Diffusion Product that will De-Pixilate an LED Source

Abstract

The disclosed system is a method for manufacturing a film. The system comprises a computer, which has a microstructure design, and sends this design to a laser. The laser etches the design into a roller. The roller is then rolled over a liquid film to emboss the microstructures into the film. The film is then solidified to obtain a film with microstructures useful for diffusing light.

Claims

1. A system of manufacturing a light beam shaping diffusor comprising: a roller; a pattern of three dimensional microstructures directly ablated on to a substrate using a laser; and a liquid film material; wherein the substrate is attached to the roller; wherein the liquid film material is passed under the roller; and wherein after passing under the roller the liquid film is solidified forming a solidified film having the three dimensional microstructures embossed into the solidified film.

2. The system of manufacturing a light beam shaping diffusor of claim 1 wherein: each three dimensional microstructure is embossed 100 to 250 microns in the film.

3. The system of manufacturing a light beam shaping diffusor of claim 1 wherein, the pattern of three dimensional microstructures is generated by a computer and the pattern of three dimensional microstructures is displayed as an image file.

4. The system of manufacturing a light beam shaping diffusor of claim 3 wherein, the image file is converted from a text file indicative of three dimensional microstructures.

5. The system of manufacturing a light beam shaping diffusor of claim 3 wherein, the pattern of three dimensional microstructures etched onto the substrate provides a seamless roller.

6. The system of manufacturing a light beam shaping diffusor of claim 1 wherein, the liquid film is liquid polycarbonate.

7. A method of manufacturing a seamless diffusor comprising: creating a text file indicative of the desired structure of three dimensions of a set of microstructures; converting the text file into an image file; interpreting the image file, by a laser; laser etching the set of microstructures onto a substrate to create an ablated microstructure on the surface of the substrate; attaching the substrate to the roller running the roller along a surface of a liquid film; and freezing the liquid film such that the surface of the liquid film is embossed with the set of microstructures laser etched into the roller.

8. The method of manufacturing a seamless diffusor of claim 7 wherein; the roller provides a seamless set of microstructures.

9. The method of manufacturing a seamless diffusor of claim 7 wherein; the liquid film is a polycarbonate film.

10. The method of manufacturing a seamless diffusor of claim 7 wherein; the substrate is rubber.

11. The method of manufacturing a seamless diffusor of claim 7 wherein; the substrate is silicone.

12. The method of manufacturing a seamless diffusor of claim 7 wherein; the image file is a gray scale image, wherein the percent of the gray scale is indicative of a depth of a microstructure.

13. The method of manufacturing a seamless diffusor of claim 12 wherein; each pixel of the image file corresponds to a laser burn.

14. The method of manufacturing a seamless diffusor of claim 7 wherein; each microstructure is 50 to 250 microns deep in the film.

15. A light beam shaper comprising; a solidified film wherein a temperature at which the film was solidified is indicative of a gloss level on the surface of said film, a plurality of microstructures embossed into the film by a roller, wherein the microstructures are configured to diffuse and shape a beam of light, wherein the solidified film is reversible, such that when reversed the microstructures shape the beam of light into a different shape.

16. The system of manufacturing a light beam shaping diffusor of claim 2 wherein the three dimensional microstructures shape a beam of light into a round shape when a first face is facing the beam of light.

17. The system of manufacturing a light beam shaping diffusor of claim 16 wherein the round shape is a different round shape when a second face is facing the beam of light.

18. The system of manufacturing a light beam shaping diffusor of claim 1 wherein the roller contains a cooling liquid which solidifies the liquid film, wherein the temperature of the cooling liquid is indicative of a gloss level on the surface of the solidified film.

19. The system of manufacturing a light beam shaping diffusor of claim 1 wherein the liquid film material contains flame retardant additives.

20. The light beam shaper of claim 15 wherein the microstructures are embossed 100 to 250 microns into the film.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0013] FIG. 1 is a sample view of diffusion of light.

[0014] FIG. 2 is a perspective view of the system.

DETAILED DESCRIPTION

[0015] In FIG. 1 an up-close look at a beam shaping diffusor is portrayed. For a distance between microstructures, d less than about 8 microns, the visible light spectrum will have diffractive characteristics. The entrance beams 1 hit the micro structures 2. Upon hitting the microstructures, the beams are diffracted. The angle of incidence .sub.i, will determine the angles of diffraction .sub.m based on the energy of the light. If the distance between microstructures d is not great enough, the split in color will be visible. This can occur in parts of the structures as well as the entire structure.

[0016] The entrance light beams 1 will also refract when hitting microstructure 2. This refraction causes a change in the shape of the light beam. It is further possible to design the microstructures 2 such that when the entrance beams 1 move in from the opposite direction, different angles of refraction occurs, which over the entire array of microstructures would cause a different beam shape.

[0017] By creating a beam shaping diffusion structure that is considerably deeper than current diffusion structures available, the white light will still be diffused and refracted, but the diffusion structures will be far enough away from the diffraction or prismatic structures that the color fringing effects will no longer be visible. By solidifying the polycarbonate or other material film with the microstructures already embossed into them, it allows the film to retain its translucence and color shifting does not occur.

[0018] Creating microstructures with depths of about 50 to 250 microns is done through a roller. A computer designs the structures desired for each sheet of film, wherein the film is made of polycarbonate and/or other materials. The designs are ray traced in a computer program and optimized for the desired result. Each microstructure is designed at a unique angle at which it refracts the light. By selectively placing different angled microstructures throughout the film, a unique beam shape can be obtained. Further, due to the reversible nature of the film, a specific set of microstructures can be designed such that it creates a different beam shape when the film is reversed over the light source.

[0019] A text file is created with all of the geometry of the desired structure with X, Y and Z axes every few microns. These text files are then converted to graphic files in a separate, custom software program. The Z-axis values are converted from text files to gray scale files that the laser rip software can interpret. The Z-axis is defined as an intensity relative to the rubber being engraved to engrave to the proper depth (the desired depth from the software). The laser is then calibrated to keep the depth axis accurate relative to the gray scale file. A white pixel at 100% may indicate a depth (z-axis) of 150 microns, for example. According to this scale, a 50% gray scale will equal a depth of 75 microns. In other embodiments of the gray scale file, the relationship may not be linear. Each pixel represents a data point or laser burn. The laser can then ablate the rubber directly creating three dimensional shapes.

[0020] It is important to note that one of the advantages to this system of direct ablation is that the tooling cost is significantly less than traditional holography. It is also important to note that the rolls can be made without seams, which is impossible with holography. The relative costs of a large, stepped roll in holography are more than 20 the cost of the direct laser ablation. The holography will also always have shim lines or seams that can show up in the diffusion projection.

[0021] The computer then laser etches microstructures onto an intermediary, such as a substrate, which is attached to the roller. In other embodiments, the laser etches the microstructures directly onto the roller. Liquid polycarbonate, or other material, is passed under the roller, and the roller embosses these structures onto the material. When the material solidifies it retains these microstructures. This is further advantageous because by rolling the microstructures onto the film instead of etching or applying another material on-top, the polycarbonate film retains translucence.

[0022] One embodiment of the method of manufacture is portrayed in FIG. 2. In this embodiment, computer 20 sends a design of microstructures to laser 21. The laser embeds these microstructures onto the roller 22. These microstructures 23 may be inverse to what will appear on the polycarbonate film 24. As the polycarbonate film 24 is pushed under the roller by a mechanism 25, microstructures 26 are left on the polycarbonate film 24. As the polycarbonate film 24 is passed under the roller 22, it is in liquid form. This prevents solid on solid etching, which can cause damage to the top of the film, or otherwise ruin the translucence of the film. However, the polycarbonate film 24 is solidified with the microstructures 26 embossed into the film. Roller 22 may contain a cooling liquid or other source of cooling to accelerate the cooling process. By adjusting the cooling temperature of roller 22, the gloss level of the polycarbonate film 24 is adjusted.

[0023] In other embodiments of the invention, not all the components are necessary. In one embodiment, the rollers are premade and do not require a computer or laser etching. In another embodiment, the roller could be a stamp which embosses the entire film 24 at once. In another embodiment, the microstructures 23 are varied throughout the roller to create unique effects. Further, other materials besides polycarbonate may be used to compose the film, for example and acrylic or polyester.

[0024] In another embodiment, the roller is used on a polycarbonate that has already solidified. While this embodiment is not preferable, it could be done to simplify the manufacturing process. In a different embodiment, it is not the roller which directly causes the solidification, but instead, the system is designed to solidify the polymer simultaneously or about simultaneously with the roller entering the polycarbonate liquid. In some embodiments the film material is a gel, and solidifies over time. In other embodiments the roller can provide a cooling to the liquid film which allows the film to freeze with the microstructures intact. Other known methods of cooling the liquid film may also be used. By changing the temperature of the roller, or other cooling device, the gloss level on the surface of the solidified film will change. This allows customization to the gloss levels of the film depending on the desired outcome.

[0025] Solidification of the film while still in contact with the roller, or soon after ending contact with the roller is beneficial in helping to prevent the microstructures from morphing before solidification. In a similar fashion, the manufacture process could happen very slowly. For example, a small section of the liquid film under the roller at a given time, and upon that section's solidification the roller is then moved to the next portion of the film, until a desired length is achieved. In this embodiment, there may be a heat source on the liquid side of the film and a cooling source on the solidified section of the film.

[0026] In one embodiment, the microfilm is reversible for different effects. Facing the film with a first side against the light would lead to a greater transparency in the film, but with less diffusion. Facing a second side of the film against the light would lead to greater diffusion, but with less transparency. This embodiment allows the user to better customize the film for different purposes.

[0027] In a preferred embodiment, flame retardant additives are added to the polycarbonate film. Especially when exposed to light for an extended period of time, the polycarbonate has a chance to catch on fire. The flame retardant additives will prevent the polycarbonate from catching fire. In other embodiments, different additives could be added to the liquid polycarbonate. These could, for example, be dyes or other filter like effects, which change the filters overall effect on the light.

[0028] It should be understood to a person of ordinary skill in the art that different configurations of the transformer apparatus are possible. For example, the design layout of the transformer apparatus may differ from those shown in the Figures without departing from the scope and spirit of the present teachings.

[0029] While the present teachings have been described above in terms of specific embodiments, it is to be understood that they are not limited to those disclosed embodiments. Many modifications and other embodiments will come to mind to those skilled in the art to which this pertains, and which are intended to be and are covered by both this disclosure and the appended claims. It is intended that the scope of the present teachings should be determined by proper interpretation and construction of the appended claims and their legal equivalents, as understood by those of skill in the art relying upon the disclosure in this specification and the attached drawings.