KR100837027B1 - Microlens arrays - Google Patents

Abstract

The present invention relates to systems and methods for providing a structure for regulating light, commonly referred to as microlens or microlens array. For example, according to an embodiment of the present invention, the light adjusting structure may be adapted to provide a display screen such as a camera, personal digital assistant, telephone, computer screen or television.

Description

Micro Lens Array {MICROLENS ARRAYS}

The present invention is incorporated herein by reference in its entirety, as filed on January 8, 2004, entitled "Method for Making Micro-Lens Array," US Patent Application No. It is filed in part on 10 / 754,365.

FIELD OF THE INVENTION The present invention relates generally to optics and optical devices, and more particularly to microlens arrays, methods for fabricating such microlens arrays, and microlens array systems and applications.

Microlens arrays provide optical versatility in a miniature package for imaging applications. Traditionally, microlens has been defined as a lens with a diameter of 1 millimeter or less, but lenses with a diameter of 5 millimeters or more are sometimes considered as microlenses.

There are many conventional methods for manufacturing microlenses. For example, one technique commonly used to fabricate microlenses is to coat a substrate with a selected photoresist and to irradiate the photoresist coated substrate through a mask. Exposing to radiation, or alternatively, allowing the photoresist to undergo gray scale laser exposure. When heating the substrate, the exposed photoresist melts, and the surface tension pulls the material into the shape of the convex lens. The depth of the photoresist determines the focal length of the lens.

Another way to fabricate microlenses is to use ion exchange. In this method, ions are diffused into glass rods to give a radial refractive index distribution. The refractive index is highest at the center of the lens and decreases rapidly as a function of radial distance from the central axis. Microlenses made using ion exchange methods are used to collimate light from fibers, for example in telecommunication applications.

In general, in many applications, microlens arrays are preferred over discrete microlenses. As an example, one fabrication method for the production of glass microlens arrays generally involves reactive ion etching (RIE) of fused silica. In general, it is very difficult to meet all the requirements of microlens arrays using RIE. RIE technology involves many steps before the final product can be produced, so yields are generally low and products are expensive.

As another example, compression molding of optical quality glass to form microlens arrays is well known. This method involves compressing an optical element preform, commonly known as a gob, at high temperatures to form a glass lens element. In a compression molding process, a gob is inserted into a mold cavity. The mold stays in an oxygen-free chamber during the molding process. The gob is generally located on the lower mold and heated above the glass transition temperature and near the glass softening point. The upper mold is then brought into contact with the gob, and pressure is provided to conform the gob to the shape of the mold cavity. After cooling, the lens is removed from the mold.

Unfortunately, compression molding of an array of microlenses using one or more preforms results in alignment of the mechanical and optical axes of the respective lens elements with respect to a common axis and at a reference point within the array. There are many difficulties, which can include the location of each lens element relative to. Furthermore, if the microlens diameter is 1 mm or less, it is very difficult to machine the convex aspherical molding cavity using conventional techniques.

As another example, a microlens array can be a silicon chip for either light-sensitive applications (e.g. CCDs) or light-emitting applications (e.g. micro-display devices). It is often formed on the upper surface of the silicon chip. A planarization layer is first formed over the silicon substrate. The color filer layer is then formed over the planarization layer with sub-pixel areas properly aligned with the active device in the silicon substrate. Another planarization layer is generally formed over the color filter layer, and finally a photoresist material is disposed over the second planarization layer. Next, conventional lithographic techniques are used to form rectangular patterns in the photoresist. After exposure, a development step removes the photoresist in the exposed areas, leaving the central island area transparent over the pixel-active area. Development and sometimes etching remove the photoresist material between the central sites, form trenches in the photoresist sites, separate the islands of the photoresist and form individual microlens locations. do. Deep plasma etching into the silicon substrate then removes all layers on the substrate. Next, the photoresist is stripped off and the device is hard-baked to reflow the microlens back into the appropriate optical form by adjusting the time and temperature.

Although there are numerous conventional methods for fabricating microlenses and microlens arrays, these conventional techniques are difficult or expensive to fabricate, or are for example viewing angles, brightness, uniformity. , It does not meet certain design conditions such as contrast. Thus, there is a need for an improved microlens array.

Disclosed herein are systems and methods for providing a microlens array. For example, in accordance with an embodiment of the present invention, a method for fabricating a microlens array is disclosed. Microlens may be fabricated without the difficult or expensive fabrication steps required by some conventional microlens arrays. Microlens arrays may also meet design requirements for display screens such as, for example, brightness and uniformity, contrast or / and viewing angle. For example, a microlens array can be a television screen, a computer screen (ie, a computer monitor), a photocopy screen, a projection screen, a display screen (ie, a mobile phone display). Screen to wall-sized display screen), or may be used as a laptop screen or with other types such as imaging, optical systems or display systems.

According to an embodiment of the present invention, a method is provided for producing a microlens array, for example. The method includes binding or adhering together bundles of optically transparent members, such as rods or fibers. The bundle of optically transparent members is cut to form sheets of segments of the member. The cut or faces of the sheet may resemble a honeycomb structure. This face may be polished to smooth out all the rough edges that are produced by the cutting process. If desired, the ends or one or both faces of the sheet may be modified to mold the ends into the desired shape.

The modified ends are exposed to an energy source, such as a heat source, electrical spike, laser light, etc., with the ends of each member segment forming lens segments. The light-shielding layer may be located over the modified ends on both sides or one side of the sheet, for example allowing the lens segment of each member segment to be only partially exposed (ie Only the central regions of each lens segment allow light to pass through). One or more coatings may be provided on both sides of the sheet or only on one side (eg, anti-reflection coating or / and anti-glare coating). . The resulting microlens array may provide display screens for various applications (eg, projection screens, wall size display screens, from small display screens such as cameras, personal digital assistants, or laptops), Or large display screens for billboard-sized display screens).

Thus, the microlens array fabricated by the method of the present invention can be made large or small. For example, the size of the microlens array can be made from a size smaller than about 10 square micrometers to a wall display unit larger than 70 inches by 70 inches. Unlike other microlens array fabrication methods, each lens element is made with a high degree of lens size uniformity. As will be described in more detail below, lens element devices in an array may be fixed as desired or may meet the requirements of other applications.

More specifically, according to an embodiment of the present invention, a method for fabricating a microlens array provides a bundle of optically transparent members and forms at least one or more sheets of optically transparent member segments. At least one lens having an optically transparent member bundle to cut, heating at least one or more sheets of optically transparent member segments to form lens segments, and having a light-shielding layer Covering a portion of the segments.

According to another embodiment of the invention, the display screen comprises optically transparent members which are formed as one or more micro lens array strips and which are adapted to provide a path for light, each optically transparent The members are a lens formed on at least one end of the optically transparent members and a light-shielding layer applied adjacent to the sheet and applied to block some of the light while leaving each optically transparent member. Characterized in having a.

According to another embodiment of the present invention, a method for providing a display screen formed as a microlens array provides an optically transparent cylindrical rod that is bundled together to form a structure having a honeycomb-like cross section. providing, cutting an optically transparent cylindrical rod to form at least one sheet of optically transparent rod segments, wherein each optically transparent rod segment has a first end and a second end Applied to channel light, heating both ends to form a lens surface on the ends, covering a portion of the lens surface on the first ends with a light-shielding layer (covering).

The scope of the invention is defined by the claims, which are hereby incorporated by reference. By reference to the following detailed description of one or more embodiments, a more complete understanding of embodiments of the present invention and additional advantages is made by those skilled in the art. It will first be described briefly with reference to the accompanying drawings.

1 is a flowchart illustrating a method according to an embodiment of the present invention.

2 is a simplified view of a bundle of optically transparent members in accordance with an embodiment of the present invention.

3A is a simplified illustration of a cut sheet of an optically transparent member segment taken across the bundle of FIG. 2 in accordance with an embodiment of the present invention.

3B is a side view of a single optically transparent member segment in accordance with an embodiment of the present invention.

4A is a simplified plan view of an array of optically transparent member segments subjected to a heating treatment in accordance with an embodiment of the present invention.

4B is a simplified side view of an array of optically transparent member segments subjected to a heating treatment in accordance with an embodiment of the present invention.

5 is a simplified view of a light beam shape converter and a light interpreter used in a projection system including a microlens array according to an embodiment of the present invention.

6A, 6B, 6C, and 6D are side views schematically illustrating various configurations of a microlens array according to an embodiment of the present invention.

7A and 7B are simplified side views illustrating bundles of optically transparent members in accordance with an embodiment of the present invention.

8A and 8B are simplified views of standard cut optically transparent member segments undergoing an etch process according to an embodiment of the invention.

9 is a simplified view of optically transparent member segments undergoing heat treatment according to an embodiment of the present invention.

10 is a simplified view of a sheet of optically transparent member segments in accordance with an embodiment of the present invention.

FIG. 11 is a simplified side view of an array of optically transparent member segments having a light-shielding layer provided in accordance with an embodiment of the present invention. FIG.

12 is a simplified illustration of a sheet of optically transparent member segments employed in a display screen according to an embodiment of the invention.

Embodiments and advantages of the invention are better understood by the following detailed description. The same reference numerals are used for the same components shown in one or more of the figures.

1 is a flowchart illustrating a method 100 according to an embodiment of the present invention. The method 100 includes the provision of a bundle of optically transparent members, such as optically transparent rods or fibers made of, for example, glass, plastic, etc. (s102). . The bundle of optically transparent members is cut or sliced into sheets or sheets of the optically transparent member segment s104, each sheet having a first face and a second one. It has a face. Depending on the requirements of the application or as desired, the thickness of each sheet can be made to any thickness desired.

The ends of each optically transparent member segment in each sheet may be polished to create a smooth end (s106). The method 100 also includes modifying one or both sides of the sheet s106 to form the face of the sheet from a flat surface to a more rounded surface. Optionally, the end of each transparent member segment can be modified to create a lens structure of varying size and shape during the lens element formation process (s106).

As will be described in more detail below, one or both faces of each of the sheets of optically transparent member segments are subject to an energy source capable of providing a heating treatment. In operation S108, the lens element is formed on the end or the ends of the optically transparent member segments. In addition, the newly formed array of lens elements may be coated using, for example, a thin film if necessary (S110). The coating may include an anti-reflection or anti-glare material for display screen applications.

2 is a simplified illustration of a bundle 200 of multiple optically transparent members 202 in accordance with an embodiment of the present invention. According to one embodiment of the invention, each optically transparent member 202 is a rod, cylinder, fiber or other similarly formed that can provide a path for light. Members can be. The plurality of optically transparent members 202 are tied together along the longitudinal axis of each of the members (s102). The resulting structure has a cross section similar to the honeycomb structure.

In one embodiment of the invention, the optically transparent members 202 may be tied together to form the bundle 200 using any suitable adhesive, such as an ultraviolet curable adhesive or the like. . Advantageously, when using an ultraviolet curable adhesive to form a bundle 200 of optically transparent members 202, any gaps that may be present between the members may be filled with the adhesive before the adhesive is cured. have. Alternatively, the bundle 200 may be formed during the drawing / polling process.

Optically transparent members 202 may be made of various materials. For example, in one embodiment, the optically transparent members 202 are made of glass (SiO2), plastic, polymer wire or other similar optically transparent material. The diameter and length of each optically transparent member 202 that makes up the bundle 200 is generally indicated by the application.

In one embodiment of the invention, for example, when fabricating a microlens array, the thickness of the bundle 200 (eg, the length of the member 202) is desired by the application of the microlens array. It is made greater than or at least equal to the thickness. As shown in FIG. 3A, to ensure proper thickness, the bundle 200 forms a single layer or sheet 300 to form an array of optically transparent member segments 302 having a thickness t. It can be cut into (S104). Thus, the length of the optically transparent member 202 must be equal to or greater than t. The bundle 200 can be cut into sheets or multiple sheets 300 using conventional cutting techniques, for example by employing a dicing saw or / and a cutting wheel. have.

For example, in one embodiment of providing a microlens array for an imaging system such as a camera, the thickness of each sheet 300 of the optically transparent member segment 302 may be about 100 μm. The thickness may be more than a few millimeters for an image projection system using a light integrator.

In one embodiment of the invention, each optically transparent member 202 in the bundle 200 may be a standard single mode fiber, which has a core size of 9 μm and about 125 μm Has the full diameter. In general, the diameter of each optically transparent member 202 may range from less than one millimeter to about several millimeters, depending on the application. In general, the pre-bundled optically transparent members 202 of FIG. 2 designed to the desired specifications to suit a particular application are available for use from Corning, Inc., for example, in New York.

7A and 7B show simplified side views of a bundle 700 (ie, bundle 700a and bundle 700b for FIGS. 7A and 7B, respectively) according to embodiments of the present invention. In one embodiment, the bundle 700a may be made to include optically transparent members having individually varying diameters. For example, in FIG. 7A bundle 700a is shown as having an optically transparent member 702a having a diameter d1 and an optically transparent member 702b having a diameter d2, where d2 is greater than d1. In this embodiment, the optically transparent members 702a are disposed on the circumferential region A1 of the bundle 700a and the optically transparent members 702b are in the core region A2 of the bundle 700a. To be deployed.

In this example, the light intensity of the light input 704 directed to the microlens array formed from the bundle 700a in accordance with the principles of the present invention is shown in the intensity curve 706. As can be expected to be redistributed. Redistribution of light intensity is useful in systems such as image projection systems such as cameras.

7B shows a bundle 700b having optically transparent members 702c having a diameter d4 and optically transparent members 702d having a diameter d3, where d3 is larger than d4. In this embodiment, the optically transparent members 702d are disposed on the circumferential region A3 of the bundle 700b, and the optically transparent member 702c is in the core region A4 of the bundle 700b. To be deployed.

In this example, the beam intensity of the light input 708 directed to the microlens array formed from the bundle 700b in accordance with the principles of the present invention is shown in the intensity curve 710. As can be expected to be redistributed,

As shown in FIGS. 3A and 3B, the ends 304, 306 can be modified if the sheet 300 of optically transparent member segments 302 is cut to the desired thickness t. In one embodiment, the ends or faces 304, 306 of the cut sheet 300 may be polished to form a smooth flat surface on one or both ends of the sheet 300. It may or may not be "clear".

In another embodiment, polishing is the curvature of each side 304, 306 of the sheet 300 to form and optimize the desired microlens array surface on one or both sides of the sheet 300. Can be used to modify the curvature, size and related parameters. The shape of the array surfaces may be determined by the required application.

For example, briefly with respect to FIG. 6D, the simplified diagram shows an embodiment of a microlens array 608 with lenses formed in a bent manner on one surface (ie, surface 610). . In one embodiment, the curvature of the surface 610 of the array 608 may be controlled during the polishing process. For example, a polishing arm may be allowed to swing while the array 608 rotates, thus forming a curved surface of the member segment 302 on the face 304.

The individual shapes of the ends 304, 306 of each optically transparent member segment 302 (FIG. 3B) are adjusted or modified to produce the curvature, size and parameters of each optically transparent member segment 302. Can be made (s106). The modification can be performed using various techniques such as polishing, etching, acid etching, and the like.

In one embodiment, the respective ends 304, 306 may be modified in various shapes, for example, by etching the perimeter region of each member segment 302. For example, FIG. 8A shows an etched fiber segment 302 where the core region A5 is raised above the circumferential region A6 so that when heat is applied as described below, To form an etched member segment 802 which may be a more bent lens element 804.

In another embodiment shown in FIG. 8B, the etching of the member segment 302 is more sharp in the core region A5 and more sharp in the circumferential region A6 of the etched member segment 806. It may be raised to form a slope and may even result in a very curved lens element 808 when heat is applied as described below.

In one embodiment, the etching process described above may be performed by placing the ends 304, 306 into a hydrofluoric acid bath for a specified period of time. The acid bath affects the circumferential area A6 before it affects the core area A5, so that the longer the optically transparent members 302 are maintained in the HF acid bath, the more severe the etching. (I.e. the slope of the etched site becomes more urgent). Advantageously, optically transparent member segments with etched ends, for example, may form a lens with a shorter focal length and may improve light focusing.

As shown in FIG. 4A, the surface 308 or / and 310 of the array of optically transparent member segments 302 forming the sheet 300, etched or not etched, depends on the energy source. And may be heated to form the lens elements 406 forming the microlens array 400 (s108).

As shown in FIG. 9, heat treatment is performed so that the periphery region P1 of each member segment 302 softens or melts faster than the core region C1. do. Surface tension created by non-uniform melting causes curved surfaces to form at member segment ends that produce lens elements 904 and 906.

Heat treatment may be performed using any suitable heat generating means, including equivalents of the embodiments described herein. For example, referring again to FIG. 4A, in one embodiment, an array of optically transparent member segments 302 may be placed into a furnace 402. The furnace 402 allows heat treatment to be performed for all given optically transparent member segment materials. Heat treatment results in the formation of lens element 906 on surface 310 and / or the shape of lens element 904 on surface 308, if necessary.

As shown in FIG. 4B, in another embodiment, heat treatment is a wavelength that can be absorbed by an optically transparent member segment to heat the material and form the lens element 904 or / and 906. Can be performed by scanning the surface 308 or / and 310 with a laser 404 (ie, a highly powered laser). In another embodiment, the energy source providing heating may be a glow discharge located near the ends of the electrical spark / arc or optically transparent member segment or Or other known energy sources.

3B is a side view of a single optically transparent member segment 302 in accordance with an embodiment of the present invention. In this embodiment, the end 304 of the optically transparent member segment 302 can be modified by a heating process to have different radii of curvature in two mutually perpendicular or in different directions. The particular view of FIG. 3B is an end, such as a lens surface formed as an oval, semi-ellipse, flat / convex aspherical surface, etc., which can provide different optical performance with different optical axes relative to the major axis of the lens surface. The curved surface 308 is shown on 304.

In one embodiment, the end 306 may be made flat or modified to have different radii of curvature in two mutually perpendicular or in different directions. 3B shows the surface 310 bent on the end 306, such as an oval or semi-ellipse lens surface, which can provide different optical performance with different optical axes relative to the major axis of the lens surface. .

The pitch and size of the microlens array can be adjusted based on the requirements of the particular application. Fabrication usage and tolerances for microlens arrays are generally governed by a particular application and therefore may be specified by the end user.

In one embodiment, using the method according to an embodiment of the present invention, the microlens array uses standard single mode fibers having a diameter of about 125 μm, with at least 5% variation or non- It can also be made with uniform focal length.

5 illustrates an example of an application for a microlens array made using a method according to an embodiment of the present invention. Examples include a projection system 500 that may include multiple microlens arrays of varying size and shape designed for a particular application. In one embodiment, light enters the projection system 500 at a first end 502 having a first microlens array 504 having a first shape 506 such as, for example, a round shape. Light exits from the projection system 500 at the second end 508 via a second microlens array 510 having a second shape 512 such as, for example, a quadrangular shape. As will be appreciated from this example, the shape and size of the microlens array can be made as required for all applications by the methods described herein in accordance with one or more embodiments of the present invention.

Further, if necessary or required, the lens element 406 (FIG. 4A) of the microlens array 400 according to the embodiment of the present invention may be coated (s110). In one embodiment, for example for display screen applications, the microlens array 400 may be coated with an anti-reflection coating or / and an anti-glare coating. Coatings provided on the microlens array 400 are well known, such as sputtering, deposition, evaporation, spraying, dipping, spinning, rolling, and the like. Can be provided by technology.

As mentioned above in accordance with one or more embodiments of the present invention, the thickness t for the microlens array may also vary, as the number of lens sides and the size and shape of the lens surface may vary depending on the application or specification. Can be done. For example, FIG. 6A is a simplified diagram illustrating an embodiment of a microlens array 602 with lenses formed on both sides. The thickness t of the microlens array 602 may be made to any desired thickness, for example, a small thickness of thickness t between about 100 μm and about 1 mm, or a large thickness with a thickness t of 1 mm or more. have.

6B shows an embodiment of a microlens array 604 having lenses formed on both sides, but in this example the thickness t is considerably large (eg, greater than 1 mm). From this embodiment, it should be understood that the thickness t can be made to any thickness as required. 6C illustrates an embodiment of a microlens array 606 in which lenses are formed only on one side in accordance with an embodiment of the present invention. FIG. 6D is similar to FIG. 6C where the lens is formed only on one side, but surface 610 has a curved surface as described above.

One or more embodiments of the invention described herein are described for use as cylindrical, optically transparent members arranged in a bundle. However, those skilled in the art understand that the principles of the present invention are not limited to cylindrical shapes, but can also be applied to optically transparent members having other shapes, such as, for example, squares, squares or hexagons.

In accordance with an embodiment of the present invention, the microlens array may be employed, for example as a display screen, and provided as described herein. For example, the microlens array can be provided as described herein for method 100 (eg, s102-s110) and the performance of the microlens array when used as a display screen. Additional manufacturing processes are performed to improve the quality and quality.

For example, FIG. 10 provides a simplified view of the microlens array sheet 1000 of an optically transparent member segment 1002 in accordance with an embodiment of the present invention. For example, sheet 1000 may be formed in accordance with method 100 (eg, s102-s108) or formed by or including an alternative corresponding operation as described herein. Can be done.

Thus, for example, the sheet 1000 is formed by being sliced from optically transparent members or from a bundle of light rods (eg, the sheet 1000 has a roughly desired thickness). (t)), the sides 1004 and 1006 of the sheet 1000 are polished (or modified) to form a lens on respective ends of the optically transparent member segment 1002. It is heat treated. The sheet 1000 may be employed as a display screen or additional work may be performed on the sheet 1000 to improve the performance and quality of the sheet 1000 when used as a display screen.

By way of example, to block some of the light passing through one or more optically transparent member segments 1002 (ie, to block light around the lens periphery of each optically transparent member segment 1002). (light-shield layer) may be disposed on side 1004 or / and side 1006. A light shielding layer (eg, a black color layer) is deposited, adhered, provided, sprayed, or disposed on the side 1004 and / or side 1006 of the metal or sheet 1000. It may be another type of material. A light-shielding layer operation may be included as a step of method 100 (eg, s110 of method 100 of FIG. 1).

For example, FIG. 11 is a simplified side view of an optically transparent member segment 1002 having a light shielding layer 1102 provided in accordance with an embodiment of the invention. For example, the light shielding layer 1102 may be deposited entirely over the lens 1104 of the optically transparent member segment 1002 (eg, on the side 1004). Next, optically, for example, by other techniques, depending on the material used for the light shielding layer 1102 to remove etching or back-polishing or a portion of the light shielding layer 1102. The lens 1104 of the transparent member segment 1002 may then be partially exposed.

Thus, the lens 1104 may be partially exposed at, for example, the central or core portion of each lens 1104, but the light shielding layer 1102 is adapted to block light around the peripheral area of each lens 1104. Remains. Etching, back-polishing or other used techniques may flatten each lens 1104, as shown in FIG. 11. Thus, FIG. 11 shows a sheet 1000 (ie microlens array) with an integrated light shield. FIG. 11 is shown and the dimensions shown for the light shielding layer 1102 and the optically transparent member segments 1002 are exaggerated or distorted to aid in clarity and understanding one or more features of embodiments of the present invention. It should be noted that what may be shown as.

A coating (eg, thin film coating) may be provided on side 1006 or / and side 1004 of sheet 1000 after application of light shielding layer 1102. For example, reflection Thin film coatings such as anti-reflection coatings and / or anti-glare coatings may be provided on the side 1004 (eg, light output side). Silver may be provided to reduce reflection or / and glare and may be provided to protect the sheet 1000 (eg, from scratches or other damage) The coating may be provided as part of the method 100. May be provided (eg, s110 of method 100 of FIG. 1).

Various types of coatings, such as known to those skilled in the art, may be provided depending on the required results or the requirements of the application. For example, the coating material may be selected from SiO 2, Si 3 N 4 or TiO 2, or a combination thereof or from other conventional coating materials. For example, the selected coating material may be adapted to form a multilayer thin film coating configuration.

For example, with light shielding layer 1102 as described in connection with FIG. 11, sheet 1000 may be employed as a display screen as described herein. For example, FIG. 12 shows a simplified view of display screen 1200 in accordance with an embodiment of the invention. For example, the display screen 1200 may include a sheet 1000 having an optically transparent member segment 1002 and a light shielding layer 1102 (eg, around the lens periphery of the optically transparent member segment 1002). It includes.

Display screen 1200 may include a coating 1202 (eg, a thin film coating as described herein). For example, a sheet 1204 such as a Fresnel lens sheet may be included. Light passing through the display screen 1200 is provided to be seen on the other side as shown in FIG. 12. By using the techniques disclosed herein, the resulting output light (eg, the resulting light after passing through the display screen 1200) may have better quality or performance compared to conventional display screens.

As described herein, various embodiments of a microlens array are disclosed. For example, according to an embodiment of the present invention, a microlens array is disclosed so that it may be used to provide a high quality display means. Display screens are less expensive to manufacture than some conventional display screens. Furthermore, the display screen may provide improved performance compared to conventional display screens, for example in terms of brightness and uniformity, contrast or / and viewing angle.

The embodiments described above are not intended to limit the invention. It should be understood that various modifications and variations are possible in accordance with the principles of the present invention. Accordingly, the scope of the invention is only limited by the following claims.

Claims (31)

A method for fabricating a microlens array, the method comprising: Providing a bundle of optically transparent members, Cutting a bundle of optically transparent members to form one or more sheets of optically transparent member segments, Heating one or more sheets of optically transparent member segments to form individual bent lens segments on each optically transparent segment, Covering a portion of the one or more lens segments with a light-shielding layer. The method of claim 1, wherein the microlens array forms at least a portion of a display screen. The display screen of claim 2, wherein the display screen is a camera, a personal digital assistant, a telephone, a laptop, a computer monitor, a television, A method for fabricating a microlens array characterized in that it is part of a photocopy screen, projection screen or billboard. The method of claim 1, further comprising coating one or more lens segments. 5. A method according to claim 4, wherein the coating consists of an anti-reflection coating or / and an anti-glare coating. 10. The method of claim 1, further comprising providing a Fresnel lens sheet, wherein light passing through the lens segment is also passed through the Fresnel lens sheet. The method of claim 1, wherein the diameter of the one or more optically transparent members is different from some optically transparent members in a bundle of optically transparent members. 8. A method according to claim 7, wherein the diameters of the optically transparent members around the bundles are different from the diameters of the optically transparent members in the core area of the bundle. 10. The method of claim 1, further comprising modifying one or more ends of the optically transparent member segments. 10. The method of claim 9, wherein modifying comprises modifying both ends of the optically transparent member segments. The method of claim 1, wherein the providing comprises attaching optically transparent members to each other using an adhesive to form a honeycomb-like structure. Way for The method of claim 1, wherein the optically transparent members are made of glass, polymer or plastic. The method of claim 1, wherein the lens segments consist of convex, concave, or flat lens surfaces. 10. The method of claim 1, wherein heating comprises heating both ends of each optically transparent member segment to form a lens surface thereon. The method of claim 1, wherein the one or more sheets have a thickness between about 100 μm and 2 mm. And optically transparent members cut from the bundle of optically transparent members, formed of one or more microlens array sheets, and providing a pathway for light, wherein each optically transparent member is an optically transparent member. Has individual bent lenses formed on one or more ends of the A display screen disposed adjacent to the sheet and including a light-shielding layer that blocks a portion of the light passing through the respective optically transparent members 17. The display screen of claim 16, further comprising a thin-film coating covering the lenses of the one or more optically transparent members. 17. The display screen of claim 16, further comprising a Fresnel lens sheet, wherein light passing through the lens of one or more optically transparent members also passes through the Fresnel lens sheet. 17. The display screen of claim 16, wherein the display screen is a camera, a personal digital assistant, a telephone, a laptop, a computer monitor, a television, Display screen characterized in that it is part of a photocopy screen, projection screen or billboard 17. The display screen of claim 16, wherein the diameter of the one or more optically transparent members is different from the other diameters of the optically transparent members. 17. The display screen of claim 16, wherein the optically transparent members are made of glass, polymer or plastic. The display screen of claim 16, wherein the microlens array sheet has a thickness of between about 100 μm and 2 mm. A method for providing a display screen formed as a microlens array, the method comprising: Providing optically transparent cylindrical rods tied together to form a structure having a honeycomb-shaped cross section, Cutting a bundle of optically transparent cylindrical rods to form one or more sheets of optically transparent rod segments, each optically transparent rod segment having a first end and a second end and having light Is applied to the channel, Heating both ends to form a lens surface on the ends, and A method for providing a display screen formed as an array of microlenses comprising covering a portion of the lens surface on the first ends with a light-shielding layer. 24. The display of claim 23, wherein the display screen is a camera, a personal digital assistant, a telephone, a laptop, a computer monitor, a television, Method for providing a display screen formed as an array of microlenses, characterized in that it is integrated into a photocopy screen, projection screen or billboard. 24. The method of claim 23, further comprising providing a coating over the lens surface on the first ends. 24. The display screen of claim 23, further comprising providing a Fresnel lens sheet, wherein light passing through the optically transparent cylindrical rod also passes through the Fresnel lens sheet. How to provide 24. The display screen of claim 23, wherein the diameter of the one or more optically transparent cylindrical rods is different from the other diameters of the optically transparent members in the bundle. Way to do 24. The microlens array of claim 23, wherein said providing comprises attaching optically transparent cylindrical rods together using a UV curable adhesive to form a bundle. Method for providing a display screen formed as 24. The method of claim 23, wherein the optically transparent cylindrical rod is made of glass, polymer, or plastic. 24. The method of claim 23, wherein the lens surface consists of convex, concave or flat lens surfaces. 24. The method of claim 23, wherein the at least one sheet of optically transparent rod segments is between about 100 microns and 2 mm thick.

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