JP2012514761A - Total reflection to switch flat panel display - Google Patents

Abstract

  Flat panel displays use pixels (2060) that are turned on or off by enabling or disabling total reflection (TIR) of the light guide (2010). The reflective surface (2070) points the light switched to the viewer. The optional mask provides a very high contrast ratio in low or high ambient lighting situations. Because of their small size and light weight, the TIR enabling element (2080) can be rapidly enabled, resulting in a very fast switching speed. With fast switching speed, colors can be generated and displayed in a continuous manner.

Description

Cross reference to related applications
[0001] This application is based on US patent application Ser. No. 12 / 319,171 “TIR Switched Flat Panel Display” filed Jan. 2, 2009, and US Patent Application No. filing Jan. 2, 2009. No. 12 / 319,172 claims “Optic System for Light Guide With Controlled Output”, each of which is incorporated herein by reference.
Technical field
[0002] The present invention relates generally to optical displays, and more particularly to flat panel displays in which light is switched by enabling and disabling total internal reflection (TIR), where the switched light is directed optically.

  [0003] Many products that display video, computers or other data require a flat panel display. Liquid crystal displays (LCDs) have become the dominant technology used in flat panel displays. Furthermore, the less common technology used for flat panel displays is the plasma technology. Another well known display technology used in thicker flat panel displays is of the rear projection type. For very large displays, a discrete array of LEDs is the dominant technology. These display technologies are used in products including many types of mobile phones, laptop computers, computer monitors, TVs, large commercial displays and billboards. Even if the performance of the newer technology is not significantly greater than the CRT, the dominant technology CRT type display has almost disappeared. Some current technology LCD displays still cannot meet the CRT refresh rate.

  [0004] Displays based on LCD technology have evolved for decades. Thousands of patents were applications for improvements to the basic technology. However, the performance of these displays is lacking in various ways.

  [0005] The first drawback of LCD display technology is high energy consumption. A diagonal 65 ”HDTV LCD TV generally halves about one kilowatt. This is a result of the low efficiency of the technology. LCD requires polarized light for function, but mostly generated by backlight Half of the light is absorbed in the creation of polarization.Many inventions have been devised to reduce this loss.In fact, the real most improvement is by reducing the product or other performance parameters for cost. One product that was designed without reusing light with the correct polarization was called ADBEF "manufactured by 3M of Minneapolis (MN).

  [0006] Another factor that contributes to the low efficiency of LCD displays is the fact that a pixel that is turned off absorbs light, rather than reflecting it relative to some other pixel.

  [0007] Another drawback of LCD displays is their limitations when used with color filters. In general, red, green and blue filters are used to create colors. These filters do not reflect unused light, but rather absorb it. For example, a red filter absorbs green and blue light while red light only passes through. In theory, a perfect blue filter will pass 33% of the light. In real filters, material is implemented significantly less than 33% of theory. Another place where light is absorbed is the matrix between the color filters. This matrix area is necessary for the circuit, and transistors are used to control the pixels. The required area is important in that one pixel requires three transistors, one transistor is needed for each of the three colors. Additional circuitry is also required to drive the transistors. The matrix area between the filters can absorb almost half of the total light available. When all of these and other losses such as reflection and material absorption are taken into account, the liquid crystal display panel only needs to be 8% efficient when all of the pixels move. In general, when creating an image of a pixel that is turned on, the image has approximately half and absorbs rather than reflecting with half of the pixels out of place, and the resulting LCD efficiency is only in the 4% range. is there.

  [0008] This low efficiency requires that the backlight used in LCD displays be large and powerful. The dominant lamp technology used in displays is fluorescent type lamps. These lamps are fairly efficient but require mercury. Mercury creates processing challenges. In many cases, mercury ends up in our food chain.

  [0009] Another drawback of LCD technology is the refresh rate. It is possible that only very recent LCDs are equal to the refresh rate of a CRT display. The slow refresh rate of the LCD is obvious to require applications like watching moving video. Another challenge with LCD is low contrast ratio. The contrast problem is exacerbated when viewed from a position away from the normal of the display surface.

  [0010] The quality of the color from a liquid crystal display is limited by the wavelength of light emitted from the light source and the characteristics of the color filter used in the display. Both of these factors result in a display that cannot accurately reproduce colors found in nature.

  [0011] Another drawback with LCD technology is its limited environmental coverage. Liquid crystal materials do not function well at high and low temperatures. Displays used in extreme environments are often cooled or heated to keep them within reasonable working range. Another challenge with using LCDs in non-optimal environments is that polarizing films required to reduce the quality of LCD displays when exposed to high humidity. Measurements are made to reduce the effect of this property. In displays used in extreme environments, the displays and their polarizing films are contained in a glass window.

  [0012] Plasma thin film panel display technology is a typical technology of choice for large screen TVs. Plasma displays are also a significant power consumption. Plasma TV does not last the same length of “on” experience as LCD TV. When a pixel remains for a long period of time, it happens to be on. These pixels lose their strength and become washed out over time. Cost is another issue with plasma technology.

  [0013] In TV applications, projectors are often deployed in a rear projection configuration. For computer monitors using a projection display, the front projection mode is more commonly used.

  [0014] Most rear and front projection displays utilize MEMS mirror arrays. MEMS mirror arrays are each disclosed in US Patent Nos. 4,566,935; 4,596,992; 4,615,595; 4,662,746; 4,710,732; 4,956,619 and 5,028,939, all filed by Texas inventor Larry Hornbeck and assigned to Texas Instruments (TI), Texas. Is done. TI technology uses an array of MEMS mirrors that change their angle of incidence into the optical path to change the light from out of position to the correct position. When the mirror is in the correct position, the mirror reflects the light so that it passes through the optical path. When the mirror is out of position, the light is reflected along a path deviated outside the projection optical system. This effectively turns the light valve off.

  [0015] It has many drawbacks with this technology. One is that optical transmission is less than 70%. In order to allow a change in the mirror's angular orientation, there must be a substantial clearance between adjacent mirrors. The essential clearance is wasted on much light. Further, the reflected light is absorbed by the light valve. The absorbed energy cools the switching device using this technique.

  [0016] Another flat panel display technology is disclosed in US Patent 5,319,491 by inventor Martin Selbrede of Thousand Oaks, California. This patent discloses a method in which the shape of the resilient membrane changes so that light can escape from the light guide. It is difficult to control the light output from the pixels, and therefore it is difficult to control the shape of the elastomer. The light output from the pixel depends on the angle at which the light strikes the film. The angle at which the light exits the panel is an angle away from the vertical. In general, the light perpendicular to the screen is the orientation you want the most output. The contrast ratio is limited by elastic membrane technology. This limitation is due to the fact that any fault of light or optics causes light to escape. When the display is mainly black, very small defects can cause sufficient light leakage to result in low contrast. In high ambient lighting situations, contrast is reduced by other factors. This factor is due to the reflection of malformed elastomers in some cases (environmental illumination for the viewer).

  [0017] Another flat panel display is disclosed in US Patents 6,040,937; 6,674,562; 6,867,896 and 7,124,216 by inventor Mark Miles of Boston, Massachusetts. The present invention controls the distance between the optical elements to control the interference characteristics of the pixels. This technique is effective for reflection mode and is therefore effective for application to most display applications. Three light switches need to create red, green and blue colors. Not only is a three-color optical switch required, but the electronics that move the switch must also be included.

  [0018] Other display inventions were recently disclosed in both US Patent Publications 20050248827 and 20060070379 by WA inventor Gary Starkweather, which were assigned to WA Microsoft. This technique is similar to the Hornbrook technique in that it switches light by bending or moving the mirror. This technology suffers because of its high complexity and high cost. The effect of this technique is that its theoretical efficiency is better than most other techniques. However, as a practical matter, the technology requires a collimated backlight source. This type of source is inefficient and expensive. The cost of displays with this technology is high and still inefficient. Furthermore, the creation of a collimated backlight source requires that a considerable depth exists in the display. This depth is undesirable for consumers and therefore reduces the market for this technology.

  The present invention uses micro optical components. Some prior art related to this field must also be discussed. US Pat. No. 6,421,103 (assigned to Fuji Film) by Yamaguchi Chira in Japan discloses a backlight for a liquid crystal display panel. This patent discloses a light source, a substrate, an aperture (not used as a light guide) and a reflective area on the substrate. The light is reflected by the surface of a certain reflecting surface and passes through the opening. Light passing through the aperture is captured by the lens and used to control the direction of the light. The Yamaguchi reference teaches that liquid crystal type display viewers concentrate directly on more light at a limited angle of light.

  [0020] US Pat. No. 5,396,350 by Carl Bieson of Princeton (New Jersey) discloses a light guide having an optical element used to extract light from the light guide. The optical element is on the viewer side of the panel and limits its ability to control the direction of light. It is an object of the present invention to be used in conjunction with an LCD type control panel in order to concentrate light toward the viewer.

[0021] The present invention is a light valve used in a thin flat panel display.
Flat panel displays are used in cell phones, laptop computers, computer monitors, TVs and commercial displays. The light valve of the present invention allows light to be extracted and the light to travel over the light guide by the TIR process.

  [0022] The light is first emitted from the end of the light guide to the light guide. The light then travels over the light guide by reflecting off the inner surface of the light guide. When light arrives at the top of the light guide, the reflective material reflects back to the light toward the bottom of the light guide.

  [0023] As light travels up and down the light guide, the light typically contacts the light guide to find a point where the elements of the TIR switch are in the correct position. When the switch element contacts the light guide, light is extracted from the light guide and directed to an optical system that redirects the light to the viewer. Switch elements that are not in contact with the surface of the light guide do not extract light. A contact switch produces an “on” pixel, while a switch that is not in contact with the light guide produces an “off” pixel.

  [0024] Additional optics and masks can be added to a given system to improve contrast ratio, viewing angle, and other parameters that are important to the display viewer. By alternating light colors and switching pixels in sequence, a full color display can be generated with a minimum number of switches. When a full gamut of colors is supplied to the light guide, the colors can be presented to the viewer without filtering by successive switching.

[0025] An advantage of the present invention is that it enables use of flat panel displays that have much greater decisions than current technology devices.
[0026] Another advantage of the present invention is that the technology is easily manufactured in flat panel displays.

[0027] A further advantage of the present invention is that the device can switch faster and better than the prior art, which requires very little movement of the optical system to achieve switching.
[0028] Yet another advantage of the present invention is that it provides a higher contrast ratio with better color reproduction.

[0029] Yet another advantage of the present invention is that the display performs well in non-ideal environments.
[0030] As illustrated in the drawings and as described herein, these and other objects and advantages of the present invention will be derived from the description of the most well-known method of carrying out the invention. It will be apparent to those skilled in the art.

[0031] FIG. 1 shows a perspective view of a thin flat panel display with TIR switching technology. [0032] FIG. 2 is an exploded view of the display shown in FIG. FIG. 3 is an enlarged portion of the lower left corner of the display shown in FIG. 1, with the display rotating from vertical orientation to horizontal position. [0034] FIG. 4 is a top perspective view of the electronics back panel component of the TIR display. FIG. 5 is a bottom perspective view of the back panel component shown in FIG. FIG. 6 is a detailed view of the film components of the TIR display shown in FIG. [0037] FIG. 7 shows a film component assembled with an electronic back panel component. [0038] FIG. 8 is an enlarged side view of a film component spaced apart from an electronics back panel component. FIG. 9 is a side view of the flat panel display. Some components of the display are not shown for clarity. [0040] FIG. 10 shows a side view of the display along with several included ray traces. [0041] FIG. 11 shows a side view of the display with the TIR light valve turned off and several ray traces included. FIG. 12 is a reduced cross-sectional view of the light guide, the LED, and the light guide reflector. [0043] FIG. 13 is a side view of a flat panel display having all of the illustrated display components. [0044] FIG. 14 is a perspective view of a small portion of the black mask. [0045] FIG. 15 is an enlarged side view of a TIR switch with the film components and the electronics back panel assembled together. [0046] FIG. 16 is a block diagram of the control electronics required for the color sequence. [0047] FIG. 17 illustrates a flat panel display utilizing piezoelectric or electroelastomer elements. [0048] FIG. 18 shows a flat panel display with fixed reflectors. [0049] FIG. 19 shows a flat panel display with a hollow fixed reflector. [0050] FIG. 20 illustrates an embodiment of the technique. [0051] FIG. 21 illustrates an embodiment of the technology. [0052] FIG. 22A illustrates an opened window. [0053] FIG. 22B illustrates a closed window.

  Referring first to FIG. 1, the TIR switched thin flat panel display 1 of the present invention has a panel region 2. In the panel area 2, the green LED 3, the blue LED 4 and the red LED 5 are located along the lower edge. The number of LEDs 3, 4, 5 and the side on which they are located is a function of size, shape and use of the desired display. EDs 3, 4, and 5 can be placed on one or more edges, and specific applications need it. LEDs 3, 4, 5 require driver electronics to drive them at the appropriate level and at the appropriate time. One skilled in the art of LED driver electronics can devise many different circuits to accomplish this task. In the embodiment illustrated in FIG. 1, 27 LEDs 3, 4, 5 are shown generally equally spaced along the bottom edge. With its high efficiency inherent in terms of TIR technology, this multi-LED display is intended for outdoor use of bright ambient light. A display intended for use in low ambient light requires fewer LEDs 3, 4, and 5.

  [0055] FIG. 2 is an exploded view of the panel region 2, which consists of four main components. A mask and diffusion assembly 6 forms the front layer of the panel region 2. The light guide 7 is behind the mask and diffusion assembly 6. The TIR switch film 8 is behind the light guide 7. The electronics back panel 10 is behind the switch film 8. All four of the main components 6, 7, 8, 10 have the same area as the area 11 of pixels. The number of pixels required depends on the display resolution.

  [0056] The four parts 6, 7, 8, 10 (shown in exploded form in FIG. 2) are joined together in use as shown in FIG. The small corner cross section of the combined assembly is shown greatly in FIG.

  In FIG. 3, the green, blue and red LEDs 3, 4, 5 show their true relationship with the light guide 7. The end reflector 9 covers the same edge of the light guide 7 as the LEDs 3, 4, 5. (The reflector 9 is shown in more detail in FIG. 12, the function of which will be described later.) The relative thicknesses of the main components 6, 7, 8, 10 are shown in FIG. The relative thickness of the main components 6, 7, 8, 10 varies for different sizes and pitches of a given display.

  [0058] Referring now to FIG. 4, the electronics back panel 10 is shown in the same direction as FIG. The substrate material for the electronics back panel 10 must be a shielding material. For larger displays, fiberglass reinforced PCB materials and the like are desirable as substrates. For smaller displays, the insulating substrate material may be glass, silicon or plastic. Since the substrate material does not need to be optically transparent, there are many options for material selection.

  [0059] Electronic components may be placed on the flat surface 21 of the electronics back panel 10. For clarity, none of those components are shown in FIG. The annular ring 22 is located near the center line of the pixel area. The annular ring 22 may be made of a conductive material and is generally thin. The annular ring pocket 23 is a recessed area for clearance from optical components (described below). The annular ring pocket 23 may also be made of a conductive material and is thin. If the electronics are behind the electronics back panel 10, at least one supply through hole 24 is necessary. The supply through hole 24 is shown concentric with the annular ring 22, but concentricity is not essential. The supply through hole 24 can be located anywhere on the electronics back panel 10. The supply through hole 24 has a thin layer of conductive material that connects the annular ring 22 to any electronic equipment that is behind the electronics plane 10. It should be noted that any electronic components such as transistors, capacitors or resistors that are necessary for the subject display application can be placed between the annular rings 22 or below the surface of the electronics back panel 10 There is.

  [0060] Referring now to FIG. 5, the supply through hole 24 is visible on the back side of the electronics back panel 10. FIG. The bottom annular ring 25 is formed from a thin layer of conductive material to provide electrical conduction to the supply through hole 24. Circuit wiring 26 is used to connect bottom annular ring 25 to circuitry located elsewhere on the back of the board. In another embodiment, the annular ring 25 can be connected to an electrical connector, which communicates with other electronic components to attach the annular ring 25 to the remote PCB. Those skilled in the art of electronic layout and manufacturing can easily determine the placement and type of appropriate electronic equipment to reduce overall system cost while improving performance.

  [0061] A TIR switch film 8 is shown in FIG. The TIR switch film 8 is made of a transparent flexible type material (for example, polycarbonate, polyester, acrylic resin, etc.). The upper surface 31 of the TIR switch film 8 is located near the surface of the light guide 7 (not shown in FIG. 6), but there is a narrow gap between the upper surface 31 of the switch film 8 and the surface of the light guide 7. is there. The contact dome 32 is ideally located in the center of the pixel area. (The contact dome 32 can be seen in more detail in FIG. 8.) The contact dome 32 preferably has a flat area and a shallow slope on the top surface. The flat region can be formed to match (ie, match) a corresponding portion of the light guide. For a very short For dome 32, the dome 32 has no gradient at all. (A contact dome without a gradient has the advantage that it can be formed by a lithographic process. An A dome with a tapered side is best formed by a casting method.) Each of the contact dome 32 Includes a reflector periphery 33. Since the TIR switch film 8 is transparent, the reflector periphery 33 is located on the back side of the switch film 8 but is visible in FIG. The TIR switch film 8 is very thin to allow easy bending. The thickness of the switch film 8 is smaller than 1/10 of the diameter of the reflector peripheral portion 33.

  The spacer post 34 is composed of another main element of the TIR switch film 8. Spacer posts 34 are located between the contact domes 32. The spacer post 34 maintains a narrow gap 60 (visible in FIG. 15) between the switch film 8 and the light guide 7. Although the spacer posts 34 are illustrated in FIGS. 6-8 as being square, other shapes may be used as well. The spacer post 34 extends downward from the bottom surface through the switch film 8 to form a lower spacer post 34 '. The lower spacer post 34 'is most easily seen in FIG.

  FIG. 7 shows the TIR switch film 8 assembled to the electronics back panel 10. An annular ring 22 on the electronics back panel 10 can be seen through the transparent TIR switch film 8. The center line of the pixel features of the TIR switch film 8 and the electronics back panel 10 are located throughout.

  FIG. 8 shows an exploded cross-sectional side view of the electronics back panel 10 and the TIR switch film 8. The annular ring pocket 23 is shown in FIG. 8 in a spherical shape. The shape of the annular ring pocket 23 may be rectangular, trapezoidal or irregular. The shape of the ring pocket 23 does not affect the optical function of the present invention. The reflector 35 is received in the ring pocket 23. The shape of the reflector 35 is generally represented as a sphere, which is a reflector shape that is acceptable for many applications. However, for most display applications, the ideal shape for the reflector 35 is aspheric. The particular optimal aspheric shape of reflector 35 is a function of dome diameter, dome gradient, dome position with respect to the aspheric reflector, the refractive indices of the various components, and the diameter of reflector 35. Moreover, the manufacturing method of the reflector 35 can have a practical influence on the shape selected for the reflector 35. Those skilled in the art of reflector design can devise reflector shapes to address specific design goals for a given overall display.

  The lower spacer post 34 ′ is formed from the lower end of the spacer post 34. The bottom surface of the lower spacer post 34 'contacts and is bonded to the flat surface 21 of the electronics back panel 10. The upper surface of the spacer post 34 is bonded to the light guide 7. The adhesive for this bond must have a low refractive index. If the adhesive has a too high refractive index, the coupling surface of the light guide 7 will need to be coated with a low refractive index material. FIG. 9 shows the TIR switch film 8 coupled to the light guide 7. The contact dome 32 is in contact with the light guide 7. In the case where the light guide 7 is coated with a low refractive index material, the region where the contact dome 32 contacts the light guide 7 needs to have the low refractive index material removed.

[0066] Referring now to FIG. 10, light ray 41 originates from green LED 3. The light beam 41 is reflected from the film side surface 42 of the light guide 7. This reflection of ray 41 is total internal reflection (TIR). The ratio of the refractive index ANs (R) of the material adjacent to the surface of the light guide to the refractive index ANIg "of the light guide material (angle AA @) from the perpendicular to the film side 42 to the ray direction (angle AA @) TIR occurs when less than the arc sine of the quotient) For the case where the light guide is made of acrylic resin and adjacent material is air, the angle A is: where Ns = 1 and NIg = 1.5
Angle A = arcsine (1 / 1.5) = 41.8 [degree]
It may be. When the internal angle A is less than 41.8 degrees, the light is reflected from the internal surface. If the angle A is greater than 41.8 degrees, the light passes through the surface and is refracted at different angles.

[0067] There are three cases where different materials are adjacent to each other, and the angle A is different for all three, and they are as follows:
Case 1 has light guide (refractive index 1.5) adjacent to air (refractive index 1) Case 2 has light guide (refractive index 1.5) adjacent to contact dome (refractive index 1.5) Case 3 If the light guide (refractive index 1.5) is adjacent to a low refractive index material (refractive index 1.35), calculating the angle A for these three cases: A = arcsine (Ns / NIg)
Case 1: When Ns = 1, NIg = 1.50 A = arcsine (1 / 1.50) = 41.8 degrees Case 2: When Ns = 1.50, NIg = 1.50 A = arcsine (1.50 / 1.50) = 90 degrees Case 3: Ns = 1.35, NIg = 1.50 A = arcsine (1.35 / 1.50) = 64.2 degrees
[0068] From these three calculations it appears that the light 41 continues to be reflected under the light guide 7 when the approach angle of the ray 41 is less than 62.5 degrees from normal to the surface of the light guide 7. Case 1 and Case 3 are cases where the light is TIR. In Case 2, the light does not TIR. The light travels along the original path through the surface of the light guide 7 and through the contact dome 32.

  [0069] It should be noted that the light guide 7 and the contact dome 32 cannot have the same refractive index. If the refractive indices are not equal, some refraction occurs at the interface of the light guide 7 and the contact dome 32. The difference in refractive index between materials determines the amount of refraction. Preferably, the refractive index of the contact dome 32 is greater than that of the light guide 7. If the refractive index of the contact dome is smaller than that of the light guide 7, some light traveling at an angle greater than normal to the surface of the light guide 7 will not pass through the contact dome 32.

[0070] Three types of angles A in FIG. 10 are correlated:
The reflection off the film side 42 using the air refractive index is the first TIR reflection of the ray 41. This reflection is combined by the case 1 equation. The low refractive index TIR reflection 44 is the TIR reflection of the second ray 43 and is combined by the case 3 equation. The third internal ray 45 strikes the adapted refractive index point 46 and does not experience TIR. It is assumed that the ray 45 passes through the light guide 7 and contacts the material of the dome 32 without reflection, and the contact dome 32 contacts the light guide 7 when the ray 45 hits this point. It should be noted that the joint must be free of gaps. Even small air gaps disrupt the passage of light. Small gaps can be created by small changes in surface finish or even small foreign particles. The addition of a thin layer of transparent elastic material on the surface of the light guide 7 or the surface of the contact dome 32 ensures that no light is confused and that light passes as required.

  [0071] The light ray 45 continues beyond the contact dome 32 and reflects off the surface of the reflector 35. The reflector 35 is preferably coated with a high reflectivity material (eg, aluminum, silver or a dielectric coating). The contour of the surface of the reflector 35 determines the direction of the reflected light 48. As described above, the contoured reflector 35 is preferably aspheric in shape.

  FIG. 11 shows the same elements shown in FIG. 10, but in FIG. 11, the contact dome 32 is not in contact with the light guide 7. When the contact dome 32 is not in contact with the surface of the light guide 7, the refractive index of the surface of the light guide 7 is that of air. Under these circumstances, case 1 glows with a TIR off the surface of light guide 7. The light beam 49 continues TIR along the interior of the light guide 7 until the light beam 49 contacts the light guide 7 and strikes the contact dome 32. In summary, when the contact dome 32 associated with a particular pixel contacts the surface of the light guide 7, that pixel is in the on state. When the contact dome 32 is not in contact with the light guide 7, the pixel is off.

  [0073] FIG. 12 shows an enlarged side view of the light guide 7, LED 3 and end reflectors 9 and 9 '. The end reflectors 9, 9 'are preferably formed from a material having a high reflectivity. The end reflector 9, 9 ′ may be an interference type or a reflector, or the reflector 9, 9 ′ may be a bent retro type reflector.

  [0074] Light often travels the length of the light guide 7 from the LED 3 and does not strike the contact dome 32 in the on position. The light is therefore not extracted from the light guide 7 in a TIR. In this case, the light continues to travel along the entire length of the light guide 7 until it reaches the end of the light guide 7 and is reflected off the end reflector 9 =. This reflection redirects the light in the rear in the opposite direction through the light guide 7. The light then travels back along the length of the light guide 7, and disguising it is active when the dome 32 returns to the first end of the light guide 7 (the end where the LEDs 3, 4, 5 are located). Do not turn.

  [0075] At the first end, the light hits the region between the LEDs 3, 4, 5 or it hits the LEDs 3, 4, 5. When the illumination hits the area between the LEDs 3, 4 and 5, it is reflected by the end reflector 9. If the TIR flat panel display 1 is equipped with only a few LEDs 3, 4, 5, the light is mostly reflected away from the high reflectivity end reflector 9. In some cases, the light reflects away from the LEDs 3,4,5. LEDs 3, 4, and 5 absorb some light, and the remainder of the light is reflected. The light can travel up and down the light guide 7 many times before it is extracted by the contact dome 32. This is the case when only a few contact domes 32 move and draw light. When many of the contact domes 32 are in contact with the light guide 7, the possibility of light being designed to make one or more paths along the light guide 7 is small. Even when there are a large number of reflections and the light takes a number of passes along the light guide 7, the loss of light is small. The end reflectors 9, 9 'can have a reflectivity efficiency of 98%, or a better and better quality light guide will absorb very little light.

  Referring to FIG. 13, the mask and diffusion assembly 6 is mounted above the panel region 2. A multilayer assembly comprising a mask and diffusion assembly 6, a low refractive index layer 51, a spacer plate 52, a mask plate 53, a first diffuser 55, a second spacer 56 and a second diffuser 57.

  [0077] The low refractive index layer 51 is thin and has a low refractive index. Although an air gap or vacuum layer can serve as the low index layer 51, it is often beneficial to assemble the device to form the low index layer 51 from a low index solid material. The low refractive index layer 51 is typically an adhesive that attaches the spacer plate 52 to the light guide 7. In applications that require very thin displays, the low index layer 51 and spacer plate 52 can be combined into one element (the thicker low index layer 51). However, for larger displays, the use of two different materials that form the low index layer 51 and spacer plate 52 is more beneficial.

  [0078] Two thin layers (mask plate 53 and first diffuser 55) are located between spacer plate 52 and second spacer 56. The mask plate 53 includes a number of apertures 54 (see FIG. 15) so that the reflected light 48 can pass through the mask plate 53. The remaining area of the mask plate 53 is preferably a black material with a high absorption rate. Black chrome, carbon black or organic materials are materials that serve as suitable materials for the three types of mask plates 53. When there is ambient lighting, the mask plate 53 increases the contrast ratio of the display. The mask plate 53 absorbs light that would otherwise be reflected from the TIR switch film 8 or any of its components. For an inexpensive display, the mask plate 53 can be removed where cost is more important than quality. Also, the mask plate 53 can be removed if the display is only used in low ambient lighting situations. An embodiment of the low ambient lighting environment is a movie theater.

  [0079] The first diffuser 55 is an arbitrary diffuser that spreads the light coming from the reflector 35. For small displays, the first diffuser 55 is not necessary, but for displays with large pixels, the first diffuser 55 must be included. It must also be emphasized that the position of the mask 53 and the first diffuser 55 could be reversed without affecting the function of the display.

  The light transmitted from the reflector 35 can begin to spread by the second spacer 56. The second diffuser 57 is also used to further spread the light so that the viewer may be in a position that is not perpendicular to the display and still see the light from the reflector 35. The amount and direction of diffusion incorporated into the second diffuser 57 will vary for different types of displays. For example, small cell phone displays generally have fewer viewing angles in both vertical and horizontal directions. A TV typically has a large viewing angle in the horizontal direction, and a vertical viewing angle is not large.

  Referring to FIG. 15, the TIR switch film 8 is assembled to the electronics back panel 10. There is a small air gap 60 between the electronics back panel 10 and the switch film 8 maintained by the spacer posts 34. The annular ring 22 of the electronics back panel 10 is proximal to the bottom surface 36 of the TIR switch film 8. The bottom surface 36 is covered with a conductive layer 62. For ease of fabrication, the conductive layer 62 may be a continuation of the surface of the reflector 35. An electrostatic force is created when the conductive layer 62 and the annular ring 22 are electrically filled. When the charges are in like polarity, the surfaces repel each other. When the charges are of opposite polarity, the surfaces are attracted to each other. Thus, by controlling the relative charge of these surfaces, the conductive layer 62 and the annular ring 22, the contact dome 32 can be applied or the surface of the light guide 7 (not shown in FIG. 15) Can be removed from contact with. To prevent the two charged surfaces from being shorted, either one or both of the charged surfaces are coated with an insulating layer.

  [0082] It should be noted that electrostatic forces are not the only means used to control the contact between the surface of the light guide 7 and the contact dome 32. One alternative is the ability to use piezoelectric materials. Another is to use magnetism. Those skilled in the art of actuators can devise many ways to change the position of the contact dome 32. In addition, there may be electronic circuitry that can be devised to drive an unlimited number of actuators.

  [0083] FIG. 16 represents a schematic diagram of a circuit used to create color with pixels. In order to create a green image for the viewer at pixel n, m, the switch for pixel n, m moves to a state with contact dome 32 in contact with light guide 7 and for green LED 3 The driver is turned on. The blue and red LEDs 4, 5 are not on. (If the display is only producing a black and white image, there is one exception to this case. Then all three LEDs S3,4,5 are on at the same time, or white LEDs are The contact dome 32 associated with the pixels n, m can be used for a suitable period of time so that the desired amount of light can produce the desired intensity for the viewer to exit the creating pixel. Remains in contact with the light guide 7 between. To make a blue display, the contact dome 32 is placed in contact with the light guide 7 when the blue LED 4 is on. The contact dome 32 remains the contact that the amount of time needed to create a particular strength needed for the viewer. The red color is created in a similar way. To create the second color or white, the contact dome 32 is placed in contact with the light guide for two or more periods when two or three of the LEDs 3, 4, 5 are on.

  [0084] For example, to create a yellow image with pixels, the contact dome 32 draws light from the light guide 7 when the red LED 3 is on. After red LED 3 disappears, blue LED 4 turns on. When the blue LED 4 is on, the contact dome 32 does not extract light. After the blue LED 4 is turned off, the green LED 5 is turned on. When the green LED 5 is on, the contact dome 32 allows light to reach the viewer again. This incorporates red and green into yellow, and the human eye results in hundreds of seconds. The brightness is determined by the length of time that light can reach the viewer through the contact dome 32. By changing the individual times for red and green, the yellow tint can be controlled. Some blue light can be added to reduce yellow saturation.

  [0085] It should be noted that LEDs generally do not emit a wide range of wavelengths of light. A high resolution display can include LEDs having a wavelength between the main RGB LEDs. Embodiments are orange, cyan and yellow. By adding these extra wavelengths, the spectral output of the TIR display could be performed to find one that fits the real world for viewing by the viewer. Very little additional circuitry is not required to add this improved performance.

  [0086] It must also be noted that the electronics need to control the switches and LEDs of the present invention. Electronic equipment also requires that the operation of the optical element be associated with a computer, TV, or other type of video signal. This type of control electronics is made for display systems that create colors by multiplexing the colors in time. One skilled in the art can devise many ways to accomplish this task. The innovative part of the present invention is that it is an optical switch rather than an electronic component configuration.

  [0087] FIG. 17 illustrates an apparatus using piezoelectric material 70 as the actuation mechanism. This embodiment reveals the operation in which the material 70 is attached to the reflector surface 35. As used to drive the electrostatic force switching mechanism, the piezoelectric material 70 is driven with the same type electronics backplane 10. By changing the height of the piezoelectric material 70, the reflector surface 35 and the contact dome 32 can therefore be turned on / off.

  [0088] Another configuration of the device is shown in FIG. 18, which shows a contact dome 32 resting on an angled cone 80 on the elastic switch film 8. This configuration is preferred when the reflector size is large. The reflector is stationary and has an area 82 that is more relaxed than the slightly angled cone 80 and has a cone angled to the switch film 8. The relaxed region 82 can move in contact with the light guide 7 and away from the light guide 7 by clearance with the contact dome 32 and the angled cone 80.

[0089] FIG. 19 illustrates the configuration of the device, where the reflector region 35 ′ is free of material and is air or vacuum. The reflector area 35 'is still used to reflect light.
[0090] FIG. 20 illustrates an embodiment. The light 2000 can be transmitted by the light guide 2010. The light guide 2010 can have a first refractive index, and one or more media between the light guide 2010 and another medium (eg, solid, liquid, air or vacuum) having a second refractive index. A surface can be included. The surface may be substantially planar, curved, elongated (eg, with dimensions such that one dimension is 10 or 100 times greater than the other dimension), and other shapes . The light guide 2010 includes a first surface 1020 configured to receive light from a light source (not shown), a second surface 2030 (eg, light can exit the light guide 2010), and a contact dome And a third surface 2040 associated with various light control devices, such as windows. The light guide 2010 can include one or more fourth surfaces 2050. In some cases, the fourth surface 2050 can receive light from a light source. In some cases, the fourth surface 2050 can be at least partially reflected. In certain embodiments, the fourth surface 2050 can include a fully reflecting mirror, which returns the light into the light guide 2010 and directs incident light on the fourth surface 2050 from within the light guide 2010. Can be reflected.

  [0091] The light guide 2010 can be characterized by one or more lengths (eg, length 2012 and thickness 2014). The length can be selected according to various application specifications (eg, mobile phone screen, home lighting form factor, TV size, etc.). The length can be selected according to various material properties (for example, thickness 2014 is the refractive index of the light guide 2010, the angle associated with the TIR of the light guide 2010, the specifications regarding the quality of the light emitted from the light guide 2010 ( For example, the light requirement can be selected by the second surface 2030 within a standard range of a few degrees), and the like.

  [0092] Light from the light source may be transmitted to the light guide 2010 by the first surface 2020. The first surface 2020 can be at least partially reflective (eg, a half mirror) to return into the light guide 2010 and reflect light reaching the first surface 2020 from within the light guide 2010. Can be configured. The first surface 2020 may be flat, curved or other shape. The first surface 2020 may be disposed at an angle 2022 with respect to one or more other surfaces of the light guide 2010. The angle 2022 may be between 45 and 135 degrees, between 70 and 110 degrees, and / or between 80 and 100 degrees. In some cases, angle 2022 can be selected by various predicted angles of internal reflection within light guide 2010.

  [0093] Light from the light source may be sent to the light guide 2010 by the fourth surface 2050. The fourth surface 2050 can be at least partially reflected (eg, a half mirror) and returns light into the light guide 2010 to reach the fourth surface 2050 from within the light guide 2010. Can be configured to reflect. The fourth surface 2050 may be flat, curved or other shape. The fourth surface 2050 may be disposed at an angle 2052 with respect to one or more other surfaces of the light guide 2010. Angle 2052 may be between 45 and 135 degrees, between 70 and 110 degrees, and / or between 80 and 100 degrees. In some cases, angle 2052 can be selected by various predicted angles of internal reflection within light guide 2010.

  [0094] A surface (eg, the first surface 2020 and / or the fourth surface 2050) returns into the light guide 2010 in one or more suitable directions (from within the light guide 2010 to the surface). It can be configured to reflect (incident) light. In some cases, the surface can reflect light in a manner that minimizes unwanted transmission of reflected light from the light guide 2010. In certain cases, light can be reflected from other surfaces (eg, second surface 2030 and / or third surface 2040) at an angle that is less than the angle of incidence associated with TIR.

[0095] Some surfaces (eg, the third surface 2040, and / or the optional second surface 2030) have reflections that depend on the angle of incidence of the incident light (eg, from within the light guide 2010). Mirror "can be included. The angular dependence of reflection can be generated via refractive index control on both sides of the surface. The angular dependence of reflection can be created through other methods, such as nanostructuring methods such as surfaces, surface coatings and the like. In some cases, the surface is designed to reflect incident light at a low angle of incidence (eg, 45 degrees or less, 30 degrees or less, 20 degrees or less, or even 10 degrees or less). In some cases, incident light at a large incident angle (eg, perpendicular to the surface, within 2 degrees from vertical, within 5 degrees from vertical, within 10 degrees from vertical, and / or within 20 degrees from vertical) The surface is designed to pass.
be able to.

  [0096] The surface of the light guide 2010 can include one or more windows 2060, which can be opened and closed via various actuation mechanisms. Thus, the window 2060 can behave as a light valve. In the embodiment shown in FIG. 10, the window 2060 is located on the third surface 2040 and the light exits the light guide 2010 via the second surface 2030. Some embodiments include dozens, hundreds, thousands, millions or even hundreds of millions of windows 2060. Certain embodiments include one, two, three, five or ten windows 2060. The window 2060 can be characterized by one or more dimensions 2062 (eg, length, width, radius, and / or other dimensions that characterize various aspects of the window 2060). The window 2060 can be characterized as “transparent” for substantially all incident light, and other structures (eg, contact dome, reflectors, etc.) can be within the “body” of the light guide 2010. Transmission of light from can be allowed. The window can be created by bringing a contact dome into contact with the surface. The open window can allow light to pass through the contact dome, which can be reflected by a reflector. By removing the contact dome (creating a gap), the window can be “closed” to the passage of light.

  [0097] The reflector may have various shapes (parabolic, elliptical, straight, curved, flat, other shapes). There may be different reflectors in the window associated with different directions of incident light. For example, the shape of the reflector 2070 can be selected by preferential reception of incident light from the direction associated with the first surface 2020. Window 2060 provides light passage through the window to one or more reflectors. In the embodiment shown in FIG. 20, the reflector 2070 is arranged at a position where incident light should be reflected. The reflector may generally be a perfect mirror (eg, full and / or specular). The reflector can be characterized by one or more dimensions. In the embodiment shown in FIG. 20, the reflector can be characterized by dimensions 2074 and 2078, and can optionally be characterized by other dimensions (eg, perpendicular to the page).

  [0098] In the embodiment shown in FIG. 20, the third surface 2040 functions as an angle dependent mirror via reflections induced by different refractive indices on both sides of the surface. Such an implementation can include a reflector 2070 disposed on a contact dome 2080 made from the same material as the light guide 2010. The contact dome can be actuated by an actuator (not shown) to move in direction 2090, providing an opening (contact light guide 2010) and closing via actuation of contact dome 2080 in direction 2090 (contact light Not Guide 2010).

  [0099] The reflective portion of the third surface 2040 can include an air gap, and the window 2060 can include optically transparent contact with the contact dome 2080 and the “body” of the light guide 2010, which It can include using a smooth, planar coupling surface. Light having a shallow angle of incidence on the third surface 2040 (ie, with an angle A greater than normal to the surface) can be reflected off the third surface 2040.

  [00100] Light passing through an open window 2060 (eg, light 2000) is reflected by a reflector (eg, reflector 2070) back toward the surface (eg, third surface 2040) Can do. Such reflection can result in reflected light 2000 having a large angle of incidence with respect to third surface 2040 and / or second surface 2030, which is from light guide 2010 (eg, via second surface 2030). Can result in the passage of light. Such an angle is shown schematically in FIG. 20 via a smaller TIR angle A relative to the surface normal.

  [00101] Various dimensions (eg, 2062, 2070, 2074, 2014, etc.) can be selected according to application requirements. For example, as the radius 2062 of the circular window 2060 decreases, the light passing through the window 2060 can behave more and more as if it reaches the reflector 2070 from the “point source”, which is the second surface Providing a specific geometry (eg, parabolic) utilization for reflector 2070 that results in light exiting light guide 2010 through second surface 1030 at an angle substantially perpendicular to 2030 it can.

  [00102] FIG. 21 illustrates an embodiment. Light 2100 can be guided by a light guide 2110. The light guide 2110 can include a surface 2130 and a surface 2140. Surface 2140 may be at least partially reflective to reflect incident light that is shallower (relative to the surface) or that reaches incident angle at a larger angle A relative to TIR (relative to the vertical surface). can do. In some cases, surface 2140 is surrounded by an air gap.

  [00103] The surface 2140 can include a window 2160, which can be in optical communication with a reflector 2170, which can be attached to a contact dome. Allowing the passage of light from light guide 2110 to reflector 2170, actuation of the contact dome could open window 2160, which could be reflected and passed back to light guide 2110. The reflector 2170 can be characterized by a dimension 2172. In an embodiment, the dimension 2172 is the size of a pixel (10%, 5%, 2%, or even 1%) of a display device configured to display light guided by the light guide 2110. ). In some embodiments, the light source outputs light guided by the light guide 2110. In certain cases, each pixel associated with a display device may be associated with a window 2160 and / or a reflector 2170.

  [00104] Surface 2130 may include a "lens" or other shape associated with the transmission of light by surface 2130. In some cases, the shape of this lens can be chosen to modify the angle of light transmission from the surface 2130. For example, gently divergent illumination can be modified to be parallel and / or perpendicular to the plane associated with the light guide 2100.

  [00105] FIGS. 22A and 22B illustrate an open / close window. In FIG. 22A, the contact dome 2080 contacts the light guide 2010, allowing light 2000 to pass through the open window 2060 to the contact dome 2080. Light 2000 is then reflected by reflector 2070 back into light guide 2010 at an incident angle that results in the transmission of reflected light by light guide 2010 and exits light guide 2010 through surface 2030. Can. In FIG. 22B, the contact dome 2080 is not in contact with the light guide 2010, and thus the window 2061 is “closed” for the passage of light of at least a small angle. As a result, light 2000 that has passed through the (open) window can be internally reflected within light guide 2010 and cannot exit light guide 2010 (eg, surface 2030 shown in FIG. 22A). [00106] FIG. 22B also illustrates the coupling surface 2222 associated with the contact dome 2080. In certain embodiments, the coupling surface may be complementary (ie, matching) on at least a portion of the surface of the light guide (eg, surface 2040). The coupling surface between the two bodies can create an optically transparent window that allows substantially the passage of light at any incident angle. Opening the corresponding surface 2040 of the air gap by opening a gap (eg, by acting on the contact dome 2080) between the coupling surface 2222 and the corresponding surface 2040, which is reflective (eg, the region Can cause a TIR in the incident light above) and result in that region.

  [00107] The above disclosure is not intended to be limiting. Those skilled in the art will immediately observe the numerous modifications and retain the teachings of the present invention, as well as apparatus modifications. Accordingly, the above disclosure should be construed as limited only by the metes and bounds of the appended claims.

Claims (61)

A first surface 2020 configured to receive light 2000 from a light source;
A second surface 2030;
A third surface 2040;
A light guide 2010 including:
A matching surface 2222 configured to mate with at least a portion of the third surface 2040 in a manner that forms an optically transparent window 2060 when the surfaces meet.
A reflector 2070 in optical communication with the matching surface 2222 that is incident on the reflector 2070 from the window 2060 at an angle that causes transmission of at least a portion of the light 2000 reflected through the second surface 2030. A reflector 2070 comprising a shape configured to reflect at least a portion of the light 2000;
A contact dome 2080 comprising:
An actuator attached to both the contact dome 2080 and the light guide 2010;
And the actuator is configured to move the matching surface 2222 away from the third surface 2040 resulting in a matching surface 2222 in contact with the third surface 2040. ,system.   Both the first surface 2020 and the third surface 2040 reflect light arriving from within the light guide 2010 at an angle of incidence that is less than the angle associated with total reflection of light into the light guide 2010 by the surface. The system of claim 1, characterized in that:   The system of claim 1 or 2, wherein the open window transmits light that reaches the window 2060 from an angle at which the matching surface 2222 contacts the third surface 2040.   4. The system according to claim 1, wherein the first dimension is 100 times larger than the second dimension 2014. 5.   The system of any one of the preceding claims, wherein a first dimension associated with the window 2060 is ten times greater than a second dimension associated with the window 2060.   The system of any one of the preceding claims, wherein a first dimension associated with the reflector 2070 is ten times greater than a second dimension associated with the reflector 2070.   7. A system according to claim 5 or 6, wherein the first dimension is 100 times larger than the second dimension.   The system according to claim 1, wherein the window 2060 is curved.   The system of any one of claims 1 to 8, wherein at least a portion of the curvature of the reflector 2070 is parabolic.   The system according to claim 1, wherein at least a part of the curvature of the reflector 2070 is elliptical.   The system according to claim 1, wherein at least part of the curvature of the reflector 2070 is a plane.   12. A system according to any preceding claim, wherein the actuator includes one or more annular rings.   The system according to claim 1, wherein the actuator includes a piezoelectric actuator.   The system according to claim 1, wherein the contact dome 2080 is disposed on a TIR switch film 8.   15. A system according to any preceding claim, wherein the TIR switch film 8 and the contact dome 2080 are made from the same material.   The system according to claim 1, wherein the contact dome 2080 has a higher refractive index than the light guide 2010.   The system according to any one of the preceding claims, wherein the difference between the refractive indices of the light guide 2010 and the contact dome 2080 is less than 10%.   The system according to claim 1, wherein the contact dome has the same refractive index as the light guide 2010.   19. The light transmitted through the second surface 2030 is transmitted at an angle within 20 degrees from the perpendicular to the second surface 2030. The system described in.   The system of claim 19, wherein the angle is within 5 degrees of vertical.   21. The dimensions associated with both the contact dome 2080 and the matching surface 2222 are selected to be approximately the same as the dimensions of the pixels associated with the display screen incorporating the light guide 2010. The system according to any one of the above. A light source;
A system according to any one of claims 1 to 21,
A display component containing
A display component, wherein the system is configured to control light emission from a light source.   A display device comprising the system according to any one of claims 1 to 21.   A method of operating a light valve comprising using the system according to any one of claims 1 to 21. A light source;
A light guide,
A plurality of optical elements that allow selective extraction of light from the light guide;
Have
The light emitted from the light source passes through the light guide by total reflection,
The light passing through the light guide contacts one of the optical elements in the correct position, the light is extracted from the light guide through the optical element, and the light is transmitted to the viewer through a display device. Sent to
When light traveling through the light guide contacts one of the off-site optical elements, the light continues to travel through the light guide by total internal reflection;
A display device characterized by that. The optical element is disposed in a correct position where the light guide and the optical element are in physical contact;
The optical element is disposed at a position dislocated by maintaining a low refractive index near the surface of the light guide;
26. A display device according to claim 25, whereby the surface of the light guide maintains total reflection. The optical element is disposed in a correct position where the light guide and the optical element are in physical contact;
26. A display device according to claim 25, characterized in that at least one contact point of the light guide and the optical element creates a discontinuity of material that negates internal reflection of the light guide.   28. A display device according to claim 27, wherein the optical element is moved between a position displaced by electrostatic force and a correct position.   27. A display device according to claim 26, wherein the physical contact between the light guide and the optical element occurs on the opposite side of the light guide from the output side.   28. A display device according to claim 27, wherein the physical contact between the light guide and the optical element occurs on the opposite side of the light guide from the output side.   26. The display device of claim 25, wherein the selective extraction of light occurs at the interface of the light guide and control electronics panel.   27. A display device according to claim 26, wherein the selective extraction of light occurs at the interface of the light guide and control electronics panel.   28. A display device according to claim 27, wherein the selective extraction of light occurs at the interface of the light guide and control electronics panel.   26. A display device according to claim 25, wherein the light source produces red, green and blue light.   27. A display device according to claim 26, wherein the light source produces red, green and blue light.   28. The display device of claim 27, wherein the light source produces red, green, and blue light.   26. The display device of claim 25, wherein the light source generates red, green, blue, yellow, and cyano light.   27. The display device of claim 26, wherein the light source produces red, green, blue, yellow, and cyano light.   28. The display device of claim 27, wherein the light source produces red, green, blue, yellow, and cyano light.   26. A display device according to claim 25, wherein the light source produces white light.   27. The display device of claim 26, wherein the light source generates white light.   28. A display device according to claim 27, wherein the light source generates white light. A mask plate made of a light absorbing material is disposed between the output of the display device and the light guide,
The mask plate contains a plurality of apertures that allow light to pass through the mask plate;
26. A display device according to claim 25, wherein the mask plate thereby increases the contrast ratio of the output of the display device. A mask plate made of a light absorbing material is disposed between the output of the display device and the light guide,
The mask plate contains a plurality of apertures that allow light to pass through the mask plate;
27. A display device according to claim 26, wherein the mask plate increases the contrast ratio of the output of the display device. A mask plate made of a light absorbing material is disposed between the output of the display device and the light guide,
The mask plate contains a plurality of apertures that allow light to pass through the mask plate;
28. A display device according to claim 27, wherein the mask plate thereby increases the contrast ratio of the output of the display device. At least one diffusion layer is disposed between the output of the display device and the light guide;
26. A display device according to claim 25, wherein a diffusion layer extends the output of the display device to improve the visibility of the output from an angle off normal to the output. At least one diffusion layer is disposed between the output of the display device and the light guide;
27. A display device according to claim 26, wherein the diffusion layer extends the output of the display device to improve the visibility of the output from an angle off normal to the output. At least one diffusion layer is disposed between the output of the display device and the light guide;
28. A display device according to claim 27, wherein a diffusion layer extends the output of the display device to improve the visibility of the output from an angle off normal to the output. A light source;
A light guide,
A plurality of optical elements that allow selective extraction of light from the light guide;
Have
Light emitted from the light source passes through the light guide by total reflection;
Each of the optical elements comprises a reflective region;
The display device, wherein the reflection region directs light from the light guide to a viewer on an output side of the display device. When light passing through the light guide enters into contact with one of the optical elements in the correct position, light is extracted from the light guide through the optical element and the light is transmitted through the display device. To the viewer,
When light passing through the light guide contacts one of the optical elements in an off position, the light continues to travel through the light guide by total reflection;
Each optical element is placed in the correct position by physical contact of the optical element with the light guide, and the contact point of the optical element with the light guide creates a material discontinuity that negates the total reflection of the light guide 50. The display device of claim 49, wherein:   51. A display device according to claim 50, wherein the optical element moves between a position displaced by electrostatic force and a correct position.   52. The display device of claim 51, wherein the light source generates red, green, and blue light.   50. The display device of claim 49, wherein the light source generates red, green, and blue light.   50. The display device of claim 49, wherein the light source produces red, green, blue, yellow, and cyano light.   51. The display device of claim 50, wherein the light source generates red, green, blue, yellow, and cyano light.   50. A display device according to claim 49, wherein the light source produces white light.   51. The display device of claim 50, wherein the light source generates white light. A mask plate made of a light absorbing material is disposed between the output of the display device and the light guide,
The mask plate contains a plurality of apertures that allow light to pass through the mask plate;
50. A display device according to claim 49, wherein the mask plate thereby increases the contrast ratio of the output of the display device. A mask plate made of a light absorbing material is disposed between the output of the display device and the light guide,
The mask plate contains a plurality of apertures that allow light to pass through the mask plate;
51. A display device according to claim 50, wherein the mask plate thereby increases the contrast ratio of the output of the display device. At least one diffusion layer is disposed between the output of the display device and the light guide;
50. A display device according to claim 49, wherein the diffusion layer extends the output of the display device to improve the visibility of the output from an angle off normal to the output. At least one diffusion layer is disposed between the output of the display device and the light guide;
51. A display device according to claim 50, wherein the diffusion layer extends the output of the display device to improve the visibility of the output from an angle off normal to the output.

Images