Projection system

Abstract

The invention provides a projection system. The projection system comprises a display system, a first medium and a second medium, the display system is configured to emit light to predetermine a display image at a predetermined imaging position. The display system is disposed in a first medium having a first refractive index N1. The predetermined imaging position is located in a second medium, and the second medium has a second refractive index N2. The second medium is provided with a first side edge and a second side edge which are opposite to each other, the first side edge is located between the second side edge and the display system, a distance FR is formed between the first side edge and the second side edge, a first distance L1 is formed between the preset imaging position and the display system, and a second distance L2 is formed between the display system and the second medium; light has brightness BS before entering a second medium, light has attenuation rate beta in the second medium, and distance FR satisfies: # imgabs0 #

Description

Technical Field

[0001] The present invention relates to a projection system, in particular to a projection system capable of forming images in a liquid medium or a solid medium. Background Art

[0002] Existing liquid imaging systems can display images by placing a display device in a liquid medium. However, the display device placed in the liquid medium may affect the objects in the liquid medium. Therefore, how to improve the design of the liquid imaging system is still an important issue in the art. Summary of the invention

[0003] An object of the present invention is to provide a projection system, wherein the projection system can display images in a liquid medium or a solid medium.

[0004] In some embodiments, the present invention provides a projection system, including a display system, a first medium, and a second medium. The display system is configured to emit a light to display an image at a predetermined imaging position. The display system is disposed in a first medium, and the first medium has a first refractive index N1. The predetermined imaging position is located in a second medium, and the second medium has a second refractive index N2, wherein the second refractive index N2 is different from the first refractive index N1. The second medium has a first side and a second side relative to the first side, the first side is located between the second side and the display system, a distance FR is provided between the first side and the second side, a first distance L1 is provided between the predetermined imaging position and the display system, a second distance L2 is provided between the display system and the second medium, the light emitted by the display system has a brightness BS before entering the second medium, the light has an attenuation rate β in the second medium, and the distance FR satisfies:

[0005] BRIEF DESCRIPTION OF THE DRAWINGS

[0006] Figure 1 FIG. 1 is a schematic diagram of a projection system according to a first embodiment of the present invention.

[0007] Figure 2 FIG. 4 is a schematic diagram of a projection system according to a second embodiment of the present invention.

[0008] Figure 3 FIG. 4 is a schematic diagram of a projection system according to a third embodiment of the present invention.

[0009] Figure 4 FIG. 4 is a schematic structural diagram of a light modulation element according to a third embodiment of the present invention.

[0010] Figure 5 It is a structural schematic diagram of a light modulation element according to a variation of the third embodiment of the present invention.

[0011] Figure 6 FIG. 4 is a schematic diagram of a projection system according to a fourth embodiment of the present invention.

[0012] Figure 7 is a schematic diagram of a projection system according to a fifth embodiment of the present invention.

[0013] Figure 8 FIG. 4 is a schematic diagram of a projection system according to a sixth embodiment of the present invention.

[0014] Explanation of the reference numerals: AR-anti-reflection layer; BR-mask; BS, BS'-brightness; DS1, DS2, FR-distance; DD-display device; DS-display system; FP-focusing point; GR-grid; H1-minimum distance; IF-interactive interface; IM, IM'-image; IMP-predetermined imaging position; IMP'-actual imaging position; L1-first distance; La-length; LL-lower structure; LM-light modulation element; LN-lens; LS-light source; M1-first medium; M2-second medium; N1-first refractive index; N2-second refractive index; P1, P2-plate structure; PN-plane; PS-projection system; RF-reflecting surface; SS1-first side; SS2-second side; ST-slit; T1, LG-light; TL-upper structure; TN-trough; UR-user; X, Y, Z, D1, D2, D3-direction; θ1-angle. DETAILED DESCRIPTION

[0015] The present invention can be understood by referring to the following detailed description in conjunction with the accompanying drawings. It should be noted that in order to make it easier for readers to understand and for the simplicity of the drawings, the multiple drawings in the present invention only depict a portion of the device, and specific elements in the drawings are not drawn according to the actual scale. In addition, the number and size of each element in the figure are only for illustration and are not intended to limit the scope of the present invention.

[0016] Certain words are used throughout the specification and the appended claims to refer to specific components. It should be understood by those skilled in the art that electronic equipment manufacturers may refer to the same components by different names. This document does not intend to distinguish between components that have the same function but different names.

[0017] In the present specification and claims, the words “including” and “comprising” are open-ended words, and thus should be interpreted as meaning “including but not limited to…”.

[0018] It should be understood that when an element or a film layer is referred to as being "disposed on" or "connected to" another element or film layer, it may be directly on or directly connected to this other element or film layer, or there may be an intervening element or film layer between the two (indirect case). Conversely, when an element is referred to as being "directly on" or "directly connected to" another element or film layer, there may be no intervening element or film layer between the two. When an element or a film layer is referred to as being "electrically connected" to another element or film layer, it may be interpreted as a direct electrical connection or an indirect electrical connection. The electrical connection or coupling described in the present invention may refer to a direct connection or an indirect connection. In the case of a direct connection, the endpoints of the components on the two circuits are directly connected or connected to each other by a conductor segment, and in the case of an indirect connection, there is a switch, a diode, a capacitor, an inductor, a resistor, other suitable components, or a combination of the above components between the endpoints of the components on the two circuits, but is not limited thereto.

[0019] Although the terms "first", "second", "third" ... can be used to describe a variety of components, the components are not limited to these terms. These terms are only used to distinguish a single component from other components in the specification. The same terms may not be used in the claims, but may be replaced by first, second, third ... according to the order of the components in the claims. Therefore, in the specification of the present invention, the first component may be the second component in the claims.

[0020] In the present invention, the thickness, length and width may be measured by an optical microscope, and the thickness or width may be measured by a cross-sectional image in an electron microscope, but the present invention is not limited thereto.

[0021] In addition, any two values ​​or directions used for comparison may have a certain error. The terms "approximately", "equal to", "equal to" or "same", "substantially" or "substantially" are generally interpreted as being within a range of plus or minus 20% of the given value, or within a range of plus or minus 10%, plus or minus 5%, plus or minus 3%, plus or minus 2%, plus or minus 1% or plus or minus 0.5% of the given value.

[0022] In addition, the phrases “a given range is from a first value to a second value” and “a given range falls within the range from a first value to a second value” mean that the given range includes the first value, the second value and other values ​​therebetween.

[0023] If the first direction is perpendicular to the second direction, the angle between the first direction and the second direction may be between 80 degrees and 100 degrees; if the first direction is parallel to the second direction, the angle between the first direction and the second direction may be between 0 degrees and 10 degrees.

[0024] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meanings as commonly understood by those of ordinary skill in the art to which the present invention belongs. It is understood that these terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning consistent with the background or context of the relevant technology and the present invention, and should not be interpreted in an idealized or overly formal manner unless specifically defined in the embodiments of the present invention.

[0025] It should be noted that the following embodiments may be implemented by replacing, reorganizing, or mixing the technical features in several different embodiments without departing from the spirit of the present invention to complete other embodiments.

[0026] The projection system of the present invention may include an electronic device, wherein the electronic device may include a display device, a sensing device, an antenna device, a splicing device, a wearable device (for example, including augmented reality or virtual reality), other suitable electronic devices or a combination of the above devices, but not limited thereto. The electronic device may be a bendable, flexible or stretchable electronic device. The display device may include a non-self-luminous display device or a self-luminous display device. Non-self-luminous display devices include, for example, liquid crystal display devices, but not limited thereto. Self-luminous display devices include, for example, light-emitting diode display devices, but not limited thereto. The display device may be applied to, for example, a notebook computer, a public display, a splicing display, a car display, a touch display, a television, a monitor, a smart phone, a tablet computer, a light source module, a lighting device or, for example, an electronic device applied to the above products, but not limited thereto. The sensing device may include a biosensor, a touch sensor, a fingerprint sensor, other suitable sensors or a combination of the above types of sensors. The antenna device may be a liquid crystal type antenna device or a non-liquid crystal type antenna device, for example, including a liquid crystal antenna device, but not limited thereto. The splicing device may include, for example, a display splicing device or an antenna splicing device, but not limited thereto. The appearance of the electronic device may be rectangular, circular, polygonal, a shape with curved edges or other suitable shapes. The electronic device may include an electronic unit, wherein the electronic unit may include passive components and active components, such as capacitors, resistors, inductors, diodes, transistors, sensors, etc. The diode may include a light emitting diode or a photodiode. The light emitting diode may, for example, include an organic light emitting diode (OLED) or an inorganic light emitting diode (in-organic light emitting diode), and the inorganic light emitting diode may, for example, include a sub-millimeter light emitting diode (mini LED), a micro LED or a quantum dot light emitting diode (quantum dot LED), but is not limited thereto. It should be noted that the electronic device in the projection system of the present invention may be various combinations of the above devices, but is not limited thereto. The electronic device may have peripheral systems such as a drive system, a control system, a light source system, etc. to support a display device, an antenna device, a wearable device (such as including augmented reality or virtual reality), a vehicle-mounted device (such as including a car windshield), or a splicing device.

[0027] Please refer to Figure 1 , Figure 1 FIG. 1 is a schematic diagram of a projection system according to a first embodiment of the present invention. According to the present invention, the projection system PS may include a display system DS, a first medium M1 and a second medium M2. To simplify the drawings, Figure 1The display system DS is simply represented by a box, and the detailed structure of the display system DS is not shown. The display system DS is set in the first medium M1, or the display system DS can be placed in the first medium M1. In addition, the display system DS can be located outside the second medium M2, or not set in the second medium M2, but it is not limited to this. For example, the projection system PS can be formed by placing the second medium M2 and the display system DS in the first medium M1, but it is not limited to this.

[0028] The display system DS may include any system or device capable of displaying a floating image, such as a floating image display system, a light field display system, a holographic display system, or other suitable devices, but is not limited thereto. The display system DS may display an image at any suitable position in the projection system PS, depending on the location and structural design of the display system DS. The structure of the display system DS will be described in detail below. According to the present invention, the display system DS is configured to emit light (e.g., light T1) to pre-display an image IM at a pre-determined imaging position IMP. The "pre-determined imaging position IMP" refers to the position of the image IM that can be displayed in the environment of the first medium M1 after the display system DS emits the above light. The above-mentioned "environment of the first medium M1" refers to the environment when the environment only includes the first medium M1, that is, the display system DS, the path of the light, and the imaging position are all in the first medium M1 without passing through the second medium M2 or being located in the second medium M2. Specifically, the "predetermined imaging position IMP" can be defined as the position of the image (i.e., image IM) displayed by the display system DS when the projection system PS only includes the first medium M1 (i.e., does not include the second medium M2). That is, in the environment of the first medium M1, after the display system DS is placed, the display system DS can display the image IM, and the position of the image IM is the predetermined imaging position IMP mentioned above. The image IM can be, for example, parallel to the plane formed by the direction Y and the direction Z (i.e., plane YZ), but is not limited to this. In some embodiments, the image IM can be inclined to the plane YZ. It should be noted that although Figure 1The image IM shown is a planar image, but the present invention is not limited thereto. In some embodiments, the image IM may be a stereoscopic image. In the projection system PS, the predetermined imaging position IMP may be obtained, for example, in the following manner. First, the display system DS may be placed in an environment of the first medium M1, and the relative position of the display system DS and the image displayed thereon may be observed. Here, the "relative position of the display system DS and the image displayed thereon" may be, for example, the distance between the display system DS and the position of the image displayed thereon (i.e., the predetermined imaging position IMP). Specifically, there may be a first distance L1 between the predetermined imaging position IMP and the display system DS, wherein the value of the first distance L1 may be determined according to the design of the display system DS, and may not change with the change of the position of the display system DS in the first medium M1. Thus, after confirming the first distance L1, the position of the predetermined imaging position IMP may be obtained according to the position of the display system DS in the projection system PS and the value of the first distance L1. In this embodiment, the first distance L1 may be defined as the minimum distance between the predetermined imaging position IMP and the display system DS, but is not limited thereto.

[0029] According to the present invention, the first medium M1 and the second medium M2 include any suitable medium through which light can pass, so that the light T1 emitted by the display system DS can be imaged through the first medium M1 and the second medium M2. Specifically, the first medium M1 and the second medium M2 may include transparent media or high-transmittance media, respectively. The first medium M1 and the second medium M2 are different media. In this case, the first medium M1 has a first refractive index N1, and the second medium M2 has a second refractive index N2, wherein the first refractive index N1 is different from the second refractive index N2. In this embodiment, the first medium M1 may be a gas, and the second medium M2 may be a solid or a liquid. For example, the first medium M1 may be air, and the second medium M2 may be water, but is not limited thereto. In another embodiment, the first medium M1 may be air, and the second medium M2 may be ice. It should be noted that in an embodiment in which the second medium M2 includes a liquid, the projection system PS may, for example, include a second medium unit, wherein the second medium unit may include a slot TN and a second medium M2 disposed in the slot TN, such as Figure 1 In other words, the projection system PS may further include a slot TN to provide a space for accommodating the second medium M2. In another embodiment, when the second medium M2 includes a solid, the projection system PS may not include the slot TN. The first medium M1 and the second medium M2 may include any suitable transparent medium or high light transmittance medium, respectively, and are not limited to the above-mentioned mediums.

[0030] According to the present invention, the display system DS can be set at any suitable position in the first medium M1, so that the above-mentioned predetermined imaging position IMP is located in the second medium M2. Specifically, after the display system DS is set in the first medium M1 of the projection system PS, the image IM that is predetermined to be displayed by the display system DS is located in the second medium M2. In other words, the display system DS and the image IM that is predetermined to be displayed by it are located in different media. Specifically, the first distance L1 between the above-mentioned predetermined imaging position IMP and the display system DS can be confirmed first, and the setting position of the display system DS in the first medium M1 can be determined based on the first distance L1, so that the predetermined imaging position IMP can be located in the second medium M2. In detail, in the cross-sectional view of the projection system PS (for example Figure 1 ), the second medium M2 may have a first side SS1 and a second side SS2 relative to the first side SS1, wherein the first side SS1 is located between the second side SS2 and the display system DS. A distance DS1 may be provided between the first side SS1 and the display system DS, and a distance DS2 may be provided between the second side SS2 and the display system DS, wherein the display system DS may be disposed at any suitable position in the first medium M1, such that the distance DS1 is less than or equal to the first distance L1, and the distance DS2 is greater than or equal to the first distance L1. In this way, the predetermined imaging position IMP may be located in the second medium M2. When the first distance L1 is less than the distance DS1 or greater than the distance DS2, the predetermined imaging position IMP will fall outside the second medium M2. The distance DS1 and the distance DS2 may be defined as the minimum distances between the first side SS1 and the second side SS2 and the display system DS, respectively, but are not limited thereto. It should be noted that when the projection system PS includes a slot body TN for accommodating the second medium M2, the first side SS1 and the second side SS2 may be defined as two mutually opposite sides of the slot body TN.

[0031] According to the present invention, since the first medium M1 and the second medium M2 can be different media, the display system DS will deviate from the predetermined imaging position IMP when imaging in the second medium M2, or in other words, the image displayed by the display system DS in the second medium M2 is not actually Figure 1 Specifically, Figure 1 As shown in FIG. 1 , when the light T1 emitted by the display system DS enters the second medium M2, the display system DS forms an image IM' at an actual imaging position IMP', wherein the image IM' deviates from the predetermined imaging position IMP. In other words, the actual imaging position IMP' is different from the predetermined imaging position IMP. In some embodiments, in the direction X, the predetermined imaging position IMP may be between the image IM' and the display system DS, such as Figure 1As shown. In other embodiments, in the direction X, the image IM' may be between the predetermined imaging position IMP and the display system DS. In other words, the light T1 emitted by the display system DS will actually be imaged at the actual imaging position IMP' after entering the second medium M2. According to the present invention, in the cross-sectional view of the projection system PS, there is a distance FR between the first side SS1 and the second side SS2, there is a first distance L1 (as described above) between the predetermined imaging position IMP and the display system DS, there is a second distance L2 between the display system DS and the second medium M2, the first medium M1 has a first refractive index N1, and the second medium M2 has a second refractive index N2, wherein the distance FR may satisfy the following formula (1):

[0032]

[0033] The distance FR can also be regarded as the width of the second medium M2 in the direction X. In some embodiments, when the projection system PS includes a slot TN, the distance FR can be regarded as the width of the slot TN. The unit of each distance in formula (1) is centimeter (cm). The second distance L2 can be defined as the minimum distance between the display system DS and the second medium M2. For example, the second distance L2 can be the distance between the display system DS and the first side SS1 of the second medium M2. In this case, the second distance L2 is the distance DS1 mentioned above.

[0034] According to the present invention, by making the distance FR fall within the range of the above formula (1), the actual imaging position IMP' (or the image IM') can be located in the second medium M2, thereby achieving the effect of displaying the image in the second medium M2 through the display system DS located outside the second medium M2. Specifically, by making the distance FR fall within the range of the above formula (1), even if the image IM' (or the actual imaging position IMP') deviates from the predetermined imaging position IMP, it can still be located in the second medium M2. In detail, the display system DS can be placed at any suitable position in the first medium M1 so that the predetermined setting position IMP can be located in the second medium M2. Next, the position (i.e., predetermined imaging position IMP) of the image (i.e., image IM) displayed by the display system DS in the environment of the first medium M1 (i.e., the environment only includes the first medium M1) and the distance between the display system DS (i.e., first distance L1), the distance between the display system DS and the second medium M2 (i.e., second distance L2), the first refractive index N1 of the first medium M1, and the second refractive index N2 of the second medium M2 can be confirmed, and the width of the second medium M2 (i.e., distance FR) can be designed by the above formula (1), so that the display system DS can display the image in the second medium M2. Under this design, the display system DS can be not set in the second medium M2 but can still be imaged in the second medium M2, so that the influence of the display system DS on the objects in the second medium M2 can be reduced, thereby increasing the application scenarios of the projection system PS. For example, in one embodiment, the projection system PS may include a display system DS and an aquarium (a second medium M2, a second refractive index N2 of approximately 1.33) placed in air (a first medium M1, a first refractive index N1 of approximately 1). After confirming the first distance L1 between the position (i.e., the predetermined display position IMP) of the image (i.e., image IM) displayed by the display system DS in a general air environment and the display system DS and the distance (i.e., the second distance L2) between the display system DS and the aquarium, the width of the aquarium may be designed according to formula (1) so that the display system DS can be imaged in the aquarium. Alternatively, the distance (i.e., the second distance L2) between the display system DS and the aquarium may be designed according to the width of the aquarium. Since the display system DS is not disposed in the aquarium, it will not affect the movement of organisms in the aquarium or occupy the space of the aquarium. It should be noted that the above application scenarios are merely exemplary and the present invention is not limited thereto. In addition, although Figure 1 The image IM′ shown is an image parallel to the plane YZ, but the present invention is not limited thereto.

[0035] In the present embodiment, in the direction X, the user UR can view the image IM' displayed by the display system DS on the side of the second medium M2 opposite to the display system DS, that is, the second medium M2 can be located between the user UR and the display system DS, but is not limited thereto. In some embodiments, the user UR can view the image IM' in the second medium M2 in any direction. In other words, the light T1 emitted by the display system DS can first pass through the second medium M2 and then be observed by the user UR. The brightness of the light may decrease after passing through the second medium M2. Specifically, the light T1 has a brightness BS before entering the second medium M2, and the light T1 has a brightness BS' after passing through the second medium M2, wherein the brightness BS' is less than the brightness BS. The degree of brightness reduction of the light after passing through the second medium M2 can be determined according to the attenuation rate β of the light in the second medium M2. When the attenuation rate β is larger, the brightness of the light after passing through the second medium M2 (i.e., the brightness BS') is smaller. According to the present embodiment, the attenuation rate β of the light in the second medium M2 can be measured, for example, in the following manner. First, a laser can be emitted by a laser emitting instrument and passed through a slot body including a second medium M2 and having a width of 10 cm. Then, the brightness IL of the laser before passing through the second medium M2 and the brightness IS of the laser after passing through the second medium M2 can be measured by any suitable brightness measurement equipment, and the attenuation rate β can be obtained by the following formula (2):

[0036]

[0037] According to this embodiment, the above distance FR, the brightness BS of the light T1 emitted by the display system DS before passing through the second medium M2, and the attenuation rate β of the light in the second medium M2 may also satisfy the following formula (3):

[0038]

[0039] In formula (3), the unit of distance FR is centimeter, and the unit of brightness BS is nit.

[0040] By making the distance FR fall within the range of the above formula (3), the possibility that the brightness of the light after passing through the second medium M2 is too low and affects the experience of the user UR can be reduced. Specifically, by making the distance FR, the brightness BS and the attenuation rate β satisfy the above formula (3), the brightness of the light after passing through the second medium M2 can be at least 300 nit, thereby reducing the situation where the brightness of the image IM' observed by the user UR is too low. For example, in one embodiment, the brightness BS of the light T1 emitted by the display system DS is 600 nit, and the attenuation rate β of the light in the second medium M2 is 0.5. In this case, the distance FR (or the width of the second medium M2) can be designed to be less than or equal to 100 cm, but is not limited thereto.

[0041] Therefore, after combining equation (1) and equation (3), the range of the distance FR between the first side SS1 and the second side SS2 of the second medium M2 (or the width of the second medium M2) can be obtained as shown in the following equation (4):

[0042]

[0043] According to the present invention, by making the distance FR (or the width of the second medium M2) fall within the range of formula (4), the image IM' can be displayed in the second medium M2 by the display system DS disposed in the first medium M1, wherein the brightness of the image IM' observed by the user can be maintained above a required brightness (for example, 300 nit, but not limited thereto), thereby increasing the application scenarios of the projection system PS or improving the experience of the user UR.

[0044] More embodiments of the present invention will be described below. To simplify the description, the same film layers or components in the following embodiments will use the same labels, and their features will not be repeated, while the differences between the embodiments will be described in detail in the present invention. It should be noted that the features described in each embodiment can be applied to each other and are not limited to the structure of the embodiment.

[0045] Please refer to Figure 2 , Figure 2 FIG. 1 is a schematic diagram of a projection system according to a second embodiment of the present invention. Figure 2The predetermined imaging position IMP is not shown. According to the present embodiment, the projection system PS may further include an anti-reflection layer AR, wherein the anti-reflection layer AR may be disposed on the surface of the second medium M2. In some embodiments, the anti-reflection layer AR may be disposed on the surface of the first side SS1, that is, the anti-reflection layer AR may be disposed between the display system DS and the second medium M2. In this case, when the second medium M2 includes a solid, the anti-reflection layer AR may be directly disposed on the surface of the first side SS1 of the second medium M2 and contact the second medium; and when the second medium M2 includes a liquid and is contained in the tank body TN, the anti-reflection layer AR may be disposed on the surface of the first side SS1 facing the display system DS (or the outer surface of the tank body TN opposite to the second medium M2) or on the surface facing the second medium M2 (for example, the inner surface of the tank body TN), but is not limited thereto. In some embodiments, the anti-reflection layer AR may be disposed on the surface of the second side SS2. In this case, when the second medium M2 includes a solid, the anti-reflection layer AR can be directly disposed on the surface of the second side SS2 of the second medium M2 and contact the second medium; and when the second medium M2 includes a liquid and is contained in the tank TN, the anti-reflection layer AR can be disposed on the surface of the second side SS2 facing the first side SS1 (or the inner surface of the tank TN) or on the surface of the second side SS2 opposite to the second medium M2 (for example, the outer surface of the tank TN), but not limited thereto. In some embodiments, the anti-reflection layer AR can be disposed on the inner surface and / or outer surface of the first side SS1 and the second side SS2 at the same time, and its arrangement method can refer to the above. The anti-reflection layer AR may include any suitable anti-reflection material. Specifically, the anti-reflection layer AR can be formed by coating an anti-reflection material on the surface of the second medium M2 or the tank TN, but not limited thereto. By setting an anti-reflection layer AR on the surface of the first side SS1 and / or the second side SS2 of the second medium M2, the possibility of light being reflected at the interface between the first medium M1 and the second medium M2 when entering the second medium M2 or emitting from the second medium M2 can be reduced, thereby improving the experience of the user UR. The feature of the projection system PS in this embodiment including the anti-reflection layer AR can be applied to various embodiments of the present invention. In some embodiments, the possibility of light reflection can be reduced by setting the display system DS in the second medium M2. In this case, the display system DS can be set to one side of the first side SS1 to reduce the impact on the objects in the second medium M2.

[0046] Please refer to Figure 3 and Figure 4 , Figure 3 is a schematic diagram of a projection system according to a third embodiment of the present invention, Figure 4Schematic diagram of the structure of the light modulation element of the third embodiment of the present invention. According to this embodiment, the display system DS in the projection system PS may include a light modulation element LM and a display device DD, or the display system DS may be composed of a light modulation element LM and a display device DD. The light modulation element LM and the display device DD are arranged in the first medium M1. The light modulation element LM and the display device DD may be located outside the second medium M2, but not limited to this. The display device DD may include a display panel, wherein the display panel may be a self-luminous display panel or a non-self-luminous display panel, but not limited to this. The non-self-luminous display panel includes, for example, a liquid crystal display panel, and the self-luminous display panel includes, for example, a light-emitting diode display panel, but not limited to this. Figure 3 The display device DD is only exemplarily represented by a single film layer, and the detailed structure of the display device DD is not shown. The display device DD may include, for example, a substrate, a circuit layer and a light-emitting layer (or a light modulation layer) disposed on the substrate, or other suitable elements or film layers. It should be noted that the display device DD may also include other suitable devices, and is not limited to the above-mentioned devices.

[0047] The light modulator LM is used to focus the light emitted by the display device DD on the side of the light modulator LM opposite to the display device DD, thereby displaying an image. That is, the display device DD and the image displayed by the display device DD can be located on both sides of the light modulator LM. In other words, the display device DD can display a suspended image through the light modulator LM, and the display system DS can be a suspended image display system. The light modulator LM can include any suitable multi-reflection optical structure (such as a retroreflector, but not limited thereto). Figure 4 FIG. 4 shows a schematic diagram of the structure of the light modulation element LM of this embodiment at two different viewing angles. Figure 4 As shown, the light modulation element LM may be a flat plate-shaped element, wherein the flat plate-shaped element includes a plurality of grids GR arranged in an array. Figure 4 As shown in the structure (I), the light modulation element LM may have a grid-like structure in the top view direction and include a plurality of grids GR, wherein the plurality of grids GR may be arranged in a matrix along the direction D1 and the direction D2. Figure 4As shown in the structure (II), in the side view direction, the light modulation element LM has a thickness, which is the thickness of the flat-plate element, wherein the thickness of the light modulation element LM can be defined in a direction D3. Direction D3 can be perpendicular to direction D1 and direction D2. In this case, the plane of the light modulation element LM can be parallel to the plane formed by direction D1 and direction D2 (hereinafter referred to as plane D12), and plane D12 can be called the plane of the light modulation element LM. In addition, direction D3 can be the thickness direction of the light modulation element LM. In this embodiment, a grid GR of the light modulation element LM can be formed by surrounding four planes PN, wherein the planes PN can be reflective surfaces, such as mirror surfaces, but not limited thereto. That is, when light strikes the plane PN, it can be reflected by the plane. For example, a flat-plate element having a plurality of grids GR can be first formed with any suitable material (such as glass, but not limited thereto), and then a reflective material can be coated on the plane PN surrounding the grid GR to form a reflective surface, but not limited thereto. Through the structure of the above-mentioned light modulator LM, when the light emitted by the light source LS passes through the light modulator LM, the part of the light parallel to the direction D3 can penetrate the light modulator LM, and the part of the light perpendicular to the direction D3 can be reflected by the plane PN of the light modulator LM (for example, secondary reflection). In this case, the light emitted from the light source LS will be focused on the focal point FP on the side of the light modulator LM opposite to the light source LS, and the light source LS and the focal point FP can be symmetrical to each other with the light modulator LM as the symmetry plane. In detail, in the coordinate system composed of the direction D1, the direction D2 and the direction D3, when the coordinates (D1, D2, D3) of the light source LS are (A1, B1, C1), the coordinates (D1, D2, D3) of the focal point FP where the light emitted by the light source LS is focused after passing through the light modulator LM can be (A1, B1, -C1), that is, the coordinates of the light source LS and the focal point FP in the directions D1 and D2 remain unchanged, and the coordinates in the direction D3 are opposite to each other. Thus, the light emitted by the light source LS can be imaged on the side of the light modulator LM opposite to the light source LS in the thickness direction (direction D3) of the light modulator LM. Figure 4 The light source LS and the focus point FP shown in the structure (I) are actually located on both sides of the light modulation element LM, as shown in FIG. Figure 4 The structure (II) is shown. In addition, Figure 4 The structure of the light modulation element LM shown is only exemplary, and the present embodiment is not limited thereto.

[0048] Please refer to Figure 3According to this embodiment, the light modulator LM and the display device DD can be set at any suitable position in the first medium M1, so that the display device DD can be predetermined to display the image IM at the predetermined imaging position IMP. The features of the image IM and the predetermined imaging position IMP can be referred to above, so they will not be repeated here. Through the above-mentioned structure of the light modulator LM, the display device DD and the predetermined imaging position IMP can be located on both sides of the light modulator LM in the thickness direction of the light modulator LM (direction D3). In this embodiment, in the normal direction of the display device DD (i.e., direction Z), the light modulator LM can be set on the display device DD, and the second medium M2 can be located on the left or right side of the light modulator LM ( Figure 3 In addition, in the normal direction of the display device DD, the light modulator LM and the display device DD may have an angle θ1, wherein the angle θ1 may range from 20 degrees to 70 degrees (i.e., 20°≤θ1≤70°). In some embodiments, the angle θ1 may range from 30 degrees to 60 degrees (i.e., 30°≤θ1≤60°). In some embodiments, the angle θ1 may range from 40 degrees to 50 degrees (i.e., 40°≤θ1≤50°). For example, Figure 3 As shown, the display device DD can be arranged in parallel with the plane XY, the light modulator LM can be arranged on the display device DD and the angle θ1 between the light modulator LM and the display device DD is 45 degrees, and the second medium M2 can be arranged on the left side of the light modulator LM, but it is not limited to this. Through the above arrangement, the image IM to be displayed by the display device DD can be located in the second medium M2. It should be noted that Figure 3 The configuration of the display system DS shown is merely exemplary, and the present embodiment is not limited thereto.

[0049] According to this embodiment, the light modulation element LM and the display device DD may have a minimum distance H1 in the normal direction of the display device DD. Figure 3As shown, the minimum distance H1 may be the distance between the lower end of the light modulator LM and the upper surface of the display device DD in the normal direction of the display device DD, but is not limited thereto. The display device DD may have a center brightness BC. Specifically, the center brightness BC may be the brightness of light measured at the center of the display device DD. The center brightness BC may be the brightness of the light emitted from the center of the display device DD before entering the light modulator LM. In some embodiments, the center brightness BC may be the same as the brightness BS (the brightness before the light enters the second medium M2) described above. The display device DD may have a light source (not shown) to predeterminedly display an image IM, wherein the light source may have a distance maintenance rate α, and the image IM may have a brightness Bi. The distance maintenance rate α may be obtained in the following manner. First, the brightness intensity I0 of the light source of the display device DD can be measured at a distance of 0 cm from the display device DD by a brightness measuring device (such as a display measuring system (DMS), but not limited thereto), and then the brightness intensity I1 of the light source of the display device DD can be measured at a distance of 100 cm from the display device DD, and the distance maintenance rate α of the light source of the display device DD can be I1 / I0. The light modulator LM can have a length La, wherein the length La can be defined as the length of the light modulator LM in the direction D2. In addition, the light modulator LM can have a light efficiency η. The light efficiency η can be measured in an appropriate manner by any suitable brightness measuring device. For example, in the measurement of the light efficiency η, the intensity of the incident light incident from the incident surface of the light modulator LM and the intensity of the outgoing light emitted from the light emitting surface can be measured by a brightness measuring device, and the light efficiency η of the light modulator LM can be the ratio of the outgoing light intensity to the incident light intensity, but not limited thereto.

[0050] According to this embodiment, the minimum distance H1 may satisfy the following equation (5):

[0051]

[0052] In formula (5), the units of the minimum distance H1 and the length La are centimeters, and the units of the center brightness BC and the brightness Bi are nits.

[0053] According to this embodiment, the minimum distance H1 between the light modulator LM and the display device DD, the center brightness BS of the display device DD, the distance maintenance rate α of the light source of the display device DD, the length La of the light modulator LM, and the light efficiency η of the light modulator LM can be adjusted according to the above formula (5) so that the brightness Bi of the image IM is at a required brightness (for example, 300 nit, but not limited to this), thereby improving the user UR experience. For example, after confirming the center brightness BS, the distance maintenance rate α, the length La, and the light efficiency η, the brightness Bi of the image can be adjusted by adjusting the minimum distance H1 between the light modulator LM and the display device DD. For example, in one embodiment, the center brightness BC of the display device DD is 1700 nit, the distance maintenance rate α of the light source of the display device DD is 0.9, the light efficiency η of the light modulator LM is 0.25, and the length La of the light modulator LM is 200 cm. In this case, the minimum distance H1 can be designed to be 70 cm, so that the brightness Bi of the image IM is about 316 nit, which is greater than the above required brightness.

[0054] In addition, in this embodiment, the distance FR between the first side SS1 and the second side SS2 of the second medium M2 can satisfy the above formula (1), so that the actual imaging of the display system DS can still be located in the second medium M2. In detail, as described above, after the light emitted by the display system DS enters the second medium M2, it will form an image IM' (not shown) at the actual imaging position IMP' (not shown), wherein the actual imaging position IMP' may be different from the predetermined imaging position IMP. In order to simplify the drawings, Figure 3 The image IM' and the actual imaging position IMP' where the image IM' is located are not shown. It should be noted that the brightness Bi of the above-mentioned image IM is also the brightness of the image IM', that is, the brightness of the image actually observed by the user UR. Specifically, in this embodiment, the first distance L1 in formula (1) can be defined as the minimum distance between the predetermined imaging position IMP and the light modulator LM in the direction X. For example, the first distance L1 can be the distance between the predetermined imaging position IMP and the lower end of the light modulator LM in the direction X, but is not limited to this. The second distance L2 in formula (1) can be defined as the minimum distance between the second medium M2 and the light modulator LM in the direction X. For example, the second distance L2 can be the distance between the first side SS1 of the second medium M2 and the lower end of the light modulator LM in the direction X, but is not limited to this. In this way, the range of the distance FR can be designed by formula (1).

[0055] Please refer to Figure 5 , Figure 5Schematic diagram of the structure of a light modulator of a variation of the third embodiment of the present invention. According to this variation, the light modulator LM may include a double-layer structure, which includes a lower structure LL and an upper structure TL disposed on the lower structure LL. The lower structure LL may include a plurality of plate-like structures P1 extending along a direction X, and the plurality of plate-like structures P1 are arranged along a direction Y; the upper structure TL may include a plurality of plate-like structures P2 extending along a direction Y, and the plurality of plate-like structures P2 are arranged along a direction X. In other words, the extension direction of the plate-like structure P1 is perpendicular to the extension direction of the plate-like structure P2, and the arrangement direction of the plate-like structure P1 is perpendicular to the arrangement direction of the plate-like structure P2. The plate-like structure P1 and the plate-like structure P2 may include a reflective surface RF, such as a mirror surface, but not limited thereto. The reflective surfaces RF of the plurality of plate-like structures P1 may face the same direction, such as the direction X. The reflective surfaces RF of the plurality of plate-like structures P2 may face the same direction, such as the direction -Y. In some embodiments, the plate-like structure P1 and the plate-like structure P2 may include a plurality of reflective surfaces RF, such as a double-sided mirror structure. For example, a mirror surface may be formed on the surface of a plate-like glass to form the plate-like structure P1 and the plate-like structure P2, but the present invention is not limited thereto. In other words, the light modulation element LM of this variation may include a double-layer vertical mirror structure. Figure 5 A plate-like structure P1 and a plate-like structure P2 in the light modulation element LM are shown. Figure 5 As shown in the structure (II), the light LG emitted by the light source LS can be reflected (i.e., secondary reflection) at the reflection surface RF of the plate-like structure P1 of the lower structure LL and the reflection surface RF of the plate-like structure P2 of the upper structure TL when passing through the light modulator LM, thereby forming an image on the side of the light modulator LM opposite to the light source LS. The light modulator LM of this variation can be applied to Figure 3 The display system DS is shown.

[0056] Please refer to Figure 6 , Figure 6 FIG. 4 is a schematic diagram of a projection system according to a fourth embodiment of the present invention. The display system DS in the projection system PS of this embodiment may include a light field display system, such as a barrier type light field display system. Figure 6 As shown, the display system DS may include a display device DD and a mask BR disposed on the light emitting surface of the display device DD. The mask BR includes a plurality of slits ST, so that it has a structure in which light and dark stripes are alternately arranged. The mask BR is located between the display device DD and the second medium M2. The display device DD may refer to Figure 3The relevant description is omitted. The display system DS can be set at any suitable position in the first medium M1 so that it can pre-display the image IM in the second medium M2. The distance FR between the first side SS1 and the second side SS2 of the second medium M2 can satisfy the above formula (4), so that the actual imaging position of the display system in the second medium M2 (i.e., the above-mentioned actual imaging position IMP', not shown in FIG. 4 ) is Figure 6 ) can still be located in the second medium M2. Specifically, in this embodiment, the first distance L1 in formula (4) can be defined as the minimum distance between the predetermined imaging position IMP and the mask BR in the direction X, and the second distance L2 can be defined as the minimum distance between the first side SS1 of the second medium M2 and the mask BR in the direction X, but is not limited thereto. The structure of the display system DS of this embodiment can be applied to the projection system PS of the above-mentioned embodiments.

[0057] Please refer to Figure 7 , Figure 7 FIG. 5 is a schematic diagram of a projection system according to a fifth embodiment of the present invention. The display system DS in the projection system PS of this embodiment may include a light field display system, such as a lens array type light field display system. Figure 7 As shown, the display system DS may include a display device DD and a plurality of lenses LN disposed on the light emitting surface of the display device DD, wherein the plurality of lenses LN may be arranged in a matrix. The lenses LN may be located between the display device DD and the second medium M2. The display system DS may be disposed at any suitable position in the first medium M1 so that it can pre-display an image IM in the second medium M2. The distance FR between the first side SS1 and the second side SS2 of the second medium M2 may satisfy the above formula (4), so that the actual imaging position of the display system in the second medium M2 (i.e., the above-mentioned actual imaging position IMP', not shown) Figure 7 ) can still be located in the second medium M2. Specifically, in this embodiment, the first distance L1 in formula (4) can be defined as the minimum distance between the predetermined imaging position IMP and the lens LN in the direction X, and the second distance L2 can be defined as the minimum distance between the first side SS1 of the second medium M2 and the lens LN in the direction X, but is not limited thereto. The structure of the display system DS of this embodiment can be applied to the projection system PS of the above-mentioned embodiments.

[0058] Please refer to Figure 8 , Figure 8 FIG. 6 is a schematic diagram of a projection system according to a sixth embodiment of the present invention. According to this embodiment, the projection system PS may further include an interactive interface IF, and the user UR may interact with the image IM' displayed by the display system DS in the second medium M2 through the interactive interface IF. The interactive interface IF may be disposed at any suitable position in the projection system PS, and may not be used in any manner. Figure 8The interactive interface IF is shown as a limitation. In some embodiments, the interactive interface IF may include a keyboard, a mouse, a game controller or other suitable input devices, and the user UR can operate the image IM' through the interactive interface IF. In some embodiments, the interactive interface IF may be the surface of the slot TN that accommodates the second medium M2, that is, the user UR can interact with the image IM' by touching the surface of the slot TN. For example, the interactive interface IF may be the surface of the slot TN adjacent to the user UR, that is, the surface of the slot TN corresponding to the second side SS2. In some embodiments, the above-mentioned interactive interface IF may mean that the user UR can operate the image IM' through gesture control. For example, an image sensing device (not shown) may be selectively included to detect the user's actions, such as gestures or other suitable actions. By detecting the actions through the image sensing device, the user can interact with the image IM' through the actions. The image sensing device may, for example, include an infrared image sensor, a camera or other suitable image capture device. It should be noted that the above-mentioned example of the interactive interface IF is only exemplary, and the present embodiment is not limited thereto. The interactive interface IF of this embodiment can be applied to the projection system PS of the above-mentioned embodiment.

[0059] In summary, the present invention provides a projection system, which includes a first medium, a display system disposed in the first medium, and a second medium. The display system can be disposed at any suitable position in the first medium, so that the image to be displayed can be located in the second medium. In addition, by designing the width of the second medium, the image actually displayed by the projection system can still be located in the second medium even if it deviates from the predetermined imaging position. Furthermore, the width design of the second medium can make the brightness of the image displayed by the projection system greater than the required brightness, thereby improving the user experience.

[0060] The above description is only an embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A projection system, characterized in that: include: A display system configured to emit a light beam to display an image at a predetermined imaging position; a first medium, wherein the display system is disposed in the first medium, and the first medium has a first refractive index N1; a second medium, wherein the predetermined imaging position is located in the second medium, and the second medium has a second refractive index N2, and the second refractive index N2 is different from the first refractive index N1; The second medium has a first side and a second side opposite to the first side, the first side is located between the second side and the display system, a distance FR is between the first side and the second side, a first distance L1 is between the predetermined imaging position and the display system, a second distance L2 is between the display system and the second medium, the light has a brightness BS before entering the second medium, the light has an attenuation rate β in the second medium, and the distance FR satisfies: The unit of the distance FR is centimeter.

2. The projection system according to claim 1, characterized in that: After the light enters the second medium, the image is displayed at an actual imaging position, the actual imaging position is located in the second medium, and the actual imaging position is different from the predetermined imaging position.

3. The projection system according to claim 1, characterized in that: The device also includes an anti-reflection layer, which is arranged between the display system and the second medium.

4. The projection system according to claim 1, characterized in that: The invention also includes an anti-reflection layer, wherein the anti-reflection layer is arranged on a surface of the second side edge facing the first side edge.

5. The projection system according to claim 1, characterized in that: The display system includes a light modulation element and a display device. In a normal direction of the display device, the light modulation element is arranged on the display device and has an angle with the display device, wherein the angle ranges from 20 degrees to 70 degrees.

6. The projection system according to claim 5, characterized in that: The light modulator and the display device have a minimum distance H1 in the normal direction of the display device, the display device has a center brightness BC, the display device has a light source to display the image, the image has a brightness Bi, the light source has a distance maintenance rate α, the light modulator has a light efficiency η, and the light modulator has a length La, wherein the minimum distance H1 satisfies: The unit of the minimum distance H1 is centimeters.

7. The projection system according to claim 1, characterized in that: The first medium is air.

8. The projection system according to claim 1, characterized in that: The second medium is liquid or solid.

9. The projection system according to claim 1, characterized in that: It also includes a tank body, in which the second medium is arranged.

10. The projection system according to claim 1, characterized in that: The display system includes a holographic image display system or a light field display system.

Images