the glass substrate. The elongated polymer microstructures 70 have a range of about 0.1 to about 10, such as about 2 to 9, about 2 to about 8, about 2 to about 7, about 2.5 to about 6, or about 2.5 to about 5 (including All ranges and subranges therebetween) one of W/H, and have less than 15 degrees, less than 10 degrees, less than 9 degrees, less than 8 degrees, less than 7 degrees, less than 6 degrees, less than 5 degrees, less than 4 degrees, less than 3 Degree or less than 2 degrees of surface tilt angle, wherein the surface tilt angle is defined by an angle formed between the following two: parallel to the main surface 30 of the glass substrate 28 (in some embodiments, the main surface is a light emitting surface) of the line, and the maximum height H is between one of the elongated polymer microstructure ₁ of the first uppermost surface 71a of one of the elongated second uppermost polymer microstructure at a minimum height H ₂ of the surface 71b An extended line. Furthermore, the elongated polymer microstructure 70 having a surface inclination angle less than these values according to an embodiment of the present invention exhibits the smallest ripples.

The light guide plates described herein can be used when manufacturing displays, lighting, or electronic devices.

Another aspect of the invention relates to a method of manufacturing a light guide plate. The method according to the first embodiment includes: depositing an array of elongated beads containing a first layer of curable liquid on a main surface of a glass substrate; at least partially curing the elongated beads containing the first layer of curable liquid using radiation Array to provide a plurality of at least partially cured elongated first layers separated by a distance S; depositing an array of elongated beads comprising a second layer of curable liquid on the plurality of at least partially cured elongated first layers; and The second layer of curable liquid is at least partially cured to form an array of elongated polymer multilayer microstructures including n layers, where n is in the range of 2 to 10.

In some embodiments of the method, at least partial radiation curing occurs less than 30 seconds, 10 seconds, or 1 second after the first layer and the second layer have been deposited.

In some embodiments of the method, the first layer and the second layer are deposited by a screen printing process. In some embodiments, the first layer and the second layer are continuously deposited using a nozzle under fluid pressure. In some embodiments, the radiation includes an ultraviolet lamp.

According to some embodiments, a light guide plate formed by the methods described herein includes a plurality of elongated polymer multilayer microstructures on the main surface of the glass substrate, one of the plurality of elongated polymer multilayer microstructures Each includes a surface tilt angle of less than 15 degrees, and wherein the surface tilt angle is defined by an angle formed between: a line parallel to the main surface of the glass substrate, and at a maximum height one of the elongated polymer H microstructure ₁ of the first uppermost surface 71a and at a minimum height H of the elongated microstructures one second polymeric multilayer line extending between the uppermost surface 71b _2.

According to some embodiments, a light guide plate formed by the methods described herein includes a plurality of elongated polymer multilayer microstructures on the main surface of the glass substrate, one of the plurality of elongated polymer multilayer microstructures Each, each of the plurality of elongated polymer multilayer microstructures has a maximum height H and a width W measured at one-half (H/2) of the maximum height, and is included in about 0.1 to about An aspect ratio W/H within a range of 10.

In some embodiments, the light guide plate formed by the methods described herein includes a plurality of elongated polymer multilayer microstructures on the main surface of the glass substrate, the plurality of elongated polymer multilayer microstructures Each of the plurality of elongated polymer multilayer microstructures has a maximum height H and a width W measured at one-half (H/2) of the maximum height, and is included in about 0.1 to about 10 The aspect ratio W/H within the range.

Another aspect of the present invention relates to a method of forming a light guide plate, the method comprising the steps of: depositing a curable liquid on a main surface of a glass substrate to form an array of first curable liquid layers separated by elongated spaces ; At least partially curing the array of elongated spaced apart curable liquid layers to provide an array of spaced apart at least partially cured polymer layers; deposited on the array of spaced apart at least partially cured polymer layers Curing the liquid to form an array of elongated spaced apart second curable liquid layers; and at least partially curing the curable liquid on the array of spaced apart at least partially cured polymer layers to form an elongated polymer An array of multilayer microstructures, the array of elongated polymer multilayer microstructures includes n layers, where n is in the range of 2 to 10. In some embodiments of the current method, each of the elongated polymer multilayer microstructures of the array has a maximum height H and a width W measured at one-half (H/2) of the maximum height, such that the extensions The polymer microstructure has an aspect ratio W/H for 1D dimming of LED light. In some embodiments of the current method, the light guide plate formed by the method includes a plurality of elongated polymer multilayer microstructures on the main surface of the glass substrate, each of the plurality of elongated polymer multilayer microstructures Includes a surface tilt angle of less than 15 degrees, and wherein the surface tilt angle is defined by the angle formed between: a line parallel to the main surface of the glass substrate, and at a maximum height H ₁ the first surface 71a and the uppermost line extending between the surface 71b is at a minimum height H of the elongated second uppermost multilamellar structures of the polymer microstructure ₂ of the elongated polymer.

In some embodiments of the method, the light guide plate formed by the method includes a plurality of elongated polymer multilayer microstructures on the main surface of the glass substrate, each of the plurality of elongated polymer multilayer microstructures , Each of the plurality of elongated polymer multilayer microstructures has a maximum height H and a width W measured at one-half (H/2) of the maximum height, and is included in the range of about 0.1 to about 10 The aspect ratio W/H.

Ranges are expressed herein as "about" one specific value and/or to "about" another specific value. When expressing this range, another embodiment includes from the one specific value and/or to the other specific value. Similarly, when a value is expressed as an approximate value by using the aforementioned word "about", it will be understood that the specific value forms another embodiment. It will be further understood that the endpoint of each of these ranges is not only significant for the other endpoint, but is independent of the other endpoint.

Directional terms such as up, down, right, left, front, back, top, bottom as used herein refer only to the drawings drawn and are not intended to imply absolute orientation.

Unless expressly stated otherwise, it is by no means intended that any method set forth herein should be interpreted as requiring the steps of the method to be performed in a specific order, nor does it require any equipment to have a specific orientation. Accordingly, the order in which the method steps should not be actually listed in the method request item, or the order or orientation of any device request item that does not actually list the individual components, or the patent application or the specification does not specifically state that these steps should be limited to In the event that a specific order, or a specific order or orientation of the components of the device is not listed, in no way is it intended to infer the order or orientation. As used herein, the singular forms "a" and "the" include plural references unless the context clearly indicates otherwise. Thus, for example, reference to "a" component includes the appearance of having two or more such components, unless the context clearly indicates otherwise.

Those skilled in the art will understand that various modifications and changes can be made to the embodiments of the present invention without departing from the spirit and scope of the invention. Therefore, it is hoped that the present invention covers such modifications and changes, and the limitation is that such modifications and changes are within the scope of the appended patent applications and their equivalents.

10‧‧‧LCD display device 12‧‧‧LCD display panel 14‧‧‧ first substrate 16‧‧‧second substrate 18‧‧‧ adhesive material 20‧‧‧gap 22‧‧‧polarizing filter 24‧‧ ‧Backlight unit (BLU) 26‧‧‧Glass light guide plate (LGP) 27-27‧‧‧Line 28‧‧‧Glass substrate 29‧‧‧Edge surface 30‧‧‧Main surface 32‧‧‧Main Surface 34a‧‧‧Edge surface 34b‧‧‧Edge surface 34c‧‧‧Edge surface 34d‧‧‧Edge surface 36‧‧‧Light emitting diode (LED) 38‧‧‧Reflector plate 40‧‧‧Light source 40a‧ ‧‧The first sub-array 40b of LED‧‧‧‧The second sub-array 40c of LED‧‧‧‧The third sub-array of LED 60‧‧‧Channel 70‧‧‧ Polymer microstructure/Polymer multilayer microstructure 70a‧‧ ‧The first polymer layer 70b‧‧‧The second polymer layer 70c‧‧‧The third polymer layer 71‧‧‧The uppermost surface 71a‧‧‧The first uppermost surface 71b‧‧‧The second uppermost surface 72‧‧ ‧Polymer platform 160‧‧‧Luminous surface 161‧‧‧Arrow 162‧‧‧Dummy arrow 170‧‧‧Second main surface 200‧‧‧Equipment 215‧‧‧Reservoir 216‧‧‧Pump or fluid distribution device 217‧‧‧ pressure sensor 218‧‧‧ air supply line/air pressure line 219‧‧‧ air supply source 220‧‧‧ regulator valve 221‧‧‧controller 223‧‧‧ fluid supply line 234‧‧ ‧Arrow 226‧‧‧Pressure reading/pressure sensor signal 227‧‧‧Control signal 228‧‧‧Distributor tip or nozzle 230‧‧‧Radiation source 234‧‧‧Arrow 250‧‧‧Section 250a‧‧‧ Wave period 250b‧wave period 250c‧‧‧wave period 250d‧‧‧wave period A‧‧‧region B‧‧‧region C‧‧‧region d ₁ ‧‧‧thickness S‧‧‧ first interval/distance S2‧‧‧Second interval T‧‧‧Light guide plate thickness t‧‧‧Maximum glass substrate thickness t2‧‧‧Polymer platform thickness H‧‧‧Maximum height H ₁ ‧‧‧Maximum height H ₂ ‧‧‧Minimum height L‧‧‧LGP length L2‧‧‧second length W‧‧‧width θ‧‧‧contact angle

Figure 1 is a cross-sectional view of an exemplary LCD display device;

Figure 2 is a plan view of an exemplary light guide plate;

Figure 3A is a cross-sectional view of a glass substrate including a plurality of polymer multilayer microstructures on its surface and suitable for use with the glass light guide plate of Figure 2;

Figure 3B is a cross-sectional view of another glass substrate, which contains a plurality of polymer multilayer microstructures on its surface and is suitable for use with the glass light guide plate of Figure 2;

Figure 3C is a cross-sectional view of yet another glass substrate, which includes a plurality of polymer multilayer microstructures on its surface and is suitable for use with the glass light guide plate of Figure 2;

Figure 3D is a cross-sectional view of yet another glass substrate including a plurality of polymer multilayer microstructures on its surface and suitable for use with the glass light guide plate of Figure 2;

Figure 3E is a cross-sectional view of yet another glass substrate, which includes a plurality of polymer multilayer microstructures on a polymer platform on its surface and is suitable for use with the glass light guide plate of Figure 2;

Figure 3F is an SEM image of the microstructured surface of a non-periodic array of polymer multilayers;

Figure 4 illustrates a light guide plate according to a specific embodiment of the invention;

Figure 5 illustrates a polymer multilayer microstructure according to a specific embodiment of the invention;

Figure 6A illustrates a polymer multilayer microstructure according to a specific embodiment of the invention;

FIG. 6B is a diagram of the contact angle varying with the aspect ratio W/H according to an embodiment;

Figure 7A is a schematic diagram of stable, undisturbed continuous elongated beads that can form a polymer microstructure material according to an embodiment of the present invention;

Figure 7B is a schematic diagram of a liquid bead with a contact angle θ, which remains fixed at a balanced value when the contact line moves freely;

Figure 7C is a schematic diagram of liquid beads with a contact angle that depends on the contact linear velocity but decreases to an equilibrium value at zero speed and beads with a contact line that stops in a parallel state when the contact angle changes freely;

Figure 8A is a scanning electron microscope (SEM) photograph of a top view of an elongated polymer microstructure on a glass substrate;

Figure 8B is a scanning electron microscope (SEM) photograph of a cross-sectional view of an elongated polymer microstructure on a glass substrate;

Figure 8C is a scanning electron microscope (SEM) photograph of an enlarged cross-sectional view of an elongated polymer microstructure on a glass substrate;

Figure 9A shows an optical image of lentil-like features generated on a 20.3 cm x 27.9 cm IRIS glass substrate;

Figure 9B shows an optical image of lentil-like features generated on a 20.3 cm x 27.9 cm IRIS glass substrate;

Figure 10A shows an optical image of lentil-like features generated on a 20.3 cm x 27.9 cm IRIS glass substrate;

Figure 10B shows an optical image of lentil-like features generated on a 20.3 cm x 27.9 cm IRIS glass substrate;

Figure 11A shows the results of optical limitation measurements on the 280 mm x 215 mm bare glass sample and the laminated lentil lens structure on the 280 mm x 215 mm glass sample;

Figure 11B shows the results of light limitation measurements of continuously dispersed microstructures on a 280 mm x 215 mm glass sample;

Figure 11C shows the results of the measurement of light limitations on continuously dispersed microstructures on a 280 mm x 215 mm glass sample;

Figure 12A shows the normalized optical brightness curves of bare glass LGP with a distance of 250 mm from the input edge, glass LGP with laminated lentil film, and glass LGP with dispersed microstructures Optical limitations;

Figure 12B shows the light limitations expressed by the normalized optical brightness curve of the glass LGP with dispersed microstructures that are 250 mm away from the input edge as a function of position (mm), and the resulting Lorentz fit curve;

Figure 13 shows the light limitations expressed by the normalized optical brightness curves of the glass LGP with laminated lentil-like film and the glass LGP with dispersed microstructures that vary with the position (mm) by 250 mm from the input edge;

FIG. 14 is a block diagram of an embodiment of an apparatus 200 that can be used to continuously dispense and solidify a curable liquid according to an embodiment of the present invention;

Figure 15 is a graph showing the color shift (difference chromaticity y value at 320 mm) of coated samples with a thickness greater than 10 μm manufactured using various materials;

Figure 16 is a depiction of the steps that can be used to screen print the elongated polymer microstructure according to an embodiment of the present invention;

Figure 17 is a graph showing the stable shear sweep (shear viscosity versus shear rate) of screen printing ink containing Texanol solvent;

Figure 18 is a graph showing the stable shear sweep (shear viscosity versus shear rate) of screen printing inks containing diethylene glycol monomethyl (Dowanol DPM™ solvent);

Figure 19 is a graph showing the shear viscosity of two screen printing inks containing Texanol™ solvent versus time;

Figure 20 is a graph showing the shear viscosity of three screen printing inks containing Dowanol DPM™ solvent versus time;

Figure 21 shows the optical limitation measurements performed on glass LGP with screen-printed microstructures manufactured according to one or more embodiments of the present invention compared to bare glass LGP and glass LGP with laminated lentil-like films Result

Figure 22 is a graph showing the light limitations of the normalized optical brightness and the Lorentz fitting curve of the glass LGP with screen-printed microstructures 250 mm away from the input edge as a function of position (mm);

Figure 23A is a SEM photograph of the top view of the screen-printed elongated polymer microstructure;

Figure 23B is a SEM photograph of a side view of the screen-printed elongated polymer microstructure shown in Figure 23A;

Figure 23C is an SEM photograph of an enlarged side view of a single one of the screen-printed elongated polymer microstructures shown in Figure 23B;

Figure 24A is a SEM photograph of the top view of the screen-printed elongated polymer microstructure;

Figure 24B is a SEM photograph of a side view of the screen-printed elongated polymer microstructure shown in Figure 24A;

Figure 24C is an SEM photograph of an enlarged side view of a single one of the screen-printed elongated polymer microstructures shown in Figure 24B;

Figure 25A is a SEM photograph of a side view of the screen-printed elongated polymer microstructure;

Figure 25B is a SEM photograph of a side view of the screen-printed elongated polymer microstructure;

Figure 26 is a top plan view of a light guide plate with an elongated polymer microstructure on a glass substrate;

Figure 27 shows a cross-sectional view of the elongated polymer microstructure 70 taken along the line 27-27 of Figure 26;

Figure 28 is a schematic diagram for describing the definitions of local dimming index (LDI) and straightness;

Figure 29 is a graph showing light leakage (percentage of total light coupled into the LGP) along the lentil-shaped direction with the tilt angle of the surface of the lentil-shaped corrugation based on the model;

Figure 30 is a graph showing LDI (for 150 mm dimming width) at a distance of 450 mm from the input edge based on the modeled change in the lentil-shaped direction with the surface inclination angle of the lentil-shaped corrugations;

Figure 31 is a graph showing the straightness of the lentil-shaped corrugation along the lentil-shaped corrugated surface with a tilt angle of 450 mm away from the input edge based on the model.

Domestic storage information (please note in order of storage institution, date, number) no

Overseas hosting information (please note in order of hosting country, institution, date, number) no

200‧‧‧Equipment

215‧‧‧reservoir

216‧‧‧Pump or fluid distribution device

217‧‧‧ pressure sensor

218‧‧‧Air supply line/air pressure line

219‧‧‧ gas supply

220‧‧‧ Regulator valve

221‧‧‧Controller

223‧‧‧Fluid supply line

226‧‧‧pressure reading/pressure sensor signal

227‧‧‧Control signal

228‧‧‧Distributor tip or nozzle

230‧‧‧radiation source

234‧‧‧arrow

Claims (41)

A light guide plate includes: A glass substrate including an edge surface and two major surfaces; and a plurality of elongated polymer multilayer microstructures on at least one of the major surfaces, each elongated multilayer microstructure having a maximum height H And a width W measured at one-half (H/2) of the maximum height, and further includes an aspect ratio W/H in a range of about 0.1 to about 10. The light guide plate according to claim 1, wherein the aspect ratio is in a range of about 2 to about 8. The light guide plate according to claim 1, wherein the aspect ratio is in a range of about 2.5 to about 6. The light guide plate according to claim 1, wherein the height H of each elongated polymer multilayer microstructure does not exceed 50 μm. The light guide plate of claim 1, wherein W is between about 50 μm and about 500 μm. The light guide plate of claim 1, wherein each elongated polymer multilayer microstructure comprises n layers, where n is in the range of 3 to 10. The light guide plate according to claim 1, wherein a first interval S in a first direction between two adjacent elongated polymer multilayer microstructures of the plurality of microstructures is between about 0.01*W and 4*W Within one. The light guide plate of claim 1, wherein at least one of the plurality of elongated polymer multilayer microstructures further includes a length L, and wherein the other of the plurality of elongated polymer multilayer microstructures has a different One of L is length L2. The light guide plate according to claim 1, wherein the glass substrate includes: 50 to 90 mol% SiO ₂ , 0 to 20 mol% Al ₂ O ₃ , 0 to 20 mol% B based on mol% oxide ₂ O ₃ , and 0 to 25 mol% R _x O, where x is 2, and R is selected from Li, Na, K, Rb, Cs, and combinations thereof, or where x is 1, and R is selected from Zn , Mg, Ca, Sr, Ba and their combinations. The light guide plate according to claim 1, wherein a thickness t of the glass substrate is in the range of about 0.1 mm to about 3 mm. The light guide plate of claim 1, wherein the plurality of elongated polymer multilayer microstructures comprise a UV-curable or heat-curable polymer. The light guide plate according to claim 1, wherein the glass substrate further includes a plurality of light extraction features patterned on one main surface of the glass substrate opposite to the light emitting surface. The light guide plate of claim 1, wherein each elongated polymer multilayer microstructure includes a surface tilt angle of less than 15 degrees, and wherein the surface tilt angle is defined by an angle formed between: parallel A line on the light emitting surface of the glass substrate, and a first uppermost surface of one of the elongated polymer microstructures at a maximum height H _{1 and} a second uppermost surface of the elongated polymer microstructures at a minimum height H ₂ A line extending between. The light guide plate according to claim 13, wherein the inclination angle of the surface is less than 10 degrees. The light guide plate according to claim 13, wherein the inclination angle of the surface is less than 4 degrees. The light guide plate according to claim 13, wherein the inclination angle of the surface is less than 2 degrees. A light guide plate includes: a glass substrate including an edge surface and at least two main surfaces; and a plurality of elongated polymer microstructures on at least one of the main surfaces, each The elongated polymer microstructure includes a surface tilt angle of less than 15 degrees, and wherein the surface tilt angle is defined by an angle formed between: a line parallel to the light-emitting surface of the glass substrate, and at the maximum one of the height H of the elongated polymer micro _structure of the first surface is uppermost line extending between one of the minimum height H ₂ of the microstructure of the polymer elongate second outermost surface. The light guide plate according to claim 17, wherein the surface tilt angle is less than 10 degrees. The light guide plate according to claim 17, wherein the inclination angle of the surface is less than 4 degrees. The light guide plate according to claim 17, wherein the surface tilt angle is less than 2 degrees. The light guide plate of claim 17, wherein each elongated polymer microstructure includes n layers, and wherein n is in the range of 2 to 10. The light guide plate according to claim 21, wherein n is in a range of 2 to 5. A method for manufacturing a light guide plate, the method includes the following steps: Depositing a first layer of curable liquid on a major surface of a glass substrate as a first array of elongated liquid beads; at least partially radiation curing the first layer of curable liquid to provide at least a separation distance S An array of partially cured elongated microstructures; depositing a second layer of curable liquid on the first array of at least partially cured elongated beads as a second array of elongated liquid beads; at least partially radiation curing the A second layer of curable liquid to provide a bilayer array of at least partially cured elongated microstructures; and optionally forming an additional layer of curable liquid on the at least partially cured elongated microstructures of the bilayer array to provide A multilayer array of n layers of elongated polymer multilayer microstructures, where n is in the range of 2 to 10. The method of claim 23, wherein at least partial radiation curing occurs less than 30 seconds after the first layer of curable liquid has been deposited and less than 30 seconds after the second layer of curable liquid has been deposited. The method of claim 23, wherein at least partial radiation curing occurs less than 10 seconds after the first layer of curable liquid has been deposited and less than 10 seconds after the second layer of curable liquid has been deposited. The method of claim 23, wherein at least partial radiation curing occurs less than 5 seconds after the first layer of curable liquid has been deposited and less than 5 seconds after the second layer of curable liquid has been deposited. The method of claim 23, wherein at least partial radiation curing occurs less than 1 second after the first layer of curable liquid has been deposited and less than 1 second after the second layer of curable liquid has been deposited. The method of claim 23, wherein the first layer and the second layer are deposited by a screen printing process. The method of claim 28, wherein the radiation comprises ultraviolet light. The method of claim 28, wherein each elongated polymer multilayer microstructure includes a surface tilt angle of less than 15 degrees, and wherein the surface tilt angle is defined by an angle formed between: parallel to A line of the main surface of the glass substrate, and a first uppermost surface of one of the elongated polymer microstructures at the maximum height H _{1 and} a second uppermost surface of the elongated polymer multilayer microstructures at the minimum height H ₂ A line extending between. The method of claim 28, each of the elongated polymer multilayer microstructures has a maximum height H and a width W measured at one-half (H/2) of the maximum height, and is included in about 0.1 to about 10 One aspect ratio W/H within one range. The method of claim 23, wherein the first layer and the second layer are continuously deposited using a nozzle under fluid pressure. The method of claim 32, wherein the radiation comprises ultraviolet light. The method of claim 33, wherein each elongated polymer multilayer microstructure includes a surface tilt angle of less than 15 degrees, and wherein the surface tilt angle is defined by an angle formed between: parallel to A line of the main surface of the glass substrate, and a first uppermost surface of one of the elongated polymer microstructures at the maximum height H _{1 and} a second uppermost surface of the elongated polymer multilayer microstructures at the minimum height H ₂ A line extending between. The method of claim 33, wherein each elongated polymer multilayer microstructure has a maximum height H and a width W measured at one-half (H/2) of the maximum height, and further includes about 0.1 to An aspect ratio W/H within a range of about 10. The method of claim 23, wherein an inkjet printer is used to deposit the first layer and the second layer. A method for forming a light guide plate, the method includes the following steps: Depositing a curable liquid on a major surface of a glass substrate to provide an array of first spaced apart curable liquid layers; at least partially curing the array of spaced apart spaced curable liquid layers, to Forming an array of spaced apart at least partially cured polymer layers; depositing additional curable liquid on the array of spaced apart at least partially cured polymer layers to form an elongated spaced apart second curable liquid layer An array; an array of at least partially cured elongated spaced apart second curable liquid layers to form an array of at least partially cured elongated polymer multilayer microstructures; and at least partially cured elongated polymer multilayer microstructures An additional array of at least partially cured elongated polymer microstructures is optionally formed on the array such that the array of at least partially cured elongated polymer multilayer microstructures includes n layers, where n is in the range of 2 to 10 . The method of claim 37, wherein each elongated polymer multilayer microstructure has a maximum height H, a width W measured at one-half (H/2) of the maximum height, and a 1D adjustment for LED light One aspect ratio of light is W/H. The method of claim 37, wherein each elongated polymer multilayer microstructure includes a surface tilt angle of less than 15 degrees, and wherein the surface tilt angle is defined by an angle formed between: parallel to A line of the main surface of the glass substrate, and a first uppermost surface of one of the elongated polymer microstructures at the maximum height H _{1 and} a second uppermost surface of the elongated polymer multilayer microstructures at the minimum height H ₂ A line extending between. The method of claim 37, wherein each elongated polymer multilayer microstructure has a maximum height H and a width W measured at one-half (H/2) of the maximum height, and at about 0.1 to about 10 One aspect ratio W/H within one range. The method of claim 37, wherein an inkjet printer is used to deposit the curable liquid and deposit the additional curable liquid.

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